diff options
Diffstat (limited to 'arch/powerpc/mm/nohash')
-rw-r--r-- | arch/powerpc/mm/nohash/40x.c | 156 | ||||
-rw-r--r-- | arch/powerpc/mm/nohash/44x.c | 242 | ||||
-rw-r--r-- | arch/powerpc/mm/nohash/8xx.c | 210 | ||||
-rw-r--r-- | arch/powerpc/mm/nohash/Makefile | 19 | ||||
-rw-r--r-- | arch/powerpc/mm/nohash/book3e_pgtable.c | 132 | ||||
-rw-r--r-- | arch/powerpc/mm/nohash/e500.c | 375 | ||||
-rw-r--r-- | arch/powerpc/mm/nohash/e500_hugetlbpage.c | 190 | ||||
-rw-r--r-- | arch/powerpc/mm/nohash/kaslr_booke.c | 396 | ||||
-rw-r--r-- | arch/powerpc/mm/nohash/kup.c | 33 | ||||
-rw-r--r-- | arch/powerpc/mm/nohash/mmu_context.c | 425 | ||||
-rw-r--r-- | arch/powerpc/mm/nohash/tlb.c | 745 | ||||
-rw-r--r-- | arch/powerpc/mm/nohash/tlb_low.S | 472 | ||||
-rw-r--r-- | arch/powerpc/mm/nohash/tlb_low_64e.S | 1169 |
13 files changed, 4564 insertions, 0 deletions
diff --git a/arch/powerpc/mm/nohash/40x.c b/arch/powerpc/mm/nohash/40x.c new file mode 100644 index 000000000..3684d6e57 --- /dev/null +++ b/arch/powerpc/mm/nohash/40x.c @@ -0,0 +1,156 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * This file contains the routines for initializing the MMU + * on the 4xx series of chips. + * -- paulus + * + * Derived from arch/ppc/mm/init.c: + * Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org) + * + * Modifications by Paul Mackerras (PowerMac) (paulus@cs.anu.edu.au) + * and Cort Dougan (PReP) (cort@cs.nmt.edu) + * Copyright (C) 1996 Paul Mackerras + * + * Derived from "arch/i386/mm/init.c" + * Copyright (C) 1991, 1992, 1993, 1994 Linus Torvalds + */ + +#include <linux/signal.h> +#include <linux/sched.h> +#include <linux/kernel.h> +#include <linux/errno.h> +#include <linux/string.h> +#include <linux/types.h> +#include <linux/ptrace.h> +#include <linux/mman.h> +#include <linux/mm.h> +#include <linux/swap.h> +#include <linux/stddef.h> +#include <linux/vmalloc.h> +#include <linux/init.h> +#include <linux/delay.h> +#include <linux/highmem.h> +#include <linux/memblock.h> + +#include <asm/io.h> +#include <asm/mmu_context.h> +#include <asm/mmu.h> +#include <linux/uaccess.h> +#include <asm/smp.h> +#include <asm/bootx.h> +#include <asm/machdep.h> +#include <asm/setup.h> + +#include <mm/mmu_decl.h> + +/* + * MMU_init_hw does the chip-specific initialization of the MMU hardware. + */ +void __init MMU_init_hw(void) +{ + /* + * The Zone Protection Register (ZPR) defines how protection will + * be applied to every page which is a member of a given zone. At + * present, we utilize only two of the 4xx's zones. + * The zone index bits (of ZSEL) in the PTE are used for software + * indicators, except the LSB. For user access, zone 1 is used, + * for kernel access, zone 0 is used. We set all but zone 1 + * to zero, allowing only kernel access as indicated in the PTE. + * For zone 1, we set a 01 binary (a value of 10 will not work) + * to allow user access as indicated in the PTE. This also allows + * kernel access as indicated in the PTE. + */ + + mtspr(SPRN_ZPR, 0x10000000); + + flush_instruction_cache(); + + /* + * Set up the real-mode cache parameters for the exception vector + * handlers (which are run in real-mode). + */ + + mtspr(SPRN_DCWR, 0x00000000); /* All caching is write-back */ + + /* + * Cache instruction and data space where the exception + * vectors and the kernel live in real-mode. + */ + + mtspr(SPRN_DCCR, 0xFFFF0000); /* 2GByte of data space at 0x0. */ + mtspr(SPRN_ICCR, 0xFFFF0000); /* 2GByte of instr. space at 0x0. */ +} + +#define LARGE_PAGE_SIZE_16M (1<<24) +#define LARGE_PAGE_SIZE_4M (1<<22) + +unsigned long __init mmu_mapin_ram(unsigned long base, unsigned long top) +{ + unsigned long v, s, mapped; + phys_addr_t p; + + v = KERNELBASE; + p = 0; + s = total_lowmem; + + if (IS_ENABLED(CONFIG_KFENCE)) + return 0; + + if (debug_pagealloc_enabled()) + return 0; + + if (strict_kernel_rwx_enabled()) + return 0; + + while (s >= LARGE_PAGE_SIZE_16M) { + pmd_t *pmdp; + unsigned long val = p | _PMD_SIZE_16M | _PAGE_EXEC | _PAGE_RW; + + pmdp = pmd_off_k(v); + *pmdp++ = __pmd(val); + *pmdp++ = __pmd(val); + *pmdp++ = __pmd(val); + *pmdp++ = __pmd(val); + + v += LARGE_PAGE_SIZE_16M; + p += LARGE_PAGE_SIZE_16M; + s -= LARGE_PAGE_SIZE_16M; + } + + while (s >= LARGE_PAGE_SIZE_4M) { + pmd_t *pmdp; + unsigned long val = p | _PMD_SIZE_4M | _PAGE_EXEC | _PAGE_RW; + + pmdp = pmd_off_k(v); + *pmdp = __pmd(val); + + v += LARGE_PAGE_SIZE_4M; + p += LARGE_PAGE_SIZE_4M; + s -= LARGE_PAGE_SIZE_4M; + } + + mapped = total_lowmem - s; + + /* If the size of RAM is not an exact power of two, we may not + * have covered RAM in its entirety with 16 and 4 MiB + * pages. Consequently, restrict the top end of RAM currently + * allocable so that calls to the MEMBLOCK to allocate PTEs for "tail" + * coverage with normal-sized pages (or other reasons) do not + * attempt to allocate outside the allowed range. + */ + memblock_set_current_limit(mapped); + + return mapped; +} + +void setup_initial_memory_limit(phys_addr_t first_memblock_base, + phys_addr_t first_memblock_size) +{ + /* We don't currently support the first MEMBLOCK not mapping 0 + * physical on those processors + */ + BUG_ON(first_memblock_base != 0); + + /* 40x can only access 16MB at the moment (see head_40x.S) */ + memblock_set_current_limit(min_t(u64, first_memblock_size, 0x00800000)); +} diff --git a/arch/powerpc/mm/nohash/44x.c b/arch/powerpc/mm/nohash/44x.c new file mode 100644 index 000000000..1beae802b --- /dev/null +++ b/arch/powerpc/mm/nohash/44x.c @@ -0,0 +1,242 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Modifications by Matt Porter (mporter@mvista.com) to support + * PPC44x Book E processors. + * + * This file contains the routines for initializing the MMU + * on the 4xx series of chips. + * -- paulus + * + * Derived from arch/ppc/mm/init.c: + * Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org) + * + * Modifications by Paul Mackerras (PowerMac) (paulus@cs.anu.edu.au) + * and Cort Dougan (PReP) (cort@cs.nmt.edu) + * Copyright (C) 1996 Paul Mackerras + * + * Derived from "arch/i386/mm/init.c" + * Copyright (C) 1991, 1992, 1993, 1994 Linus Torvalds + */ + +#include <linux/init.h> +#include <linux/memblock.h> + +#include <asm/mmu.h> +#include <asm/page.h> +#include <asm/cacheflush.h> +#include <asm/code-patching.h> +#include <asm/smp.h> + +#include <mm/mmu_decl.h> + +/* Used by the 44x TLB replacement exception handler. + * Just needed it declared someplace. + */ +unsigned int tlb_44x_index; /* = 0 */ +unsigned int tlb_44x_hwater = PPC44x_TLB_SIZE - 1 - PPC44x_EARLY_TLBS; +int icache_44x_need_flush; + +unsigned long tlb_47x_boltmap[1024/8]; + +static void __init ppc44x_update_tlb_hwater(void) +{ + /* The TLB miss handlers hard codes the watermark in a cmpli + * instruction to improve performances rather than loading it + * from the global variable. Thus, we patch the instructions + * in the 2 TLB miss handlers when updating the value + */ + modify_instruction_site(&patch__tlb_44x_hwater_D, 0xffff, tlb_44x_hwater); + modify_instruction_site(&patch__tlb_44x_hwater_I, 0xffff, tlb_44x_hwater); +} + +/* + * "Pins" a 256MB TLB entry in AS0 for kernel lowmem for 44x type MMU + */ +static void __init ppc44x_pin_tlb(unsigned int virt, unsigned int phys) +{ + unsigned int entry = tlb_44x_hwater--; + + ppc44x_update_tlb_hwater(); + + mtspr(SPRN_MMUCR, 0); + + __asm__ __volatile__( + "tlbwe %2,%3,%4\n" + "tlbwe %1,%3,%5\n" + "tlbwe %0,%3,%6\n" + : + : "r" (PPC44x_TLB_SW | PPC44x_TLB_SR | PPC44x_TLB_SX | PPC44x_TLB_G), + "r" (phys), + "r" (virt | PPC44x_TLB_VALID | PPC44x_TLB_256M), + "r" (entry), + "i" (PPC44x_TLB_PAGEID), + "i" (PPC44x_TLB_XLAT), + "i" (PPC44x_TLB_ATTRIB)); +} + +static int __init ppc47x_find_free_bolted(void) +{ + unsigned int mmube0 = mfspr(SPRN_MMUBE0); + unsigned int mmube1 = mfspr(SPRN_MMUBE1); + + if (!(mmube0 & MMUBE0_VBE0)) + return 0; + if (!(mmube0 & MMUBE0_VBE1)) + return 1; + if (!(mmube0 & MMUBE0_VBE2)) + return 2; + if (!(mmube1 & MMUBE1_VBE3)) + return 3; + if (!(mmube1 & MMUBE1_VBE4)) + return 4; + if (!(mmube1 & MMUBE1_VBE5)) + return 5; + return -1; +} + +static void __init ppc47x_update_boltmap(void) +{ + unsigned int mmube0 = mfspr(SPRN_MMUBE0); + unsigned int mmube1 = mfspr(SPRN_MMUBE1); + + if (mmube0 & MMUBE0_VBE0) + __set_bit((mmube0 >> MMUBE0_IBE0_SHIFT) & 0xff, + tlb_47x_boltmap); + if (mmube0 & MMUBE0_VBE1) + __set_bit((mmube0 >> MMUBE0_IBE1_SHIFT) & 0xff, + tlb_47x_boltmap); + if (mmube0 & MMUBE0_VBE2) + __set_bit((mmube0 >> MMUBE0_IBE2_SHIFT) & 0xff, + tlb_47x_boltmap); + if (mmube1 & MMUBE1_VBE3) + __set_bit((mmube1 >> MMUBE1_IBE3_SHIFT) & 0xff, + tlb_47x_boltmap); + if (mmube1 & MMUBE1_VBE4) + __set_bit((mmube1 >> MMUBE1_IBE4_SHIFT) & 0xff, + tlb_47x_boltmap); + if (mmube1 & MMUBE1_VBE5) + __set_bit((mmube1 >> MMUBE1_IBE5_SHIFT) & 0xff, + tlb_47x_boltmap); +} + +/* + * "Pins" a 256MB TLB entry in AS0 for kernel lowmem for 47x type MMU + */ +static void __init ppc47x_pin_tlb(unsigned int virt, unsigned int phys) +{ + unsigned int rA; + int bolted; + + /* Base rA is HW way select, way 0, bolted bit set */ + rA = 0x88000000; + + /* Look for a bolted entry slot */ + bolted = ppc47x_find_free_bolted(); + BUG_ON(bolted < 0); + + /* Insert bolted slot number */ + rA |= bolted << 24; + + pr_debug("256M TLB entry for 0x%08x->0x%08x in bolt slot %d\n", + virt, phys, bolted); + + mtspr(SPRN_MMUCR, 0); + + __asm__ __volatile__( + "tlbwe %2,%3,0\n" + "tlbwe %1,%3,1\n" + "tlbwe %0,%3,2\n" + : + : "r" (PPC47x_TLB2_SW | PPC47x_TLB2_SR | + PPC47x_TLB2_SX +#ifdef CONFIG_SMP + | PPC47x_TLB2_M +#endif + ), + "r" (phys), + "r" (virt | PPC47x_TLB0_VALID | PPC47x_TLB0_256M), + "r" (rA)); +} + +void __init MMU_init_hw(void) +{ + /* This is not useful on 47x but won't hurt either */ + ppc44x_update_tlb_hwater(); + + flush_instruction_cache(); +} + +unsigned long __init mmu_mapin_ram(unsigned long base, unsigned long top) +{ + unsigned long addr; + unsigned long memstart = memstart_addr & ~(PPC_PIN_SIZE - 1); + + /* Pin in enough TLBs to cover any lowmem not covered by the + * initial 256M mapping established in head_44x.S */ + for (addr = memstart + PPC_PIN_SIZE; addr < lowmem_end_addr; + addr += PPC_PIN_SIZE) { + if (mmu_has_feature(MMU_FTR_TYPE_47x)) + ppc47x_pin_tlb(addr + PAGE_OFFSET, addr); + else + ppc44x_pin_tlb(addr + PAGE_OFFSET, addr); + } + if (mmu_has_feature(MMU_FTR_TYPE_47x)) { + ppc47x_update_boltmap(); + +#ifdef DEBUG + { + int i; + + printk(KERN_DEBUG "bolted entries: "); + for (i = 0; i < 255; i++) { + if (test_bit(i, tlb_47x_boltmap)) + printk("%d ", i); + } + printk("\n"); + } +#endif /* DEBUG */ + } + return total_lowmem; +} + +void setup_initial_memory_limit(phys_addr_t first_memblock_base, + phys_addr_t first_memblock_size) +{ + u64 size; + +#ifndef CONFIG_NONSTATIC_KERNEL + /* We don't currently support the first MEMBLOCK not mapping 0 + * physical on those processors + */ + BUG_ON(first_memblock_base != 0); +#endif + + /* 44x has a 256M TLB entry pinned at boot */ + size = (min_t(u64, first_memblock_size, PPC_PIN_SIZE)); + memblock_set_current_limit(first_memblock_base + size); +} + +#ifdef CONFIG_SMP +void __init mmu_init_secondary(int cpu) +{ + unsigned long addr; + unsigned long memstart = memstart_addr & ~(PPC_PIN_SIZE - 1); + + /* Pin in enough TLBs to cover any lowmem not covered by the + * initial 256M mapping established in head_44x.S + * + * WARNING: This is called with only the first 256M of the + * linear mapping in the TLB and we can't take faults yet + * so beware of what this code uses. It runs off a temporary + * stack. current (r2) isn't initialized, smp_processor_id() + * will not work, current thread info isn't accessible, ... + */ + for (addr = memstart + PPC_PIN_SIZE; addr < lowmem_end_addr; + addr += PPC_PIN_SIZE) { + if (mmu_has_feature(MMU_FTR_TYPE_47x)) + ppc47x_pin_tlb(addr + PAGE_OFFSET, addr); + else + ppc44x_pin_tlb(addr + PAGE_OFFSET, addr); + } +} +#endif /* CONFIG_SMP */ diff --git a/arch/powerpc/mm/nohash/8xx.c b/arch/powerpc/mm/nohash/8xx.c new file mode 100644 index 000000000..dbbfe8974 --- /dev/null +++ b/arch/powerpc/mm/nohash/8xx.c @@ -0,0 +1,210 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * This file contains the routines for initializing the MMU + * on the 8xx series of chips. + * -- christophe + * + * Derived from arch/powerpc/mm/40x_mmu.c: + */ + +#include <linux/memblock.h> +#include <linux/hugetlb.h> + +#include <mm/mmu_decl.h> + +#define IMMR_SIZE (FIX_IMMR_SIZE << PAGE_SHIFT) + +static unsigned long block_mapped_ram; + +/* + * Return PA for this VA if it is in an area mapped with LTLBs or fixmap. + * Otherwise, returns 0 + */ +phys_addr_t v_block_mapped(unsigned long va) +{ + unsigned long p = PHYS_IMMR_BASE; + + if (va >= VIRT_IMMR_BASE && va < VIRT_IMMR_BASE + IMMR_SIZE) + return p + va - VIRT_IMMR_BASE; + if (va >= PAGE_OFFSET && va < PAGE_OFFSET + block_mapped_ram) + return __pa(va); + return 0; +} + +/* + * Return VA for a given PA mapped with LTLBs or fixmap + * Return 0 if not mapped + */ +unsigned long p_block_mapped(phys_addr_t pa) +{ + unsigned long p = PHYS_IMMR_BASE; + + if (pa >= p && pa < p + IMMR_SIZE) + return VIRT_IMMR_BASE + pa - p; + if (pa < block_mapped_ram) + return (unsigned long)__va(pa); + return 0; +} + +static pte_t __init *early_hugepd_alloc_kernel(hugepd_t *pmdp, unsigned long va) +{ + if (hpd_val(*pmdp) == 0) { + pte_t *ptep = memblock_alloc(sizeof(pte_basic_t), SZ_4K); + + if (!ptep) + return NULL; + + hugepd_populate_kernel((hugepd_t *)pmdp, ptep, PAGE_SHIFT_8M); + hugepd_populate_kernel((hugepd_t *)pmdp + 1, ptep, PAGE_SHIFT_8M); + } + return hugepte_offset(*(hugepd_t *)pmdp, va, PGDIR_SHIFT); +} + +static int __ref __early_map_kernel_hugepage(unsigned long va, phys_addr_t pa, + pgprot_t prot, int psize, bool new) +{ + pmd_t *pmdp = pmd_off_k(va); + pte_t *ptep; + + if (WARN_ON(psize != MMU_PAGE_512K && psize != MMU_PAGE_8M)) + return -EINVAL; + + if (new) { + if (WARN_ON(slab_is_available())) + return -EINVAL; + + if (psize == MMU_PAGE_512K) + ptep = early_pte_alloc_kernel(pmdp, va); + else + ptep = early_hugepd_alloc_kernel((hugepd_t *)pmdp, va); + } else { + if (psize == MMU_PAGE_512K) + ptep = pte_offset_kernel(pmdp, va); + else + ptep = hugepte_offset(*(hugepd_t *)pmdp, va, PGDIR_SHIFT); + } + + if (WARN_ON(!ptep)) + return -ENOMEM; + + /* The PTE should never be already present */ + if (new && WARN_ON(pte_present(*ptep) && pgprot_val(prot))) + return -EINVAL; + + set_huge_pte_at(&init_mm, va, ptep, pte_mkhuge(pfn_pte(pa >> PAGE_SHIFT, prot))); + + return 0; +} + +/* + * MMU_init_hw does the chip-specific initialization of the MMU hardware. + */ +void __init MMU_init_hw(void) +{ +} + +static bool immr_is_mapped __initdata; + +void __init mmu_mapin_immr(void) +{ + if (immr_is_mapped) + return; + + immr_is_mapped = true; + + __early_map_kernel_hugepage(VIRT_IMMR_BASE, PHYS_IMMR_BASE, + PAGE_KERNEL_NCG, MMU_PAGE_512K, true); +} + +static void mmu_mapin_ram_chunk(unsigned long offset, unsigned long top, + pgprot_t prot, bool new) +{ + unsigned long v = PAGE_OFFSET + offset; + unsigned long p = offset; + + WARN_ON(!IS_ALIGNED(offset, SZ_512K) || !IS_ALIGNED(top, SZ_512K)); + + for (; p < ALIGN(p, SZ_8M) && p < top; p += SZ_512K, v += SZ_512K) + __early_map_kernel_hugepage(v, p, prot, MMU_PAGE_512K, new); + for (; p < ALIGN_DOWN(top, SZ_8M) && p < top; p += SZ_8M, v += SZ_8M) + __early_map_kernel_hugepage(v, p, prot, MMU_PAGE_8M, new); + for (; p < ALIGN_DOWN(top, SZ_512K) && p < top; p += SZ_512K, v += SZ_512K) + __early_map_kernel_hugepage(v, p, prot, MMU_PAGE_512K, new); + + if (!new) + flush_tlb_kernel_range(PAGE_OFFSET + v, PAGE_OFFSET + top); +} + +unsigned long __init mmu_mapin_ram(unsigned long base, unsigned long top) +{ + unsigned long etext8 = ALIGN(__pa(_etext), SZ_8M); + unsigned long sinittext = __pa(_sinittext); + bool strict_boundary = strict_kernel_rwx_enabled() || debug_pagealloc_enabled_or_kfence(); + unsigned long boundary = strict_boundary ? sinittext : etext8; + unsigned long einittext8 = ALIGN(__pa(_einittext), SZ_8M); + + WARN_ON(top < einittext8); + + mmu_mapin_immr(); + + mmu_mapin_ram_chunk(0, boundary, PAGE_KERNEL_TEXT, true); + if (debug_pagealloc_enabled_or_kfence()) { + top = boundary; + } else { + mmu_mapin_ram_chunk(boundary, einittext8, PAGE_KERNEL_TEXT, true); + mmu_mapin_ram_chunk(einittext8, top, PAGE_KERNEL, true); + } + + if (top > SZ_32M) + memblock_set_current_limit(top); + + block_mapped_ram = top; + + return top; +} + +void mmu_mark_initmem_nx(void) +{ + unsigned long etext8 = ALIGN(__pa(_etext), SZ_8M); + unsigned long sinittext = __pa(_sinittext); + unsigned long boundary = strict_kernel_rwx_enabled() ? sinittext : etext8; + unsigned long einittext8 = ALIGN(__pa(_einittext), SZ_8M); + + if (!debug_pagealloc_enabled_or_kfence()) + mmu_mapin_ram_chunk(boundary, einittext8, PAGE_KERNEL, false); + + mmu_pin_tlb(block_mapped_ram, false); +} + +#ifdef CONFIG_STRICT_KERNEL_RWX +void mmu_mark_rodata_ro(void) +{ + unsigned long sinittext = __pa(_sinittext); + + mmu_mapin_ram_chunk(0, sinittext, PAGE_KERNEL_ROX, false); + if (IS_ENABLED(CONFIG_PIN_TLB_DATA)) + mmu_pin_tlb(block_mapped_ram, true); +} +#endif + +void __init setup_initial_memory_limit(phys_addr_t first_memblock_base, + phys_addr_t first_memblock_size) +{ + /* We don't currently support the first MEMBLOCK not mapping 0 + * physical on those processors + */ + BUG_ON(first_memblock_base != 0); + + /* 8xx can only access 32MB at the moment */ + memblock_set_current_limit(min_t(u64, first_memblock_size, SZ_32M)); +} + +int pud_clear_huge(pud_t *pud) +{ + return 0; +} + +int pmd_clear_huge(pmd_t *pmd) +{ + return 0; +} diff --git a/arch/powerpc/mm/nohash/Makefile b/arch/powerpc/mm/nohash/Makefile new file mode 100644 index 000000000..f3894e79d --- /dev/null +++ b/arch/powerpc/mm/nohash/Makefile @@ -0,0 +1,19 @@ +# SPDX-License-Identifier: GPL-2.0 + +ccflags-$(CONFIG_PPC64) := $(NO_MINIMAL_TOC) + +obj-y += mmu_context.o tlb.o tlb_low.o kup.o +obj-$(CONFIG_PPC_BOOK3E_64) += tlb_low_64e.o book3e_pgtable.o +obj-$(CONFIG_40x) += 40x.o +obj-$(CONFIG_44x) += 44x.o +obj-$(CONFIG_PPC_8xx) += 8xx.o +obj-$(CONFIG_PPC_E500) += e500.o +obj-$(CONFIG_RANDOMIZE_BASE) += kaslr_booke.o +ifdef CONFIG_HUGETLB_PAGE +obj-$(CONFIG_PPC_E500) += e500_hugetlbpage.o +endif + +# Disable kcov instrumentation on sensitive code +# This is necessary for booting with kcov enabled on book3e machines +KCOV_INSTRUMENT_tlb.o := n +KCOV_INSTRUMENT_e500.o := n diff --git a/arch/powerpc/mm/nohash/book3e_pgtable.c b/arch/powerpc/mm/nohash/book3e_pgtable.c new file mode 100644 index 000000000..b80fc4a91 --- /dev/null +++ b/arch/powerpc/mm/nohash/book3e_pgtable.c @@ -0,0 +1,132 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Copyright 2005, Paul Mackerras, IBM Corporation. + * Copyright 2009, Benjamin Herrenschmidt, IBM Corporation. + * Copyright 2015-2016, Aneesh Kumar K.V, IBM Corporation. + */ + +#include <linux/sched.h> +#include <linux/memblock.h> +#include <asm/pgalloc.h> +#include <asm/tlb.h> +#include <asm/dma.h> +#include <asm/code-patching.h> + +#include <mm/mmu_decl.h> + +#ifdef CONFIG_SPARSEMEM_VMEMMAP +/* + * On Book3E CPUs, the vmemmap is currently mapped in the top half of + * the vmalloc space using normal page tables, though the size of + * pages encoded in the PTEs can be different + */ +int __meminit vmemmap_create_mapping(unsigned long start, + unsigned long page_size, + unsigned long phys) +{ + /* Create a PTE encoding without page size */ + unsigned long i, flags = _PAGE_PRESENT | _PAGE_ACCESSED | + _PAGE_KERNEL_RW; + + /* PTEs only contain page size encodings up to 32M */ + BUG_ON(mmu_psize_defs[mmu_vmemmap_psize].enc > 0xf); + + /* Encode the size in the PTE */ + flags |= mmu_psize_defs[mmu_vmemmap_psize].enc << 8; + + /* For each PTE for that area, map things. Note that we don't + * increment phys because all PTEs are of the large size and + * thus must have the low bits clear + */ + for (i = 0; i < page_size; i += PAGE_SIZE) + BUG_ON(map_kernel_page(start + i, phys, __pgprot(flags))); + + return 0; +} + +#ifdef CONFIG_MEMORY_HOTPLUG +void vmemmap_remove_mapping(unsigned long start, + unsigned long page_size) +{ +} +#endif +#endif /* CONFIG_SPARSEMEM_VMEMMAP */ + +static void __init *early_alloc_pgtable(unsigned long size) +{ + void *ptr; + + ptr = memblock_alloc_try_nid(size, size, MEMBLOCK_LOW_LIMIT, + __pa(MAX_DMA_ADDRESS), NUMA_NO_NODE); + + if (!ptr) + panic("%s: Failed to allocate %lu bytes align=0x%lx max_addr=%lx\n", + __func__, size, size, __pa(MAX_DMA_ADDRESS)); + + return ptr; +} + +/* + * map_kernel_page currently only called by __ioremap + * map_kernel_page adds an entry to the ioremap page table + * and adds an entry to the HPT, possibly bolting it + */ +int __ref map_kernel_page(unsigned long ea, unsigned long pa, pgprot_t prot) +{ + pgd_t *pgdp; + p4d_t *p4dp; + pud_t *pudp; + pmd_t *pmdp; + pte_t *ptep; + + BUILD_BUG_ON(TASK_SIZE_USER64 > PGTABLE_RANGE); + if (slab_is_available()) { + pgdp = pgd_offset_k(ea); + p4dp = p4d_offset(pgdp, ea); + pudp = pud_alloc(&init_mm, p4dp, ea); + if (!pudp) + return -ENOMEM; + pmdp = pmd_alloc(&init_mm, pudp, ea); + if (!pmdp) + return -ENOMEM; + ptep = pte_alloc_kernel(pmdp, ea); + if (!ptep) + return -ENOMEM; + } else { + pgdp = pgd_offset_k(ea); + p4dp = p4d_offset(pgdp, ea); + if (p4d_none(*p4dp)) { + pudp = early_alloc_pgtable(PUD_TABLE_SIZE); + p4d_populate(&init_mm, p4dp, pudp); + } + pudp = pud_offset(p4dp, ea); + if (pud_none(*pudp)) { + pmdp = early_alloc_pgtable(PMD_TABLE_SIZE); + pud_populate(&init_mm, pudp, pmdp); + } + pmdp = pmd_offset(pudp, ea); + if (!pmd_present(*pmdp)) { + ptep = early_alloc_pgtable(PTE_TABLE_SIZE); + pmd_populate_kernel(&init_mm, pmdp, ptep); + } + ptep = pte_offset_kernel(pmdp, ea); + } + set_pte_at(&init_mm, ea, ptep, pfn_pte(pa >> PAGE_SHIFT, prot)); + + smp_wmb(); + return 0; +} + +void __patch_exception(int exc, unsigned long addr) +{ + unsigned int *ibase = &interrupt_base_book3e; + + /* + * Our exceptions vectors start with a NOP and -then- a branch + * to deal with single stepping from userspace which stops on + * the second instruction. Thus we need to patch the second + * instruction of the exception, not the first one. + */ + + patch_branch(ibase + (exc / 4) + 1, addr, 0); +} diff --git a/arch/powerpc/mm/nohash/e500.c b/arch/powerpc/mm/nohash/e500.c new file mode 100644 index 000000000..40a4e69ae --- /dev/null +++ b/arch/powerpc/mm/nohash/e500.c @@ -0,0 +1,375 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Modifications by Kumar Gala (galak@kernel.crashing.org) to support + * E500 Book E processors. + * + * Copyright 2004,2010 Freescale Semiconductor, Inc. + * + * This file contains the routines for initializing the MMU + * on the 4xx series of chips. + * -- paulus + * + * Derived from arch/ppc/mm/init.c: + * Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org) + * + * Modifications by Paul Mackerras (PowerMac) (paulus@cs.anu.edu.au) + * and Cort Dougan (PReP) (cort@cs.nmt.edu) + * Copyright (C) 1996 Paul Mackerras + * + * Derived from "arch/i386/mm/init.c" + * Copyright (C) 1991, 1992, 1993, 1994 Linus Torvalds + */ + +#include <linux/signal.h> +#include <linux/sched.h> +#include <linux/kernel.h> +#include <linux/errno.h> +#include <linux/string.h> +#include <linux/types.h> +#include <linux/ptrace.h> +#include <linux/mman.h> +#include <linux/mm.h> +#include <linux/swap.h> +#include <linux/stddef.h> +#include <linux/vmalloc.h> +#include <linux/init.h> +#include <linux/delay.h> +#include <linux/highmem.h> +#include <linux/memblock.h> +#include <linux/of_fdt.h> + +#include <asm/io.h> +#include <asm/mmu_context.h> +#include <asm/mmu.h> +#include <linux/uaccess.h> +#include <asm/smp.h> +#include <asm/machdep.h> +#include <asm/setup.h> +#include <asm/paca.h> + +#include <mm/mmu_decl.h> + +unsigned int tlbcam_index; + +struct tlbcam TLBCAM[NUM_TLBCAMS]; + +static struct { + unsigned long start; + unsigned long limit; + phys_addr_t phys; +} tlbcam_addrs[NUM_TLBCAMS]; + +#ifdef CONFIG_PPC_85xx +/* + * Return PA for this VA if it is mapped by a CAM, or 0 + */ +phys_addr_t v_block_mapped(unsigned long va) +{ + int b; + for (b = 0; b < tlbcam_index; ++b) + if (va >= tlbcam_addrs[b].start && va < tlbcam_addrs[b].limit) + return tlbcam_addrs[b].phys + (va - tlbcam_addrs[b].start); + return 0; +} + +/* + * Return VA for a given PA or 0 if not mapped + */ +unsigned long p_block_mapped(phys_addr_t pa) +{ + int b; + for (b = 0; b < tlbcam_index; ++b) + if (pa >= tlbcam_addrs[b].phys + && pa < (tlbcam_addrs[b].limit-tlbcam_addrs[b].start) + +tlbcam_addrs[b].phys) + return tlbcam_addrs[b].start+(pa-tlbcam_addrs[b].phys); + return 0; +} +#endif + +/* + * Set up a variable-size TLB entry (tlbcam). The parameters are not checked; + * in particular size must be a power of 4 between 4k and the max supported by + * an implementation; max may further be limited by what can be represented in + * an unsigned long (for example, 32-bit implementations cannot support a 4GB + * size). + */ +static void settlbcam(int index, unsigned long virt, phys_addr_t phys, + unsigned long size, unsigned long flags, unsigned int pid) +{ + unsigned int tsize; + + tsize = __ilog2(size) - 10; + +#if defined(CONFIG_SMP) || defined(CONFIG_PPC_E500MC) + if ((flags & _PAGE_NO_CACHE) == 0) + flags |= _PAGE_COHERENT; +#endif + + TLBCAM[index].MAS0 = MAS0_TLBSEL(1) | MAS0_ESEL(index) | MAS0_NV(index+1); + TLBCAM[index].MAS1 = MAS1_VALID | MAS1_IPROT | MAS1_TSIZE(tsize) | MAS1_TID(pid); + TLBCAM[index].MAS2 = virt & PAGE_MASK; + + TLBCAM[index].MAS2 |= (flags & _PAGE_WRITETHRU) ? MAS2_W : 0; + TLBCAM[index].MAS2 |= (flags & _PAGE_NO_CACHE) ? MAS2_I : 0; + TLBCAM[index].MAS2 |= (flags & _PAGE_COHERENT) ? MAS2_M : 0; + TLBCAM[index].MAS2 |= (flags & _PAGE_GUARDED) ? MAS2_G : 0; + TLBCAM[index].MAS2 |= (flags & _PAGE_ENDIAN) ? MAS2_E : 0; + + TLBCAM[index].MAS3 = (phys & MAS3_RPN) | MAS3_SR; + TLBCAM[index].MAS3 |= (flags & _PAGE_RW) ? MAS3_SW : 0; + if (mmu_has_feature(MMU_FTR_BIG_PHYS)) + TLBCAM[index].MAS7 = (u64)phys >> 32; + + /* Below is unlikely -- only for large user pages or similar */ + if (pte_user(__pte(flags))) { + TLBCAM[index].MAS3 |= MAS3_UR; + TLBCAM[index].MAS3 |= (flags & _PAGE_EXEC) ? MAS3_UX : 0; + TLBCAM[index].MAS3 |= (flags & _PAGE_RW) ? MAS3_UW : 0; + } else { + TLBCAM[index].MAS3 |= (flags & _PAGE_EXEC) ? MAS3_SX : 0; + } + + tlbcam_addrs[index].start = virt; + tlbcam_addrs[index].limit = virt + size - 1; + tlbcam_addrs[index].phys = phys; +} + +static unsigned long calc_cam_sz(unsigned long ram, unsigned long virt, + phys_addr_t phys) +{ + unsigned int camsize = __ilog2(ram); + unsigned int align = __ffs(virt | phys); + unsigned long max_cam; + + if ((mfspr(SPRN_MMUCFG) & MMUCFG_MAVN) == MMUCFG_MAVN_V1) { + /* Convert (4^max) kB to (2^max) bytes */ + max_cam = ((mfspr(SPRN_TLB1CFG) >> 16) & 0xf) * 2 + 10; + camsize &= ~1U; + align &= ~1U; + } else { + /* Convert (2^max) kB to (2^max) bytes */ + max_cam = __ilog2(mfspr(SPRN_TLB1PS)) + 10; + } + + if (camsize > align) + camsize = align; + if (camsize > max_cam) + camsize = max_cam; + + return 1UL << camsize; +} + +static unsigned long map_mem_in_cams_addr(phys_addr_t phys, unsigned long virt, + unsigned long ram, int max_cam_idx, + bool dryrun, bool init) +{ + int i; + unsigned long amount_mapped = 0; + unsigned long boundary; + + if (strict_kernel_rwx_enabled()) + boundary = (unsigned long)(_sinittext - _stext); + else + boundary = ram; + + /* Calculate CAM values */ + for (i = 0; boundary && i < max_cam_idx; i++) { + unsigned long cam_sz; + pgprot_t prot = init ? PAGE_KERNEL_X : PAGE_KERNEL_ROX; + + cam_sz = calc_cam_sz(boundary, virt, phys); + if (!dryrun) + settlbcam(i, virt, phys, cam_sz, pgprot_val(prot), 0); + + boundary -= cam_sz; + amount_mapped += cam_sz; + virt += cam_sz; + phys += cam_sz; + } + for (ram -= amount_mapped; ram && i < max_cam_idx; i++) { + unsigned long cam_sz; + pgprot_t prot = init ? PAGE_KERNEL_X : PAGE_KERNEL; + + cam_sz = calc_cam_sz(ram, virt, phys); + if (!dryrun) + settlbcam(i, virt, phys, cam_sz, pgprot_val(prot), 0); + + ram -= cam_sz; + amount_mapped += cam_sz; + virt += cam_sz; + phys += cam_sz; + } + + if (dryrun) + return amount_mapped; + + if (init) { + loadcam_multi(0, i, max_cam_idx); + tlbcam_index = i; + } else { + loadcam_multi(0, i, 0); + WARN_ON(i > tlbcam_index); + } + +#ifdef CONFIG_PPC64 + get_paca()->tcd.esel_next = i; + get_paca()->tcd.esel_max = mfspr(SPRN_TLB1CFG) & TLBnCFG_N_ENTRY; + get_paca()->tcd.esel_first = i; +#endif + + return amount_mapped; +} + +unsigned long map_mem_in_cams(unsigned long ram, int max_cam_idx, bool dryrun, bool init) +{ + unsigned long virt = PAGE_OFFSET; + phys_addr_t phys = memstart_addr; + + return map_mem_in_cams_addr(phys, virt, ram, max_cam_idx, dryrun, init); +} + +#ifdef CONFIG_PPC32 + +#if defined(CONFIG_LOWMEM_CAM_NUM_BOOL) && (CONFIG_LOWMEM_CAM_NUM >= NUM_TLBCAMS) +#error "LOWMEM_CAM_NUM must be less than NUM_TLBCAMS" +#endif + +unsigned long __init mmu_mapin_ram(unsigned long base, unsigned long top) +{ + return tlbcam_addrs[tlbcam_index - 1].limit - PAGE_OFFSET + 1; +} + +void flush_instruction_cache(void) +{ + unsigned long tmp; + + tmp = mfspr(SPRN_L1CSR1); + tmp |= L1CSR1_ICFI | L1CSR1_ICLFR; + mtspr(SPRN_L1CSR1, tmp); + isync(); +} + +/* + * MMU_init_hw does the chip-specific initialization of the MMU hardware. + */ +void __init MMU_init_hw(void) +{ + flush_instruction_cache(); +} + +static unsigned long __init tlbcam_sz(int idx) +{ + return tlbcam_addrs[idx].limit - tlbcam_addrs[idx].start + 1; +} + +void __init adjust_total_lowmem(void) +{ + unsigned long ram; + int i; + + /* adjust lowmem size to __max_low_memory */ + ram = min((phys_addr_t)__max_low_memory, (phys_addr_t)total_lowmem); + + i = switch_to_as1(); + __max_low_memory = map_mem_in_cams(ram, CONFIG_LOWMEM_CAM_NUM, false, true); + restore_to_as0(i, 0, NULL, 1); + + pr_info("Memory CAM mapping: "); + for (i = 0; i < tlbcam_index - 1; i++) + pr_cont("%lu/", tlbcam_sz(i) >> 20); + pr_cont("%lu Mb, residual: %dMb\n", tlbcam_sz(tlbcam_index - 1) >> 20, + (unsigned int)((total_lowmem - __max_low_memory) >> 20)); + + memblock_set_current_limit(memstart_addr + __max_low_memory); +} + +#ifdef CONFIG_STRICT_KERNEL_RWX +void mmu_mark_rodata_ro(void) +{ + unsigned long remapped; + + remapped = map_mem_in_cams(__max_low_memory, CONFIG_LOWMEM_CAM_NUM, false, false); + + WARN_ON(__max_low_memory != remapped); +} +#endif + +void mmu_mark_initmem_nx(void) +{ + /* Everything is done in mmu_mark_rodata_ro() */ +} + +void setup_initial_memory_limit(phys_addr_t first_memblock_base, + phys_addr_t first_memblock_size) +{ + phys_addr_t limit = first_memblock_base + first_memblock_size; + + /* 64M mapped initially according to head_fsl_booke.S */ + memblock_set_current_limit(min_t(u64, limit, 0x04000000)); +} + +#ifdef CONFIG_RELOCATABLE +int __initdata is_second_reloc; +notrace void __init relocate_init(u64 dt_ptr, phys_addr_t start) +{ + unsigned long base = kernstart_virt_addr; + phys_addr_t size; + + kernstart_addr = start; + if (is_second_reloc) { + virt_phys_offset = PAGE_OFFSET - memstart_addr; + kaslr_late_init(); + return; + } + + /* + * Relocatable kernel support based on processing of dynamic + * relocation entries. Before we get the real memstart_addr, + * We will compute the virt_phys_offset like this: + * virt_phys_offset = stext.run - kernstart_addr + * + * stext.run = (KERNELBASE & ~0x3ffffff) + + * (kernstart_addr & 0x3ffffff) + * When we relocate, we have : + * + * (kernstart_addr & 0x3ffffff) = (stext.run & 0x3ffffff) + * + * hence: + * virt_phys_offset = (KERNELBASE & ~0x3ffffff) - + * (kernstart_addr & ~0x3ffffff) + * + */ + start &= ~0x3ffffff; + base &= ~0x3ffffff; + virt_phys_offset = base - start; + early_get_first_memblock_info(__va(dt_ptr), &size); + /* + * We now get the memstart_addr, then we should check if this + * address is the same as what the PAGE_OFFSET map to now. If + * not we have to change the map of PAGE_OFFSET to memstart_addr + * and do a second relocation. + */ + if (start != memstart_addr) { + int n; + long offset = start - memstart_addr; + + is_second_reloc = 1; + n = switch_to_as1(); + /* map a 64M area for the second relocation */ + if (memstart_addr > start) + map_mem_in_cams(0x4000000, CONFIG_LOWMEM_CAM_NUM, + false, true); + else + map_mem_in_cams_addr(start, PAGE_OFFSET + offset, + 0x4000000, CONFIG_LOWMEM_CAM_NUM, + false, true); + restore_to_as0(n, offset, __va(dt_ptr), 1); + /* We should never reach here */ + panic("Relocation error"); + } + + kaslr_early_init(__va(dt_ptr), size); +} +#endif +#endif diff --git a/arch/powerpc/mm/nohash/e500_hugetlbpage.c b/arch/powerpc/mm/nohash/e500_hugetlbpage.c new file mode 100644 index 000000000..c7d4b317a --- /dev/null +++ b/arch/powerpc/mm/nohash/e500_hugetlbpage.c @@ -0,0 +1,190 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * PPC Huge TLB Page Support for Book3E MMU + * + * Copyright (C) 2009 David Gibson, IBM Corporation. + * Copyright (C) 2011 Becky Bruce, Freescale Semiconductor + * + */ +#include <linux/mm.h> +#include <linux/hugetlb.h> + +#include <asm/mmu.h> + +#ifdef CONFIG_PPC64 +#include <asm/paca.h> + +static inline int tlb1_next(void) +{ + struct paca_struct *paca = get_paca(); + struct tlb_core_data *tcd; + int this, next; + + tcd = paca->tcd_ptr; + this = tcd->esel_next; + + next = this + 1; + if (next >= tcd->esel_max) + next = tcd->esel_first; + + tcd->esel_next = next; + return this; +} + +static inline void book3e_tlb_lock(void) +{ + struct paca_struct *paca = get_paca(); + unsigned long tmp; + int token = smp_processor_id() + 1; + + /* + * Besides being unnecessary in the absence of SMT, this + * check prevents trying to do lbarx/stbcx. on e5500 which + * doesn't implement either feature. + */ + if (!cpu_has_feature(CPU_FTR_SMT)) + return; + + asm volatile("1: lbarx %0, 0, %1;" + "cmpwi %0, 0;" + "bne 2f;" + "stbcx. %2, 0, %1;" + "bne 1b;" + "b 3f;" + "2: lbzx %0, 0, %1;" + "cmpwi %0, 0;" + "bne 2b;" + "b 1b;" + "3:" + : "=&r" (tmp) + : "r" (&paca->tcd_ptr->lock), "r" (token) + : "memory"); +} + +static inline void book3e_tlb_unlock(void) +{ + struct paca_struct *paca = get_paca(); + + if (!cpu_has_feature(CPU_FTR_SMT)) + return; + + isync(); + paca->tcd_ptr->lock = 0; +} +#else +static inline int tlb1_next(void) +{ + int index, ncams; + + ncams = mfspr(SPRN_TLB1CFG) & TLBnCFG_N_ENTRY; + + index = this_cpu_read(next_tlbcam_idx); + + /* Just round-robin the entries and wrap when we hit the end */ + if (unlikely(index == ncams - 1)) + __this_cpu_write(next_tlbcam_idx, tlbcam_index); + else + __this_cpu_inc(next_tlbcam_idx); + + return index; +} + +static inline void book3e_tlb_lock(void) +{ +} + +static inline void book3e_tlb_unlock(void) +{ +} +#endif + +static inline int book3e_tlb_exists(unsigned long ea, unsigned long pid) +{ + int found = 0; + + mtspr(SPRN_MAS6, pid << 16); + asm volatile( + "tlbsx 0,%1\n" + "mfspr %0,0x271\n" + "srwi %0,%0,31\n" + : "=&r"(found) : "r"(ea)); + + return found; +} + +static void +book3e_hugetlb_preload(struct vm_area_struct *vma, unsigned long ea, pte_t pte) +{ + unsigned long mas1, mas2; + u64 mas7_3; + unsigned long psize, tsize, shift; + unsigned long flags; + struct mm_struct *mm; + int index; + + if (unlikely(is_kernel_addr(ea))) + return; + + mm = vma->vm_mm; + + psize = vma_mmu_pagesize(vma); + shift = __ilog2(psize); + tsize = shift - 10; + /* + * We can't be interrupted while we're setting up the MAS + * registers or after we've confirmed that no tlb exists. + */ + local_irq_save(flags); + + book3e_tlb_lock(); + + if (unlikely(book3e_tlb_exists(ea, mm->context.id))) { + book3e_tlb_unlock(); + local_irq_restore(flags); + return; + } + + /* We have to use the CAM(TLB1) on FSL parts for hugepages */ + index = tlb1_next(); + mtspr(SPRN_MAS0, MAS0_ESEL(index) | MAS0_TLBSEL(1)); + + mas1 = MAS1_VALID | MAS1_TID(mm->context.id) | MAS1_TSIZE(tsize); + mas2 = ea & ~((1UL << shift) - 1); + mas2 |= (pte_val(pte) >> PTE_WIMGE_SHIFT) & MAS2_WIMGE_MASK; + mas7_3 = (u64)pte_pfn(pte) << PAGE_SHIFT; + mas7_3 |= (pte_val(pte) >> PTE_BAP_SHIFT) & MAS3_BAP_MASK; + if (!pte_dirty(pte)) + mas7_3 &= ~(MAS3_SW|MAS3_UW); + + mtspr(SPRN_MAS1, mas1); + mtspr(SPRN_MAS2, mas2); + + if (mmu_has_feature(MMU_FTR_BIG_PHYS)) + mtspr(SPRN_MAS7, upper_32_bits(mas7_3)); + mtspr(SPRN_MAS3, lower_32_bits(mas7_3)); + + asm volatile ("tlbwe"); + + book3e_tlb_unlock(); + local_irq_restore(flags); +} + +/* + * This is called at the end of handling a user page fault, when the + * fault has been handled by updating a PTE in the linux page tables. + * + * This must always be called with the pte lock held. + */ +void update_mmu_cache(struct vm_area_struct *vma, unsigned long address, pte_t *ptep) +{ + if (is_vm_hugetlb_page(vma)) + book3e_hugetlb_preload(vma, address, *ptep); +} + +void flush_hugetlb_page(struct vm_area_struct *vma, unsigned long vmaddr) +{ + struct hstate *hstate = hstate_file(vma->vm_file); + unsigned long tsize = huge_page_shift(hstate) - 10; + + __flush_tlb_page(vma->vm_mm, vmaddr, tsize, 0); +} diff --git a/arch/powerpc/mm/nohash/kaslr_booke.c b/arch/powerpc/mm/nohash/kaslr_booke.c new file mode 100644 index 000000000..0d04f9d5d --- /dev/null +++ b/arch/powerpc/mm/nohash/kaslr_booke.c @@ -0,0 +1,396 @@ +// SPDX-License-Identifier: GPL-2.0-only +// +// Copyright (C) 2019 Jason Yan <yanaijie@huawei.com> + +#include <linux/kernel.h> +#include <linux/errno.h> +#include <linux/string.h> +#include <linux/types.h> +#include <linux/mm.h> +#include <linux/swap.h> +#include <linux/stddef.h> +#include <linux/init.h> +#include <linux/delay.h> +#include <linux/memblock.h> +#include <linux/libfdt.h> +#include <linux/crash_core.h> +#include <linux/of.h> +#include <linux/of_fdt.h> +#include <asm/cacheflush.h> +#include <asm/kdump.h> +#include <mm/mmu_decl.h> +#include <generated/utsrelease.h> + +struct regions { + unsigned long pa_start; + unsigned long pa_end; + unsigned long kernel_size; + unsigned long dtb_start; + unsigned long dtb_end; + unsigned long initrd_start; + unsigned long initrd_end; + unsigned long crash_start; + unsigned long crash_end; + int reserved_mem; + int reserved_mem_addr_cells; + int reserved_mem_size_cells; +}; + +struct regions __initdata regions; + +static __init void kaslr_get_cmdline(void *fdt) +{ + early_init_dt_scan_chosen(boot_command_line); +} + +static unsigned long __init rotate_xor(unsigned long hash, const void *area, + size_t size) +{ + size_t i; + const unsigned long *ptr = area; + + for (i = 0; i < size / sizeof(hash); i++) { + /* Rotate by odd number of bits and XOR. */ + hash = (hash << ((sizeof(hash) * 8) - 7)) | (hash >> 7); + hash ^= ptr[i]; + } + + return hash; +} + +/* Attempt to create a simple starting entropy. This can make it defferent for + * every build but it is still not enough. Stronger entropy should + * be added to make it change for every boot. + */ +static unsigned long __init get_boot_seed(void *fdt) +{ + unsigned long hash = 0; + + /* build-specific string for starting entropy. */ + hash = rotate_xor(hash, linux_banner, strlen(linux_banner)); + hash = rotate_xor(hash, fdt, fdt_totalsize(fdt)); + + return hash; +} + +static __init u64 get_kaslr_seed(void *fdt) +{ + int node, len; + fdt64_t *prop; + u64 ret; + + node = fdt_path_offset(fdt, "/chosen"); + if (node < 0) + return 0; + + prop = fdt_getprop_w(fdt, node, "kaslr-seed", &len); + if (!prop || len != sizeof(u64)) + return 0; + + ret = fdt64_to_cpu(*prop); + *prop = 0; + return ret; +} + +static __init bool regions_overlap(u32 s1, u32 e1, u32 s2, u32 e2) +{ + return e1 >= s2 && e2 >= s1; +} + +static __init bool overlaps_reserved_region(const void *fdt, u32 start, + u32 end) +{ + int subnode, len, i; + u64 base, size; + + /* check for overlap with /memreserve/ entries */ + for (i = 0; i < fdt_num_mem_rsv(fdt); i++) { + if (fdt_get_mem_rsv(fdt, i, &base, &size) < 0) + continue; + if (regions_overlap(start, end, base, base + size)) + return true; + } + + if (regions.reserved_mem < 0) + return false; + + /* check for overlap with static reservations in /reserved-memory */ + for (subnode = fdt_first_subnode(fdt, regions.reserved_mem); + subnode >= 0; + subnode = fdt_next_subnode(fdt, subnode)) { + const fdt32_t *reg; + u64 rsv_end; + + len = 0; + reg = fdt_getprop(fdt, subnode, "reg", &len); + while (len >= (regions.reserved_mem_addr_cells + + regions.reserved_mem_size_cells)) { + base = fdt32_to_cpu(reg[0]); + if (regions.reserved_mem_addr_cells == 2) + base = (base << 32) | fdt32_to_cpu(reg[1]); + + reg += regions.reserved_mem_addr_cells; + len -= 4 * regions.reserved_mem_addr_cells; + + size = fdt32_to_cpu(reg[0]); + if (regions.reserved_mem_size_cells == 2) + size = (size << 32) | fdt32_to_cpu(reg[1]); + + reg += regions.reserved_mem_size_cells; + len -= 4 * regions.reserved_mem_size_cells; + + if (base >= regions.pa_end) + continue; + + rsv_end = min(base + size, (u64)U32_MAX); + + if (regions_overlap(start, end, base, rsv_end)) + return true; + } + } + return false; +} + +static __init bool overlaps_region(const void *fdt, u32 start, + u32 end) +{ + if (regions_overlap(start, end, __pa(_stext), __pa(_end))) + return true; + + if (regions_overlap(start, end, regions.dtb_start, + regions.dtb_end)) + return true; + + if (regions_overlap(start, end, regions.initrd_start, + regions.initrd_end)) + return true; + + if (regions_overlap(start, end, regions.crash_start, + regions.crash_end)) + return true; + + return overlaps_reserved_region(fdt, start, end); +} + +static void __init get_crash_kernel(void *fdt, unsigned long size) +{ +#ifdef CONFIG_CRASH_CORE + unsigned long long crash_size, crash_base; + int ret; + + ret = parse_crashkernel(boot_command_line, size, &crash_size, + &crash_base); + if (ret != 0 || crash_size == 0) + return; + if (crash_base == 0) + crash_base = KDUMP_KERNELBASE; + + regions.crash_start = (unsigned long)crash_base; + regions.crash_end = (unsigned long)(crash_base + crash_size); + + pr_debug("crash_base=0x%llx crash_size=0x%llx\n", crash_base, crash_size); +#endif +} + +static void __init get_initrd_range(void *fdt) +{ + u64 start, end; + int node, len; + const __be32 *prop; + + node = fdt_path_offset(fdt, "/chosen"); + if (node < 0) + return; + + prop = fdt_getprop(fdt, node, "linux,initrd-start", &len); + if (!prop) + return; + start = of_read_number(prop, len / 4); + + prop = fdt_getprop(fdt, node, "linux,initrd-end", &len); + if (!prop) + return; + end = of_read_number(prop, len / 4); + + regions.initrd_start = (unsigned long)start; + regions.initrd_end = (unsigned long)end; + + pr_debug("initrd_start=0x%llx initrd_end=0x%llx\n", start, end); +} + +static __init unsigned long get_usable_address(const void *fdt, + unsigned long start, + unsigned long offset) +{ + unsigned long pa; + unsigned long pa_end; + + for (pa = offset; (long)pa > (long)start; pa -= SZ_16K) { + pa_end = pa + regions.kernel_size; + if (overlaps_region(fdt, pa, pa_end)) + continue; + + return pa; + } + return 0; +} + +static __init void get_cell_sizes(const void *fdt, int node, int *addr_cells, + int *size_cells) +{ + const int *prop; + int len; + + /* + * Retrieve the #address-cells and #size-cells properties + * from the 'node', or use the default if not provided. + */ + *addr_cells = *size_cells = 1; + + prop = fdt_getprop(fdt, node, "#address-cells", &len); + if (len == 4) + *addr_cells = fdt32_to_cpu(*prop); + prop = fdt_getprop(fdt, node, "#size-cells", &len); + if (len == 4) + *size_cells = fdt32_to_cpu(*prop); +} + +static unsigned long __init kaslr_legal_offset(void *dt_ptr, unsigned long index, + unsigned long offset) +{ + unsigned long koffset = 0; + unsigned long start; + + while ((long)index >= 0) { + offset = memstart_addr + index * SZ_64M + offset; + start = memstart_addr + index * SZ_64M; + koffset = get_usable_address(dt_ptr, start, offset); + if (koffset) + break; + index--; + } + + if (koffset != 0) + koffset -= memstart_addr; + + return koffset; +} + +static inline __init bool kaslr_disabled(void) +{ + return strstr(boot_command_line, "nokaslr") != NULL; +} + +static unsigned long __init kaslr_choose_location(void *dt_ptr, phys_addr_t size, + unsigned long kernel_sz) +{ + unsigned long offset, random; + unsigned long ram, linear_sz; + u64 seed; + unsigned long index; + + kaslr_get_cmdline(dt_ptr); + if (kaslr_disabled()) + return 0; + + random = get_boot_seed(dt_ptr); + + seed = get_tb() << 32; + seed ^= get_tb(); + random = rotate_xor(random, &seed, sizeof(seed)); + + /* + * Retrieve (and wipe) the seed from the FDT + */ + seed = get_kaslr_seed(dt_ptr); + if (seed) + random = rotate_xor(random, &seed, sizeof(seed)); + else + pr_warn("KASLR: No safe seed for randomizing the kernel base.