diff options
Diffstat (limited to 'arch/sh')
| -rw-r--r-- | arch/sh/kernel/cpu/sh5/probe.c | 61 | ||||
| -rw-r--r-- | arch/sh/mm/cache-sh5.c | 1021 |
2 files changed, 439 insertions, 643 deletions
diff --git a/arch/sh/kernel/cpu/sh5/probe.c b/arch/sh/kernel/cpu/sh5/probe.c index 15d167fd0ae7..31f8cb0f6374 100644 --- a/arch/sh/kernel/cpu/sh5/probe.c +++ b/arch/sh/kernel/cpu/sh5/probe.c @@ -20,19 +20,18 @@ int __init detect_cpu_and_cache_system(void) { unsigned long long cir; - /* Do peeks in real mode to avoid having to set up a mapping for the - WPC registers. On SH5-101 cut2, such a mapping would be exposed to - an address translation erratum which would make it hard to set up - correctly. */ + /* + * Do peeks in real mode to avoid having to set up a mapping for + * the WPC registers. On SH5-101 cut2, such a mapping would be + * exposed to an address translation erratum which would make it + * hard to set up correctly. + */ cir = peek_real_address_q(0x0d000008); - if ((cir & 0xffff) == 0x5103) { + if ((cir & 0xffff) == 0x5103) boot_cpu_data.type = CPU_SH5_103; - } else if (((cir >> 32) & 0xffff) == 0x51e2) { + else if (((cir >> 32) & 0xffff) == 0x51e2) /* CPU.VCR aliased at CIR address on SH5-101 */ boot_cpu_data.type = CPU_SH5_101; - } else { - boot_cpu_data.type = CPU_SH_NONE; - } /* * First, setup some sane values for the I-cache. @@ -40,37 +39,33 @@ int __init detect_cpu_and_cache_system(void) boot_cpu_data.icache.ways = 4; boot_cpu_data.icache.sets = 256; boot_cpu_data.icache.linesz = L1_CACHE_BYTES; + boot_cpu_data.icache.way_incr = (1 << 13); + boot_cpu_data.icache.entry_shift = 5; + boot_cpu_data.icache.way_size = boot_cpu_data.icache.sets * + boot_cpu_data.icache.linesz; + boot_cpu_data.icache.entry_mask = 0x1fe0; + boot_cpu_data.icache.flags = 0; -#if 0 /* - * FIXME: This can probably be cleaned up a bit as well.. for example, - * do we really need the way shift _and_ the way_step_shift ?? Judging - * by the existing code, I would guess no.. is there any valid reason - * why we need to be tracking this around? + * Next, setup some sane values for the D-cache. + * + * On the SH5, these are pretty consistent with the I-cache settings, + * so we just copy over the existing definitions.. these can be fixed + * up later, especially if we add runtime CPU probing. + * + * Though in the meantime it saves us from having to duplicate all of + * the above definitions.. */ - boot_cpu_data.icache.way_shift = 13; - boot_cpu_data.icache.entry_shift = 5; - boot_cpu_data.icache.set_shift = 4; - boot_cpu_data.icache.way_step_shift = 16; - boot_cpu_data.icache.asid_shift = 2; + boot_cpu_data.dcache = boot_cpu_data.icache; /* - * way offset = cache size / associativity, so just don't factor in - * associativity in the first place.. + * Setup any cache-related flags here */ - boot_cpu_data.icache.way_ofs = boot_cpu_data.icache.sets * - boot_cpu_data.icache.linesz; - - boot_cpu_data.icache.asid_mask = 0x3fc; - boot_cpu_data.icache.idx_mask = 0x1fe0; - boot_cpu_data.icache.epn_mask = 0xffffe000; +#if defined(CONFIG_CACHE_WRITETHROUGH) + set_bit(SH_CACHE_MODE_WT, &(boot_cpu_data.dcache.flags)); +#elif defined(CONFIG_CACHE_WRITEBACK) + set_bit(SH_CACHE_MODE_WB, &(boot_cpu_data.dcache.flags)); #endif - boot_cpu_data.icache.flags = 0; - - /* A trivial starting point.. */ - memcpy(&boot_cpu_data.dcache, - &boot_cpu_data.icache, sizeof(struct cache_info)); - return 0; } diff --git a/arch/sh/mm/cache-sh5.c b/arch/sh/mm/cache-sh5.c index 5d1f615fe525..3877321fcede 100644 --- a/arch/sh/mm/cache-sh5.c +++ b/arch/sh/mm/cache-sh5.c @@ -1,10 +1,10 @@ /* * arch/sh/mm/cache-sh5.c * - * Original version Copyright (C) 2000, 2001 Paolo Alberelli - * Second version Copyright (C) benedict.gaster@superh.com 2002 - * Third version Copyright Richard.Curnow@superh.com 2003 - * Hacks to third version Copyright (C) 2003 Paul Mundt + * Copyright (C) 2000, 2001 Paolo Alberelli + * Copyright (C) 2002 Benedict Gaster + * Copyright (C) 2003 Richard Curnow + * Copyright (C) 2003 - 2008 Paul Mundt * * This file is subject to the terms and conditions of the GNU General Public * License. See the file "COPYING" in the main directory of this archive @@ -13,101 +13,20 @@ #include <linux/init.h> #include <linux/mman.h> #include <linux/mm.h> -#include <linux/threads.h> -#include <asm/page.h> -#include <asm/pgtable.h> +#include <asm/tlb.h> #include <asm/processor.h> #include <asm/cache.h> -#include <asm/tlb.h> -#include <asm/io.h> +#include <asm/pgalloc.h> #include <asm/uaccess.h> #include <asm/mmu_context.h> -#include <asm/pgalloc.h> /* for flush_itlb_range */ - -#include <linux/proc_fs.h> - -/* This function is in entry.S */ -extern unsigned long switch_and_save_asid(unsigned long new_asid); /* Wired TLB entry for the D-cache */ static unsigned long long dtlb_cache_slot; -/** - * sh64_cache_init() - * - * This is pretty much just a straightforward clone of the SH - * detect_cpu_and_cache_system(). - * - * This function is responsible for setting up all of the cache - * info dynamically as well as taking care of CPU probing and - * setting up the relevant subtype data. - * - * FIXME: For the time being, we only really support the SH5-101 - * out of the box, and don't support dynamic probing for things - * like the SH5-103 or even cut2 of the SH5-101. Implement this - * later! - */ -int __init sh64_cache_init(void) +void __init p3_cache_init(void) { - /* - * First, setup some sane values for the I-cache. - */ - cpu_data->icache.ways = 4; - cpu_data->icache.sets = 256; - cpu_data->icache.linesz = L1_CACHE_BYTES; - - /* - * FIXME: This can probably be cleaned up a bit as well.. for example, - * do we really need the way shift _and_ the way_step_shift ?? Judging - * by the existing code, I would guess no.. is there any valid reason - * why we need to be tracking this around? - */ - cpu_data->icache.way_shift = 13; - cpu_data->icache.entry_shift = 5; - cpu_data->icache.set_shift = 4; - cpu_data->icache.way_step_shift = 16; - cpu_data->icache.asid_shift = 2; - - /* - * way offset = cache size / associativity, so just don't factor in - * associativity in the first place.. - */ - cpu_data->icache.way_ofs = cpu_data->icache.sets * - cpu_data->icache.linesz; - - cpu_data->icache.asid_mask = 0x3fc; - cpu_data->icache.idx_mask = 0x1fe0; - cpu_data->icache.epn_mask = 0xffffe000; - cpu_data->icache.flags = 0; - - /* - * Next, setup some sane values for the D-cache. - * - * On the SH5, these are pretty consistent with the I-cache settings, - * so we just copy over the existing definitions.. these can be fixed - * up later, especially if we add runtime CPU