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Diffstat (limited to 'arch/arm/mm/proc-arm940.S')
| -rw-r--r-- | arch/arm/mm/proc-arm940.S | 360 |
1 files changed, 360 insertions, 0 deletions
diff --git a/arch/arm/mm/proc-arm940.S b/arch/arm/mm/proc-arm940.S new file mode 100644 index 000000000..cf9bfcc82 --- /dev/null +++ b/arch/arm/mm/proc-arm940.S @@ -0,0 +1,360 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* + * linux/arch/arm/mm/arm940.S: utility functions for ARM940T + * + * Copyright (C) 2004-2006 Hyok S. Choi (hyok.choi@samsung.com) + */ +#include <linux/linkage.h> +#include <linux/init.h> +#include <linux/pgtable.h> +#include <asm/assembler.h> +#include <asm/hwcap.h> +#include <asm/pgtable-hwdef.h> +#include <asm/ptrace.h> +#include "proc-macros.S" + +/* ARM940T has a 4KB DCache comprising 256 lines of 4 words */ +#define CACHE_DLINESIZE 16 +#define CACHE_DSEGMENTS 4 +#define CACHE_DENTRIES 64 + + .text +/* + * cpu_arm940_proc_init() + * cpu_arm940_switch_mm() + * + * These are not required. + */ +ENTRY(cpu_arm940_proc_init) +ENTRY(cpu_arm940_switch_mm) + ret lr + +/* + * cpu_arm940_proc_fin() + */ +ENTRY(cpu_arm940_proc_fin) + mrc p15, 0, r0, c1, c0, 0 @ ctrl register + bic r0, r0, #0x00001000 @ i-cache + bic r0, r0, #0x00000004 @ d-cache + mcr p15, 0, r0, c1, c0, 0 @ disable caches + ret lr + +/* + * cpu_arm940_reset(loc) + * Params : r0 = address to jump to + * Notes : This sets up everything for a reset + */ + .pushsection .idmap.text, "ax" +ENTRY(cpu_arm940_reset) + mov ip, #0 + mcr p15, 0, ip, c7, c5, 0 @ flush I cache + mcr p15, 0, ip, c7, c6, 0 @ flush D cache + mcr p15, 0, ip, c7, c10, 4 @ drain WB + mrc p15, 0, ip, c1, c0, 0 @ ctrl register + bic ip, ip, #0x00000005 @ .............c.p + bic ip, ip, #0x00001000 @ i-cache + mcr p15, 0, ip, c1, c0, 0 @ ctrl register + ret r0 +ENDPROC(cpu_arm940_reset) + .popsection + +/* + * cpu_arm940_do_idle() + */ + .align 5 +ENTRY(cpu_arm940_do_idle) + mcr p15, 0, r0, c7, c0, 4 @ Wait for interrupt + ret lr + +/* + * flush_icache_all() + * + * Unconditionally clean and invalidate the entire icache. + */ +ENTRY(arm940_flush_icache_all) + mov r0, #0 + mcr p15, 0, r0, c7, c5, 0 @ invalidate I cache + ret lr +ENDPROC(arm940_flush_icache_all) + +/* + * flush_user_cache_all() + */ +ENTRY(arm940_flush_user_cache_all) + /* FALLTHROUGH */ + +/* + * flush_kern_cache_all() + * + * Clean and invalidate the entire cache. + */ +ENTRY(arm940_flush_kern_cache_all) + mov r2, #VM_EXEC + /* FALLTHROUGH */ + +/* + * flush_user_cache_range(start, end, flags) + * + * There is no efficient way to flush a range of cache entries + * in the specified address range. Thus, flushes all. + * + * - start - start address (inclusive) + * - end - end address (exclusive) + * - flags - vm_flags describing address space + */ +ENTRY(arm940_flush_user_cache_range) + mov ip, #0 +#ifdef CONFIG_CPU_DCACHE_WRITETHROUGH + mcr p15, 0, ip, c7, c6, 0 @ flush D cache +#else + mov r1, #(CACHE_DSEGMENTS - 1) << 4 @ 4 segments +1: orr r3, r1, #(CACHE_DENTRIES - 1) << 26 @ 64 entries +2: mcr p15, 0, r3, c7, c14, 2 @ clean/flush D index + subs r3, r3, #1 << 26 + bcs 2b @ entries 63 to 0 + subs r1, r1, #1 << 4 + bcs 1b @ segments 3 to 0 +#endif + tst r2, #VM_EXEC + mcrne p15, 