\n"); + + ram = min_t(phys_addr_t, __max_low_memory, size); + ram = map_mem_in_cams(ram, CONFIG_LOWMEM_CAM_NUM, true, true); + linear_sz = min_t(unsigned long, ram, SZ_512M); + + /* If the linear size is smaller than 64M, do not randomize */ + if (linear_sz < SZ_64M) + return 0; + + /* check for a reserved-memory node and record its cell sizes */ + regions.reserved_mem = fdt_path_offset(dt_ptr, "/reserved-memory"); + if (regions.reserved_mem >= 0) + get_cell_sizes(dt_ptr, regions.reserved_mem, + ®ions.reserved_mem_addr_cells, + ®ions.reserved_mem_size_cells); + + regions.pa_start = memstart_addr; + regions.pa_end = memstart_addr + linear_sz; + regions.dtb_start = __pa(dt_ptr); + regions.dtb_end = __pa(dt_ptr) + fdt_totalsize(dt_ptr); + regions.kernel_size = kernel_sz; + + get_initrd_range(dt_ptr); + get_crash_kernel(dt_ptr, ram); + + /* + * Decide which 64M we want to start + * Only use the low 8 bits of the random seed + */ + index = random & 0xFF; + index %= linear_sz / SZ_64M; + + /* Decide offset inside 64M */ + offset = random % (SZ_64M - kernel_sz); + offset = round_down(offset, SZ_16K); + + return kaslr_legal_offset(dt_ptr, index, offset); +} + +/* + * To see if we need to relocate the kernel to a random offset + * void *dt_ptr - address of the device tree + * phys_addr_t size - size of the first memory block + */ +notrace void __init kaslr_early_init(void *dt_ptr, phys_addr_t size) +{ + unsigned long tlb_virt; + phys_addr_t tlb_phys; + unsigned long offset; + unsigned long kernel_sz; + + kernel_sz = (unsigned long)_end - (unsigned long)_stext; + + offset = kaslr_choose_location(dt_ptr, size, kernel_sz); + if (offset == 0) + return; + + kernstart_virt_addr += offset; + kernstart_addr += offset; + + is_second_reloc = 1; + + if (offset >= SZ_64M) { + tlb_virt = round_down(kernstart_virt_addr, SZ_64M); + tlb_phys = round_down(kernstart_addr, SZ_64M); + + /* Create kernel map to relocate in */ + create_kaslr_tlb_entry(1, tlb_virt, tlb_phys); + } + + /* Copy the kernel to it's new location and run */ + memcpy((void *)kernstart_virt_addr, (void *)_stext, kernel_sz); + flush_icache_range(kernstart_virt_addr, kernstart_virt_addr + kernel_sz); + + reloc_kernel_entry(dt_ptr, kernstart_virt_addr); +} + +void __init kaslr_late_init(void) +{ + /* If randomized, clear the original kernel */ + if (kernstart_virt_addr != KERNELBASE) { + unsigned long kernel_sz; + + kernel_sz = (unsigned long)_end - kernstart_virt_addr; + memzero_explicit((void *)KERNELBASE, kernel_sz); + } +} diff --git a/arch/powerpc/mm/nohash/kup.c b/arch/powerpc/mm/nohash/kup.c new file mode 100644 index 000000000..552becf90 --- /dev/null +++ b/arch/powerpc/mm/nohash/kup.c @@ -0,0 +1,33 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * This file contains the routines for initializing kernel userspace protection + */ + +#include <linux/export.h> +#include <linux/init.h> +#include <linux/jump_label.h> +#include <linux/printk.h> +#include <linux/smp.h> + +#include <asm/kup.h> +#include <asm/smp.h> + +#ifdef CONFIG_PPC_KUAP +struct static_key_false disable_kuap_key; +EXPORT_SYMBOL(disable_kuap_key); + +void setup_kuap(bool disabled) +{ + if (disabled) { + if (IS_ENABLED(CONFIG_40x)) + disable_kuep = true; + if (smp_processor_id() == boot_cpuid) + static_branch_enable(&disable_kuap_key); + return; + } + + pr_info("Activating Kernel Userspace Access Protection\n"); + + __prevent_user_access(KUAP_READ_WRITE); +} +#endif diff --git a/arch/powerpc/mm/nohash/mmu_context.c b/arch/powerpc/mm/nohash/mmu_context.c new file mode 100644 index 000000000..ccd5819b1 --- /dev/null +++ b/arch/powerpc/mm/nohash/mmu_context.c @@ -0,0 +1,425 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * This file contains the routines for handling the MMU on those + * PowerPC implementations where the MMU is not using the hash + * table, such as 8xx, 4xx, BookE's etc... + * + * Copyright 2008 Ben Herrenschmidt <benh@kernel.crashing.org> + * IBM Corp. + * + * Derived from previous arch/powerpc/mm/mmu_context.c + * and arch/powerpc/include/asm/mmu_context.h + * + * TODO: + * + * - The global context lock will not scale very well + * - The maps should be dynamically allocated to allow for processors + * that support more PID bits at runtime + * - Implement flush_tlb_mm() by making the context stale and picking + * a new one + * - More aggressively clear stale map bits and maybe find some way to + * also clear mm->cpu_vm_mask bits when processes are migrated + */ + +#include <linux/kernel.h> +#include <linux/mm.h> +#include <linux/init.h> +#include <linux/spinlock.h> +#include <linux/memblock.h> +#include <linux/notifier.h> +#include <linux/cpu.h> +#include <linux/slab.h> + +#include <asm/mmu_context.h> +#include <asm/tlbflush.h> +#include <asm/smp.h> +#include <asm/kup.h> + +#include <mm/mmu_decl.h> + +/* + * Room for two PTE table pointers, usually the kernel and current user + * pointer to their respective root page table (pgdir). + */ +void *abatron_pteptrs[2]; + +/* + * The MPC8xx has only 16 contexts. We rotate through them on each task switch. + * A better way would be to keep track of tasks that own contexts, and implement + * an LRU usage. That way very active tasks don't always have to pay the TLB + * reload overhead. The kernel pages are mapped shared, so the kernel can run on + * behalf of any task that makes a kernel entry. Shared does not mean they are + * not protected, just that the ASID comparison is not performed. -- Dan + * + * The IBM4xx has 256 contexts, so we can just rotate through these as a way of + * "switching" contexts. If the TID of the TLB is zero, the PID/TID comparison + * is disabled, so we can use a TID of zero to represent all kernel pages as + * shared among all contexts. -- Dan + * + * The IBM 47x core supports 16-bit PIDs, thus 65535 contexts. We should + * normally never have to steal though the facility is present if needed. + * -- BenH + */ +#define FIRST_CONTEXT 1 +#if defined(CONFIG_PPC_8xx) +#define LAST_CONTEXT 16 +#elif defined(CONFIG_PPC_47x) +#define LAST_CONTEXT 65535 +#else +#define LAST_CONTEXT 255 +#endif + +static unsigned int next_context, nr_free_contexts; +static unsigned long *context_map; +static unsigned long *stale_map[NR_CPUS]; +static struct mm_struct **context_mm; +static DEFINE_RAW_SPINLOCK(context_lock); + +#define CTX_MAP_SIZE \ + (sizeof(unsigned long) * (LAST_CONTEXT / BITS_PER_LONG + 1)) + + +/* Steal a context from a task that has one at the moment. + * + * This is used when we are running out of available PID numbers + * on the processors. + * + * This isn't an LRU system, it just frees up each context in + * turn (sort-of pseudo-random replacement :). This would be the + * place to implement an LRU scheme if anyone was motivated to do it. + * -- paulus + * + * For context stealing, we use a slightly different approach for + * SMP and UP. Basically, the UP one is simpler and doesn't use + * the stale map as we can just flush the local CPU + * -- benh + */ +static unsigned int steal_context_smp(unsigned int id) +{ + struct mm_struct *mm; + unsigned int cpu, max, i; + + max = LAST_CONTEXT - FIRST_CONTEXT; + + /* Attempt to free next_context first and then loop until we manage */ + while (max--) { + /* Pick up the victim mm */ + mm = context_mm[id]; + + /* We have a candidate victim, check if it's active, on SMP + * we cannot steal active contexts + */ + if (mm->context.active) { + id++; + if (id > LAST_CONTEXT) + id = FIRST_CONTEXT; + continue; + } + + /* Mark this mm has having no context anymore */ + mm->context.id = MMU_NO_CONTEXT; + + /* Mark it stale on all CPUs that used this mm. For threaded + * implementations, we set it on all threads on each core + * represented in the mask. A future implementation will use + * a core map instead but this will do for now. + */ + for_each_cpu(cpu, mm_cpumask(mm)) { + for (i = cpu_first_thread_sibling(cpu); + i <= cpu_last_thread_sibling(cpu); i++) { + if (stale_map[i]) + __set_bit(id, stale_map[i]); + } + cpu = i - 1; + } + return id; + } + + /* This will happen if you have more CPUs than available contexts, + * all we can do here is wait a bit and try again + */ + raw_spin_unlock(&context_lock); + cpu_relax(); + raw_spin_lock(&context_lock); + + /* This will cause the caller to try again */ + return MMU_NO_CONTEXT; +} + +static unsigned int steal_all_contexts(void) +{ + struct mm_struct *mm; + int cpu = smp_processor_id(); + unsigned int id; + + for (id = FIRST_CONTEXT; id <= LAST_CONTEXT; id++) { + /* Pick up the victim mm */ + mm = context_mm[id]; + + /* Mark this mm as having no context anymore */ + mm->context.id = MMU_NO_CONTEXT; + if (id != FIRST_CONTEXT) { + context_mm[id] = NULL; + __clear_bit(id, context_map); + } + if (IS_ENABLED(CONFIG_SMP)) + __clear_bit(id, stale_map[cpu]); + } + + /* Flush the TLB for all contexts (not to be used on SMP) */ + _tlbil_all(); + + nr_free_contexts = LAST_CONTEXT - FIRST_CONTEXT; + + return FIRST_CONTEXT; +} + +/* Note that this will also be called on SMP if all other CPUs are + * offlined, which means that it may be called for cpu != 0. For + * this to work, we somewhat assume that CPUs that are onlined + * come up with a fully clean TLB (or are cleaned when offlined) + */ +static unsigned int steal_context_up(unsigned int id) +{ + struct mm_struct *mm; + int cpu = smp_processor_id(); + + /* Pick up the victim mm */ + mm = context_mm[id]; + + /* Flush the TLB for that context */ + local_flush_tlb_mm(mm); + + /* Mark this mm has having no context anymore */ + mm->context.id = MMU_NO_CONTEXT; + + /* XXX This clear should ultimately be part of local_flush_tlb_mm */ + if (IS_ENABLED(CONFIG_SMP)) + __clear_bit(id, stale_map[cpu]); + + return id; +} + +static void set_context(unsigned long id, pgd_t *pgd) +{ + if (IS_ENABLED(CONFIG_PPC_8xx)) { + s16 offset = (s16)(__pa(swapper_pg_dir)); + + /* + * Register M_TWB will contain base address of level 1 table minus the + * lower part of the kernel PGDIR base address, so that all accesses to + * level 1 table are done relative to lower part of kernel PGDIR base + * address. + */ + mtspr(SPRN_M_TWB, __pa(pgd) - offset); + + /* Update context */ + mtspr(SPRN_M_CASID, id - 1); + + /* sync */ + mb(); + } else if (kuap_is_disabled()) { + if (IS_ENABLED(CONFIG_40x)) + mb(); /* sync */ + + mtspr(SPRN_PID, id); + isync(); + } +} + +void switch_mmu_context(struct mm_struct *prev, struct mm_struct *next, + struct task_struct *tsk) +{ + unsigned int id; + unsigned int i, cpu = smp_processor_id(); + unsigned long *map; + + /* No lockless fast path .. yet */ + raw_spin_lock(&context_lock); + + if (IS_ENABLED(CONFIG_SMP)) { + /* Mark us active and the previous one not anymore */ + next->context.active++; + if (prev) { + WARN_ON(prev->context.active < 1); + prev->context.active--; + } + } + + again: + + /* If we already have a valid assigned context, skip all that */ + id = next->context.id; + if (likely(id != MMU_NO_CONTEXT)) + goto ctxt_ok; + + /* We really don't have a context, let's try to acquire one */ + id = next_context; + if (id > LAST_CONTEXT) + id = FIRST_CONTEXT; + map = context_map; + + /* No more free contexts, let's try to steal one */ + if (nr_free_contexts == 0) { + if (num_online_cpus() > 1) { + id = steal_context_smp(id); + if (id == MMU_NO_CONTEXT) + goto again; + goto stolen; + } + if (IS_ENABLED(CONFIG_PPC_8xx)) + id = steal_all_contexts(); + else + id = steal_context_up(id); + goto stolen; + } + nr_free_contexts--; + + /* We know there's at least one free context, try to find it */ + while (__test_and_set_bit(id, map)) { + id = find_next_zero_bit(map, LAST_CONTEXT+1, id); + if (id > LAST_CONTEXT) + id = FIRST_CONTEXT; + } + stolen: + next_context = id + 1; + context_mm[id] = next; + next->context.id = id; + + ctxt_ok: + + /* If that context got marked stale on this CPU, then flush the + * local TLB for it and unmark it before we use it + */ + if (IS_ENABLED(CONFIG_SMP) && test_bit(id, stale_map[cpu])) { + local_flush_tlb_mm(next); + + /* XXX This clear should ultimately be part of local_flush_tlb_mm */ + for (i = cpu_first_thread_sibling(cpu); + i <= cpu_last_thread_sibling(cpu); i++) { + if (stale_map[i]) + __clear_bit(id, stale_map[i]); + } + } + + /* Flick the MMU and release lock */ + if (IS_ENABLED(CONFIG_BDI_SWITCH)) + abatron_pteptrs[1] = next->pgd; + set_context(id, next->pgd); +#if defined(CONFIG_BOOKE_OR_40x) && defined(CONFIG_PPC_KUAP) + tsk->thread.pid = id; +#endif + raw_spin_unlock(&context_lock); +} + +/* + * Set up the context for a new address space. + */ +int init_new_context(struct task_struct *t, struct mm_struct *mm) +{ + mm->context.id = MMU_NO_CONTEXT; + mm->context.active = 0; + pte_frag_set(&mm->context, NULL); + return 0; +} + +/* + * We're finished using the context for an address space. + */ +void destroy_context(struct mm_struct *mm) +{ + unsigned long flags; + unsigned int id; + + if (mm->context.id == MMU_NO_CONTEXT) + return; + + WARN_ON(mm->context.active != 0); + + raw_spin_lock_irqsave(&context_lock, flags); + id = mm->context.id; + if (id != MMU_NO_CONTEXT) { + __clear_bit(id, context_map); + mm->context.id = MMU_NO_CONTEXT; + context_mm[id] = NULL; + nr_free_contexts++; + } + raw_spin_unlock_irqrestore(&context_lock, flags); +} + +static int mmu_ctx_cpu_prepare(unsigned int cpu) +{ + /* We don't touch CPU 0 map, it's allocated at aboot and kept + * around forever + */ + if (cpu == boot_cpuid) + return 0; + + stale_map[cpu] = kzalloc(CTX_MAP_SIZE, GFP_KERNEL); + return 0; +} + +static int mmu_ctx_cpu_dead(unsigned int cpu) +{ +#ifdef CONFIG_HOTPLUG_CPU + if (cpu == boot_cpuid) + return 0; + + kfree(stale_map[cpu]); + stale_map[cpu] = NULL; + + /* We also clear the cpu_vm_mask bits of CPUs going away */ + clear_tasks_mm_cpumask(cpu); +#endif + return 0; +} + +/* + * Initialize the context management stuff. + */ +void __init mmu_context_init(void) +{ + /* Mark init_mm as being active on all possible CPUs since + * we'll get called with prev == init_mm the first time + * we schedule on a given CPU + */ + init_mm.context.active = NR_CPUS; + + /* + * Allocate the maps used by context management + */ + context_map = memblock_alloc(CTX_MAP_SIZE, SMP_CACHE_BYTES); + if (!context_map) + panic("%s: Failed to allocate %zu bytes\n", __func__, + CTX_MAP_SIZE); + context_mm = memblock_alloc(sizeof(void *) * (LAST_CONTEXT + 1), + SMP_CACHE_BYTES); + if (!context_mm) + panic("%s: Failed to allocate %zu bytes\n", __func__, + sizeof(void *) * (LAST_CONTEXT + 1)); + if (IS_ENABLED(CONFIG_SMP)) { + stale_map[boot_cpuid] = memblock_alloc(CTX_MAP_SIZE, SMP_CACHE_BYTES); + if (!stale_map[boot_cpuid]) + panic("%s: Failed to allocate %zu bytes\n", __func__, + CTX_MAP_SIZE); + + cpuhp_setup_state_nocalls(CPUHP_POWERPC_MMU_CTX_PREPARE, + "powerpc/mmu/ctx:prepare", + mmu_ctx_cpu_prepare, mmu_ctx_cpu_dead); + } + + printk(KERN_INFO + "MMU: Allocated %zu bytes of context maps for %d contexts\n", + 2 * CTX_MAP_SIZE + (sizeof(void *) * (LAST_CONTEXT + 1)), + LAST_CONTEXT - FIRST_CONTEXT + 1); + + /* + * Some processors have too few contexts to reserve one for + * init_mm, and require using context 0 for a normal task. + * Other processors reserve the use of context zero for the kernel. + * This code assumes FIRST_CONTEXT < 32. + */ + context_map[0] = (1 << FIRST_CONTEXT) - 1; + next_context = FIRST_CONTEXT; + nr_free_contexts = LAST_CONTEXT - FIRST_CONTEXT + 1; +} diff --git a/arch/powerpc/mm/nohash/tlb.c b/arch/powerpc/mm/nohash/tlb.c new file mode 100644 index 000000000..2c15c86c7 --- /dev/null +++ b/arch/powerpc/mm/nohash/tlb.c @@ -0,0 +1,745 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * This file contains the routines for TLB flushing. + * On machines where the MMU does not use a hash table to store virtual to + * physical translations (ie, SW loaded TLBs or Book3E compilant processors, + * this does -not- include 603 however which shares the implementation with + * hash based processors) + * + * -- BenH + * + * Copyright 2008,2009 Ben Herrenschmidt <benh@kernel.crashing.org> + * IBM Corp. + * + * Derived from arch/ppc/mm/init.c: + * Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org) + * + * Modifications by Paul Mackerras (PowerMac) (paulus@cs.anu.edu.au) + * and Cort Dougan (PReP) (cort@cs.nmt.edu) + * Copyright (C) 1996 Paul Mackerras + * + * Derived from "arch/i386/mm/init.c" + * Copyright (C) 1991, 1992, 1993, 1994 Linus Torvalds + */ + +#include <linux/kernel.h> +#include <linux/export.h> +#include <linux/mm.h> +#include <linux/init.h> +#include <linux/highmem.h> +#include <linux/pagemap.h> +#include <linux/preempt.h> +#include <linux/spinlock.h> +#include <linux/memblock.h> +#include <linux/of_fdt.h> +#include <linux/hugetlb.h> + +#include <asm/pgalloc.h> +#include <asm/tlbflush.h> +#include <asm/tlb.h> +#include <asm/code-patching.h> +#include <asm/cputhreads.h> +#include <asm/hugetlb.h> +#include <asm/paca.h> + +#include <mm/mmu_decl.h> + +/* + * This struct lists the sw-supported page sizes. The hardawre MMU may support + * other sizes not listed here. The .ind field is only used on MMUs that have + * indirect page table entries. + */ +#ifdef CONFIG_PPC_E500 +struct mmu_psize_def mmu_psize_defs[MMU_PAGE_COUNT] = { + [MMU_PAGE_4K] = { + .shift = 12, + .enc = BOOK3E_PAGESZ_4K, + }, + [MMU_PAGE_2M] = { + .shift = 21, + .enc = BOOK3E_PAGESZ_2M, + }, + [MMU_PAGE_4M] = { + .shift = 22, + .enc = BOOK3E_PAGESZ_4M, + }, + [MMU_PAGE_16M] = { + .shift = 24, + .enc = BOOK3E_PAGESZ_16M, + }, + [MMU_PAGE_64M] = { + .shift = 26, + .enc = BOOK3E_PAGESZ_64M, + }, + [MMU_PAGE_256M] = { + .shift = 28, + .enc = BOOK3E_PAGESZ_256M, + }, + [MMU_PAGE_1G] = { + .shift = 30, + .enc = BOOK3E_PAGESZ_1GB, + }, +}; + +static inline int mmu_get_tsize(int psize) +{ + return mmu_psize_defs[psize].enc; +} +#else +static inline int mmu_get_tsize(int psize) +{ + /* This isn't used on !Book3E for now */ + return 0; +} +#endif + +#ifdef CONFIG_PPC_8xx +struct mmu_psize_def mmu_psize_defs[MMU_PAGE_COUNT] = { + [MMU_PAGE_4K] = { + .shift = 12, + }, + [MMU_PAGE_16K] = { + .shift = 14, + }, + [MMU_PAGE_512K] = { + .shift = 19, + }, + [MMU_PAGE_8M] = { + .shift = 23, + }, +}; +#endif + +/* The variables below are currently only used on 64-bit Book3E + * though this will probably be made common with other nohash + * implementations at some point + */ +#ifdef CONFIG_PPC64 + +int mmu_pte_psize; /* Page size used for PTE pages */ +int mmu_vmemmap_psize; /* Page size used for the virtual mem map */ +int book3e_htw_mode; /* HW tablewalk? Value is PPC_HTW_* */ +unsigned long linear_map_top; /* Top of linear mapping */ + + +/* + * Number of bytes to add to SPRN_SPRG_TLB_EXFRAME on crit/mcheck/debug + * exceptions. This is used for bolted and e6500 TLB miss handlers which + * do not modify this SPRG in the TLB miss code; for other TLB miss handlers, + * this is set to zero. + */ +int extlb_level_exc; + +#endif /* CONFIG_PPC64 */ + +#ifdef CONFIG_PPC_E500 +/* next_tlbcam_idx is used to round-robin tlbcam entry assignment */ +DEFINE_PER_CPU(int, next_tlbcam_idx); +EXPORT_PER_CPU_SYMBOL(next_tlbcam_idx); +#endif + +/* + * Base TLB flushing operations: + * + * - flush_tlb_mm(mm) flushes the specified mm context TLB's + * - flush_tlb_page(vma, vmaddr) flushes one page + * - flush_tlb_range(vma, start, end) flushes a range of pages + * - flush_tlb_kernel_range(start, end) flushes kernel pages + * + * - local_* variants of page and mm only apply to the current + * processor + */ + +#ifndef CONFIG_PPC_8xx +/* + * These are the base non-SMP variants of page and mm flushing + */ +void local_flush_tlb_mm(struct mm_struct *mm) +{ + unsigned int pid; + + preempt_disable(); + pid = mm->context.id; + if (pid != MMU_NO_CONTEXT) + _tlbil_pid(pid); + preempt_enable(); +} +EXPORT_SYMBOL(local_flush_tlb_mm); + +void __local_flush_tlb_page(struct mm_struct *mm, unsigned long vmaddr, + int tsize, int ind) +{ + unsigned int pid; + + preempt_disable(); + pid = mm ? mm->context.id : 0; + if (pid != MMU_NO_CONTEXT) + _tlbil_va(vmaddr, pid, tsize, ind); + preempt_enable(); +} + +void local_flush_tlb_page(struct vm_area_struct *vma, unsigned long vmaddr) +{ + __local_flush_tlb_page(vma ? vma->vm_mm : NULL, vmaddr, + mmu_get_tsize(mmu_virtual_psize), 0); +} +EXPORT_SYMBOL(local_flush_tlb_page); +#endif + +/* + * And here are the SMP non-local implementations + */ +#ifdef CONFIG_SMP + +static DEFINE_RAW_SPINLOCK(tlbivax_lock); + +struct tlb_flush_param { + unsigned long addr; + unsigned int pid; + unsigned int tsize; + unsigned int ind; +}; + +static void do_flush_tlb_mm_ipi(void *param) +{ + struct tlb_flush_param *p = param; + + _tlbil_pid(p ? p->pid : 0); +} + +static void do_flush_tlb_page_ipi(void *param) +{ + struct tlb_flush_param *p = param; + + _tlbil_va(p->addr, p->pid, p->tsize, p->ind); +} + + +/* Note on invalidations and PID: + * + * We snapshot the PID with preempt disabled. At this point, it can still + * change either because: + * - our context is being stolen (PID -> NO_CONTEXT) on another CPU + * - we are invaliating some target that isn't currently running here + * and is concurrently acquiring a new PID on another CPU + * - some other CPU is re-acquiring a lost PID for this mm + * etc... + * + * However, this shouldn't be a problem as we only guarantee + * invalidation of TLB entries present prior to this call, so we + * don't care about the PID changing, and invalidating a stale PID + * is generally harmless. + */ + +void flush_tlb_mm(struct mm_struct *mm) +{ + unsigned int pid; + + preempt_disable(); + pid = mm->context.id; + if (unlikely(pid == MMU_NO_CONTEXT)) + goto no_context; + if (!mm_is_core_local(mm)) { + struct tlb_flush_param p = { .pid = pid }; + /* Ignores smp_processor_id() even if set. */ + smp_call_function_many(mm_cpumask(mm), + do_flush_tlb_mm_ipi, &p, 1); + } + _tlbil_pid(pid); + no_context: + preempt_enable(); +} +EXPORT_SYMBOL(flush_tlb_mm); + +void __flush_tlb_page(struct mm_struct *mm, unsigned long vmaddr, + int tsize, int ind) +{ + struct cpumask *cpu_mask; + unsigned int pid; + + /* + * This function as well as __local_flush_tlb_page() must only be called + * for user contexts. + */ + if (WARN_ON(!mm)) + return; + + preempt_disable(); + pid = mm->context.id; + if (unlikely(pid == MMU_NO_CONTEXT)) + goto bail; + cpu_mask = mm_cpumask(mm); + if (!mm_is_core_local(mm)) { + /* If broadcast tlbivax is supported, use it */ + if (mmu_has_feature(MMU_FTR_USE_TLBIVAX_BCAST)) { + int lock = mmu_has_feature(MMU_FTR_LOCK_BCAST_INVAL); + if (lock) + raw_spin_lock(&tlbivax_lock); + _tlbivax_bcast(vmaddr, pid, tsize, ind); + if (lock) + raw_spin_unlock(&tlbivax_lock); + goto bail; + } else { + struct tlb_flush_param p = { + .pid = pid, + .addr = vmaddr, + .tsize = tsize, + .ind = ind, + }; + /* Ignores smp_processor_id() even if set in cpu_mask */ + smp_call_function_many(cpu_mask, + do_flush_tlb_page_ipi, &p, 1); + } + } + _tlbil_va(vmaddr, pid, tsize, ind); + bail: + preempt_enable(); +} + +void flush_tlb_page(struct vm_area_struct *vma, unsigned long vmaddr) +{ +#ifdef CONFIG_HUGETLB_PAGE + if (vma && is_vm_hugetlb_page(vma)) + flush_hugetlb_page(vma, vmaddr); +#endif + + __flush_tlb_page(vma ? vma->vm_mm : NULL, vmaddr, + mmu_get_tsize(mmu_virtual_psize), 0); +} +EXPORT_SYMBOL(flush_tlb_page); + +#endif /* CONFIG_SMP */ + +#ifdef CONFIG_PPC_47x +void __init early_init_mmu_47x(void) +{ +#ifdef CONFIG_SMP + unsigned long root = of_get_flat_dt_root(); + if (of_get_flat_dt_prop(root, "cooperative-partition", NULL)) + mmu_clear_feature(MMU_FTR_USE_TLBIVAX_BCAST); +#endif /* CONFIG_SMP */ +} +#endif /* CONFIG_PPC_47x */ + +/* + * Flush kernel TLB entries in the given range + */ +#ifndef CONFIG_PPC_8xx +void flush_tlb_kernel_range(unsigned long start, unsigned long end) +{ +#ifdef CONFIG_SMP + preempt_disable(); + smp_call_function(do_flush_tlb_mm_ipi, NULL, 1); + _tlbil_pid(0); + preempt_enable(); +#else + _tlbil_pid(0); +#endif +} +EXPORT_SYMBOL(flush_tlb_kernel_range); +#endif + +/* + * Currently, for range flushing, we just do a full mm flush. This should + * be optimized based on a threshold on the size of the range, since + * some implementation can stack multiple tlbivax before a tlbsync but + * for now, we keep it that way + */ +void flush_tlb_range(struct vm_area_struct *vma, unsigned long start, + unsigned long end) + +{ + if (end - start == PAGE_SIZE && !(start & ~PAGE_MASK)) + flush_tlb_page(vma, start); + else + flush_tlb_mm(vma->vm_mm); +} +EXPORT_SYMBOL(flush_tlb_range); + +void tlb_flush(struct mmu_gather *tlb) +{ + flush_tlb_mm(tlb->mm); +} + +/* + * Below are functions specific to the 64-bit variant of Book3E though that + * may change in the future + */ + +#ifdef CONFIG_PPC64 + +/* + * Handling of virtual linear page tables or indirect TLB entries + * flushing when PTE pages are freed + */ +void tlb_flush_pgtable(struct mmu_gather *tlb, unsigned long address) +{ + int tsize = mmu_psize_defs[mmu_pte_psize].enc; + + if (book3e_htw_mode != PPC_HTW_NONE) { + unsigned long start = address & PMD_MASK; + unsigned long end = address + PMD_SIZE; + unsigned long size = 1UL << mmu_psize_defs[mmu_pte_psize].shift; + + /* This isn't the most optimal, ideally we would factor out the + * while preempt & CPU mask mucking around, or even the IPI but + * it will do for now + */ + while (start < end) { + __flush_tlb_page(tlb->mm, start, tsize, 1); + start += size; + } + } else { + unsigned long rmask = 0xf000000000000000ul; + unsigned long rid = (address & rmask) | 0x1000000000000000ul; + unsigned long vpte = address & ~rmask; + + vpte = (vpte >> (PAGE_SHIFT - 3)) & ~0xffful; + vpte |= rid; + __flush_tlb_page(tlb->mm, vpte, tsize, 0); + } +} + +static void __init setup_page_sizes(void) +{ + unsigned int tlb0cfg; + unsigned int tlb0ps; + unsigned int eptcfg; + int i, psize; + +#ifdef CONFIG_PPC_E500 + unsigned int mmucfg = mfspr(SPRN_MMUCFG); + int fsl_mmu = mmu_has_feature(MMU_FTR_TYPE_FSL_E); + + if (fsl_mmu && (mmucfg & MMUCFG_MAVN) == MMUCFG_MAVN_V1) { + unsigned int tlb1cfg = mfspr(SPRN_TLB1CFG); + unsigned int min_pg, max_pg; + + min_pg = (tlb1cfg & TLBnCFG_MINSIZE) >> TLBnCFG_MINSIZE_SHIFT; + max_pg = (tlb1cfg & TLBnCFG_MAXSIZE) >> TLBnCFG_MAXSIZE_SHIFT; + + for (psize = 0; psize < MMU_PAGE_COUNT; ++psize) { + struct mmu_psize_def *def; + unsigned int shift; + + def = &mmu_psize_defs[psize]; + shift = def->shift; + + if (shift == 0 || shift & 1) + continue; + + /* adjust to be in terms of 4^shift Kb */ + shift = (shift - 10) >> 1; + + if ((shift >= min_pg) && (shift <= max_pg)) + def->flags |= MMU_PAGE_SIZE_DIRECT; + } + + goto out; + } + + if (fsl_mmu && (mmucfg & MMUCFG_MAVN) == MMUCFG_MAVN_V2) { + u32 tlb1cfg, tlb1ps; + + tlb0cfg = mfspr(SPRN_TLB0CFG); + tlb1cfg = mfspr(SPRN_TLB1CFG); + tlb1ps = mfspr(SPRN_TLB1PS); + eptcfg = mfspr(SPRN_EPTCFG); + + if ((tlb1cfg & TLBnCFG_IND) && (tlb0cfg & TLBnCFG_PT)) + book3e_htw_mode = PPC_HTW_E6500; + + /* + * We expect 4K subpage size and unrestricted indirect size. + * The lack of a restriction on indirect size is a Freescale + * extension, indicated by PSn = 0 but SPSn != 0. + */ + if (eptcfg != 2) + book3e_htw_mode = PPC_HTW_NONE; + + for (psize = 0; psize < MMU_PAGE_COUNT; ++psize) { + struct mmu_psize_def *def = &mmu_psize_defs[psize]; + + if (!def->shift) + continue; + + if (tlb1ps & (1U << (def->shift - 10))) { + def->flags |= MMU_PAGE_SIZE_DIRECT; + + if (book3e_htw_mode && psize == MMU_PAGE_2M) + def->flags |= MMU_PAGE_SIZE_INDIRECT; + } + } + + goto out; + } +#endif + + tlb0cfg = mfspr(SPRN_TLB0CFG); + tlb0ps = mfspr(SPRN_TLB0PS); + eptcfg = mfspr(SPRN_EPTCFG); + + /* Look for supported direct sizes */ + for (psize = 0; psize < MMU_PAGE_COUNT; ++psize) { + struct mmu_psize_def *def = &mmu_psize_defs[psize]; + + if (tlb0ps & (1U << (def->shift - 10))) + def->flags |= MMU_PAGE_SIZE_DIRECT; + } + + /* Indirect page sizes supported ? */ + if ((tlb0cfg & TLBnCFG_IND) == 0 || + (tlb0cfg & TLBnCFG_PT) == 0) + goto out; + + book3e_htw_mode = PPC_HTW_IBM; + + /* Now, we only deal with one IND page size for each + * direct size. Hopefully all implementations today are + * unambiguous, but we might want to be careful in the + * future. + */ + for (i = 0; i < 3; i++) { + unsigned int ps, sps; + + sps = eptcfg & 0x1f; + eptcfg >>= 5; + ps = eptcfg & 0x1f; + eptcfg >>= 5; + if (!ps || !sps) + continue; + for (psize = 0; psize < MMU_PAGE_COUNT; psize++) { + struct mmu_psize_def *def = &mmu_psize_defs[psize]; + + if (ps == (def->shift - 10)) + def->flags |= MMU_PAGE_SIZE_INDIRECT; + if (sps == (def->shift - 10)) + def->ind = ps + 10; + } + } + +out: + /* Cleanup array and print summary */ + pr_info("MMU: Supported page sizes\n"); + for (psize = 0; psize < MMU_PAGE_COUNT; ++psize) { + struct mmu_psize_def *def = &mmu_psize_defs[psize]; + const char *__page_type_names[] = { + "unsupported", + "direct", + "indirect", + "direct & indirect" + }; + if (def->flags == 0) { + def->shift = 0; + continue; + } + pr_info(" %8ld KB as %s\n", 1ul << (def->shift - 10), + __page_type_names[def->flags & 0x3]); + } +} + +static void __init setup_mmu_htw(void) +{ + /* + * If we want to use HW tablewalk, enable it by patching the TLB miss + * handlers to branch to the one dedicated to it. + */ + + switch (book3e_htw_mode) { + case PPC_HTW_IBM: + patch_exception(0x1c0, exc_data_tlb_miss_htw_book3e); + patch_exception(0x1e0, exc_instruction_tlb_miss_htw_book3e); + break; +#ifdef CONFIG_PPC_E500 + case PPC_HTW_E6500: + extlb_level_exc = EX_TLB_SIZE; + patch_exception(0x1c0, exc_data_tlb_miss_e6500_book3e); + patch_exception(0x1e0, exc_instruction_tlb_miss_e6500_book3e); + break; +#endif + } + pr_info("MMU: Book3E HW tablewalk %s\n", + book3e_htw_mode != PPC_HTW_NONE ? "enabled" : "not supported"); +} + +/* + * Early initialization of the MMU TLB code + */ +static void early_init_this_mmu(void) +{ + unsigned int mas4; + + /* Set MAS4 based on page table setting */ + + mas4 = 0x4 << MAS4_WIMGED_SHIFT; + switch (book3e_htw_mode) { + case PPC_HTW_E6500: + mas4 |= MAS4_INDD; + mas4 |= BOOK3E_PAGESZ_2M << MAS4_TSIZED_SHIFT; + mas4 |= MAS4_TLBSELD(1); + mmu_pte_psize = MMU_PAGE_2M; + break; + + case PPC_HTW_IBM: + mas4 |= MAS4_INDD; + mas4 |= BOOK3E_PAGESZ_1M << MAS4_TSIZED_SHIFT; + mmu_pte_psize = MMU_PAGE_1M; + break; + + case PPC_HTW_NONE: + mas4 |= BOOK3E_PAGESZ_4K << MAS4_TSIZED_SHIFT; + mmu_pte_psize = mmu_virtual_psize; + break; + } + mtspr(SPRN_MAS4, mas4); + +#ifdef CONFIG_PPC_E500 + if (mmu_has_feature(MMU_FTR_TYPE_FSL_E)) { + unsigned int num_cams; + bool map = true; + + /* use a quarter of the TLBCAM for bolted linear map */ + num_cams = (mfspr(SPRN_TLB1CFG) & TLBnCFG_N_ENTRY) / 4; + + /* + * Only do the mapping once per core, or else the + * transient mapping would cause problems. + */ +#ifdef CONFIG_SMP + if (hweight32(get_tensr()) > 1) + map = false; +#endif + + if (map) + linear_map_top = map_mem_in_cams(linear_map_top, + num_cams, false, true); + } +#endif + + /* A sync won't hurt us after mucking around with + * the MMU configuration + */ + mb(); +} + +static void __init early_init_mmu_global(void) +{ + /* XXX This should be decided at runtime based on supported + * page sizes in the TLB, but for now let's assume 16M is + * always there and a good fit (which it probably is) + * + * Freescale booke only supports 4K pages in TLB0, so use that. + */ + if (mmu_has_feature(MMU_FTR_TYPE_FSL_E)) + mmu_vmemmap_psize = MMU_PAGE_4K; + else + mmu_vmemmap_psize = MMU_PAGE_16M; + + /* XXX This code only checks for TLB 0 capabilities and doesn't + * check what page size combos are supported by the HW. It + * also doesn't handle the case where a separate array holds + * the IND entries from the array loaded by the PT. + */ + /* Look for supported page sizes */ + setup_page_sizes(); + + /* Look for HW tablewalk support */ + setup_mmu_htw(); + +#ifdef CONFIG_PPC_E500 + if (mmu_has_feature(MMU_FTR_TYPE_FSL_E)) { + if (book3e_htw_mode == PPC_HTW_NONE) { + extlb_level_exc = EX_TLB_SIZE; + patch_exception(0x1c0, exc_data_tlb_miss_bolted_book3e); + patch_exception(0x1e0, + exc_instruction_tlb_miss_bolted_book3e); + } + } +#endif + + /* Set the global containing the top of the linear mapping + * for use by the TLB miss code + */ + linear_map_top = memblock_end_of_DRAM(); + + ioremap_bot = IOREMAP_BASE; +} + +static void __init early_mmu_set_memory_limit(void) +{ +#ifdef CONFIG_PPC_E500 + if (mmu_has_feature(MMU_FTR_TYPE_FSL_E)) { + /* + * Limit memory so we dont have linear faults. + * Unlike memblock_set_current_limit, which limits + * memory available during early boot, this permanently + * reduces the memory available to Linux. We need to + * do this because highmem is not supported on 64-bit. + */ + memblock_enforce_memory_limit(linear_map_top); + } +#endif + + memblock_set_current_limit(linear_map_top); +} + +/* boot cpu only */ +void __init early_init_mmu(void) +{ + early_init_mmu_global(); + early_init_this_mmu(); + early_mmu_set_memory_limit(); +} + +void