probing. - * - * Though in the meantime it saves us from having to duplicate all of - * the above definitions.. - */ - cpu_data->dcache = cpu_data->icache; - - /* - * Setup any cache-related flags here - */ -#if defined(CONFIG_DCACHE_WRITE_THROUGH) - set_bit(SH_CACHE_MODE_WT, &(cpu_data->dcache.flags)); -#elif defined(CONFIG_DCACHE_WRITE_BACK) - set_bit(SH_CACHE_MODE_WB, &(cpu_data->dcache.flags)); -#endif - - /* - * We also need to reserve a slot for the D-cache in the DTLB, so we - * do this now .. - */ - dtlb_cache_slot = sh64_get_wired_dtlb_entry(); - - return 0; + /* Reserve a slot for dcache colouring in the DTLB */ + dtlb_cache_slot = sh64_get_wired_dtlb_entry(); } #ifdef CONFIG_DCACHE_DISABLED @@ -116,73 +35,48 @@ int __init sh64_cache_init(void) #define sh64_dcache_purge_user_range(mm, start, end) do { } while (0) #define sh64_dcache_purge_phy_page(paddr) do { } while (0) #define sh64_dcache_purge_virt_page(mm, eaddr) do { } while (0) -#define sh64_dcache_purge_kernel_range(start, end) do { } while (0) -#define sh64_dcache_wback_current_user_range(start, end) do { } while (0) #endif -/*##########################################################################*/ - -/* From here onwards, a rewrite of the implementation, - by Richard.Curnow@superh.com. - - The major changes in this compared to the old version are; - 1. use more selective purging through OCBP instead of using ALLOCO to purge - by natural replacement. This avoids purging out unrelated cache lines - that happen to be in the same set. - 2. exploit the APIs copy_user_page and clear_user_page better - 3. be more selective about I-cache purging, in particular use invalidate_all - more sparingly. - - */ - -/*########################################################################## - SUPPORT FUNCTIONS - ##########################################################################*/ - -/****************************************************************************/ -/* The following group of functions deal with mapping and unmapping a temporary - page into the DTLB slot that have been set aside for our exclusive use. */ -/* In order to accomplish this, we use the generic interface for adding and - removing a wired slot entry as defined in arch/sh/mm/tlb-sh5.c */ -/****************************************************************************/ - -static unsigned long slot_own_flags; - -static inline void sh64_setup_dtlb_cache_slot(unsigned long eaddr, unsigned long asid, unsigned long paddr) +/* + * The following group of functions deal with mapping and unmapping a + * temporary page into a DTLB slot that has been set aside for exclusive + * use. + */ +static inline void +sh64_setup_dtlb_cache_slot(unsigned long eaddr, unsigned long asid, + unsigned long paddr) { - local_irq_save(slot_own_flags); + local_irq_disable(); sh64_setup_tlb_slot(dtlb_cache_slot, eaddr, asid, paddr); } static inline void sh64_teardown_dtlb_cache_slot(void) { sh64_teardown_tlb_slot(dtlb_cache_slot); - local_irq_restore(slot_own_flags); + local_irq_enable(); } -/****************************************************************************/ - #ifndef CONFIG_ICACHE_DISABLED - -static void __inline__ sh64_icache_inv_all(void) +static inline void sh64_icache_inv_all(void) { unsigned long long addr, flag, data; unsigned int flags; - addr=ICCR0; - flag=ICCR0_ICI; - data=0; + addr = ICCR0; + flag = ICCR0_ICI; + data = 0; /* Make this a critical section for safety (probably not strictly necessary.) */ local_irq_save(flags); /* Without %1 it gets unexplicably wrong */ - asm volatile("getcfg %3, 0, %0\n\t" - "or %0, %2, %0\n\t" - "putcfg %3, 0, %0\n\t" - "synci" - : "=&r" (data) - : "0" (data), "r" (flag), "r" (addr)); + __asm__ __volatile__ ( + "getcfg %3, 0, %0\n\t" + "or %0, %2, %0\n\t" + "putcfg %3, 0, %0\n\t" + "synci" + : "=&r" (data) + : "0" (data), "r" (flag), "r" (addr)); local_irq_restore(flags); } @@ -193,20 +87,12 @@ static void sh64_icache_inv_kernel_range(unsigned long start, unsigned long end) * the addresses lie in the kernel superpage. */ unsigned long long ullend, addr, aligned_start; -#if (NEFF == 32) aligned_start = (unsigned long long)(signed long long)(signed long) start; -#else -#error "NEFF != 32" -#endif - aligned_start &= L1_CACHE_ALIGN_MASK; - addr = aligned_start; -#if (NEFF == 32) + addr = L1_CACHE_ALIGN(aligned_start); ullend = (unsigned long long) (signed long long) (signed long) end; -#else -#error "NEFF != 32" -#endif + while (addr <= ullend) { - asm __volatile__ ("icbi %0, 0" : : "r" (addr)); + __asm__ __volatile__ ("icbi %0, 0" : : "r" (addr)); addr += L1_CACHE_BYTES; } } @@ -215,7 +101,7 @@ static void sh64_icache_inv_user_page(struct vm_area_struct *vma, unsigned long { /* If we get called, we know that vma->vm_flags contains VM_EXEC. Also, eaddr is page-aligned. */ - + unsigned int cpu = smp_processor_id(); unsigned long long addr, end_addr; unsigned long flags = 0; unsigned long running_asid, vma_asid; @@ -237,17 +123,17 @@ static void sh64_icache_inv_user_page(struct vm_area_struct *vma, unsigned long */ running_asid = get_asid(); - vma_asid = (vma->vm_mm->context & MMU_CONTEXT_ASID_MASK); + vma_asid = cpu_asid(cpu, vma->vm_mm); if (running_asid != vma_asid) { local_irq_save(flags); switch_and_save_asid(vma_asid); } while (addr < end_addr) { /* Worth unrolling a little */ - asm __volatile__("icbi %0, 0" : : "r" (addr)); - asm __volatile__("icbi %0, 32" : : "r" (addr)); - asm __volatile__("icbi %0, 64" : : "r" (addr)); - asm __volatile__("icbi %0, 96" : : "r" (addr)); + __asm__ __volatile__("icbi %0, 0" : : "r" (addr)); + __asm__ __volatile__("icbi %0, 32" : : "r" (addr)); + __asm__ __volatile__("icbi %0, 64" : : "r" (addr)); + __asm__ __volatile__("icbi %0, 96" : : "r" (addr)); addr += 128; } if (running_asid != vma_asid) { @@ -256,8 +142,6 @@ static void sh64_icache_inv_user_page(struct vm_area_struct *vma, unsigned long } } -/****************************************************************************/ - static void sh64_icache_inv_user_page_range(struct mm_struct *mm, unsigned long start, unsigned long end) { @@ -275,10 +159,10 @@ static void sh64_icache_inv_user_page_range(struct mm_struct *mm, possible with the D-cache. Just assume 64 for now as a working figure. */ - int n_pages; - if (!mm) return; + if (!mm) + return; n_pages = ((end - start) >> PAGE_SHIFT); if (n_pages >= 64) { @@ -290,7 +174,7 @@ static void sh64_icache_inv_user_page_range(struct mm_struct *mm, unsigned long mm_asid, current_asid; unsigned long long flags = 0ULL; - mm_asid = mm->context & MMU_CONTEXT_ASID_MASK; + mm_asid = cpu_asid(smp_processor_id(), mm); current_asid = get_asid(); if (mm_asid != current_asid) { @@ -322,6 +206,7 @@ static void sh64_icache_inv_user_page_range(struct mm_struct *mm, } aligned_start = vma->vm_end; /* Skip to start of next region */ } + if (mm_asid != current_asid) { switch_and_save_asid(current_asid); local_irq_restore(flags); @@ -329,47 +214,46 @@ static void sh64_icache_inv_user_page_range(struct mm_struct *mm, } } +/* + * Invalidate a small range of user context I-cache, not necessarily page + * (or even cache-line) aligned. + * + * Since this is used inside ptrace, the ASID in the mm context typically + * won't match current_asid. We'll have to switch ASID to do this. For + * safety, and given that the range will be small, do all this under cli. + * + * Note, there is a hazard that the ASID in mm->context is no longer + * actually associated with mm, i.e. if the mm->context has started a new + * cycle since mm was last active. However, this is just a performance + * issue: all that happens is that we invalidate lines belonging to + * another mm, so the owning process has to refill them when that mm goes + * live again. mm itself can't have any cache entries because there will + * have been a flush_cache_all when the new mm->context cycle started. + */ static void sh64_icache_inv_user_small_range(struct mm_struct *mm, unsigned long start, int len) { - - /* Invalidate a small range of user context I-cache, not necessarily - page (or even cache-line) aligned. */ - unsigned long long eaddr = start; unsigned long long eaddr_end = start + len; unsigned long current_asid, mm_asid; unsigned long long flags; unsigned long long epage_start; - /* Since this is used inside ptrace, the ASID in the mm context - typically won't match current_asid. We'll have to switch ASID to do - this. For safety, and given that the range will be small, do all - this under cli. - - Note, there is a hazard that the ASID in mm->context is no longer - actually associated with mm, i.e. if the mm->context has started a - new cycle since mm was last active. However, this is just a - performance issue: all that happens is that we invalidate lines - belonging to another mm, so the owning process has to refill them - when that mm goes live again. mm itself can't have any cache - entries because there will have been a flush_cache_all when the new - mm->context cycle started. */ - - /* Align to start of cache line. Otherwise, suppose len==8 and start - was at 32N+28 : the last 4 bytes wouldn't get invalidated. */ - eaddr = start & L1_CACHE_ALIGN_MASK; + /* + * Align to start of cache line. Otherwise, suppose len==8 and + * start was at 32N+28 : the last 4 bytes wouldn't get invalidated. + */ + eaddr = L1_CACHE_ALIGN(start); eaddr_end = start + len; + mm_asid = cpu_asid(smp_processor_id(), mm); local_irq_save(flags); - mm_asid = mm->context & MMU_CONTEXT_ASID_MASK; current_asid = switch_and_save_asid(mm_asid); epage_start = eaddr & PAGE_MASK; - while (eaddr < eaddr_end) - { - asm __volatile__("icbi %0, 0" : : "r" (eaddr)); + while (eaddr < eaddr_end) { + __asm__ __volatile__("icbi %0, 0" : : "r" (eaddr)); eaddr += L1_CACHE_BYTES; } switch_and_save_asid(current_asid); @@ -394,30 +278,24 @@ static void sh64_icache_inv_current_user_range(unsigned long start, unsigned lon been recycled since we were last active in which case we might just invalidate another processes I-cache entries : no worries, just a performance drop for him. */ - aligned_start = start & L1_CACHE_ALIGN_MASK; + aligned_start = L1_CACHE_ALIGN(start); addr = aligned_start; while (addr < ull_end) { - asm __volatile__ ("icbi %0, 0" : : "r" (addr)); - asm __volatile__ ("nop"); - asm __volatile__ ("nop"); + __asm__ __volatile__ ("icbi %0, 0" : : "r" (addr)); + __asm__ __volatile__ ("nop"); + __asm__ __volatile__ ("nop"); addr += L1_CACHE_BYTES; } } - #endif /* !CONFIG_ICACHE_DISABLED */ -/****************************************************************************/ - #ifndef CONFIG_DCACHE_DISABLED - /* Buffer used as the target of alloco instructions to purge data from cache sets by natural eviction. -- RPC */ -#define DUMMY_ALLOCO_AREA_SIZE L1_CACHE_SIZE_BYTES + (1024 * 4) +#define DUMMY_ALLOCO_AREA_SIZE ((L1_CACHE_BYTES << 10) + (1024 * 4)) static unsigned char dummy_alloco_area[DUMMY_ALLOCO_AREA_SIZE] __cacheline_aligned = { 0, }; -/****************************************************************************/ - -static void __inline__ sh64_dcache_purge_sets(int sets_to_purge_base, int n_sets) +static void inline sh64_dcache_purge_sets(int sets_to_purge_base, int n_sets) { /* Purge all ways in a particular block of sets, specified by the base set number and number of sets. Can handle wrap-around, if that's @@ -428,102 +306,86 @@ static void __inline__ sh64_dcache_purge_sets(int sets_to_purge_base, int n_sets int j; int set_offset; - dummy_buffer_base_set = ((int)&dummy_alloco_area & cpu_data->dcache.idx_mask) >> cpu_data->dcache.entry_shift; + dummy_buffer_base_set = ((int)&dummy_alloco_area & + cpu_data->dcache.entry_mask) >> + cpu_data->dcache.entry_shift; set_offset = sets_to_purge_base - dummy_buffer_base_set; - for (j=0; j<n_sets; j++, set_offset++) { + for (j = 0; j < n_sets; j++, set_offset++) { set_offset &= (cpu_data->dcache.sets - 1); - eaddr0 = (unsigned long long)dummy_alloco_area + (set_offset << cpu_data->dcache.entry_shift); - - /* Do one alloco which hits the required set per cache way. For - write-back mode, this will purge the #ways resident lines. There's - little point unrolling this loop because the allocos stall more if - they're too close together. */ - eaddr1 = eaddr0 + cpu_data->dcache.way_ofs * cpu_data->dcache.ways; - for (eaddr=eaddr0; eaddr<eaddr1; eaddr+=cpu_data->dcache.way_ofs) { - asm __volatile__ ("alloco %0, 0" : : "r" (eaddr)); - asm __volatile__ ("synco"); /* TAKum03020 */ + eaddr0 = (unsigned long long)dummy_alloco_area + + (set_offset << cpu_data->dcache.entry_shift); + + /* + * Do one alloco which hits the required set per cache + * way. For write-back mode, this will purge the #ways + * resident lines. There's little point unrolling this + * loop because the allocos stall more if they're too + * close together. + */ + eaddr1 = eaddr0 + cpu_data->dcache.way_size * + cpu_data->dcache.ways; + + for (eaddr = eaddr0; eaddr < eaddr1; + eaddr += cpu_data->dcache.way_size) { + __asm__ __volatile__ ("alloco %0, 0" : : "r" (eaddr)); + __asm__ __volatile__ ("synco"); /* TAKum03020 */ } - eaddr1 = eaddr0 + cpu_data->dcache.way_ofs * cpu_data->dcache.ways; - for (eaddr=eaddr0; eaddr<eaddr1; eaddr+=cpu_data->dcache.way_ofs) { - /* Load from each address. Required