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Diffstat (limited to 'arch/arm/mm/proc-v6.S')
| -rw-r--r-- | arch/arm/mm/proc-v6.S | 299 |
1 files changed, 299 insertions, 0 deletions
diff --git a/arch/arm/mm/proc-v6.S b/arch/arm/mm/proc-v6.S new file mode 100644 index 0000000000..203dff89ab --- /dev/null +++ b/arch/arm/mm/proc-v6.S @@ -0,0 +1,299 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* + * linux/arch/arm/mm/proc-v6.S + * + * Copyright (C) 2001 Deep Blue Solutions Ltd. + * Modified by Catalin Marinas for noMMU support + * + * This is the "shell" of the ARMv6 processor support. + */ +#include <linux/init.h> +#include <linux/linkage.h> +#include <linux/pgtable.h> +#include <asm/assembler.h> +#include <asm/asm-offsets.h> +#include <asm/hwcap.h> +#include <asm/pgtable-hwdef.h> + +#include "proc-macros.S" + +#define D_CACHE_LINE_SIZE 32 + +#define TTB_C (1 << 0) +#define TTB_S (1 << 1) +#define TTB_IMP (1 << 2) +#define TTB_RGN_NC (0 << 3) +#define TTB_RGN_WBWA (1 << 3) +#define TTB_RGN_WT (2 << 3) +#define TTB_RGN_WB (3 << 3) + +#define TTB_FLAGS_UP TTB_RGN_WBWA +#define PMD_FLAGS_UP PMD_SECT_WB +#define TTB_FLAGS_SMP TTB_RGN_WBWA|TTB_S +#define PMD_FLAGS_SMP PMD_SECT_WBWA|PMD_SECT_S + +.arch armv6 + +ENTRY(cpu_v6_proc_init) + ret lr + +ENTRY(cpu_v6_proc_fin) + mrc p15, 0, r0, c1, c0, 0 @ ctrl register + bic r0, r0, #0x1000 @ ...i............ + bic r0, r0, #0x0006 @ .............ca. + mcr p15, 0, r0, c1, c0, 0 @ disable caches + ret lr + +/* + * cpu_v6_reset(loc) + * + * Perform a soft reset of the system. Put the CPU into the + * same state as it would be if it had been reset, and branch + * to what would be the reset vector. + * + * - loc - location to jump to for soft reset + */ + .align 5 + .pushsection .idmap.text, "ax" +ENTRY(cpu_v6_reset) + mrc p15, 0, r1, c1, c0, 0 @ ctrl register + bic r1, r1, #0x1 @ ...............m + mcr p15, 0, r1, c1, c0, 0 @ disable MMU + mov r1, #0 + mcr p15, 0, r1, c7, c5, 4 @ ISB + ret r0 +ENDPROC(cpu_v6_reset) + .popsection + +/* + * cpu_v6_do_idle() + * + * Idle the processor (eg, wait for interrupt). + * + * IRQs are already disabled. + */ +ENTRY(cpu_v6_do_idle) + mov r1, #0 + mcr p15, 0, r1, c7, c10, 4 @ DWB - WFI may enter a low-power mode + mcr p15, 0, r1, c7, c0, 4 @ wait for interrupt + ret lr + +ENTRY(cpu_v6_dcache_clean_area) +1: mcr p15, 0, r0, c7, c10, 1 @ clean D entry + add r0, r0, #D_CACHE_LINE_SIZE + subs r1, r1, #D_CACHE_LINE_SIZE + bhi 1b + ret lr + +/* + * cpu_v6_switch_mm(pgd_phys, tsk) + * + * Set the translation table base pointer to be pgd_phys + * + * - pgd_phys - physical address of new TTB + * + * It is assumed that: + * - we are not using split page tables + */ +ENTRY(cpu_v6_switch_mm) +#ifdef CONFIG_MMU + mov r2, #0 + mmid r1, r1 @ get mm->context.id + ALT_SMP(orr r0, r0, #TTB_FLAGS_SMP) + ALT_UP(orr r0, r0, #TTB_FLAGS_UP) + mcr p15, 0, r2, c7, c5, 6 @ flush BTAC/BTB + mcr p15, 0, r2, c7, c10, 4 @ drain write