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Release 4.14 arch/sh/mm/cache-sh4.c

Directory: arch/sh/mm
/*
 * arch/sh/mm/cache-sh4.c
 *
 * Copyright (C) 1999, 2000, 2002  Niibe Yutaka
 * Copyright (C) 2001 - 2009  Paul Mundt
 * Copyright (C) 2003  Richard Curnow
 * Copyright (c) 2007 STMicroelectronics (R&D) Ltd.
 *
 * 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
 * for more details.
 */
#include <linux/init.h>
#include <linux/mm.h>
#include <linux/io.h>
#include <linux/mutex.h>
#include <linux/fs.h>
#include <linux/highmem.h>
#include <asm/pgtable.h>
#include <asm/mmu_context.h>
#include <asm/cache_insns.h>
#include <asm/cacheflush.h>

/*
 * The maximum number of pages we support up to when doing ranged dcache
 * flushing. Anything exceeding this will simply flush the dcache in its
 * entirety.
 */

#define MAX_ICACHE_PAGES	32

static void __flush_cache_one(unsigned long addr, unsigned long phys,
			       unsigned long exec_offset);

/*
 * Write back the range of D-cache, and purge the I-cache.
 *
 * Called from kernel/module.c:sys_init_module and routine for a.out format,
 * signal handler code and kprobes code
 */

static void sh4_flush_icache_range(void *args) { struct flusher_data *data = args; unsigned long start, end; unsigned long flags, v; int i; start = data->addr1; end = data->addr2; /* If there are too many pages then just blow away the caches */ if (((end - start) >> PAGE_SHIFT) >= MAX_ICACHE_PAGES) { local_flush_cache_all(NULL); return; } /* * Selectively flush d-cache then invalidate the i-cache. * This is inefficient, so only use this for small ranges. */ start &= ~(L1_CACHE_BYTES-1); end += L1_CACHE_BYTES-1; end &= ~(L1_CACHE_BYTES-1); local_irq_save(flags); jump_to_uncached(); for (v = start; v < end; v += L1_CACHE_BYTES) { unsigned long icacheaddr; int j, n; __ocbwb(v); icacheaddr = CACHE_IC_ADDRESS_ARRAY | (v & cpu_data->icache.entry_mask); /* Clear i-cache line valid-bit */ n = boot_cpu_data.icache.n_aliases; for (i = 0; i < cpu_data->icache.ways; i++) { for (j = 0; j < n; j++) __raw_writel(0, icacheaddr + (j * PAGE_SIZE)); icacheaddr += cpu_data->icache.way_incr; } } back_to_cached(); local_irq_restore(flags); }

Contributors

PersonTokensPropCommitsCommitProp
Paul Mundt9443.93%541.67%
Christopher SMITH6228.97%18.33%
Matt Fleming3214.95%18.33%
Richard Curnow219.81%18.33%
Linus Torvalds (pre-git)31.40%216.67%
Andrew Morton10.47%18.33%
Stuart Menefy10.47%18.33%
Total214100.00%12100.00%


static inline void flush_cache_one(unsigned long start, unsigned long phys) { unsigned long flags, exec_offset = 0; /* * All types of SH-4 require PC to be uncached to operate on the I-cache. * Some types of SH-4 require PC to be uncached to operate on the D-cache. */ if ((boot_cpu_data.flags & CPU_HAS_P2_FLUSH_BUG) || (start < CACHE_OC_ADDRESS_ARRAY)) exec_offset = cached_to_uncached; local_irq_save(flags); __flush_cache_one(start, phys, exec_offset); local_irq_restore(flags); }

Contributors

PersonTokensPropCommitsCommitProp
Paul Mundt3758.73%650.00%
Linus Torvalds (pre-git)1422.22%216.67%
Andrew Morton812.70%216.67%
Valentin R Sitsikov23.17%18.33%
Matt Fleming23.17%18.33%
Total63100.00%12100.00%

/* * Write back & invalidate the D-cache of the page. * (To avoid "alias" issues) */
static void sh4_flush_dcache_page(void *arg) { struct page *page = arg; unsigned long addr = (unsigned long)page_address(page); #ifndef CONFIG_SMP struct address_space *mapping = page_mapping(page); if (mapping && !mapping_mapped(mapping)) clear_bit(PG_dcache_clean, &page->flags); else #endif flush_cache_one(CACHE_OC_ADDRESS_ARRAY | (addr & shm_align_mask), page_to_phys(page)); wmb(); }

Contributors

PersonTokensPropCommitsCommitProp
Paul Mundt5261.18%861.54%
Matt Fleming2327.06%17.69%
Linus Torvalds44.71%17.69%
Linus Torvalds (pre-git)44.71%17.69%
Valentin R Sitsikov11.18%17.69%
Richard Curnow11.18%17.69%
Total85100.00%13100.00%