because alloco is a NOP if - the cache is write-through. Write-through is a config option. */ + eaddr1 = eaddr0 + cpu_data->dcache.way_size * + cpu_data->dcache.ways; + + for (eaddr = eaddr0; eaddr < eaddr1; + eaddr += cpu_data->dcache.way_size) { + /* + * Load from each address. Required because + * alloco is a NOP if the cache is write-through. + */ if (test_bit(SH_CACHE_MODE_WT, &(cpu_data->dcache.flags))) - *(volatile unsigned char *)(int)eaddr; + ctrl_inb(eaddr); } } - /* Don't use OCBI to invalidate the lines. That costs cycles directly. - If the dummy block is just left resident, it will naturally get - evicted as required. */ - - return; + /* + * Don't use OCBI to invalidate the lines. That costs cycles + * directly. If the dummy block is just left resident, it will + * naturally get evicted as required. + */ } -/****************************************************************************/ - +/* + * Purge the entire contents of the dcache. The most efficient way to + * achieve this is to use alloco instructions on a region of unused + * memory equal in size to the cache, thereby causing the current + * contents to be discarded by natural eviction. The alternative, namely + * reading every tag, setting up a mapping for the corresponding page and + * doing an OCBP for the line, would be much more expensive. + */ static void sh64_dcache_purge_all(void) { - /* Purge the entire contents of the dcache. The most efficient way to - achieve this is to use alloco instructions on a region of unused - memory equal in size to the cache, thereby causing the current - contents to be discarded by natural eviction. The alternative, - namely reading every tag, setting up a mapping for the corresponding - page and doing an OCBP for the line, would be much more expensive. - */ sh64_dcache_purge_sets(0, cpu_data->dcache.sets); - - return; - } -/****************************************************************************/ - -static void sh64_dcache_purge_kernel_range(unsigned long start, unsigned long end) -{ - /* Purge the range of addresses [start,end] from the D-cache. The - addresses lie in the superpage mapping. There's no harm if we - overpurge at either end - just a small performance loss. */ - unsigned long long ullend, addr, aligned_start; -#if (NEFF == 32) - aligned_start = (unsigned long long)(signed long long)(signed long) start; -#else -#error "NEFF != 32" -#endif - aligned_start &= L1_CACHE_ALIGN_MASK; - addr = aligned_start; -#if (NEFF == 32) - ullend = (unsigned long long) (signed long long) (signed long) end; -#else -#error "NEFF != 32" -#endif - while (addr <= ullend) { - asm __volatile__ ("ocbp %0, 0" : : "r" (addr)); - addr += L1_CACHE_BYTES; - } - return; -} /* Assumes this address (+ (2**n_synbits) pages up from it) aren't used for anything else in the kernel */ #define MAGIC_PAGE0_START 0xffffffffec000000ULL -static void sh64_dcache_purge_coloured_phy_page(unsigned long paddr, unsigned long eaddr) +/* Purge the physical page 'paddr' from the cache. It's known that any + * cache lines requiring attention have the same page colour as the the + * address 'eaddr'. + * + * This relies on the fact that the D-cache matches on physical tags when + * no virtual tag matches. So we create an alias for the original page + * and purge through that. (Alternatively, we could have done this by + * switching ASID to match the original mapping and purged through that, + * but that involves ASID switching cost + probably a TLBMISS + refill + * anyway.) + */ +static void sh64_dcache_purge_coloured_phy_page(unsigned long paddr, + unsigned long eaddr) { - /* Purge the physical page 'paddr' from the cache. It's known that any - cache lines requiring attention have the same page colour as the the - address 'eaddr'. - - This relies on the fact that the D-cache matches on physical tags - when no virtual tag matches. So we create an alias for the original - page and purge through that. (Alternatively, we could have done - this by switching ASID to match the original mapping and purged - through that, but that involves ASID switching cost + probably a - TLBMISS + refill anyway.) - */ - unsigned long long magic_page_start; unsigned long long magic_eaddr, magic_eaddr_end; @@ -531,47 +393,45 @@ static void sh64_dcache_purge_coloured_phy_page(unsigned long paddr, unsigned lo /* As long as the kernel is not pre-emptible, this doesn't need to be under cli/sti. */ - sh64_setup_dtlb_cache_slot(magic_page_start, get_asid(), paddr); magic_eaddr = magic_page_start; magic_eaddr_end = magic_eaddr + PAGE_SIZE; + while (magic_eaddr < magic_eaddr_end) { /* Little point in unrolling this loop - the OCBPs are blocking and won't go any quicker (i.e. the loop overhead is parallel to part of the OCBP execution.) */ - asm __volatile__ ("ocbp %0, 0" : : "r" (magic_eaddr)); + __asm__ __volatile__ ("ocbp %0, 0" : : "r" (magic_eaddr)); magic_eaddr += L1_CACHE_BYTES; } sh64_teardown_dtlb_cache_slot(); } -/****************************************************************************/ - +/* + * Purge a page given its physical start address, by creating a temporary + * 1 page mapping and purging across that. Even if we know the virtual + * address (& vma or mm) of the page, the method here is more elegant + * because it avoids issues of coping with page faults on the purge + * instructions (i.e. no special-case code required in the critical path + * in the TLB miss handling). + */ static void sh64_dcache_purge_phy_page(unsigned long paddr) { - /* Pure a page given its physical start address, by creating a - temporary 1 page mapping and purging across that. Even if we know - the virtual address (& vma or mm) of the page, the method here is - more elegant because it avoids issues of coping with page faults on - the purge instructions (i.e. no special-case code required in the - critical path in the TLB miss handling). */ - unsigned long long eaddr_start, eaddr, eaddr_end; int i; /* As long as the kernel is not pre-emptible, this doesn't need to be under cli/sti. */ - eaddr_start = MAGIC_PAGE0_START; - for (i=0; i < (1 << CACHE_OC_N_SYNBITS); i++) { + for (i = 0; i < (1 << CACHE_OC_N_SYNBITS); i++) { sh64_setup_dtlb_cache_slot(eaddr_start, get_asid(), paddr); eaddr = eaddr_start; eaddr_end = eaddr + PAGE_SIZE; while (eaddr < eaddr_end) { - asm __volatile__ ("ocbp %0, 0" : : "r" (eaddr)); + __asm__ __volatile__ ("ocbp %0, 0" : : "r" (eaddr)); eaddr += L1_CACHE_BYTES; } @@ -584,6 +444,7 @@ static void sh64_dcache_purge_user_pages(struct mm_struct *mm, unsigned long addr, unsigned long end) { pgd_t *pgd; + pud_t *pud; pmd_t *pmd; pte_t *pte; pte_t