early_init_mmu_secondary(void) +{ + early_init_this_mmu(); +} + +void setup_initial_memory_limit(phys_addr_t first_memblock_base, + phys_addr_t first_memblock_size) +{ + /* On non-FSL Embedded 64-bit, we adjust the RMA size to match + * the bolted TLB entry. We know for now that only 1G + * entries are supported though that may eventually + * change. + * + * on FSL Embedded 64-bit, usually all RAM is bolted, but with + * unusual memory sizes it's possible for some RAM to not be mapped + * (such RAM is not used at all by Linux, since we don't support + * highmem on 64-bit). We limit ppc64_rma_size to what would be + * mappable if this memblock is the only one. Additional memblocks + * can only increase, not decrease, the amount that ends up getting + * mapped. We still limit max to 1G even if we'll eventually map + * more. This is due to what the early init code is set up to do. + * + * We crop it to the size of the first MEMBLOCK to + * avoid going over total available memory just in case... + */ +#ifdef CONFIG_PPC_E500 + if (early_mmu_has_feature(MMU_FTR_TYPE_FSL_E)) { + unsigned long linear_sz; + unsigned int num_cams; + + /* use a quarter of the TLBCAM for bolted linear map */ + num_cams = (mfspr(SPRN_TLB1CFG) & TLBnCFG_N_ENTRY) / 4; + + linear_sz = map_mem_in_cams(first_memblock_size, num_cams, + true, true); + + ppc64_rma_size = min_t(u64, linear_sz, 0x40000000); + } else +#endif + ppc64_rma_size = min_t(u64, first_memblock_size, 0x40000000); + + /* Finally limit subsequent allocations */ + memblock_set_current_limit(first_memblock_base + ppc64_rma_size); +} +#else /* ! CONFIG_PPC64 */ +void __init early_init_mmu(void) +{ +#ifdef CONFIG_PPC_47x + early_init_mmu_47x(); +#endif +} +#endif /* CONFIG_PPC64 */ diff --git a/arch/powerpc/mm/nohash/tlb_low.S b/arch/powerpc/mm/nohash/tlb_low.S new file mode 100644 index 000000000..e1199608f --- /dev/null +++ b/arch/powerpc/mm/nohash/tlb_low.S @@ -0,0 +1,472 @@ +/* SPDX-License-Identifier: GPL-2.0-or-later */ +/* + * This file contains low-level functions for performing various + * types of TLB invalidations on various processors with no hash + * table. + * + * This file implements the following functions for all no-hash + * processors. Some aren't implemented for some variants. Some + * are inline in tlbflush.h + * + * - tlbil_va + * - tlbil_pid + * - tlbil_all + * - tlbivax_bcast + * + * Code mostly moved over from misc_32.S + * + * Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org) + * + * Partially rewritten by Cort Dougan (cort@cs.nmt.edu) + * Paul Mackerras, Kumar Gala and Benjamin Herrenschmidt. + */ + +#include <asm/reg.h> +#include <asm/page.h> +#include <asm/cputable.h> +#include <asm/mmu.h> +#include <asm/ppc_asm.h> +#include <asm/asm-offsets.h> +#include <asm/processor.h> +#include <asm/bug.h> +#include <asm/asm-compat.h> +#include <asm/feature-fixups.h> + +#if defined(CONFIG_40x) + +/* + * 40x implementation needs only tlbil_va + */ +_GLOBAL(__tlbil_va) + /* We run the search with interrupts disabled because we have to change + * the PID and I don't want to preempt when that happens. + */ + mfmsr r5 + mfspr r6,SPRN_PID + wrteei 0 + mtspr SPRN_PID,r4 + tlbsx. r3, 0, r3 + mtspr SPRN_PID,r6 + wrtee r5 + bne 1f + sync + /* There are only 64 TLB entries, so r3 < 64, which means bit 25 is + * clear. Since 25 is the V bit in the TLB_TAG, loading this value + * will invalidate the TLB entry. */ + tlbwe r3, r3, TLB_TAG + isync +1: blr + +#elif defined(CONFIG_PPC_8xx) + +/* + * Nothing to do for 8xx, everything is inline + */ + +#elif defined(CONFIG_44x) /* Includes 47x */ + +/* + * 440 implementation uses tlbsx/we for tlbil_va and a full sweep + * of the TLB for everything else. + */ +_GLOBAL(__tlbil_va) + mfspr r5,SPRN_MMUCR + mfmsr r10 + + /* + * We write 16 bits of STID since 47x supports that much, we + * will never be passed out of bounds values on 440 (hopefully) + */ + rlwimi r5,r4,0,16,31 + + /* We have to run the search with interrupts disabled, otherwise + * an interrupt which causes a TLB miss can clobber the MMUCR + * between the mtspr and the tlbsx. + * + * Critical and Machine Check interrupts take care of saving + * and restoring MMUCR, so only normal interrupts have to be + * taken care of. + */ + wrteei 0 + mtspr SPRN_MMUCR,r5 + tlbsx. r6,0,r3 + bne 10f + sync +#ifndef CONFIG_PPC_47x + /* On 440 There are only 64 TLB entries, so r3 < 64, which means bit + * 22, is clear. Since 22 is the V bit in the TLB_PAGEID, loading this + * value will invalidate the TLB entry. + */ + tlbwe r6,r6,PPC44x_TLB_PAGEID +#else + oris r7,r6,0x8000 /* specify way explicitly */ + clrrwi r4,r3,12 /* get an EPN for the hashing with V = 0 */ + ori r4,r4,PPC47x_TLBE_SIZE + tlbwe r4,r7,0 /* write it */ +#endif /* !CONFIG_PPC_47x */ + isync +10: wrtee r10 + blr + +_GLOBAL(_tlbil_all) +_GLOBAL(_tlbil_pid) +#ifndef CONFIG_PPC_47x + li r3,0 + sync + + /* Load high watermark */ + lis r4,tlb_44x_hwater@ha + lwz r5,tlb_44x_hwater@l(r4) + +1: tlbwe r3,r3,PPC44x_TLB_PAGEID + addi r3,r3,1 + cmpw 0,r3,r5 + ble 1b + + isync + blr +#else + /* 476 variant. There's not simple way to do this, hopefully we'll + * try to limit the amount of such full invalidates + */ + mfmsr r11 /* Interrupts off */ + wrteei 0 + li r3,-1 /* Current set */ + lis r10,tlb_47x_boltmap@h + ori r10,r10,tlb_47x_boltmap@l + lis r7,0x8000 /* Specify way explicitly */ + + b 9f /* For each set */ + +1: li r9,4 /* Number of ways */ + li r4,0 /* Current way */ + li r6,0 /* Default entry value 0 */ + andi. r0,r8,1 /* Check if way 0 is bolted */ + mtctr r9 /* Load way counter */ + bne- 3f /* Bolted, skip loading it */ + +2: /* For each way */ + or r5,r3,r4 /* Make way|index for tlbre */ + rlwimi r5,r5,16,8,15 /* Copy index into position */ + tlbre r6,r5,0 /* Read entry */ +3: addis r4,r4,0x2000 /* Next way */ + andi. r0,r6,PPC47x_TLB0_VALID /* Valid entry ? */ + beq 4f /* Nope, skip it */ + rlwimi r7,r5,0,1,2 /* Insert way number */ + rlwinm r6,r6,0,21,19 /* Clear V */ + tlbwe r6,r7,0 /* Write it */ +4: bdnz 2b /* Loop for each way */ + srwi r8,r8,1 /* Next boltmap bit */ +9: cmpwi cr1,r3,255 /* Last set done ? */ + addi r3,r3,1 /* Next set */ + beq cr1,1f /* End of loop */ + andi. r0,r3,0x1f /* Need to load a new boltmap word ? */ + bne 1b /* No, loop */ + lwz r8,0(r10) /* Load boltmap entry */ + addi r10,r10,4 /* Next word */ + b 1b /* Then loop */ +1: isync /* Sync shadows */ + wrtee r11 + blr +#endif /* !CONFIG_PPC_47x */ + +#ifdef CONFIG_PPC_47x + +/* + * _tlbivax_bcast is only on 47x. We don't bother doing a runtime + * check though, it will blow up soon enough if we mistakenly try + * to use it on a 440. + */ +_GLOBAL(_tlbivax_bcast) + mfspr r5,SPRN_MMUCR + mfmsr r10 + rlwimi r5,r4,0,16,31 + wrteei 0 + mtspr SPRN_MMUCR,r5 + isync + PPC_TLBIVAX(0, R3) + isync + mbar + tlbsync +BEGIN_FTR_SECTION + b 1f +END_FTR_SECTION_IFSET(CPU_FTR_476_DD2) + sync + wrtee r10 + blr +/* + * DD2 HW could hang if in instruction fetch happens before msync completes. + * Touch enough instruction cache lines to ensure cache hits + */ +1: mflr r9 + bcl 20,31,$+4 +2: mflr r6 + li r7,32 + PPC_ICBT(0,R6,R7) /* touch next cache line */ + add r6,r6,r7 + PPC_ICBT(0,R6,R7) /* touch next cache line */ + add r6,r6,r7 + PPC_ICBT(0,R6,R7) /* touch next cache line */ + sync + nop + nop + nop + nop + nop + nop + nop + nop + mtlr r9 + wrtee r10 + blr +#endif /* CONFIG_PPC_47x */ + +#elif defined(CONFIG_PPC_85xx) +/* + * FSL BookE implementations. + * + * Since feature sections are using _SECTION_ELSE we need + * to have the larger code path before the _SECTION_ELSE + */ + +/* + * Flush MMU TLB on the local processor + */ +_GLOBAL(_tlbil_all) +BEGIN_MMU_FTR_SECTION + li r3,(MMUCSR0_TLBFI)@l + mtspr SPRN_MMUCSR0, r3 +1: + mfspr r3,SPRN_MMUCSR0 + andi. r3,r3,MMUCSR0_TLBFI@l + bne 1b +MMU_FTR_SECTION_ELSE + PPC_TLBILX_ALL(0,R0) +ALT_MMU_FTR_SECTION_END_IFCLR(MMU_FTR_USE_TLBILX) + msync + isync + blr + +_GLOBAL(_tlbil_pid) +BEGIN_MMU_FTR_SECTION + slwi r3,r3,16 + mfmsr r10 + wrteei 0 + mfspr r4,SPRN_MAS6 /* save MAS6 */ + mtspr SPRN_MAS6,r3 + PPC_TLBILX_PID(0,R0) + mtspr SPRN_MAS6,r4 /* restore MAS6 */ + wrtee r10 +MMU_FTR_SECTION_ELSE + li r3,(MMUCSR0_TLBFI)@l + mtspr SPRN_MMUCSR0, r3 +1: + mfspr r3,SPRN_MMUCSR0 + andi. r3,r3,MMUCSR0_TLBFI@l + bne 1b +ALT_MMU_FTR_SECTION_END_IFSET(MMU_FTR_USE_TLBILX) + msync + isync + blr + +/* + * Flush MMU TLB for a particular address, but only on the local processor + * (no broadcast) + */ +_GLOBAL(__tlbil_va) + mfmsr r10 + wrteei 0 + slwi r4,r4,16 + ori r4,r4,(MAS6_ISIZE(BOOK3E_PAGESZ_4K))@l + mtspr SPRN_MAS6,r4 /* assume AS=0 for now */ +BEGIN_MMU_FTR_SECTION + tlbsx 0,r3 + mfspr r4,SPRN_MAS1 /* check valid */ + andis. r3,r4,MAS1_VALID@h + beq 1f + rlwinm r4,r4,0,1,31 + mtspr SPRN_MAS1,r4 + tlbwe +MMU_FTR_SECTION_ELSE + PPC_TLBILX_VA(0,R3) +ALT_MMU_FTR_SECTION_END_IFCLR(MMU_FTR_USE_TLBILX) + msync + isync +1: wrtee r10 + blr +#elif defined(CONFIG_PPC_BOOK3E_64) +/* + * New Book3E (>= 2.06) implementation + * + * Note: We may be able to get away without the interrupt masking stuff + * if we save/restore MAS6 on exceptions that might modify it + */ +_GLOBAL(_tlbil_pid) + slwi r4,r3,MAS6_SPID_SHIFT + mfmsr r10 + wrteei 0 + mtspr SPRN_MAS6,r4 + PPC_TLBILX_PID(0,R0) + wrtee r10 + msync + isync + blr + +_GLOBAL(_tlbil_pid_noind) + slwi r4,r3,MAS6_SPID_SHIFT + mfmsr r10 + ori r4,r4,MAS6_SIND + wrteei 0 + mtspr SPRN_MAS6,r4 + PPC_TLBILX_PID(0,R0) + wrtee r10 + msync + isync + blr + +_GLOBAL(_tlbil_all) + PPC_TLBILX_ALL(0,R0) + msync + isync + blr + +_GLOBAL(_tlbil_va) + mfmsr r10 + wrteei 0 + cmpwi cr0,r6,0 + slwi r4,r4,MAS6_SPID_SHIFT + rlwimi r4,r5,MAS6_ISIZE_SHIFT,MAS6_ISIZE_MASK + beq 1f + rlwimi r4,r6,MAS6_SIND_SHIFT,MAS6_SIND +1: mtspr SPRN_MAS6,r4 /* assume AS=0 for now */ + PPC_TLBILX_VA(0,R3) + msync + isync + wrtee r10 + blr + +_GLOBAL(_tlbivax_bcast) + mfmsr r10 + wrteei 0 + cmpwi cr0,r6,0 + slwi r4,r4,MAS6_SPID_SHIFT + rlwimi r4,r5,MAS6_ISIZE_SHIFT,MAS6_ISIZE_MASK + beq 1f + rlwimi r4,r6,MAS6_SIND_SHIFT,MAS6_SIND +1: mtspr SPRN_MAS6,r4 /* assume AS=0 for now */ + PPC_TLBIVAX(0,R3) + mbar + tlbsync + sync + wrtee r10 + blr +#else +#error Unsupported processor type ! +#endif + +#if defined(CONFIG_PPC_E500) +/* + * extern void loadcam_entry(unsigned int index) + * + * Load TLBCAM[index] entry in to the L2 CAM MMU + * Must preserve r7, r8, r9, r10, r11, r12 + */ +_GLOBAL(loadcam_entry) + mflr r5 + LOAD_REG_ADDR_PIC(r4, TLBCAM) + mtlr r5 + mulli r5,r3,TLBCAM_SIZE + add r3,r5,r4 + lwz r4,TLBCAM_MAS0(r3) + mtspr SPRN_MAS0,r4 + lwz r4,TLBCAM_MAS1(r3) + mtspr SPRN_MAS1,r4 + PPC_LL r4,TLBCAM_MAS2(r3) + mtspr SPRN_MAS2,r4 + lwz r4,TLBCAM_MAS3(r3) + mtspr SPRN_MAS3,r4 +BEGIN_MMU_FTR_SECTION + lwz r4,TLBCAM_MAS7(r3) + mtspr SPRN_MAS7,r4 +END_MMU_FTR_SECTION_IFSET(MMU_FTR_BIG_PHYS) + isync + tlbwe + isync + blr + +/* + * Load multiple TLB entries at once, using an alternate-space + * trampoline so that we don't have to care about whether the same + * TLB entry maps us before and after. + * + * r3 = first entry to write + * r4 = number of entries to write + * r5 = temporary tlb entry (0 means no switch to AS1) + */ +_GLOBAL(loadcam_multi) + mflr r8 + /* Don't switch to AS=1 if already there */ + mfmsr r11 + andi. r11,r11,MSR_IS + bne 10f + mr. r12, r5 + beq 10f + + /* + * Set up temporary TLB entry that is the same as what we're + * running from, but in AS=1. + */ + bcl 20,31,$+4 +1: mflr r6 + tlbsx 0,r8 + mfspr r6,SPRN_MAS1 + ori r6,r6,MAS1_TS + mtspr SPRN_MAS1,r6 + mfspr r6,SPRN_MAS0 + rlwimi r6,r5,MAS0_ESEL_SHIFT,MAS0_ESEL_MASK + mr r7,r5 + mtspr SPRN_MAS0,r6 + isync + tlbwe + isync + + /* Switch to AS=1 */ + mfmsr r6 + ori r6,r6,MSR_IS|MSR_DS + mtmsr r6 + isync + +10: + mr r9,r3 + add r10,r3,r4 +2: bl loadcam_entry + addi r9,r9,1 + cmpw r9,r10 + mr r3,r9 + blt 2b + + /* Don't return to AS=0 if we were in AS=1 at function start */ + andi. r11,r11,MSR_IS + bne 3f + cmpwi r12, 0 + beq 3f + + /* Return to AS=0 and clear the temporary entry */ + mfmsr r6 + rlwinm. r6,r6,0,~(MSR_IS|MSR_DS) + mtmsr r6 + isync + + li r6,0 + mtspr SPRN_MAS1,r6 + rlwinm r6,r7,MAS0_ESEL_SHIFT,MAS0_ESEL_MASK + oris r6,r6,MAS0_TLBSEL(1)@h + mtspr SPRN_MAS0,r6 + isync + tlbwe + isync + +3: + mtlr r8 + blr +#endif diff --git a/arch/powerpc/mm/nohash/tlb_low_64e.S b/arch/powerpc/mm/nohash/tlb_low_64e.S new file mode 100644 index 000000000..76cf456d7 --- /dev/null +++ b/arch/powerpc/mm/nohash/tlb_low_64e.S @@ -0,0 +1,1169 @@ +/* SPDX-License-Identifier: GPL-2.0-or-later */ +/* + * Low level TLB miss handlers for Book3E + * + * Copyright (C) 2008-2009 + * Ben. Herrenschmidt (benh@kernel.crashing.org), IBM Corp. + */ + +#include <linux/pgtable.h> +#include <asm/processor.h> +#include <asm/reg.h> +#include <asm/page.h> +#include <asm/mmu.h> +#include <asm/ppc_asm.h> +#include <asm/asm-offsets.h> +#include <asm/cputable.h> +#include <asm/exception-64e.h> +#include <asm/ppc-opcode.h> +#include <asm/kvm_asm.h> +#include <asm/kvm_booke_hv_asm.h> +#include <asm/feature-fixups.h> + +#define VPTE_PMD_SHIFT (PTE_INDEX_SIZE) +#define VPTE_PUD_SHIFT (VPTE_PMD_SHIFT + PMD_INDEX_SIZE) +#define VPTE_PGD_SHIFT (VPTE_PUD_SHIFT + PUD_INDEX_SIZE) +#define VPTE_INDEX_SIZE (VPTE_PGD_SHIFT + PGD_INDEX_SIZE) + +/********************************************************************** + * * + * TLB miss handling for Book3E with a bolted linear mapping * + * No virtual page table, no nested TLB misses * + * * + **********************************************************************/ + +/* + * Note that, unlike non-bolted handlers, TLB_EXFRAME is not + * modified by the TLB miss handlers themselves, since the TLB miss + * handler code will not itself cause a recursive TLB miss. + * + * TLB_EXFRAME will be modified when crit/mc/debug exceptions are + * entered/exited. + */ +.macro tlb_prolog_bolted intnum addr + mtspr SPRN_SPRG_GEN_SCRATCH,r12 + mfspr r12,SPRN_SPRG_TLB_EXFRAME + std r13,EX_TLB_R13(r12) + std r10,EX_TLB_R10(r12) + mfspr r13,SPRN_SPRG_PACA + + mfcr r10 + std r11,EX_TLB_R11(r12) +#ifdef CONFIG_KVM_BOOKE_HV +BEGIN_FTR_SECTION + mfspr r11, SPRN_SRR1 +END_FTR_SECTION_IFSET(CPU_FTR_EMB_HV) +#endif + DO_KVM \intnum, SPRN_SRR1 + std r16,EX_TLB_R16(r12) + mfspr r16,\addr /* get faulting address */ + std r14,EX_TLB_R14(r12) + ld r14,PACAPGD(r13) + std r15,EX_TLB_R15(r12) + std r10,EX_TLB_CR(r12) +START_BTB_FLUSH_SECTION + mfspr r11, SPRN_SRR1 + andi. r10,r11,MSR_PR + beq 1f + BTB_FLUSH(r10) +1: +END_BTB_FLUSH_SECTION + std r7,EX_TLB_R7(r12) +.endm + +.macro tlb_epilog_bolted + ld r14,EX_TLB_CR(r12) + ld r7,EX_TLB_R7(r12) + ld r10,EX_TLB_R10(r12) + ld r11,EX_TLB_R11(r12) + ld r13,EX_TLB_R13(r12) + mtcr r14 + ld r14,EX_TLB_R14(r12) + ld r15,EX_TLB_R15(r12) + ld r16,EX_TLB_R16(r12) + mfspr r12,SPRN_SPRG_GEN_SCRATCH +.endm + +/* Data TLB miss */ + START_EXCEPTION(data_tlb_miss_bolted) + tlb_prolog_bolted BOOKE_INTERRUPT_DTLB_MISS SPRN_DEAR + + /* We need _PAGE_PRESENT and _PAGE_ACCESSED set */ + + /* We do the user/kernel test for the PID here along with the RW test + */ + /* We pre-test some combination of permissions to avoid double + * faults: + * + * We move the ESR:ST bit into the position of _PAGE_BAP_SW in the PTE + * ESR_ST is 0x00800000 + * _PAGE_BAP_SW is 0x00000010 + * So the shift is >> 19. This tests for supervisor writeability. + * If the page happens to be supervisor writeable and not user + * writeable, we will take a new fault later, but that should be + * a rare enough case. + * + * We also move ESR_ST in _PAGE_DIRTY position + * _PAGE_DIRTY is 0x00001000 so the shift is >> 11 + * + * MAS1 is preset for all we need except for TID that needs to + * be cleared for kernel translations + */ + + mfspr r11,SPRN_ESR + + srdi r15,r16,60 /* get region */ + rldicl. r10,r16,64-PGTABLE_EADDR_SIZE,PGTABLE_EADDR_SIZE+4 + bne- dtlb_miss_fault_bolted /* Bail if fault addr is invalid */ + + rlwinm r10,r11,32-19,27,27 + rlwimi r10,r11,32-16,19,19 + cmpwi r15,0 /* user vs kernel check */ + ori r10,r10,_PAGE_PRESENT + oris r11,r10,_PAGE_ACCESSED@h + + bne tlb_miss_kernel_bolted + +tlb_miss_user_bolted: +#ifdef CONFIG_PPC_KUAP + mfspr r10,SPRN_MAS1 + rlwinm. r10,r10,0,0x3fff0000 + beq- tlb_miss_fault_bolted /* KUAP fault */ +#endif + +tlb_miss_common_bolted: +/* + * This is the guts of the TLB miss handler for bolted-linear. + * We are entered with: + * + * r16 = faulting address + * r15 = crap (free to use) + * r14 = page table base + * r13 = PACA + * r11 = PTE permission mask + * r10 = crap (free to use) + */ + rldicl r15,r16,64-PGDIR_SHIFT+3,64-PGD_INDEX_SIZE-3 + cmpldi cr0,r14,0 + clrrdi r15,r15,3 + beq tlb_miss_fault_bolted /* No PGDIR, bail */ + + ldx r14,r14,r15 /* grab pgd entry */ + + rldicl r15,r16,64-PUD_SHIFT+3,64-PUD_INDEX_SIZE-3 + clrrdi r15,r15,3 + cmpdi cr0,r14,0 + bge tlb_miss_fault_bolted /* Bad pgd entry or hugepage; bail */ + ldx r14,r14,r15 /* grab pud entry */ + + rldicl r15,r16,64-PMD_SHIFT+3,64-PMD_INDEX_SIZE-3 + clrrdi r15,r15,3 + cmpdi cr0,r14,0 + bge tlb_miss_fault_bolted + ldx r14,r14,r15 /* Grab pmd entry */ + + rldicl r15,r16,64-PAGE_SHIFT+3,64-PTE_INDEX_SIZE-3 + clrrdi r15,r15,3 + cmpdi cr0,r14,0 + bge tlb_miss_fault_bolted + ldx r14,r14,r15 /* Grab PTE, normal (!huge) page */ + + /* Check if required permissions are met */ + andc. r15,r11,r14 + rldicr r15,r14,64-(PTE_RPN_SHIFT-PAGE_SHIFT),63-PAGE_SHIFT + bne- tlb_miss_fault_bolted + + /* Now we build the MAS: + * + * MAS 0 : Fully setup with defaults in MAS4 and TLBnCFG + * MAS 1 : Almost fully setup + * - PID already updated by caller if necessary + * - TSIZE need change if !base page size, not + * yet implemented for now + * MAS 2 : Defaults not useful, need to be redone + * MAS 3+7 : Needs to be done + */ + clrrdi r11,r16,12 /* Clear low crap in EA */ + clrldi r15,r15,12 /* Clear crap at the top */ + rlwimi r11,r14,32-19,27,31 /* Insert WIMGE */ + rlwimi r15,r14,32-8,22,25 /* Move in U bits */ + mtspr SPRN_MAS2,r11 + andi. r11,r14,_PAGE_DIRTY + rlwimi r15,r14,32-2,26,31 /* Move in BAP bits */ + + /* Mask out SW and UW if !DIRTY (XXX optimize this !) */ + bne 1f + li r11,MAS3_SW|MAS3_UW + andc r15,r15,r11 +1: + mtspr SPRN_MAS7_MAS3,r15 + tlbwe + +tlb_miss_done_bolted: + tlb_epilog_bolted + rfi + +itlb_miss_kernel_bolted: + li r11,_PAGE_PRESENT|_PAGE_BAP_SX /* Base perm */ + oris r11,r11,_PAGE_ACCESSED@h +tlb_miss_kernel_bolted: + mfspr r10,SPRN_MAS1 + ld r14,PACA_KERNELPGD(r13) + srdi r15,r16,44 /* get kernel region */ + andi. r15,r15,1 /* Check for vmalloc region */ + rlwinm r10,r10,0,16,1 /* Clear TID */ + mtspr SPRN_MAS1,r10 + bne+ tlb_miss_common_bolted + +tlb_miss_fault_bolted: + /* We need to check if it was an instruction miss */ + andi. r10,r11,_PAGE_BAP_UX|_PAGE_BAP_SX + bne itlb_miss_fault_bolted +dtlb_miss_fault_bolted: + tlb_epilog_bolted + b exc_data_storage_book3e +itlb_miss_fault_bolted: + tlb_epilog_bolted + b exc_instruction_storage_book3e + +/* Instruction TLB miss */ + START_EXCEPTION(instruction_tlb_miss_bolted) + tlb_prolog_bolted BOOKE_INTERRUPT_ITLB_MISS SPRN_SRR0 + + rldicl. r10,r16,64-PGTABLE_EADDR_SIZE,PGTABLE_EADDR_SIZE+4 + srdi r15,r16,60 /* get region */ + bne- itlb_miss_fault_bolted + + li r11,_PAGE_PRESENT|_PAGE_BAP_UX /* Base perm */ + + /* We do the user/kernel test for the PID here along with the RW test + */ + + cmpldi cr0,r15,0 /* Check for user region */ + oris r11,r11,_PAGE_ACCESSED@h + beq tlb_miss_user_bolted + b itlb_miss_kernel_bolted + +/* + * TLB miss handling for e6500 and derivatives, using hardware tablewalk. + * + * Linear mapping is bolted: no virtual page table or nested TLB misses + * Indirect entries in TLB1, hardware loads resulting direct entries + * into TLB0 + * No HES or NV hint on TLB1, so we need to do software round-robin + * No tlbsrx. so we need a spinlock, and we have to deal + * with MAS-damage caused by tlbsx + * 4K pages only + */ + + START_EXCEPTION(instruction_tlb_miss_e6500) + tlb_prolog_bolted BOOKE_INTERRUPT_ITLB_MISS SPRN_SRR0 + + ld r11,PACA_TCD_PTR(r13) + srdi. r15,r16,60 /* get region */ + ori r16,r16,1 + + bne tlb_miss_kernel_e6500 /* user/kernel test */ + + b tlb_miss_common_e6500 + + START_EXCEPTION(data_tlb_miss_e6500) + tlb_prolog_bolted BOOKE_INTERRUPT_DTLB_MISS SPRN_DEAR + + ld r11,PACA_TCD_PTR(r13) + srdi. r15,r16,60 /* get region */ + rldicr r16,r16,0,62 + + bne tlb_miss_kernel_e6500 /* user vs kernel check */ + +/* + * This is the guts of the TLB miss handler for e6500 and derivatives. + * We are entered with: + * + * r16 = page of faulting address (low bit 0 if data, 1 if instruction) + * r15 = crap (free to use) + * r14 = page table base + * r13 = PACA + * r11 = tlb_per_core ptr + * r10 = crap (free to use) + * r7 = esel_next + */ +tlb_miss_common_e6500: + crmove cr2*4+2,cr0*4+2 /* cr2.eq != 0 if kernel address */ + +BEGIN_FTR_SECTION /* CPU_FTR_SMT */ + /* + * Search if we already have an indirect entry for that virtual + * address, and if we do, bail out. + * + * MAS6:IND should be already set based on MAS4 + */ + lhz r10,PACAPACAINDEX(r13) + addi r10,r10,1 + crclr cr1*4+eq /* set cr1.eq = 0 for non-recursive */ +1: lbarx r15,0,r11 + cmpdi r15,0 + bne 2f + stbcx. r10,0,r11 + bne 1b +3: + .subsection 1 +2: cmpd cr1,r15,r10 /* recursive lock due to mcheck/crit/etc? */ + beq cr1,3b /* unlock will happen if cr1.eq = 0 */ +10: lbz r15,0(r11) + cmpdi r15,0 + bne 10b + b 1b + .previous +END_FTR_SECTION_IFSET(CPU_FTR_SMT) + + lbz r7,TCD_ESEL_NEXT(r11) + +BEGIN_FTR_SECTION /* CPU_FTR_SMT */ + /* + * Erratum A-008139 says that we can't use tlbwe to change + * an indirect entry in any way (including replacing or + * invalidating) if the other thread could be in the process + * of a lookup. The workaround is to invalidate the entry + * with tlbilx before overwriting. + */ + + rlwinm r10,r7,16,0xff0000 + oris r10,r10,MAS0_TLBSEL(1)@h + mtspr SPRN_MAS0,r10 + isync + tlbre + mfspr r15,SPRN_MAS1 + andis. r15,r15,MAS1_VALID@h + beq 5f + +BEGIN_FTR_SECTION_NESTED(532) + mfspr r10,SPRN_MAS8 + rlwinm r10,r10,0,0x80000fff /* tgs,tlpid -> sgs,slpid */ + mtspr SPRN_MAS5,r10 +END_FTR_SECTION_NESTED(CPU_FTR_EMB_HV,CPU_FTR_EMB_HV,532) + + mfspr r10,SPRN_MAS1 + rlwinm r15,r10,0,0x3fff0000 /* tid -> spid */ + rlwimi r15,r10,20,0x00000003 /* ind,ts -> sind,sas */ + mfspr r10,SPRN_MAS6 + mtspr SPRN_MAS6,r15 + + mfspr r15,SPRN_MAS2 + isync + tlbilxva 0,r15 + isync + + mtspr SPRN_MAS6,r10 + +5: +BEGIN_FTR_SECTION_NESTED(532) + li r10,0 + mtspr SPRN_MAS8,r10 + mtspr SPRN_MAS5,r10 +END_FTR_SECTION_NESTED(CPU_FTR_EMB_HV,CPU_FTR_EMB_HV,532) + + tlbsx 0,r16 + mfspr r10,SPRN_MAS1 + andis. r15,r10,MAS1_VALID@h + bne tlb_miss_done_e6500 +FTR_SECTION_ELSE + mfspr r10,SPRN_MAS1 +ALT_FTR_SECTION_END_IFSET(CPU_FTR_SMT) + + oris r10,r10,MAS1_VALID@h + beq cr2,4f + rlwinm r10,r10,0,16,1 /* Clear TID */ +4: mtspr SPRN_MAS1,r10 + + /* Now, we need to walk the page tables. First check if we are in + * range. + */ + rldicl. r10,r16,64-PGTABLE_EADDR_SIZE,PGTABLE_EADDR_SIZE+4 + bne- tlb_miss_fault_e6500 + + rldicl r15,r16,64-PGDIR_SHIFT+3,64-PGD_INDEX_SIZE-3 + cmpldi cr0,r14,0 + clrrdi r15,r15,3 + beq- tlb_miss_fault_e6500 /* No PGDIR, bail */ + ldx r14,r14,r15 /* grab pgd entry */ + + rldicl r15,r16,64-PUD_SHIFT+3,64-PUD_INDEX_SIZE-3 + clrrdi r15,r15,3 + cmpdi cr0,r14,0 + bge tlb_miss_huge_e6500 /* Bad pgd entry or hugepage; bail */ + ldx r14,r14,r15 /* grab pud entry */ + + rldicl r15,r16,64-PMD_SHIFT+3,64-PMD_INDEX_SIZE-3 + clrrdi r15,r15,3 + cmpdi cr0,r14,0 + bge tlb_miss_huge_e6500 + ldx r14,r14,r15 /* Grab pmd entry */ + + mfspr r10,SPRN_MAS0 + cmpdi cr0,r14,0 + bge tlb_miss_huge_e6500 + + /* Now we build the MAS for a 2M indirect page: + * + * MAS 0 : ESEL needs to be filled by software round-robin + * MAS 1 : Fully set up + * - PID already updated by caller if necessary + * - TSIZE for now is base ind page size always + * - TID already cleared if necessary + * MAS 2 : Default not 2M-aligned, need to be redone + * MAS 3+7 : Needs to be done + */ + + ori r14,r14,(BOOK3E_PAGESZ_4K << MAS3_SPSIZE_SHIFT) + mtspr SPRN_MAS7_MAS3,r14 + + clrrdi r15,r16,21 /* make EA 2M-aligned */ + mtspr SPRN_MAS2,r15 + +tlb_miss_huge_done_e6500: + lbz r16,TCD_ESEL_MAX(r11) + lbz r14,TCD_ESEL_FIRST(r11) + rlwimi r10,r7,16,0x00ff0000 /* insert esel_next into MAS0 */ + addi r7,r7,1 /* increment esel_next */ + mtspr SPRN_MAS0,r10 + cmpw r7,r16 + iseleq r7,r14,r7 /* if next == last use first */ + stb r7,TCD_ESEL_NEXT(r11) + + tlbwe + +tlb_miss_done_e6500: + .macro tlb_unlock_e6500 +BEGIN_FTR_SECTION + beq cr1,1f /* no unlock if lock was recursively grabbed */ + li r15,0 + isync + stb r15,0(r11) +1: +END_FTR_SECTION_IFSET(CPU_FTR_SMT) + .endm + + tlb_unlock_e6500 + tlb_epilog_bolted + rfi + +tlb_miss_huge_e6500: + beq tlb_miss_fault_e6500 + li r10,1 + andi. r15,r14,HUGEPD_SHIFT_MASK@l /* r15 = psize */ + rldimi r14,r10,63,0 /* Set PD_HUGE */ + xor r14,r14,r15 /* Clear size bits */ + ldx r14,0,r14 + + /* + * Now we build the MAS for a huge page. + * + * MAS 0 : ESEL needs to be filled by software round-robin + * - can be handled by indirect code + * MAS 1 : Need to clear IND and set TSIZE + * MAS 2,3+7: Needs to be redone similar to non-tablewalk handler + */ + + subi r15,r15,10 /* Convert psize to tsize */ + mfspr r10,SPRN_MAS1 + rlwinm r10,r10,0,~MAS1_IND + rlwimi r10,r15,MAS1_TSIZE_SHIFT,MAS1_TSIZE_MASK + mtspr SPRN_MAS1,r10 + + li r10,-0x400 + sld r15,r10,r15 /* Generate mask based on size */ + and r10,r16,r15 + rldicr r15,r14,64-(PTE_RPN_SHIFT-PAGE_SHIFT),63-PAGE_SHIFT + rlwimi r10,r14,32-19,27,31 /* Insert WIMGE */ + clrldi r15,r15,PAGE_SHIFT /* Clear crap at the top */ + rlwimi r15,r14,32-8,22,25 /* Move in U bits */ + mtspr SPRN_MAS2,r10 + andi. r10,r14,_PAGE_DIRTY + rlwimi r15,r14,32-2,26,31 /* Move in BAP bits */ + + /* Mask out SW and UW if !DIRTY (XXX optimize this !) */ + bne 1f + li r10,MAS3_SW|MAS3_UW + andc r15,r15,r10 +1: + mtspr SPRN_MAS7_MAS3,r15 + + mfspr r10,SPRN_MAS0 + b tlb_miss_huge_done_e6500 + +tlb_miss_kernel_e6500: + ld r14,PACA_KERNELPGD(r13) + srdi r15,r16,44 /* get kernel region */ + xoris r15,r15,0xc /* Check for vmalloc region */ + cmplwi cr1,r15,1 + beq+ cr1,tlb_miss_common_e6500 + +tlb_miss_fault_e6500: + tlb_unlock_e6500 + /* We need to check if it was an instruction miss */ + andi. r16,r16,1 + bne itlb_miss_fault_e6500 +dtlb_miss_fault_e6500: + tlb_epilog_bolted + b exc_data_storage_book3e +itlb_miss_fault_e6500: + tlb_epilog_bolted + b exc_instruction_storage_book3e + +/********************************************************************** + * * + * TLB miss handling for Book3E with TLB reservation and HES support * + * * + **********************************************************************/ + + +/* Data TLB miss */ + START_EXCEPTION(data_tlb_miss) + TLB_MISS_PROLOG + + /* Now we handle the fault proper. We only save DEAR in normal + * fault case since that's the only interesting values here. + * We could probably also optimize by not saving SRR0/1 in the + * linear mapping case but I'll leave that for later + */ + mfspr r14,SPRN_ESR + mfspr r16,SPRN_DEAR /* get faulting address */ + srdi r15,r16,44 /* get region */ + xoris r15,r15,0xc + cmpldi cr0,r15,0 /* linear mapping ? */ + beq tlb_load_linear /* yes -> go to linear map load */ + cmpldi cr1,r15,1 /* vmalloc mapping ? */ + + /* The page tables are mapped virtually linear. At this point, though, + * we don't know whether we are trying to fault in a first level + * virtual address or a virtual page table address. We can get that + * from bit 0x1 of the region ID which we have set for a page table + */ + andis. r10,r15,0x1 + bne- virt_page_table_tlb_miss + + std r14,EX_TLB_ESR(r12); /* save ESR */ + std r16,EX_TLB_DEAR(r12); /* save DEAR */ + + /* We need _PAGE_PRESENT and _PAGE_ACCESSED set */ + li r11,_PAGE_PRESENT + oris r11,r11,_PAGE_ACCESSED@h + + /* We do the user/kernel test for the PID here along with the RW test + */ + srdi. r15,r16,60 /* Check for user region */ + + /* We pre-test some combination of permissions to avoid double + * faults: + * + * We move the ESR:ST bit into the position of _PAGE_BAP_SW in the PTE + * ESR_ST is 0x00800000 + * _PAGE_BAP_SW is 0x00000010 + * So the shift is >> 19. This tests for supervisor writeability. + * If the page happens to be supervisor writeable and not user + * writeable, we will take a new fault later, but that should be + * a rare enough case. + * + * We also move ESR_ST in _PAGE_DIRTY position + * _PAGE_DIRTY is 0x00001000 so the shift is >> 11 + * + * MAS1 is preset for all we need except for TID that needs to + * be cleared for kernel translations + */ + rlwimi r11,r14,32-19,27,27 + rlwimi r11,r14,32-16,19,19 + beq normal_tlb_miss_user + /* XXX replace the RMW cycles with immediate loads + writes */ +1: mfspr r10,SPRN_MAS1 + rlwinm r10,r10,0,16,1 /* Clear TID */ + mtspr SPRN_MAS1,r10 + beq+ cr1,normal_tlb_miss + + /* We got a crappy address, just fault with whatever DEAR and ESR + * are here + */ + TLB_MISS_EPILOG_ERROR + b exc_data_storage_book3e + +/* Instruction TLB miss */ + START_EXCEPTION(instruction_tlb_miss) + TLB_MISS_PROLOG + + /* If we take a recursive fault, the second level handler may need + * to know whether we are handling a data or instruction fault in + * order to get to the right store fault handler. We provide that + * info by writing a crazy value in ESR in our exception frame + */ + li r14,-1 /* store to exception frame is done later */ + + /* Now we handle the fault proper. We only save DEAR in the non + * linear mapping case since we know the linear mapping case will + * not re-enter. We could indeed optimize and also not save SRR0/1 + * in the linear mapping case but I'll leave that for later + * + * Faulting address is SRR0 which is already in r16 + */ + srdi r15,r16,44 /* get region */ + xoris r15,r15,0xc + cmpldi cr0,r15,0 /* linear mapping ? */ + beq tlb_load_linear /* yes -> go to linear map load */ + cmpldi cr1,r15,1 /* vmalloc mapping ? */ + + /* We do the user/kernel test for the PID here along with the RW test + */ + li r11,_PAGE_PRESENT|_PAGE_BAP_UX /* Base perm */ + oris r11,r11,_PAGE_ACCESSED@h + + srdi. r15,r16,60 /* Check for user region */ + std r14,EX_TLB_ESR(r12) /* write crazy -1 to frame */ + beq normal_tlb_miss_user + + li r11,_PAGE_PRESENT|_PAGE_BAP_SX /* Base perm */ + oris r11,r11,_PAGE_ACCESSED@h + /* XXX replace the RMW cycles with immediate loads + writes */ + mfspr r10,SPRN_MAS1 + rlwinm r10,r10,0,16,1 /* Clear TID */ + mtspr SPRN_MAS1,r10 + beq+ cr1,normal_tlb_miss + + /* We got a crappy address, just fault */ + TLB_MISS_EPILOG_ERROR + b exc_instruction_storage_book3e + +/* + * This is the guts of the first-level TLB miss handler for direct + * misses. We are entered with: + * + * r16 = faulting address + * r15 = region ID + * r14 = crap (free to use) + * r13 = PACA + * r12 = TLB exception frame in PACA + * r11 = PTE permission mask + * r10 = crap (free to use) + */ +normal_tlb_miss_user: +#ifdef CONFIG_PPC_KUAP + mfspr r14,SPRN_MAS1 + rlwinm. r14,r14,0,0x3fff0000 + beq- normal_tlb_miss_access_fault /* KUAP fault */ +#endif +normal_tlb_miss: + /* So we first construct the