buffer + mcr p15, 0, r0, c2, c0, 0 @ set TTB 0 +#ifdef CONFIG_PID_IN_CONTEXTIDR + mrc p15, 0, r2, c13, c0, 1 @ read current context ID + bic r2, r2, #0xff @ extract the PID + and r1, r1, #0xff + orr r1, r1, r2 @ insert into new context ID +#endif + mcr p15, 0, r1, c13, c0, 1 @ set context ID +#endif + ret lr + +/* + * cpu_v6_set_pte_ext(ptep, pte, ext) + * + * Set a level 2 translation table entry. + * + * - ptep - pointer to level 2 translation table entry + * (hardware version is stored at -1024 bytes) + * - pte - PTE value to store + * - ext - value for extended PTE bits + */ + armv6_mt_table cpu_v6 + +ENTRY(cpu_v6_set_pte_ext) +#ifdef CONFIG_MMU + armv6_set_pte_ext cpu_v6 +#endif + ret lr + +/* Suspend/resume support: taken from arch/arm/mach-s3c64xx/sleep.S */ +.globl cpu_v6_suspend_size +.equ cpu_v6_suspend_size, 4 * 6 +#ifdef CONFIG_ARM_CPU_SUSPEND +ENTRY(cpu_v6_do_suspend) + stmfd sp!, {r4 - r9, lr} + mrc p15, 0, r4, c13, c0, 0 @ FCSE/PID +#ifdef CONFIG_MMU + mrc p15, 0, r5, c3, c0, 0 @ Domain ID + mrc p15, 0, r6, c2, c0, 1 @ Translation table base 1 +#endif + mrc p15, 0, r7, c1, c0, 1 @ auxiliary control register + mrc p15, 0, r8, c1, c0, 2 @ co-processor access control + mrc p15, 0, r9, c1, c0, 0 @ control register + stmia r0, {r4 - r9} + ldmfd sp!, {r4- r9, pc} +ENDPROC(cpu_v6_do_suspend) + +ENTRY(cpu_v6_do_resume) + mov ip, #0 + mcr p15, 0, ip, c7, c14, 0 @ clean+invalidate D cache + mcr p15, 0, ip, c7, c5, 0 @ invalidate I cache + mcr p15, 0, ip, c7, c15, 0 @ clean+invalidate cache + mcr p15, 0, ip, c7, c10, 4 @ drain write buffer + mcr p15, 0, ip, c13, c0, 1 @ set reserved context ID + ldmia r0, {r4 - r9} + mcr p15, 0, r4, c13, c0, 0 @ FCSE/PID +#ifdef CONFIG_MMU + mcr p15, 0, r5, c3, c0, 0 @ Domain ID + ALT_SMP(orr r1, r1, #TTB_FLAGS_SMP) + ALT_UP(orr r1, r1, #TTB_FLAGS_UP) + mcr p15, 0, r1, c2, c0, 0 @ Translation table base 0 + mcr p15, 0, r6, c2, c0, 1 @ Translation table base 1 + mcr p15, 0, ip, c2, c0, 2 @ TTB control register +#endif + mcr p15, 0, r7, c1, c0, 1 @ auxiliary control register + mcr p15, 0, r8, c1, c0, 2 @ co-processor access control + mcr p15, 0, ip, c7, c5, 4 @ ISB + mov r0, r9 @ control register + b cpu_resume_mmu +ENDPROC(cpu_v6_do_resume) +#endif + + string cpu_v6_name, "ARMv6-compatible processor" + + .align + +/* + * __v6_setup + * + * Initialise TLB, Caches, and MMU state ready to switch the MMU + * on. Return in r0 the new CP15 C1 control register setting. + * + * We automatically detect if we have a Harvard cache, and use the + * Harvard cache control instructions insead of the unified cache + * control instructions. + * + * This should be able to cover all ARMv6 cores. + * + * It is assumed that: + * - cache type register is implemented + */ +__v6_setup: +#ifdef CONFIG_SMP + ALT_SMP(mrc p15, 0, r0, c1, c0, 1) @ Enable SMP/nAMP mode + ALT_UP(nop) + orr r0, r0, #0x20 + ALT_SMP(mcr p15, 0, r0, c1, c0, 1) + ALT_UP(nop) +#endif + + mov r0, #0 + mcr p15, 