entry; @@ -597,7 +458,11 @@ static void sh64_dcache_purge_user_pages(struct mm_struct *mm, if (pgd_bad(*pgd)) return; - pmd = pmd_offset(pgd, addr); + pud = pud_offset(pgd, addr); + if (pud_none(*pud) || pud_bad(*pud)) + return; + + pmd = pmd_offset(pud, addr); if (pmd_none(*pmd) || pmd_bad(*pmd)) return; @@ -611,421 +476,357 @@ static void sh64_dcache_purge_user_pages(struct mm_struct *mm, } while (pte++, addr += PAGE_SIZE, addr != end); pte_unmap_unlock(pte - 1, ptl); } -/****************************************************************************/ +/* + * There are at least 5 choices for the implementation of this, with + * pros (+), cons(-), comments(*): + * + * 1. ocbp each line in the range through the original user's ASID + * + no lines spuriously evicted + * - tlbmiss handling (must either handle faults on demand => extra + * special-case code in tlbmiss critical path), or map the page in + * advance (=> flush_tlb_range in advance to avoid multiple hits) + * - ASID switching + * - expensive for large ranges + * + * 2. temporarily map each page in the range to a special effective + * address and ocbp through the temporary mapping; relies on the + * fact that SH-5 OCB* always do TLB lookup and match on ptags (they + * never look at the etags) + * + no spurious evictions + * - expensive for large ranges + * * surely cheaper than (1) + * + * 3. walk all the lines in the cache, check the tags, if a match + * occurs create a page mapping to ocbp the line through + * + no spurious evictions + * - tag inspection overhead + * - (especially for small ranges) + * - potential cost of setting up/tearing down page mapping for + * every line that matches the range + * * cost partly independent of range size + * + * 4. walk all the lines in the cache, check the tags, if a match + * occurs use 4 * alloco to purge the line (+3 other probably + * innocent victims) by natural eviction + * + no tlb mapping overheads + * - spurious evictions + * - tag inspection overhead + * + * 5. implement like flush_cache_all + * + no tag inspection overhead + * - spurious evictions + * - bad for small ranges + * + * (1) can be ruled out as more expensive than (2). (2) appears best + * for small ranges. The choice between (3), (4) and (5) for large + * ranges and the range size for the large/small boundary need + * benchmarking to determine. + * + * For now use approach (2) for small ranges and (5) for large ones. + */ static void sh64_dcache_purge_user_range(struct mm_struct *mm, unsigned long start, unsigned long end) { - /* There are at least 5 choices for the implementation of this, with - pros (+), cons(-), comments(*): - - 1. ocbp each line in the range through the original user's ASID - + no lines spuriously evicted - - tlbmiss handling (must either handle faults on demand => extra - special-case code in tlbmiss critical path), or map the page in - advance (=> flush_tlb_range in advance to avoid multiple hits) - - ASID switching - - expensive for large ranges - - 2. temporarily map each page in the range to a special effective - address and ocbp through the temporary mapping; relies on the - fact that SH-5 OCB* always do TLB lookup and match on ptags (they - never look at the etags) - + no spurious evictions - - expensive for large ranges - * surely cheaper than (1) - - 3. walk all the lines in the cache, check the tags, if a match - occurs create a page mapping to ocbp the line through - + no spurious evictions - - tag inspection overhead - - (especially for small ranges) - - potential cost of setting up/tearing down page mapping for - every line that matches the range - * cost partly independent of range size - - 4. walk all the lines in the cache, check the tags, if a match - occurs use 4 * alloco to purge the line (+3 other probably - innocent victims) by natural eviction - + no tlb mapping overheads - - spurious evictions - - tag inspection overhead - - 5. implement like flush_cache_all - + no tag inspection overhead - - spurious evictions - - bad for small ranges - - (1) can be ruled out as more expensive than (2). (2) appears best - for small ranges. The choice between (3), (4) and (5) for large - ranges and the range size for the large/small boundary need - benchmarking to determine. - - For now use approach (2) for small ranges and (5) for large ones. - - */ + int n_pages = ((end - start) >> PAGE_SHIFT); - int n_pages; - - n_pages = ((end - start) >> PAGE_SHIFT); if (n_pages >= 64 || ((start ^ (end - 1)) & PMD_MASK)) { -#if 1 sh64_dcache_purge_all(); -#else - unsigned long long set, way; - unsigned long mm_asid = mm->context & MMU_CONTEXT_ASID_MASK; - for (set = 0; set < cpu_data->dcache.sets; set++) { - unsigned long long set_base_config_addr = CACHE_OC_ADDRESS_ARRAY + (set << cpu_data->dcache.set_shift); - for (way = 0; way < cpu_data->dcache.ways; way++) { - unsigned long long config_addr = set_base_config_addr + (way << cpu_data->dcache.way_step_shift); - unsigned long long tag0; - unsigned long line_valid; - - asm __volatile__("getcfg %1, 0, %0" : "=r" (tag0) : "r" (config_addr)); - line_valid = tag0 & SH_CACHE_VALID; - if (line_valid) { - unsigned long cache_asid; - unsigned long epn; - - cache_asid = (tag0 & cpu_data->dcache.asid_mask) >> cpu_data->dcache.asid_shift; - /* The next line needs some - explanation. The virtual tags - encode bits [31:13] of the virtual - address, bit [12] of the 'tag' being - implied by the cache set index. */ - epn = (tag0 & cpu_data->dcache.epn_mask) | ((set & 0x80) << cpu_data->dcache.entry_shift); - - if ((cache_asid == mm_asid) && (start <= epn) && (epn < end)) { - /* TODO : could optimise this - call by batching multiple - adjacent sets together. */ - sh64_dcache_purge_sets(set, 1); - break; /* Don't waste time inspecting other ways for this set */ - } - } - } - } -#endif } else { /* Small range, covered by a single page table page */ start &= PAGE_MASK; /* should already be so */ end = PAGE_ALIGN(end); /* should already be so */ sh64_dcache_purge_user_pages(mm, start, end); } - return; } -static void sh64_dcache_wback_current_user_range(unsigned long start, unsigned long end) +/* + * Purge the range of addresses from the D-cache. + * + * The addresses lie in the superpage mapping. There's no harm if we + * overpurge at either end - just a small performance loss. + */ +void __flush_purge_region(void *start, int size) { - unsigned long long aligned_start; - unsigned long long ull_end; - unsigned long long addr; - - ull_end = end; + unsigned long long ullend, addr, aligned_start; - /* Just wback over the range using the natural addresses. TLB miss - handling will