diff options
Diffstat (limited to 'arch/powerpc/kernel/paca.c')
-rw-r--r-- | arch/powerpc/kernel/paca.c | 323 |
1 files changed, 323 insertions, 0 deletions
diff --git a/arch/powerpc/kernel/paca.c b/arch/powerpc/kernel/paca.c new file mode 100644 index 0000000000..cda4e00b67 --- /dev/null +++ b/arch/powerpc/kernel/paca.c @@ -0,0 +1,323 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * c 2001 PPC 64 Team, IBM Corp + */ + +#include <linux/smp.h> +#include <linux/export.h> +#include <linux/memblock.h> +#include <linux/sched/task.h> +#include <linux/numa.h> +#include <linux/pgtable.h> + +#include <asm/lppaca.h> +#include <asm/paca.h> +#include <asm/sections.h> +#include <asm/kexec.h> +#include <asm/svm.h> +#include <asm/ultravisor.h> + +#include "setup.h" + +#ifndef CONFIG_SMP +#define boot_cpuid 0 +#endif + +static void *__init alloc_paca_data(unsigned long size, unsigned long align, + unsigned long limit, int cpu) +{ + void *ptr; + int nid; + + /* + * boot_cpuid paca is allocated very early before cpu_to_node is up. + * Set bottom-up mode, because the boot CPU should be on node-0, + * which will put its paca in the right place. + */ + if (cpu == boot_cpuid) { + nid = NUMA_NO_NODE; + memblock_set_bottom_up(true); + } else { + nid = early_cpu_to_node(cpu); + } + + ptr = memblock_alloc_try_nid(size, align, MEMBLOCK_LOW_LIMIT, + limit, nid); + if (!ptr) + panic("cannot allocate paca data"); + + if (cpu == boot_cpuid) + memblock_set_bottom_up(false); + + return ptr; +} + +#ifdef CONFIG_PPC_PSERIES + +#define LPPACA_SIZE 0x400 + +static void *__init alloc_shared_lppaca(unsigned long size, unsigned long limit, + int cpu) +{ + size_t shared_lppaca_total_size = PAGE_ALIGN(nr_cpu_ids * LPPACA_SIZE); + static unsigned long shared_lppaca_size; + static void *shared_lppaca; + void *ptr; + + if (!shared_lppaca) { + memblock_set_bottom_up(true); + + /* + * See Documentation/powerpc/ultravisor.rst for more details. + * + * UV/HV data sharing is in PAGE_SIZE granularity. In order to + * minimize the number of pages shared, align the allocation to + * PAGE_SIZE. + */ + shared_lppaca = + memblock_alloc_try_nid(shared_lppaca_total_size, + PAGE_SIZE, MEMBLOCK_LOW_LIMIT, + limit, NUMA_NO_NODE); + if (!shared_lppaca) + panic("cannot allocate shared data"); + + memblock_set_bottom_up(false); + uv_share_page(PHYS_PFN(__pa(shared_lppaca)), + shared_lppaca_total_size >> PAGE_SHIFT); + } + + ptr = shared_lppaca + shared_lppaca_size; + shared_lppaca_size += size; + + /* + * This is very early in boot, so no harm done if the kernel crashes at + * this point. + */ + BUG_ON(shared_lppaca_size > shared_lppaca_total_size); + + return ptr; +} + +/* + * See asm/lppaca.h for more detail. + * + * lppaca structures must must be 1kB in size, L1 cache line aligned, + * and not cross 4kB boundary. A 1kB size and 1kB alignment will satisfy + * these requirements. + */ +static inline void init_lppaca(struct lppaca *lppaca) +{ + BUILD_BUG_ON(sizeof(struct lppaca) != 640); + + *lppaca = (struct lppaca) { + .desc = cpu_to_be32(0xd397d781), /* "LpPa" */ + .size = cpu_to_be16(LPPACA_SIZE), + .fpregs_in_use = 1, + .slb_count = cpu_to_be16(64), + .vmxregs_in_use = 0, + .page_ins = 0, }; +}; + +static struct lppaca * __init new_lppaca(int cpu, unsigned long limit) +{ + struct lppaca *lp; + + BUILD_BUG_ON(sizeof(struct lppaca) > LPPACA_SIZE); + + if (early_cpu_has_feature(CPU_FTR_HVMODE)) + return NULL; + + if (is_secure_guest()) + lp = alloc_shared_lppaca(LPPACA_SIZE, limit, cpu); + else + lp = alloc_paca_data(LPPACA_SIZE, 0x400, limit, cpu); + + init_lppaca(lp); + + return lp; +} +#endif /* CONFIG_PPC_PSERIES */ + +#ifdef CONFIG_PPC_64S_HASH_MMU +/* + * 3 persistent SLBs are allocated here. The buffer will be zero + * initially, hence will all be invaild until we actually write them. + * + * If you make the number of persistent SLB entries dynamic, please also + * update PR KVM to flush and restore them accordingly. + */ +static struct slb_shadow * __init new_slb_shadow(int cpu, unsigned long limit) +{ + struct slb_shadow *s; + + if (cpu != boot_cpuid) { + /* + * Boot CPU comes here before early_radix_enabled + * is parsed (e.g., for disable_radix). So allocate + * always and this will be fixed up in free_unused_pacas. + */ + if (early_radix_enabled()) + return NULL; + } + + s = alloc_paca_data(sizeof(*s), L1_CACHE_BYTES, limit, cpu); + + s->persistent = cpu_to_be32(SLB_NUM_BOLTED); + s->buffer_length = cpu_to_be32(sizeof(*s)); + + return s; +} +#endif /* CONFIG_PPC_64S_HASH_MMU */ + +/* The Paca is an array with one entry per processor. Each contains an + * lppaca, which contains the information shared between the + * hypervisor and Linux. + * On systems with hardware multi-threading, there are two threads + * per processor. The Paca array must contain an entry for each thread. + * The VPD Areas will give a max logical processors = 2 * max physical + * processors. The processor VPD array needs one entry per physical + * processor (not thread). + */ +struct paca_struct **paca_ptrs __read_mostly; +EXPORT_SYMBOL(paca_ptrs); + +void __init initialise_paca(struct paca_struct *new_paca, int cpu) +{ +#ifdef CONFIG_PPC_PSERIES + new_paca->lppaca_ptr = NULL; +#endif +#ifdef CONFIG_PPC_BOOK3E_64 + new_paca->kernel_pgd = swapper_pg_dir; +#endif + new_paca->lock_token = 0x8000; + new_paca->paca_index = cpu; +#ifndef CONFIG_PPC_KERNEL_PCREL + new_paca->kernel_toc = kernel_toc_addr(); +#endif + new_paca->kernelbase = (unsigned long) _stext; + /* Only set MSR:IR/DR when MMU is initialized */ + new_paca->kernel_msr = MSR_KERNEL & ~(MSR_IR | MSR_DR); + new_paca->hw_cpu_id = 0xffff; + new_paca->kexec_state = KEXEC_STATE_NONE; + new_paca->__current = &init_task; + new_paca->data_offset = 0xfeeeeeeeeeeeeeeeULL; +#ifdef CONFIG_PPC_64S_HASH_MMU + new_paca->slb_shadow_ptr = NULL; +#endif + +#ifdef CONFIG_PPC_BOOK3E_64 + /* For now -- if we have threads this will be adjusted later */ + new_paca->tcd_ptr = &new_paca->tcd; +#endif +} + +/* Put the