0, r0, c7, c14, 0 @ clean+invalidate D cache + mcr p15, 0, r0, c7, c5, 0 @ invalidate I cache + mcr p15, 0, r0, c7, c15, 0 @ clean+invalidate cache +#ifdef CONFIG_MMU + mcr p15, 0, r0, c8, c7, 0 @ invalidate I + D TLBs + mcr p15, 0, r0, c2, c0, 2 @ TTB control register + ALT_SMP(orr r4, r4, #TTB_FLAGS_SMP) + ALT_UP(orr r4, r4, #TTB_FLAGS_UP) + ALT_SMP(orr r8, r8, #TTB_FLAGS_SMP) + ALT_UP(orr r8, r8, #TTB_FLAGS_UP) + mcr p15, 0, r8, c2, c0, 1 @ load TTB1 +#endif /* CONFIG_MMU */ + mcr p15, 0, r0, c7, c10, 4 @ drain write buffer and + @ complete invalidations + adr r5, v6_crval + ldmia r5, {r5, r6} + ARM_BE8(orr r6, r6, #1 << 25) @ big-endian page tables + mrc p15, 0, r0, c1, c0, 0 @ read control register + bic r0, r0, r5 @ clear bits them + orr r0, r0, r6 @ set them +#ifdef CONFIG_ARM_ERRATA_364296 + /* + * Workaround for the 364296 ARM1136 r0p2 erratum (possible cache data + * corruption with hit-under-miss enabled). The conditional code below + * (setting the undocumented bit 31 in the auxiliary control register + * and the FI bit in the control register) disables hit-under-miss + * without putting the processor into full low interrupt latency mode. + */ + ldr r6, =0x4107b362 @ id for ARM1136 r0p2 + mrc p15, 0, r5, c0, c0, 0 @ get processor id + teq r5, r6 @ check for the faulty core + mrceq p15, 0, r5, c1, c0, 1 @ load aux control reg + orreq r5, r5, #(1 << 31) @ set the undocumented bit 31 + mcreq p15, 0, r5, c1, c0, 1 @ write aux control reg + orreq r0, r0, #(1 << 21) @ low interrupt latency configuration +#endif + ret lr @ return to head.S:__ret + + /* + * V X F I D LR + * .... ...E PUI. .T.T 4RVI ZFRS BLDP WCAM + * rrrr rrrx xxx0 0101 xxxx xxxx x111 xxxx < forced + * 0 110 0011 1.00 .111 1101 < we want + */ + .type v6_crval, #object +v6_crval: + crval clear=0x01e0fb7f, mmuset=0x00c0387d, ucset=0x00c0187c + + __INITDATA + + @ define struct processor (see <asm/proc-fns.h> and proc-macros.S) + define_processor_functions v6, dabort=v6_early_abort, pabort=v6_pabort, suspend=1 + + .section ".rodata" + + string cpu_arch_name, "armv6" + string cpu_elf_name, "v6" + .align + + .section ".proc.info.init", "a" + + /* + * Match any ARMv6 processor core. + */ + .type __v6_proc_info, #object +__v6_proc_info: + .long 0x0007b000 + .long 0x0007f000 + ALT_SMP(.long \ + PMD_TYPE_SECT | \ + PMD_SECT_AP_WRITE | \ + PMD_SECT_AP_READ | \ + PMD_FLAGS_SMP) + ALT_UP(.long \ + PMD_TYPE_SECT | \ + PMD_SECT_AP_WRITE | \ + PMD_SECT_AP_READ | \ + PMD_FLAGS_UP) + .long PMD_TYPE_SECT | \ + PMD_SECT_XN | \ + PMD_SECT_AP_WRITE | \ + PMD_SECT_AP_READ + initfn __v6_setup, __v6_proc_info + .long cpu_arch_name + .long cpu_elf_name + /* See also feat_v6_fixup() for HWCAP_TLS */ + .long HWCAP_SWP|HWCAP_HALF|HWCAP_THUMB|HWCAP_FAST_MULT|HWCAP_EDSP|HWCAP_JAVA|HWCAP_TLS + .long cpu_v6_name + .long v6_processor_functions + .long v6wbi_tlb_fns + .long v6_user_fns + .long v6_cache_fns + .size __v6_proc_info, . - __v6_proc_info |