be OK (TBC) : the range has just been written to by - the signal frame setup code, so the PTEs must exist. + aligned_start = (unsigned long long)(signed long long)(signed long) start; + addr = L1_CACHE_ALIGN(aligned_start); + ullend = (unsigned long long) (signed long long) (signed long) start + size; - Note, if we have CONFIG_PREEMPT and get preempted inside this loop, - it doesn't matter, even if the pid->ASID mapping changes whilst - we're away. In that case the cache will have been flushed when the - mapping was renewed. So the writebacks below will be nugatory (and - we'll doubtless have to fault the TLB entry/ies in again with the - new ASID), but it's a rare case. - */ - aligned_start = start & L1_CACHE_ALIGN_MASK; - addr = aligned_start; - while (addr < ull_end) { - asm __volatile__ ("ocbwb %0, 0" : : "r" (addr)); + while (addr <= ullend) { + __asm__ __volatile__ ("ocbp %0, 0" : : "r" (addr)); addr += L1_CACHE_BYTES; } } -/****************************************************************************/ - -/* These *MUST* lie in an area of virtual address space that's otherwise unused. */ -#define UNIQUE_EADDR_START 0xe0000000UL -#define UNIQUE_EADDR_END 0xe8000000UL - -static unsigned long sh64_make_unique_eaddr(unsigned long user_eaddr, unsigned long paddr) +void __flush_wback_region(void *start, int size) { - /* Given a physical address paddr, and a user virtual address - user_eaddr which will eventually be mapped to it, create a one-off - kernel-private eaddr mapped to the same paddr. This is used for - creating special destination pages for copy_user_page and - clear_user_page */ + unsigned long long ullend, addr, aligned_start; - static unsigned long current_pointer = UNIQUE_EADDR_START; - unsigned long coloured_pointer; + aligned_start = (unsigned long long)(signed long long)(signed long) start; + addr = L1_CACHE_ALIGN(aligned_start); + ullend = (unsigned long long) (signed long long) (signed long) start + size; - if (current_pointer == UNIQUE_EADDR_END) { - sh64_dcache_purge_all(); - current_pointer = UNIQUE_EADDR_START; + while (addr < ullend) { + __asm__ __volatile__ ("ocbwb %0, 0" : : "r" (addr)); + addr += L1_CACHE_BYTES; } - - coloured_pointer = (current_pointer & ~CACHE_OC_SYN_MASK) | (user_eaddr & CACHE_OC_SYN_MASK); - sh64_setup_dtlb_cache_slot(coloured_pointer, get_asid(), paddr); - - current_pointer += (PAGE_SIZE << CACHE_OC_N_SYNBITS); - - return coloured_pointer; } -/****************************************************************************/ - -static void sh64_copy_user_page_coloured(void *to, void *from, unsigned long address) +void __flush_invalidate_region(void *start, int size) { - void *coloured_to; - - /* Discard any existing cache entries of the wrong colour. These are - present quite often, if the kernel has recently used the page - internally, then given it up, then it's been allocated to the user. - */ - sh64_dcache_purge_coloured_phy_page(__pa(to), (unsigned long) to); - - coloured_to = (void *) sh64_make_unique_eaddr(address, __pa(to)); - sh64_page_copy(from, coloured_to); - - sh64_teardown_dtlb_cache_slot(); -} - -static void sh64_clear_user_page_coloured(void *to, unsigned long address) -{ - void *coloured_to; - - /* Discard any existing kernel-originated lines of the wrong colour (as - above) */ - sh64_dcache_purge_coloured_phy_page(__pa(to), (unsigned long) to); + unsigned long long ullend, addr, aligned_start; - coloured_to = (void *) sh64_make_unique_eaddr(address, __pa(to)); - sh64_page_clear(coloured_to); + aligned_start = (unsigned long long)(signed long long)(signed long) start; + addr = L1_CACHE_ALIGN(aligned_start); + ullend = (unsigned long long) (signed long long) (signed long) start + size; - sh64_teardown_dtlb_cache_slot(); + while (addr < ullend) { + __asm__ __volatile__ ("ocbi %0, 0" : : "r" (addr)); + addr += L1_CACHE_BYTES; + } } - #endif /* !CONFIG_DCACHE_DISABLED */ -/****************************************************************************/ - -/*########################################################################## - EXTERNALLY CALLABLE API. - ##########################################################################*/ - -/* These functions are described in Documentation/cachetlb.txt. - Each one of these functions varies in behaviour depending on whether the - I-cache and/or D-cache are configured out. - - Note that the Linux term 'flush' corresponds to what is termed 'purge' in - the sh/sh64 jargon for the D-cache, i.e. write back dirty data then - invalidate the cache lines, and 'invalidate' for the I-cache. - */ - -#undef FLUSH_TRACE - +/* + * Invalidate the entire contents of both caches, after writing back to + * memory any dirty data from the D-cache. + */ void flush_cache_all(void) { - /* Invalidate the entire contents of both caches, after writing back to - memory any dirty data from the D-cache. */ sh64_dcache_purge_all(); sh64_icache_inv_all(); } -/****************************************************************************/ - +/* + * Invalidate an entire user-address space from both caches, after + * writing back dirty data (e.g. for shared mmap etc). + * + * This could be coded selectively by inspecting all the tags then + * doing 4*alloco on any set containing a match (as for + * flush_cache_range), but fork/exit/execve (where this is called from) + * are expensive anyway. + * + * Have to do a purge here, despite the comments re I-cache below. + * There could be odd-coloured dirty data associated with the mm still + * in the cache - if this gets written out through natural eviction + * after the kernel has reused the page there will be chaos. + * + * The mm being torn down won't ever be active again, so any Icache + * lines tagged with its ASID won't be visible for the rest of the + * lifetime of this ASID cycle. Before the ASID gets reused, there + * will be a flush_cache_all. Hence we don't need to touch the + * I-cache. This is similar to the lack of action needed in + * flush_tlb_mm - see fault.c. + */ void flush_cache_mm(struct mm_struct *mm) { - /* Invalidate an entire user-address space from both caches, after - writing back dirty data (e.g. for shared mmap etc). */ - - /* This could be coded selectively by inspecting all the tags then - doing 4*alloco on any set containing a match (as for - flush_cache_range), but fork/exit/execve (where this is called from) - are expensive anyway. */ - - /* Have to do a purge here, despite the comments re I-cache below. - There could be odd-coloured dirty data associated with the mm still - in the cache - if this gets written out through natural eviction - after the