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Diffstat (limited to 'arch/arm/mm/proc-xsc3.S')
| -rw-r--r-- | arch/arm/mm/proc-xsc3.S | 498 |
1 files changed, 498 insertions, 0 deletions
diff --git a/arch/arm/mm/proc-xsc3.S b/arch/arm/mm/proc-xsc3.S new file mode 100644 index 00000000000..f90513e9af0 --- /dev/null +++ b/arch/arm/mm/proc-xsc3.S @@ -0,0 +1,498 @@ +/* + * linux/arch/arm/mm/proc-xsc3.S + * + * Original Author: Matthew Gilbert + * Current Maintainer: Deepak Saxena <dsaxena@plexity.net> + * + * Copyright 2004 (C) Intel Corp. + * Copyright 2005 (c) MontaVista Software, Inc. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + * MMU functions for the Intel XScale3 Core (XSC3). The XSC3 core is an + * extension to Intel's original XScale core that adds the following + * features: + * + * - ARMv6 Supersections + * - Low Locality Reference pages (replaces mini-cache) + * - 36-bit addressing + * - L2 cache + * - Cache-coherency if chipset supports it + * + * Based on orignal XScale code by Nicolas Pitre + */ + +#include <linux/linkage.h> +#include <linux/init.h> +#include <asm/assembler.h> +#include <asm/procinfo.h> +#include <asm/hardware.h> +#include <asm/pgtable.h> +#include <asm/page.h> +#include <asm/ptrace.h> +#include "proc-macros.S" + +/* + * This is the maximum size of an area which will be flushed. If the + * area is larger than this, then we flush the whole cache. + */ +#define MAX_AREA_SIZE 32768 + +/* + * The cache line size of the I and D cache. + */ +#define CACHELINESIZE 32 + +/* + * The size of the data cache. + */ +#define CACHESIZE 32768 + +/* + * Run with L2 enabled. + */ +#define L2_CACHE_ENABLE 1 + +/* + * Enable the Branch Target Buffer (can cause crashes, see erratum #42.) + */ +#define BTB_ENABLE 0 + +/* + * This macro is used to wait for a CP15 write and is needed + * when we have to ensure that the last operation to the co-pro + * was completed before continuing with operation. + */ + .macro cpwait_ret, lr, rd + mrc p15, 0, \rd, c2, c0, 0 @ arbitrary read of cp15 + sub pc, \lr, \rd, LSR #32 @ wait for completion and + @ flush instruction pipeline + .endm + +/* + * This macro cleans & invalidates the entire xsc3 dcache by set & way. + */ + + .macro clean_d_cache rd, rs + mov \rd, #0x1f00 + orr \rd, \rd, #0x00e0 +1: mcr p15, 0, \rd, c7, c14, 2 @ clean/inv set/way + adds \rd, \rd, #0x40000000 + bcc 1b + subs \rd, \rd, #0x20 + bpl 1b + .endm + + .text + +/* + * cpu_xsc3_proc_init() + * + * Nothing too exciting at the moment + */ +ENTRY(cpu_xsc3_proc_init) + mov pc, lr + +/* + * cpu_xsc3_proc_fin() + */ +ENTRY(cpu_xsc3_proc_fin) + str lr, [sp, #-4]! + mov r0, #PSR_F_BIT|PSR_I_BIT|SVC_MODE + msr cpsr_c, r0 + bl xsc3_flush_kern_cache_all @ clean caches + mrc p15, 0, r0, c1, c0, 0 @ ctrl register + bic r0, r0, #0x1800 @ ...IZ........... + bic r0, r0, #0x0006 @ .............CA. + mcr p15, 0, r0, c1, c0, 0 @ disable caches + ldr pc, [sp], #4 + +/* + * cpu_xsc3_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 +ENTRY(cpu_xsc3_reset) + mov r1, #PSR_F_BIT|PSR_I_BIT|SVC_MODE + msr cpsr_c, r1 @ reset CPSR + mrc p15, 0, r1, c1, c0, 0 @ ctrl register + bic r1, r1, #0x0086 @ ........B....CA. + bic r1, r1, #0x3900 @ ..VIZ..S........ + mcr p15, 0, r1, c1, c0, 0 @ ctrl register + mcr p15, 0, ip, c7, c7, 0 @ invalidate I,D caches & BTB + bic r1, r1, #0x0001 @ ...............M + mcr p15, 0, r1, c1, c0, 0 @ ctrl register + @ CAUTION: MMU turned off from this point. We count on the pipeline + @ already containing those two last instructions to survive. + mcr p15, 0, ip, c8, c7, 0 @ invalidate I & D TLBs + mov pc, r0 + +/* + * cpu_xsc3_do_idle() + * + * Cause the processor to idle + * + * For now we do nothing but go to idle mode for every case + * + * XScale supports clock switching, but using idle mode support + * allows external hardware to react to system state changes. + + MMG: Come back to this one. + */ + .align 5 + +ENTRY(cpu_xsc3_do_idle) + mov r0, #1 + mcr p14, 0, r0, c7, c0, 0 @ Go to IDLE + mov pc, lr + +/* ================================= CACHE ================================ */ + +/* + * flush_user_cache_all() + * + * Invalidate all cache entries in a particular address + * space. + */ +ENTRY(xsc3_flush_user_cache_all) + /* FALLTHROUGH */ + +/* + * flush_kern_cache_all() + * + * Clean and invalidate the entire cache. + */ +ENTRY(xsc3_flush_kern_cache_all) + mov r2, #VM_EXEC + mov ip, #0 +__flush_whole_cache: + clean_d_cache r0, r1 + tst r2, #VM_EXEC + mcrne p15, 0, ip, c7, c5, 0 @ Invalidate I cache & BTB + mcrne p15, 0, ip, c7, c10, 4 @ Drain Write Buffer + mcrne p15, 0, ip, c7, c5, 4 @ Prefetch Flush + mov pc, lr + +/* + * flush_user_cache_range(start, end, vm_flags) + * + * Invalidate a range of cache entries in the specified + * address space. + * + * - start - start address (may not be aligned) + * - end - end address (exclusive, may not be aligned) + * - vma - vma_area_struct describing address space + */ + .align 5 +ENTRY(xsc3_flush_user_cache_range) + mov ip, #0 + sub r3, r1, r0 @ calculate total size + cmp r3, #MAX_AREA_SIZE + bhs __flush_whole_cache + +1: tst r2, #VM_EXEC + mcrne p15, 0, r0, c7, c5, 1 @ Invalidate I cache line + mcr p15, 0, r0, c7, c14, 1 @ Clean/invalidate D cache line + add r0, r0, #CACHELINESIZE + cmp r0, r1 + blo 1b + tst r2, #VM_EXEC + mcrne p15, 0, ip, c7, c5, 6 @ Invalidate BTB + mcrne p15, 0, ip, c7, c10, 4 @ Drain Write Buffer + mcrne p15, 0, ip, c7, c5, 4 @ Prefetch Flush + mov pc, lr + +/* + * coherent_kern_range(start, end) + * + * Ensure coherency between the Icache and the Dcache in the + * region described by start. If you have non-snooping + * Harvard caches, you need to implement this function. + * + * - start - virtual start address + * - end - virtual end address + * + * Note: single I-cache line invalidation isn't used here since + * it also trashes the mini I-cache used by JTAG debuggers. + */ +ENTRY(xsc3_coherent_kern_range) +/* FALLTHROUGH */ +ENTRY(xsc3_coherent_user_range) + bic r0, r0, #CACHELINESIZE - 1 +1: mcr p15, 0, r0, c7, c10, 1 @ clean D entry + add r0, r0, #CACHELINESIZE + cmp r0, r1 + blo 1b + mov r0, #0 + mcr p15, 0, r0, c7, c5, 0 @ Invalidate I cache & BTB + mcr p15, 0, r0, c7, c10, 4 @ Drain Write Buffer + mcr p15, 0, r0, c7, c5, 4 @ Prefetch Flush + mov pc, lr + +/* + * flush_kern_dcache_page(void *page) + * + * Ensure no D cache aliasing occurs, either with itself or + * the I cache + * + * - addr - page aligned address + */ +ENTRY(xsc3_flush_kern_dcache_page) + add r1, r0, #PAGE_SZ +1: mcr p15, 0, r0, c7, c14, 1 @ Clean/Invalidate D Cache line + add r0, r0, #CACHELINESIZE + cmp r0, r1 + blo 1b + mov r0, #0 + mcr p15, 