/* TODO: Selective icache invalidation through IC address array.. */
static void flush_icache_all(void) { unsigned long flags, ccr; local_irq_save(flags); jump_to_uncached(); /* Flush I-cache */ ccr = __raw_readl(SH_CCR); ccr |= CCR_CACHE_ICI; __raw_writel(ccr, SH_CCR); /* * back_to_cached() will take care of the barrier for us, don't add * another one! */ back_to_cached(); local_irq_restore(flags); }

Contributors

PersonTokensPropCommitsCommitProp
Paul Mundt3366.00%342.86%
Linus Torvalds816.00%114.29%
Linus Torvalds (pre-git)48.00%114.29%
Stuart Menefy36.00%114.29%
Geert Uytterhoeven24.00%114.29%
Total50100.00%7100.00%


static void flush_dcache_all(void) { unsigned long addr, end_addr, entry_offset; end_addr = CACHE_OC_ADDRESS_ARRAY + (current_cpu_data.dcache.sets << current_cpu_data.dcache.entry_shift) * current_cpu_data.dcache.ways; entry_offset = 1 << current_cpu_data.dcache.entry_shift; for (addr = CACHE_OC_ADDRESS_ARRAY; addr < end_addr; ) { __raw_writel(0, addr); addr += entry_offset; __raw_writel(0, addr); addr += entry_offset; __raw_writel(0, addr); addr += entry_offset; __raw_writel(0, addr); addr += entry_offset; __raw_writel(0, addr); addr += entry_offset; __raw_writel(0, addr); addr += entry_offset; __raw_writel(0, addr); addr += entry_offset; __raw_writel(0, addr); addr += entry_offset; } }

Contributors

PersonTokensPropCommitsCommitProp
Paul Mundt15099.34%685.71%
Richard Curnow10.66%114.29%
Total151100.00%7100.00%


static void sh4_flush_cache_all(void *unused) { flush_dcache_all(); flush_icache_all(); }

Contributors

PersonTokensPropCommitsCommitProp
Paul Mundt16100.00%4100.00%
Total16100.00%4100.00%

/* * Note : (RPC) since the caches are physically tagged, the only point * of flush_cache_mm for SH-4 is to get rid of aliases from the * D-cache. The assumption elsewhere, e.g. flush_cache_range, is that * lines can stay resident so long as the virtual address they were * accessed with (hence cache set) is in accord with the physical * address (i.e. tag). It's no different here. * * Caller takes mm->mmap_sem. */
static void sh4_flush_cache_mm(void *arg) { struct mm_struct *mm = arg; if (cpu_context(smp_processor_id(), mm) == NO_CONTEXT) return; flush_dcache_all(); }

Contributors

PersonTokensPropCommitsCommitProp
Paul Mundt3193.94%583.33%
Linus Torvalds26.06%116.67%
Total33100.00%6100.00%

/* * Write back and invalidate I/D-caches for the page. * * ADDR: Virtual Address (U0 address) * PFN: Physical page number */
static void sh4_flush_cache_page(void *args) { struct flusher_data *data = args; struct vm_area_struct *vma; struct page *page; unsigned long address, pfn, phys; int map_coherent = 0; pgd_t *pgd; pud_t *pud; pmd_t *pmd; pte_t *pte; void *vaddr; vma = data->vma; address = data->addr1 & PAGE_MASK; pfn = data->addr2; phys = pfn << PAGE_SHIFT; page = pfn_to_page(pfn); if (cpu_context(smp_processor_id(), vma->vm_mm) == NO_CONTEXT) return; pgd = pgd_offset(vma->vm_mm, address); pud = pud_offset(pgd, address); pmd = pmd_offset(pud, address); pte = pte_offset_kernel(pmd, address); /* If the page isn't present, there is nothing to do here. */ if (!(pte_val(*pte) & _PAGE_PRESENT)) return; if ((vma->vm_mm == current->active_mm)) vaddr = NULL; else { /* * Use kmap_coherent or kmap_atomic to do flushes for * another ASID than the current one. */ map_coherent = (current_cpu_data.dcache.n_aliases && test_bit(PG_dcache_clean, &page->flags) && page_mapcount(page)); if (map_coherent) vaddr = kmap_coherent(page, address); else vaddr = kmap_atomic(page); address = (unsigned long)vaddr; } flush_cache_one(CACHE_OC_ADDRESS_ARRAY | (address & shm_align_mask), phys); if (vma->vm_flags & VM_EXEC) flush_icache_all(); if (vaddr) { if (map_coherent) kunmap_coherent(vaddr); else kunmap_atomic(vaddr); } }