0, ip, c7, c5, 0 @ invalidate I cache + mcrne p15, 0, ip, c7, c10, 4 @ drain WB + ret lr + +/* + * coherent_kern_range(start, end) + * + * Ensure coherency between the Icache and the Dcache in the + * region described by start, end. If you have non-snooping + * Harvard caches, you need to implement this function. + * + * - start - virtual start address + * - end - virtual end address + */ +ENTRY(arm940_coherent_kern_range) + /* FALLTHROUGH */ + +/* + * coherent_user_range(start, end) + * + * Ensure coherency between the Icache and the Dcache in the + * region described by start, end. If you have non-snooping + * Harvard caches, you need to implement this function. + * + * - start - virtual start address + * - end - virtual end address + */ +ENTRY(arm940_coherent_user_range) + /* FALLTHROUGH */ + +/* + * flush_kern_dcache_area(void *addr, size_t size) + * + * Ensure no D cache aliasing occurs, either with itself or + * the I cache + * + * - addr - kernel address + * - size - region size + */ +ENTRY(arm940_flush_kern_dcache_area) + mov r0, #0 + mov r1, #(CACHE_DSEGMENTS - 1) << 4 @ 4 segments +1: orr r3, r1, #(CACHE_DENTRIES - 1) << 26 @ 64 entries +2: mcr p15, 0, r3, c7, c14, 2 @ clean/flush D index + subs r3, r3, #1 << 26 + bcs 2b @ entries 63 to 0 + subs r1, r1, #1 << 4 + bcs 1b @ segments 7 to 0 + mcr p15, 0, r0, c7, c5, 0 @ invalidate I cache + mcr p15, 0, r0, c7, c10, 4 @ drain WB + ret lr + +/* + * dma_inv_range(start, end) + * + * There is no efficient way to invalidate a specifid virtual + * address range. Thus, invalidates all. + * + * - start - virtual start address + * - end - virtual end address + */ +arm940_dma_inv_range: + mov ip, #0 + mov r1, #(CACHE_DSEGMENTS - 1) << 4 @ 4 segments +1: orr r3, r1, #(CACHE_DENTRIES - 1) << 26 @ 64 entries +2: mcr p15, 0, r3, c7, c6, 2 @ flush D entry + subs r3, r3, #1 << 26 + bcs 2b @ entries 63 to 0 + subs r1, r1, #1 << 4 + bcs 1b @ segments 7 to 0 + mcr p15, 0, ip, c7, c10, 4 @ drain WB + ret lr + +/* + * dma_clean_range(start, end) + * + * There is no efficient way to clean a specifid virtual + * address range. Thus, cleans all. + * + * - start - virtual start address + * - end - virtual end address + */ +arm940_dma_clean_range: +ENTRY(cpu_arm940_dcache_clean_area) + mov ip, #0 +#ifndef CONFIG_CPU_DCACHE_WRITETHROUGH + mov r1, #(CACHE_DSEGMENTS - 1) << 4 @ 4 segments +1: orr r3, r1, #(CACHE_DENTRIES - 1) << 26 @ 64 entries +2: mcr p15, 0, r3, c7, c10, 2 @ clean D entry + subs r3, r3, #1 << 26 + bcs 2b @ entries 63 to 0 + subs r1, r1, #1 << 4 + bcs 1b @ segments 7 to 0 +#endif + mcr p15, 0, ip, c7, c10, 4 @ drain WB + ret lr + +/* + * dma_flush_range(start, end) + * + * There is no efficient way to clean and invalidate a specifid + * virtual address range. + * + * - start - virtual start address + * - end - virtual end address + */ +ENTRY(arm940_dma_flush_range) + mov ip, #0 + mov r1, #(CACHE_DSEGMENTS - 1) << 4 @ 4 segments +1: orr r3, r1, #(CACHE_DENTRIES - 1) << 26 @ 64 entries +2: +#ifndef CONFIG_CPU_DCACHE_WRITETHROUGH + mcr p15, 0, r3, c7, c14, 2 @ clean/flush D entry +#else + mcr p15, 0, r3, c7, c6, 2 @ invalidate D entry +#endif + subs r3, r3, #1 << 26 + bcs 2b @ entries 63 to 0 + subs r1, r1, #1 << 4 + bcs 1b @ segments 7 to 0 + mcr p15, 