paca pointer into r13 and SPRG_PACA */ +void setup_paca(struct paca_struct *new_paca) +{ + /* Setup r13 */ + local_paca = new_paca; + +#ifdef CONFIG_PPC_BOOK3E_64 + /* On Book3E, initialize the TLB miss exception frames */ + mtspr(SPRN_SPRG_TLB_EXFRAME, local_paca->extlb); +#else + /* + * In HV mode, we setup both HPACA and PACA to avoid problems + * if we do a GET_PACA() before the feature fixups have been + * applied. + * + * Normally you should test against CPU_FTR_HVMODE, but CPU features + * are not yet set up when we first reach here. + */ + if (mfmsr() & MSR_HV) + mtspr(SPRN_SPRG_HPACA, local_paca); +#endif + mtspr(SPRN_SPRG_PACA, local_paca); + +} + +static int __initdata paca_nr_cpu_ids; +static int __initdata paca_ptrs_size; +static int __initdata paca_struct_size; + +void __init allocate_paca_ptrs(void) +{ + paca_nr_cpu_ids = nr_cpu_ids; + + paca_ptrs_size = sizeof(struct paca_struct *) * nr_cpu_ids; + paca_ptrs = memblock_alloc_raw(paca_ptrs_size, SMP_CACHE_BYTES); + if (!paca_ptrs) + panic("Failed to allocate %d bytes for paca pointers\n", + paca_ptrs_size); + + memset(paca_ptrs, 0x88, paca_ptrs_size); +} + +void __init allocate_paca(int cpu) +{ + u64 limit; + struct paca_struct *paca; + + BUG_ON(cpu >= paca_nr_cpu_ids); + +#ifdef CONFIG_PPC_BOOK3S_64 + /* + * We access pacas in real mode, and cannot take SLB faults + * on them when in virtual mode, so allocate them accordingly. + */ + limit = min(ppc64_bolted_size(), ppc64_rma_size); +#else + limit = ppc64_rma_size; +#endif + + paca = alloc_paca_data(sizeof(struct paca_struct), L1_CACHE_BYTES, + limit, cpu); + paca_ptrs[cpu] = paca; + + initialise_paca(paca, cpu); +#ifdef CONFIG_PPC_PSERIES + paca->lppaca_ptr = new_lppaca(cpu, limit); +#endif +#ifdef CONFIG_PPC_64S_HASH_MMU + paca->slb_shadow_ptr = new_slb_shadow(cpu, limit); +#endif + paca_struct_size += sizeof(struct paca_struct); +} + +void __init free_unused_pacas(void) +{ + int new_ptrs_size; + + new_ptrs_size = sizeof(struct paca_struct *) * nr_cpu_ids; + if (new_ptrs_size < paca_ptrs_size) + memblock_phys_free(__pa(paca_ptrs) + new_ptrs_size, + paca_ptrs_size - new_ptrs_size); + + paca_nr_cpu_ids = nr_cpu_ids; + paca_ptrs_size = new_ptrs_size; + +#ifdef CONFIG_PPC_64S_HASH_MMU + if (early_radix_enabled()) { + /* Ugly fixup, see new_slb_shadow() */ + memblock_phys_free(__pa(paca_ptrs[boot_cpuid]->slb_shadow_ptr), + sizeof(struct slb_shadow)); + paca_ptrs[boot_cpuid]->slb_shadow_ptr = NULL; + } +#endif + + printk(KERN_DEBUG "Allocated %u bytes for %u pacas\n", + paca_ptrs_size + paca_struct_size, nr_cpu_ids); +} + +#ifdef CONFIG_PPC_64S_HASH_MMU +void copy_mm_to_paca(struct mm_struct *mm) +{ + mm_context_t *context = &mm->context; + + VM_BUG_ON(!mm_ctx_slb_addr_limit(context)); + memcpy(&get_paca()->mm_ctx_low_slices_psize, mm_ctx_low_slices(context), + LOW_SLICE_ARRAY_SZ); + memcpy(&get_paca()->mm_ctx_high_slices_psize, mm_ctx_high_slices(context), + TASK_SLICE_ARRAY_SZ(context)); +} +#endif /* CONFIG_PPC_64S_HASH_MMU */ |