Contributors

PersonTokensPropCommitsCommitProp
Paul Mundt24286.43%960.00%
Linus Torvalds207.14%16.67%
Linus Torvalds (pre-git)82.86%213.33%
Richard Curnow82.86%16.67%
Kirill A. Shutemov10.36%16.67%
Andrew Morton10.36%16.67%
Total280100.00%15100.00%

/* * Write back and invalidate D-caches. * * START, END: Virtual Address (U0 address) * * NOTE: We need to flush the _physical_ page entry. * Flushing the cache lines for U0 only isn't enough. * We need to flush for P1 too, which may contain aliases. */
static void sh4_flush_cache_range(void *args) { struct flusher_data *data = args; struct vm_area_struct *vma; unsigned long start, end; vma = data->vma; start = data->addr1; end = data->addr2; if (cpu_context(smp_processor_id(), vma->vm_mm) == NO_CONTEXT) return; /* * If cache is only 4k-per-way, there are never any 'aliases'. Since * the cache is physically tagged, the data can just be left in there. */ if (boot_cpu_data.dcache.n_aliases == 0) return; flush_dcache_all(); if (vma->vm_flags & VM_EXEC) flush_icache_all(); }

Contributors

PersonTokensPropCommitsCommitProp
Paul Mundt8395.40%787.50%
Richard Curnow44.60%112.50%
Total87100.00%8100.00%

/** * __flush_cache_one * * @addr: address in memory mapped cache array * @phys: P1 address to flush (has to match tags if addr has 'A' bit * set i.e. associative write) * @exec_offset: set to 0x20000000 if flush has to be executed from P2 * region else 0x0 * * The offset into the cache array implied by 'addr' selects the * 'colour' of the virtual address range that will be flushed. The * operation (purge/write-back) is selected by the lower 2 bits of * 'phys'. */
static void __flush_cache_one(unsigned long addr, unsigned long phys, unsigned long exec_offset) { int way_count; unsigned long base_addr = addr; struct cache_info *dcache; unsigned long way_incr; unsigned long a, ea, p; unsigned long temp_pc; dcache = &boot_cpu_data.dcache; /* Write this way for better assembly. */ way_count = dcache->ways; way_incr = dcache->way_incr; /* * Apply exec_offset (i.e. branch to P2 if required.). * * FIXME: * * If I write "=r" for the (temp_pc), it puts this in r6 hence * trashing exec_offset before it's been added on - why? Hence * "=&r" as a 'workaround' */ asm volatile("mov.l 1f, %0\n\t" "add %1, %0\n\t" "jmp @%0\n\t" "nop\n\t" ".balign 4\n\t" "1: .long 2f\n\t" "2:\n" : "=&r" (temp_pc) : "r" (exec_offset)); /* * We know there will be >=1 iteration, so write as do-while to avoid * pointless nead-of-loop check for 0 iterations. */ do { ea = base_addr + PAGE_SIZE; a = base_addr; p = phys; do { *(volatile unsigned long *)a = p; /* * Next line: intentionally not p+32, saves an add, p * will do since only the cache tag bits need to * match. */ *(volatile unsigned long *)(a+32) = p; a += 64; p += 64; } while (a < ea); base_addr += way_incr; } while (--way_count != 0); }

Contributors

PersonTokensPropCommitsCommitProp
Richard Curnow14397.28%125.00%
Paul Mundt42.72%375.00%
Total147100.00%4100.00%

extern void __weak sh4__flush_region_init(void); /* * SH-4 has virtually indexed and physically tagged cache. */
void __init sh4_cache_init(void) { printk("PVR=%08x CVR=%08x PRR=%08x\n", __raw_readl(CCN_PVR), __raw_readl(CCN_CVR), __raw_readl(CCN_PRR)); local_flush_icache_range = sh4_flush_icache_range; local_flush_dcache_page = sh4_flush_dcache_page; local_flush_cache_all = sh4_flush_cache_all; local_flush_cache_mm = sh4_flush_cache_mm; local_flush_cache_dup_mm = sh4_flush_cache_mm; local_flush_cache_page = sh4_flush_cache_page; local_flush_cache_range = sh4_flush_cache_range; sh4__flush_region_init(); }

Contributors

PersonTokensPropCommitsCommitProp
Paul Mundt59100.00%3100.00%
Total59100.00%3100.00%


Overall Contributors

PersonTokensPropCommitsCommitProp
Paul Mundt83966.91%2558.14%
Richard Curnow19015.15%12.33%
Christopher SMITH675.34%12.33%
Matt Fleming574.55%36.98%
Linus Torvalds (pre-git)413.27%511.63%
Linus Torvalds393.11%12.33%
Andrew Morton100.80%36.98%
Stuart Menefy40.32%12.33%
Valentin R Sitsikov40.32%12.33%
Geert Uytterhoeven20.16%12.33%
Kirill A. Shutemov10.08%12.33%
Total1254100.00%43100.00%
Directory: arch/sh/mm
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