0, ip, c7, c10, 4 @ drain WB + ret lr + +/* + * dma_map_area(start, size, dir) + * - start - kernel virtual start address + * - size - size of region + * - dir - DMA direction + */ +ENTRY(arm940_dma_map_area) + add r1, r1, r0 + cmp r2, #DMA_TO_DEVICE + beq arm940_dma_clean_range + bcs arm940_dma_inv_range + b arm940_dma_flush_range +ENDPROC(arm940_dma_map_area) + +/* + * dma_unmap_area(start, size, dir) + * - start - kernel virtual start address + * - size - size of region + * - dir - DMA direction + */ +ENTRY(arm940_dma_unmap_area) + ret lr +ENDPROC(arm940_dma_unmap_area) + + .globl arm940_flush_kern_cache_louis + .equ arm940_flush_kern_cache_louis, arm940_flush_kern_cache_all + + @ define struct cpu_cache_fns (see <asm/cacheflush.h> and proc-macros.S) + define_cache_functions arm940 + + .type __arm940_setup, #function +__arm940_setup: + mov r0, #0 + mcr p15, 0, r0, c7, c5, 0 @ invalidate I cache + mcr p15, 0, r0, c7, c6, 0 @ invalidate D cache + mcr p15, 0, r0, c7, c10, 4 @ drain WB + + mcr p15, 0, r0, c6, c3, 0 @ disable data area 3~7 + mcr p15, 0, r0, c6, c4, 0 + mcr p15, 0, r0, c6, c5, 0 + mcr p15, 0, r0, c6, c6, 0 + mcr p15, 0, r0, c6, c7, 0 + + mcr p15, 0, r0, c6, c3, 1 @ disable instruction area 3~7 + mcr p15, 0, r0, c6, c4, 1 + mcr p15, 0, r0, c6, c5, 1 + mcr p15, 0, r0, c6, c6, 1 + mcr p15, 0, r0, c6, c7, 1 + + mov r0, #0x0000003F @ base = 0, size = 4GB + mcr p15, 0, r0, c6, c0, 0 @ set area 0, default + mcr p15, 0, r0, c6, c0, 1 + + ldr r0, =(CONFIG_DRAM_BASE & 0xFFFFF000) @ base[31:12] of RAM + ldr r7, =CONFIG_DRAM_SIZE >> 12 @ size of RAM (must be >= 4KB) + pr_val r3, r0, r7, #1 + mcr p15, 0, r3, c6, c1, 0 @ set area 1, RAM + mcr p15, 0, r3, c6, c1, 1 + + ldr r0, =(CONFIG_FLASH_MEM_BASE & 0xFFFFF000) @ base[31:12] of FLASH + ldr r7, =CONFIG_FLASH_SIZE @ size of FLASH (must be >= 4KB) + pr_val r3, r0, r6, #1 + mcr p15, 0, r3, c6, c2, 0 @ set area 2, ROM/FLASH + mcr p15, 0, r3, c6, c2, 1 + + mov r0, #0x06 + mcr p15, 0, r0, c2, c0, 0 @ Region 1&2 cacheable + mcr p15, 0, r0, c2, c0, 1 +#ifdef CONFIG_CPU_DCACHE_WRITETHROUGH + mov r0, #0x00 @ disable whole write buffer +#else + mov r0, #0x02 @ Region 1 write bufferred +#endif + mcr p15, 0, r0, c3, c0, 0 + + mov r0, #0x10000 + sub r0, r0, #1 @ r0 = 0xffff + mcr p15, 0, r0, c5, c0, 0 @ all read/write access + mcr p15, 0, r0, c5, c0, 1 + + mrc p15, 0, r0, c1, c0 @ get control register + orr r0, r0, #0x00001000 @ I-cache + orr r0, r0, #0x00000005 @ MPU/D-cache + + ret lr + + .size __arm940_setup, . - __arm940_setup + + __INITDATA + + @ define struct processor (see <asm/proc-fns.h> and proc-macros.S) + define_processor_functions arm940, dabort=nommu_early_abort, pabort=legacy_pabort, nommu=1 + + .section ".rodata" + + string cpu_arch_name, "armv4t" + string cpu_elf_name, "v4" + string cpu_arm940_name, "ARM940T" + + .align + + .section ".proc.info.init", "a" + + .type __arm940_proc_info,#object +__arm940_proc_info: + .long 0x41009400 + .long 0xff00fff0 + .long 0 + initfn __arm940_setup, __arm940_proc_info + .long cpu_arch_name + .long cpu_elf_name + .long HWCAP_SWP | HWCAP_HALF | HWCAP_THUMB + .long cpu_arm940_name + .long arm940_processor_functions + .long 0 + .long 0 + .long arm940_cache_fns + .size __arm940_proc_info, . - __arm940_proc_info + |