page table address. We do that by + * shifting the bottom of the address (not the region ID) by + * PAGE_SHIFT-3, clearing the bottom 3 bits (get a PTE ptr) and + * or'ing the fourth high bit. + * + * NOTE: For 64K pages, we do things slightly differently in + * order to handle the weird page table format used by linux + */ + srdi r15,r16,44 + oris r10,r15,0x1 + rldicl r14,r16,64-(PAGE_SHIFT-3),PAGE_SHIFT-3+4 + sldi r15,r10,44 + clrrdi r14,r14,19 + or r10,r15,r14 + + ld r14,0(r10) + +finish_normal_tlb_miss: + /* Check if required permissions are met */ + andc. r15,r11,r14 + bne- normal_tlb_miss_access_fault + + /* Now we build the MAS: + * + * MAS 0 : Fully setup with defaults in MAS4 and TLBnCFG + * MAS 1 : Almost fully setup + * - PID already updated by caller if necessary + * - TSIZE need change if !base page size, not + * yet implemented for now + * MAS 2 : Defaults not useful, need to be redone + * MAS 3+7 : Needs to be done + * + * TODO: mix up code below for better scheduling + */ + clrrdi r10,r16,12 /* Clear low crap in EA */ + rlwimi r10,r14,32-19,27,31 /* Insert WIMGE */ + mtspr SPRN_MAS2,r10 + + /* Check page size, if not standard, update MAS1 */ + rldicl r10,r14,64-8,64-8 + cmpldi cr0,r10,BOOK3E_PAGESZ_4K + beq- 1f + mfspr r11,SPRN_MAS1 + rlwimi r11,r14,31,21,24 + rlwinm r11,r11,0,21,19 + mtspr SPRN_MAS1,r11 +1: + /* Move RPN in position */ + rldicr r11,r14,64-(PTE_RPN_SHIFT-PAGE_SHIFT),63-PAGE_SHIFT + clrldi r15,r11,12 /* Clear crap at the top */ + rlwimi r15,r14,32-8,22,25 /* Move in U bits */ + rlwimi r15,r14,32-2,26,31 /* Move in BAP bits */ + + /* Mask out SW and UW if !DIRTY (XXX optimize this !) */ + andi. r11,r14,_PAGE_DIRTY + bne 1f + li r11,MAS3_SW|MAS3_UW + andc r15,r15,r11 +1: + srdi r16,r15,32 + mtspr SPRN_MAS3,r15 + mtspr SPRN_MAS7,r16 + + tlbwe + +normal_tlb_miss_done: + /* We don't bother with restoring DEAR or ESR since we know we are + * level 0 and just going back to userland. They are only needed + * if you are going to take an access fault + */ + TLB_MISS_EPILOG_SUCCESS + rfi + +normal_tlb_miss_access_fault: + /* We need to check if it was an instruction miss */ + andi. r10,r11,_PAGE_BAP_UX + bne 1f + ld r14,EX_TLB_DEAR(r12) + ld r15,EX_TLB_ESR(r12) + mtspr SPRN_DEAR,r14 + mtspr SPRN_ESR,r15 + TLB_MISS_EPILOG_ERROR + b exc_data_storage_book3e +1: TLB_MISS_EPILOG_ERROR + b exc_instruction_storage_book3e + + +/* + * This is the guts of the second-level TLB miss handler for direct + * misses. We are entered with: + * + * r16 = virtual page table faulting address + * r15 = region (top 4 bits of address) + * r14 = crap (free to use) + * r13 = PACA + * r12 = TLB exception frame in PACA + * r11 = crap (free to use) + * r10 = crap (free to use) + * + * Note that this should only ever be called as a second level handler + * with the current scheme when using SW load. + * That means we can always get the original fault DEAR at + * EX_TLB_DEAR-EX_TLB_SIZE(r12) + * + * It can be re-entered by the linear mapping miss handler. However, to + * avoid too much complication, it will restart the whole fault at level + * 0 so we don't care too much about clobbers + * + * XXX That code was written back when we couldn't clobber r14. We can now, + * so we could probably optimize things a bit + */ +virt_page_table_tlb_miss: + /* Are we hitting a kernel page table ? */ + srdi r15,r16,60 + andi. r10,r15,0x8 + + /* The cool thing now is that r10 contains 0 for user and 8 for kernel, + * and we happen to have the swapper_pg_dir at offset 8 from the user + * pgdir in the PACA :-). + */ + add r11,r10,r13 + + /* If kernel, we need to clear MAS1 TID */ + beq 1f + /* XXX replace the RMW cycles with immediate loads + writes */ + mfspr r10,SPRN_MAS1 + rlwinm r10,r10,0,16,1 /* Clear TID */ + mtspr SPRN_MAS1,r10 +#ifdef CONFIG_PPC_KUAP + b 2f +1: + mfspr r10,SPRN_MAS1 + rlwinm. r10,r10,0,0x3fff0000 + beq- virt_page_table_tlb_miss_fault /* KUAP fault */ +2: +#else +1: +#endif + + /* Now, we need to walk the page tables. First check if we are in + * range. + */ + rldicl r10,r16,64-(VPTE_INDEX_SIZE+3),VPTE_INDEX_SIZE+3+4 + cmpldi r10,0x80 + bne- virt_page_table_tlb_miss_fault + + /* Get the PGD pointer */ + ld r15,PACAPGD(r11) + cmpldi cr0,r15,0 + beq- virt_page_table_tlb_miss_fault + + /* Get to PGD entry */ + rldicl r11,r16,64-VPTE_PGD_SHIFT,64-PGD_INDEX_SIZE-3 + clrrdi r10,r11,3 + ldx r15,r10,r15 + cmpdi cr0,r15,0 + bge virt_page_table_tlb_miss_fault + + /* Get to PUD entry */ + rldicl r11,r16,64-VPTE_PUD_SHIFT,64-PUD_INDEX_SIZE-3 + clrrdi r10,r11,3 + ldx r15,r10,r15 + cmpdi cr0,r15,0 + bge virt_page_table_tlb_miss_fault + + /* Get to PMD entry */ + rldicl r11,r16,64-VPTE_PMD_SHIFT,64-PMD_INDEX_SIZE-3 + clrrdi r10,r11,3 + ldx r15,r10,r15 + cmpdi cr0,r15,0 + bge virt_page_table_tlb_miss_fault + + /* Ok, we're all right, we can now create a kernel translation for + * a 4K or 64K page from r16 -> r15. + */ + /* Now we build the MAS: + * + * MAS 0 : Fully setup with defaults in MAS4 and TLBnCFG + * MAS 1 : Almost fully setup + * - PID already updated by caller if necessary + * - TSIZE for now is base page size always + * MAS 2 : Use defaults + * MAS 3+7 : Needs to be done + * + * So we only do MAS 2 and 3 for now... + */ + clrldi r11,r15,4 /* remove region ID from RPN */ + ori r10,r11,1 /* Or-in SR */ + + srdi r16,r10,32 + mtspr SPRN_MAS3,r10 + mtspr SPRN_MAS7,r16 + + tlbwe + + /* Return to caller, normal case */ + TLB_MISS_EPILOG_SUCCESS + rfi + +virt_page_table_tlb_miss_fault: + /* If we fault here, things are a little bit tricky. We need to call + * either data or instruction store fault, and we need to retrieve + * the original fault address and ESR (for data). + * + * The thing is, we know that in normal circumstances, this is + * always called as a second level tlb miss for SW load or as a first + * level TLB miss for HW load, so we should be able to peek at the + * relevant information in the first exception frame in the PACA. + * + * However, we do need to double check that, because we may just hit + * a stray kernel pointer or a userland attack trying to hit those + * areas. If that is the case, we do a data fault. (We can't get here + * from an instruction tlb miss anyway). + * + * Note also that when going to a fault, we must unwind the previous + * level as well. Since we are doing that, we don't need to clear or + * restore the TLB reservation neither. + */ + subf r10,r13,r12 + cmpldi cr0,r10,PACA_EXTLB+EX_TLB_SIZE + bne- virt_page_table_tlb_miss_whacko_fault + + /* We dig the original DEAR and ESR from slot 0 */ + ld r15,EX_TLB_DEAR+PACA_EXTLB(r13) + ld r16,EX_TLB_ESR+PACA_EXTLB(r13) + + /* We check for the "special" ESR value for instruction faults */ + cmpdi cr0,r16,-1 + beq 1f + mtspr SPRN_DEAR,r15 + mtspr SPRN_ESR,r16 + TLB_MISS_EPILOG_ERROR + b exc_data_storage_book3e +1: TLB_MISS_EPILOG_ERROR + b exc_instruction_storage_book3e + +virt_page_table_tlb_miss_whacko_fault: + /* The linear fault will restart everything so ESR and DEAR will + * not have been clobbered, let's just fault with what we have + */ + TLB_MISS_EPILOG_ERROR + b exc_data_storage_book3e + + +/************************************************************** + * * + * TLB miss handling for Book3E with hw page table support * + * * + **************************************************************/ + + +/* Data TLB miss */ + START_EXCEPTION(data_tlb_miss_htw) + TLB_MISS_PROLOG + + /* Now we handle the fault proper. We only save DEAR in normal + * fault case since that's the only interesting values here. + * We could probably also optimize by not saving SRR0/1 in the + * linear mapping case but I'll leave that for later + */ + mfspr r14,SPRN_ESR + mfspr r16,SPRN_DEAR /* get faulting address */ + srdi r11,r16,44 /* get region */ + xoris r11,r11,0xc + cmpldi cr0,r11,0 /* linear mapping ? */ + beq tlb_load_linear /* yes -> go to linear map load */ + cmpldi cr1,r11,1 /* vmalloc mapping ? */ + + /* We do the user/kernel test for the PID here along with the RW test + */ + srdi. r11,r16,60 /* Check for user region */ + ld r15,PACAPGD(r13) /* Load user pgdir */ + beq htw_tlb_miss + + /* XXX replace the RMW cycles with immediate loads + writes */ +1: mfspr r10,SPRN_MAS1 + rlwinm r10,r10,0,16,1 /* Clear TID */ + mtspr SPRN_MAS1,r10 + ld r15,PACA_KERNELPGD(r13) /* Load kernel pgdir */ + beq+ cr1,htw_tlb_miss + + /* We got a crappy address, just fault with whatever DEAR and ESR + * are here + */ + TLB_MISS_EPILOG_ERROR + b exc_data_storage_book3e + +/* Instruction TLB miss */ + START_EXCEPTION(instruction_tlb_miss_htw) + TLB_MISS_PROLOG + + /* If we take a recursive fault, the second level handler may need + * to know whether we are handling a data or instruction fault in + * order to get to the right store fault handler. We provide that + * info by keeping a crazy value for ESR in r14 + */ + li r14,-1 /* store to exception frame is done later */ + + /* Now we handle the fault proper. We only save DEAR in the non + * linear mapping case since we know the linear mapping case will + * not re-enter. We could indeed optimize and also not save SRR0/1 + * in the linear mapping case but I'll leave that for later + * + * Faulting address is SRR0 which is already in r16 + */ + srdi r11,r16,44 /* get region */ + xoris r11,r11,0xc + cmpldi cr0,r11,0 /* linear mapping ? */ + beq tlb_load_linear /* yes -> go to linear map load */ + cmpldi cr1,r11,1 /* vmalloc mapping ? */ + + /* We do the user/kernel test for the PID here along with the RW test + */ + srdi. r11,r16,60 /* Check for user region */ + ld r15,PACAPGD(r13) /* Load user pgdir */ + beq htw_tlb_miss + + /* XXX replace the RMW cycles with immediate loads + writes */ +1: mfspr r10,SPRN_MAS1 + rlwinm r10,r10,0,16,1 /* Clear TID */ + mtspr SPRN_MAS1,r10 + ld r15,PACA_KERNELPGD(r13) /* Load kernel pgdir */ + beq+ htw_tlb_miss + + /* We got a crappy address, just fault */ + TLB_MISS_EPILOG_ERROR + b exc_instruction_storage_book3e + + +/* + * This is the guts of the second-level TLB miss handler for direct + * misses. We are entered with: + * + * r16 = virtual page table faulting address + * r15 = PGD pointer + * r14 = ESR + * r13 = PACA + * r12 = TLB exception frame in PACA + * r11 = crap (free to use) + * r10 = crap (free to use) + * + * It can be re-entered by the linear mapping miss handler. However, to + * avoid too much complication, it will save/restore things for us + */ +htw_tlb_miss: +#ifdef CONFIG_PPC_KUAP + mfspr r10,SPRN_MAS1 + rlwinm. r10,r10,0,0x3fff0000 + beq- htw_tlb_miss_fault /* KUAP fault */ +#endif + /* Search if we already have a TLB entry for that virtual address, and + * if we do, bail out. + * + * MAS1:IND should be already set based on MAS4 + */ + PPC_TLBSRX_DOT(0,R16) + beq htw_tlb_miss_done + + /* Now, we need to walk the page tables. First check if we are in + * range. + */ + rldicl. r10,r16,64-PGTABLE_EADDR_SIZE,PGTABLE_EADDR_SIZE+4 + bne- htw_tlb_miss_fault + + /* Get the PGD pointer */ + cmpldi cr0,r15,0 + beq- htw_tlb_miss_fault + + /* Get to PGD entry */ + rldicl r11,r16,64-(PGDIR_SHIFT-3),64-PGD_INDEX_SIZE-3 + clrrdi r10,r11,3 + ldx r15,r10,r15 + cmpdi cr0,r15,0 + bge htw_tlb_miss_fault + + /* Get to PUD entry */ + rldicl r11,r16,64-(PUD_SHIFT-3),64-PUD_INDEX_SIZE-3 + clrrdi r10,r11,3 + ldx r15,r10,r15 + cmpdi cr0,r15,0 + bge htw_tlb_miss_fault + + /* Get to PMD entry */ + rldicl r11,r16,64-(PMD_SHIFT-3),64-PMD_INDEX_SIZE-3 + clrrdi r10,r11,3 + ldx r15,r10,r15 + cmpdi cr0,r15,0 + bge htw_tlb_miss_fault + + /* Ok, we're all right, we can now create an indirect entry for + * a 1M or 256M page. + * + * The last trick is now that because we use "half" pages for + * the HTW (1M IND is 2K and 256M IND is 32K) we need to account + * for an added LSB bit to the RPN. For 64K pages, there is no + * problem as we already use 32K arrays (half PTE pages), but for + * 4K page we need to extract a bit from the virtual address and + * insert it into the "PA52" bit of the RPN. + */ + rlwimi r15,r16,32-9,20,20 + /* Now we build the MAS: + * + * MAS 0 : Fully setup with defaults in MAS4 and TLBnCFG + * MAS 1 : Almost fully setup + * - PID already updated by caller if necessary + * - TSIZE for now is base ind page size always + * MAS 2 : Use defaults + * MAS 3+7 : Needs to be done + */ + ori r10,r15,(BOOK3E_PAGESZ_4K << MAS3_SPSIZE_SHIFT) + + srdi r16,r10,32 + mtspr SPRN_MAS3,r10 + mtspr SPRN_MAS7,r16 + + tlbwe + +htw_tlb_miss_done: + /* We don't bother with restoring DEAR or ESR since we know we are + * level 0 and just going back to userland. They are only needed + * if you are going to take an access fault + */ + TLB_MISS_EPILOG_SUCCESS + rfi + +htw_tlb_miss_fault: + /* We need to check if it was an instruction miss. We know this + * though because r14 would contain -1 + */ + cmpdi cr0,r14,-1 + beq 1f + mtspr SPRN_DEAR,r16 + mtspr SPRN_ESR,r14 + TLB_MISS_EPILOG_ERROR + b exc_data_storage_book3e +1: TLB_MISS_EPILOG_ERROR + b exc_instruction_storage_book3e + +/* + * This is the guts of "any" level TLB miss handler for kernel linear + * mapping misses. We are entered with: + * + * + * r16 = faulting address + * r15 = crap (free to use) + * r14 = ESR (data) or -1 (instruction) + * r13 = PACA + * r12 = TLB exception frame in PACA + * r11 = crap (free to use) + * r10 = crap (free to use) + * + * In addition we know that we will not re-enter, so in theory, we could + * use a simpler epilog not restoring SRR0/1 etc.. but we'll do that later. + * + * We also need to be careful about MAS registers here & TLB reservation, + * as we know we'll have clobbered them if we interrupt the main TLB miss + * handlers in which case we probably want to do a full restart at level + * 0 rather than saving / restoring the MAS. + * + * Note: If we care about performance of that core, we can easily shuffle + * a few things around + */ +tlb_load_linear: + /* For now, we assume the linear mapping is contiguous and stops at + * linear_map_top. We also assume the size is a multiple of 1G, thus + * we only use 1G pages for now. That might have to be changed in a + * final implementation, especially when dealing with hypervisors + */ + __LOAD_PACA_TOC(r11) + LOAD_REG_ADDR_ALTTOC(r11, r11, linear_map_top) + ld r10,0(r11) + tovirt(10,10) + cmpld cr0,r16,r10 + bge tlb_load_linear_fault + + /* MAS1 need whole new setup. */ + li r15,(BOOK3E_PAGESZ_1GB<<MAS1_TSIZE_SHIFT) + oris r15,r15,MAS1_VALID@h /* MAS1 needs V and TSIZE */ + mtspr SPRN_MAS1,r15 + + /* Already somebody there ? */ + PPC_TLBSRX_DOT(0,R16) + beq tlb_load_linear_done + + /* Now we build the remaining MAS. MAS0 and 2 should be fine + * with their defaults, which leaves us with MAS 3 and 7. The + * mapping is linear, so we just take the address, clear the + * region bits, and or in the permission bits which are currently + * hard wired + */ + clrrdi r10,r16,30 /* 1G page index */ + clrldi r10,r10,4 /* clear region bits */ + ori r10,r10,MAS3_SR|MAS3_SW|MAS3_SX + + srdi r16,r10,32 + mtspr SPRN_MAS3,r10 + mtspr SPRN_MAS7,r16 + + tlbwe + +tlb_load_linear_done: + /* We use the "error" epilog for success as we do want to + * restore to the initial faulting context, whatever it was. + * We do that because we can't resume a fault within a TLB + * miss handler, due to MAS and TLB reservation being clobbered. + */ + TLB_MISS_EPILOG_ERROR + rfi + +tlb_load_linear_fault: + /* We keep the DEAR and ESR around, this shouldn't have happened */ + cmpdi cr0,r14,-1 + beq 1f + TLB_MISS_EPILOG_ERROR_SPECIAL + b exc_data_storage_book3e +1: TLB_MISS_EPILOG_ERROR_SPECIAL + b exc_instruction_storage_book3e |