kernel has reused the page there will be chaos. - */ - sh64_dcache_purge_all(); - - /* The mm being torn down won't ever be active again, so any Icache - lines tagged with its ASID won't be visible for the rest of the - lifetime of this ASID cycle. Before the ASID gets reused, there - will be a flush_cache_all. Hence we don't need to touch the - I-cache. This is similar to the lack of action needed in - flush_tlb_mm - see fault.c. */ } -/****************************************************************************/ - +/* + * Invalidate (from both caches) the range [start,end) of virtual + * addresses from the user address space specified by mm, after writing + * back any dirty data. + * + * Note, 'end' is 1 byte beyond the end of the range to flush. + */ void flush_cache_range(struct vm_area_struct *vma, unsigned long start, unsigned long end) { struct mm_struct *mm = vma->vm_mm; - /* Invalidate (from both caches) the range [start,end) of virtual - addresses from the user address space specified by mm, after writing - back any dirty data. - - Note, 'end' is 1 byte beyond the end of the range to flush. */ - sh64_dcache_purge_user_range(mm, start, end); sh64_icache_inv_user_page_range(mm, start, end); } -/****************************************************************************/ - -void flush_cache_page(struct vm_area_struct *vma, unsigned long eaddr, unsigned long pfn) +/* + * Invalidate any entries in either cache for the vma within the user + * address space vma->vm_mm for the page starting at virtual address + * 'eaddr'. This seems to be used primarily in breaking COW. Note, + * the I-cache must be searched too in case the page in question is + * both writable and being executed from (e.g. stack trampolines.) + * + * Note, this is called with pte lock held. + */ +void flush_cache_page(struct vm_area_struct *vma, unsigned long eaddr, + unsigned long pfn) { - /* Invalidate any entries in either cache for the vma within the user - address space vma->vm_mm for the page starting at virtual address - 'eaddr'. This seems to be used primarily in breaking COW. Note, - the I-cache must be searched too in case the page in question is - both writable and being executed from (e.g. stack trampolines.) - - Note, this is called with pte lock held. - */ - sh64_dcache_purge_phy_page(pfn << PAGE_SHIFT); - if (vma->vm_flags & VM_EXEC) { + if (vma->vm_flags & VM_EXEC) sh64_icache_inv_user_page(vma, eaddr); - } } -/****************************************************************************/ +void flush_dcache_page(struct page *page) +{ + sh64_dcache_purge_phy_page(page_to_phys(page)); + wmb(); +} -#ifndef CONFIG_DCACHE_DISABLED +/* + * Flush the range [start,end] of kernel virtual adddress space from + * the I-cache. The corresponding range must be purged from the + * D-cache also because the SH-5 doesn't have cache snooping between + * the caches. The addresses will be visible through the superpage + * mapping, therefore it's guaranteed that there no cache entries for + * the range in cache sets of the wrong colour. + */ +void flush_icache_range(unsigned long start, unsigned long end) +{ + __flush_purge_region((void *)start, end); + wmb(); + sh64_icache_inv_kernel_range(start, end); +} -void copy_user_page(void *to, void *from, unsigned long address, struct page *page) +/* + * Flush the range of user (defined by vma->vm_mm) address space starting + * at 'addr' for 'len' bytes from the cache. The range does not straddle + * a page boundary, the unique physical page containing the range is + * 'page'. This seems to be used mainly for invalidating an address + * range following a poke into the program text through the ptrace() call + * from another process (e.g. for BRK instruction insertion). + */ +void flush_icache_user_range(struct vm_area_struct *vma, + struct page *page, unsigned long addr, int len) { - /* 'from' and 'to' are kernel virtual addresses (within the superpage - mapping of the physical RAM). 'address' is the user virtual address - where the copy 'to' will be mapped after. This allows a custom - mapping to be used to ensure that the new copy is placed in the - right cache sets for the user to see it without having to bounce it - out via memory. Note however : the call to flush_page_to_ram in - (generic)/mm/memory.c:(break_cow) undoes all this good work in that one - very important case! - - TBD : can we guarantee that on every call, any cache entries for - 'from' are in the same colour sets as 'address' also? i.e. is this - always used just to deal with COW? (I suspect not). */ - - /* There are two possibilities here for when the page 'from' was last accessed: - * by the kernel : this is OK, no purge required. - * by the/a user (e.g. for break_COW) : need to purge. - - If the potential user mapping at 'address' is the same colour as - 'from' there is no need to purge any cache lines from the 'from' - page mapped into cache sets of colour 'address'. (The copy will be - accessing the page through 'from'). - */ - if (((address ^ (unsigned long) from) & CACHE_OC_SYN_MASK) != 0) { - sh64_dcache_purge_coloured_phy_page(__pa(from), address); - } + sh64_dcache_purge_coloured_phy_page(page_to_phys(page), addr); + mb(); - if (((address ^ (unsigned long) to) & CACHE_OC_SYN_MASK) == 0) { - /* No synonym problem on destination */ - sh64_page_copy(from, to); - } else { - sh64_copy_user_page_coloured(to, from, address); - } + if (vma->vm_flags & VM_EXEC) + sh64_icache_inv_user_small_range(vma->vm_mm, addr, len); +} - /* Note, don't need to flush 'from' page from the cache again - it's - done anyway by the generic code */ +/* + * For the address range [start,end), write back the data from the + * D-cache and invalidate the corresponding region of the I-cache for the + * current process. Used to flush signal trampolines on the stack to + * make them executable. + */ +void flush_cache_sigtramp(unsigned long vaddr) +{ + unsigned long end = vaddr + L1_CACHE_BYTES; + + __flush_wback_region((void *)vaddr, L1_CACHE_BYTES); + wmb(); + sh64_icache_inv_current_user_range(vaddr, end); } -void clear_user_page(void *to, unsigned long address, struct page *page) +/* + * These *MUST* lie in an area of virtual address space that's otherwise + * unused. + */ +#define UNIQUE_EADDR_START 0xe0000000UL +#define UNIQUE_EADDR_END 0xe8000000UL + +/* + * Given a physical address paddr, and a user virtual address user_eaddr + * which will eventually be mapped to it, create a one-off kernel-private + * eaddr mapped to the same paddr. This is used for creating special + * destination pages for copy_user_page and clear_user_page. + */ +static unsigned long sh64_make_unique_eaddr(unsigned long user_eaddr, + unsigned long paddr) { - /* 'to' is a kernel virtual address (within the superpage - mapping of the physical RAM). 