0, r0, c7, c5, 0 @ Invalidate I cache & BTB + mcr p15, 0, r0, c7, c10, 4 @ Drain Write Buffer + mcr p15, 0, r0, c7, c5, 4 @ Prefetch Flush + mov pc, lr + +/* + * dma_inv_range(start, end) + * + * Invalidate (discard) the specified virtual address range. + * May not write back any entries. If 'start' or 'end' + * are not cache line aligned, those lines must be written + * back. + * + * - start - virtual start address + * - end - virtual end address + */ +ENTRY(xsc3_dma_inv_range) + tst r0, #CACHELINESIZE - 1 + bic r0, r0, #CACHELINESIZE - 1 + mcrne p15, 0, r0, c7, c10, 1 @ clean L1 D entry + mcrne p15, 1, r0, c7, c11, 1 @ clean L2 D entry + tst r1, #CACHELINESIZE - 1 + mcrne p15, 0, r1, c7, c10, 1 @ clean L1 D entry + mcrne p15, 1, r1, c7, c11, 1 @ clean L2 D entry +1: mcr p15, 0, r0, c7, c6, 1 @ invalidate L1 D entry + mcr p15, 1, r0, c7, c7, 1 @ Invalidate L2 D cache line + add r0, r0, #CACHELINESIZE + cmp r0, r1 + blo 1b + mcr p15, 0, r0, c7, c10, 4 @ Drain Write Buffer + mov pc, lr + +/* + * dma_clean_range(start, end) + * + * Clean the specified virtual address range. + * + * - start - virtual start address + * - end - virtual end address + */ +ENTRY(xsc3_dma_clean_range) + bic r0, r0, #CACHELINESIZE - 1 +1: mcr p15, 0, r0, c7, c10, 1 @ clean L1 D entry + mcr p15, 1, r0, c7, c11, 1 @ clean L2 D entry + add r0, r0, #CACHELINESIZE + cmp r0, r1 + blo 1b + mcr p15, 0, r0, c7, c10, 4 @ Drain Write Buffer + mov pc, lr + +/* + * dma_flush_range(start, end) + * + * Clean and invalidate the specified virtual address range. + * + * - start - virtual start address + * - end - virtual end address + */ +ENTRY(xsc3_dma_flush_range) + bic r0, r0, #CACHELINESIZE - 1 +1: mcr p15, 0, r0, c7, c14, 1 @ Clean/invalidate L1 D cache line + mcr p15, 1, r0, c7, c11, 1 @ Clean L2 D cache line + mcr p15, 1, r0, c7, c7, 1 @ Invalidate L2 D cache line + add r0, r0, #CACHELINESIZE + cmp r0, r1 + blo 1b + mcr p15, 0, r0, c7, c10, 4 @ Drain Write Buffer + mov pc, lr + +ENTRY(xsc3_cache_fns) + .long xsc3_flush_kern_cache_all + .long xsc3_flush_user_cache_all + .long xsc3_flush_user_cache_range + .long xsc3_coherent_kern_range + .long xsc3_coherent_user_range + .long xsc3_flush_kern_dcache_page + .long xsc3_dma_inv_range + .long xsc3_dma_clean_range + .long xsc3_dma_flush_range + +ENTRY(cpu_xsc3_dcache_clean_area) +1: mcr p15, 0, r0, c7, c10, 1 @ clean D entry + add r0, r0, #CACHELINESIZE + subs r1, r1, #CACHELINESIZE + bhi 1b + mov pc, lr + +/* =============================== PageTable ============================== */ + +/* + * cpu_xsc3_switch_mm(pgd) + * + * Set the translation base pointer to be as described by pgd. + * + * pgd: new page tables + */ + .align 5 +ENTRY(cpu_xsc3_switch_mm) + clean_d_cache r1, r2 + mcr p15, 0, ip, c7, c5, 0 @ Invalidate I cache & BTB + mcr p15, 0, ip, c7, c10, 4 @ Drain Write Buffer + mcr p15, 0, ip, c7, c5, 4 @ Prefetch Flush +#ifdef L2_CACHE_ENABLE + orr r0, r0, #0x18 @ cache the page table in L2 +#endif + mcr p15, 0, r0, c2, c0, 0 @ load page table pointer + mcr p15, 0, ip, c8, c7, 0 @ invalidate I & D TLBs + cpwait_ret lr, ip + +/* + * cpu_xsc3_set_pte(ptep, pte) + * + * Set a PTE and flush it out + * + */ + .align 5 +ENTRY(cpu_xsc3_set_pte) + str r1, [r0], #-2048 @ linux version + + bic r2, r1, #0xff0 + orr r2, r2, #PTE_TYPE_EXT @ extended page + + eor