'address' is the user virtual address - where the 'to' page will be mapped after. This allows a custom - mapping to be used to ensure that the new copy is placed in the - right cache sets for the user to see it without having to bounce it - out via memory. - */ + static unsigned long current_pointer = UNIQUE_EADDR_START; + unsigned long coloured_pointer; - if (((address ^ (unsigned long) to) & CACHE_OC_SYN_MASK) == 0) { - /* No synonym problem on destination */ - sh64_page_clear(to); - } else { - sh64_clear_user_page_coloured(to, address); + if (current_pointer == UNIQUE_EADDR_END) { + sh64_dcache_purge_all(); + current_pointer = UNIQUE_EADDR_START; } -} -#endif /* !CONFIG_DCACHE_DISABLED */ + coloured_pointer = (current_pointer & ~CACHE_OC_SYN_MASK) | + (user_eaddr & CACHE_OC_SYN_MASK); + sh64_setup_dtlb_cache_slot(coloured_pointer, get_asid(), paddr); -/****************************************************************************/ + current_pointer += (PAGE_SIZE << CACHE_OC_N_SYNBITS); -void flush_dcache_page(struct page *page) -{ - sh64_dcache_purge_phy_page(page_to_phys(page)); - wmb(); + return coloured_pointer; } -/****************************************************************************/ - -void flush_icache_range(unsigned long start, unsigned long end) +static void sh64_copy_user_page_coloured(void *to, void *from, + unsigned long address) { - /* Flush the range [start,end] of kernel virtual adddress space from - the I-cache. The corresponding range must be purged from the - D-cache also because the SH-5 doesn't have cache snooping between - the caches. The addresses will be visible through the superpage - mapping, therefore it's guaranteed that there no cache entries for - the range in cache sets of the wrong colour. + void *coloured_to; - Primarily used for cohering the I-cache after a module has - been loaded. */ + /* + * Discard any existing cache entries of the wrong colour. These are + * present quite often, if the kernel has recently used the page + * internally, then given it up, then it's been allocated to the user. + */ + sh64_dcache_purge_coloured_phy_page(__pa(to), (unsigned long)to); - /* We also make sure to purge the same range from the D-cache since - flush_page_to_ram() won't be doing this for us! */ + coloured_to = (void *)sh64_make_unique_eaddr(address, __pa(to)); + copy_page(from, coloured_to); - sh64_dcache_purge_kernel_range(start, end); - wmb(); - sh64_icache_inv_kernel_range(start, end); + sh64_teardown_dtlb_cache_slot(); } -/****************************************************************************/ - -void flush_icache_user_range(struct vm_area_struct *vma, - struct page *page, unsigned long addr, int len) +static void sh64_clear_user_page_coloured(void *to, unsigned long address) { - /* Flush the range of user (defined by vma->vm_mm) address space - starting at 'addr' for 'len' bytes from the cache. The range does - not straddle a page boundary, the unique physical page containing - the range is 'page'. This seems to be used mainly for invalidating - an address range following a poke into the program text through the - ptrace() call from another process (e.g. for BRK instruction - insertion). */ + void *coloured_to; - sh64_dcache_purge_coloured_phy_page(page_to_phys(page), addr); - mb(); + /* + * Discard any existing kernel-originated lines of the wrong + * colour (as above) + */ + sh64_dcache_purge_coloured_phy_page(__pa(to), (unsigned long)to); - if (vma->vm_flags & VM_EXEC) { - sh64_icache_inv_user_small_range(vma->vm_mm, addr, len); - } -} + coloured_to = (void *)sh64_make_unique_eaddr(address, __pa(to)); + clear_page(coloured_to); -/*########################################################################## - ARCH/SH64 PRIVATE CALLABLE API. - ##########################################################################*/ + sh64_teardown_dtlb_cache_slot(); +} -void flush_cache_sigtramp(unsigned long vaddr) +/* + * 'from' and 'to' are kernel virtual addresses (within the superpage + * mapping of the physical RAM). 'address' is the user virtual address + * where the copy 'to' will be mapped after. This allows a custom + * mapping to be used to ensure that the new copy is placed in the + * right cache sets for the user to see it without having to bounce it + * out via memory. Note however : the call to flush_page_to_ram in + * (generic)/mm/memory.c:(break_cow) undoes all this good work in that one + * very important case! + * + * TBD : can we guarantee that on every call, any cache entries for + * 'from' are in the same colour sets as 'address' also? i.e. is this + * always used just to deal with COW? (I suspect not). + * + * There are two possibilities here for when the page 'from' was last accessed: + * - by the kernel : this is OK, no purge required. + * - by the/a user (e.g. for break_COW) : need to purge. + * + * If the potential user mapping at 'address' is the same colour as + * 'from' there is no need to purge any cache lines from the 'from' + * page mapped into cache sets of colour 'address'. (The copy will be + * accessing the page through 'from'). + */ +void copy_user_page(void *to, void *from, unsigned long address, + struct page *page) { - unsigned long end = vaddr + L1_CACHE_BYTES; - - /* For the address range [start,end), write back the data from the - D-cache and invalidate the corresponding region of the I-cache for - the current process. Used to flush signal trampolines on the stack - to make them executable. */ + if (((address ^ (unsigned long) from) & CACHE_OC_SYN_MASK) != 0) + sh64_dcache_purge_coloured_phy_page(__pa(from), address); - sh64_dcache_wback_current_user_range(vaddr, end); - wmb(); - sh64_icache_inv_current_user_range(vaddr, end); + if (((address ^ (unsigned long) to) & CACHE_OC_SYN_MASK) == 0) + copy_page(to, from); + else + sh64_copy_user_page_coloured(to, from, address); } +/* + * 'to' is a kernel virtual address (within the superpage mapping of the + * physical RAM). 'address' is the user virtual address where the 'to' + * page will be mapped after. This allows a custom mapping to be used to + * ensure that the new copy is placed in the right cache sets for the + * user to see it without having to bounce it out via memory. + */ +void clear_user_page(void *to, unsigned long address, struct page *page) +{ + if (((address ^ (unsigned long) to) & CACHE_OC_SYN_MASK) == 0) + clear_page(to); + else + sh64_clear_user_page_coloured(to, address); +} |