r3, r1, #L_PTE_PRESENT | L_PTE_YOUNG | L_PTE_WRITE | L_PTE_DIRTY + + tst r3, #L_PTE_USER @ User? + orrne r2, r2, #PTE_EXT_AP_URO_SRW @ yes -> user r/o, system r/w + + tst r3, #L_PTE_WRITE | L_PTE_DIRTY @ Write and Dirty? + orreq r2, r2, #PTE_EXT_AP_UNO_SRW @ yes -> user n/a, system r/w + @ combined with user -> user r/w + +#if L2_CACHE_ENABLE + @ If its cacheable it needs to be in L2 also. + eor ip, r1, #L_PTE_CACHEABLE + tst ip, #L_PTE_CACHEABLE + orreq r2, r2, #PTE_EXT_TEX(0x5) +#endif + + tst r3, #L_PTE_PRESENT | L_PTE_YOUNG @ Present and Young? + movne r2, #0 @ no -> fault + + str r2, [r0] @ hardware version + mov ip, #0 + mcr p15, 0, r0, c7, c10, 1 @ Clean D cache line mcr + mcr p15, 0, ip, c7, c10, 4 @ Drain Write Buffer + mov pc, lr + + .ltorg + + .align + + __INIT + + .type __xsc3_setup, #function +__xsc3_setup: + mov r0, #PSR_F_BIT|PSR_I_BIT|SVC_MODE + msr cpsr_c, r0 + mcr p15, 0, ip, c7, c7, 0 @ invalidate I, D caches & BTB + mcr p15, 0, ip, c7, c10, 4 @ Drain Write Buffer + mcr p15, 0, ip, c7, c5, 4 @ Prefetch Flush + mcr p15, 0, ip, c8, c7, 0 @ invalidate I, D TLBs +#if L2_CACHE_ENABLE + orr r4, r4, #0x18 @ cache the page table in L2 +#endif + mcr p15, 0, r4, c2, c0, 0 @ load page table pointer + mov r0, #1 @ Allow access to CP0 and CP13 + orr r0, r0, #1 << 13 @ Its undefined whether this + mcr p15, 0, r0, c15, c1, 0 @ affects USR or SVC modes + mrc p15, 0, r0, c1, c0, 1 @ get auxiliary control reg + and r0, r0, #2 @ preserve bit P bit setting +#if L2_CACHE_ENABLE + orr r0, r0, #(1 << 10) @ enable L2 for LLR cache +#endif + mcr p15, 0, r0, c1, c0, 1 @ set auxiliary control reg + mrc p15, 0, r0, c1, c0, 0 @ get control register + bic r0, r0, #0x0200 @ .... ..R. .... .... + bic r0, r0, #0x0002 @ .... .... .... ..A. + orr r0, r0, #0x0005 @ .... .... .... .C.M +#if BTB_ENABLE + orr r0, r0, #0x3900 @ ..VI Z..S .... .... +#else + orr r0, r0, #0x3100 @ ..VI ...S .... .... +#endif +#if L2_CACHE_ENABLE + orr r0, r0, #0x4000000 @ L2 enable +#endif + mov pc, lr + + .size __xsc3_setup, . - __xsc3_setup + + __INITDATA + +/* + * Purpose : Function pointers used to access above functions - all calls + * come through these + */ + + .type xsc3_processor_functions, #object +ENTRY(xsc3_processor_functions) + .word v5t_early_abort + .word cpu_xsc3_proc_init + .word cpu_xsc3_proc_fin + .word cpu_xsc3_reset + .word cpu_xsc3_do_idle + .word cpu_xsc3_dcache_clean_area + .word cpu_xsc3_switch_mm + .word cpu_xsc3_set_pte + .size xsc3_processor_functions, . - xsc3_processor_functions + + .section ".rodata" + + .type cpu_arch_name, #object +cpu_arch_name: + .asciz "armv5te" + .size cpu_arch_name, . - cpu_arch_name + + .type cpu_elf_name, #object +cpu_elf_name: + .asciz "v5" + .size cpu_elf_name, . - cpu_elf_name + + .type cpu_xsc3_name, #object +cpu_xsc3_name: + .asciz "XScale-Core3" + .size cpu_xsc3_name, . - cpu_xsc3_name + + .align + + .section ".proc.info.init", #alloc, #execinstr + + .type __xsc3_proc_info,#object +__xsc3_proc_info: + .long 0x69056000 + .long 0xffffe000 + .long 0x00000c0e + b __xsc3_setup + .long cpu_arch_name + .long cpu_elf_name + .long HWCAP_SWP|HWCAP_HALF|HWCAP_THUMB|HWCAP_FAST_MULT|HWCAP_EDSP + .long cpu_xsc3_name + .long xsc3_processor_functions + .long v4wbi_tlb_fns + .long xsc3_mc_user_fns + .long xsc3_cache_fns + .size __xsc3_proc_info, . - __xsc3_proc_info |