From bb30f36f9b71c31dc8fe3483bba4c9884fc86080 Mon Sep 17 00:00:00 2001 From: Russell King Date: Sat, 6 Sep 2008 20:04:59 +0100 Subject: [PATCH] [ARM] Introduce new PTE memory type bits Provide L_PTE_MT_xxx definitions to describe the memory types that we use in Linux/ARM. These definitions are carefully picked such that: 1. their LSBs match what is required for pre-ARMv6 CPUs. 2. they all have a unique encoding, including after modification by build_mem_type_table() (the result being that some have more than one combination.) Signed-off-by: Russell King --- arch/arm/include/asm/pgtable.h | 33 +++++++++++++++--- arch/arm/mm/copypage-v4mc.c | 2 +- arch/arm/mm/copypage-xscale.c | 2 +- arch/arm/mm/fault-armv.c | 11 +++--- arch/arm/mm/mmu.c | 62 ++++++++++++++++++---------------- 5 files changed, 68 insertions(+), 42 deletions(-) diff --git a/arch/arm/include/asm/pgtable.h b/arch/arm/include/asm/pgtable.h index 5c75e02b3c7..8df2e254a3e 100644 --- a/arch/arm/include/asm/pgtable.h +++ b/arch/arm/include/asm/pgtable.h @@ -164,14 +164,35 @@ extern void __pgd_error(const char *file, int line, unsigned long val); #define L_PTE_PRESENT (1 << 0) #define L_PTE_FILE (1 << 1) /* only when !PRESENT */ #define L_PTE_YOUNG (1 << 1) -#define L_PTE_BUFFERABLE (1 << 2) /* matches PTE */ -#define L_PTE_CACHEABLE (1 << 3) /* matches PTE */ +#define L_PTE_BUFFERABLE (1 << 2) /* obsolete, matches PTE */ +#define L_PTE_CACHEABLE (1 << 3) /* obsolete, matches PTE */ #define L_PTE_DIRTY (1 << 6) #define L_PTE_WRITE (1 << 7) #define L_PTE_USER (1 << 8) #define L_PTE_EXEC (1 << 9) #define L_PTE_SHARED (1 << 10) /* shared(v6), coherent(xsc3) */ +/* + * These are the memory types, defined to be compatible with + * pre-ARMv6 CPUs cacheable and bufferable bits: XXCB + * (note: build_mem_type_table modifies these bits + * to work with our existing proc-*.S setup.) + */ +#define L_PTE_MT_UNCACHED (0x00 << 2) /* 0000 */ +#define L_PTE_MT_BUFFERABLE (0x01 << 2) /* 0001 */ +#define L_PTE_MT_WRITETHROUGH (0x02 << 2) /* 0010 */ +#define L_PTE_MT_WRITEBACK (0x03 << 2) /* 0011 */ +#define L_PTE_MT_MINICACHE (0x06 << 2) /* 0110 (sa1100, xscale) */ +#define L_PTE_MT_WRITEALLOC (0x07 << 2) /* 0111 */ +#define L_PTE_MT_DEV_SHARED (0x04 << 2) /* 0100 (pre-v6) */ +#define L_PTE_MT_DEV_SHARED2 (0x05 << 2) /* 0101 (v6) */ +#define L_PTE_MT_DEV_NONSHARED (0x0c << 2) /* 1100 */ +#define L_PTE_MT_DEV_IXP2000 (0x0d << 2) /* 1101 */ +#define L_PTE_MT_DEV_WC (0x09 << 2) /* 1001 (pre-v6, !xsc3) */ +#define L_PTE_MT_DEV_WC2 (0x08 << 2) /* 1000 (xsc3, v6) */ +#define L_PTE_MT_DEV_CACHED (0x0b << 2) /* 1011 */ +#define L_PTE_MT_MASK (0x0f << 2) + #ifndef __ASSEMBLY__ /* @@ -180,7 +201,7 @@ extern void __pgd_error(const char *file, int line, unsigned long val); * as well as any architecture dependent bits like global/ASID and SMP * shared mapping bits. */ -#define _L_PTE_DEFAULT L_PTE_PRESENT | L_PTE_YOUNG | L_PTE_CACHEABLE | L_PTE_BUFFERABLE +#define _L_PTE_DEFAULT L_PTE_PRESENT | L_PTE_YOUNG #define _L_PTE_READ L_PTE_USER | L_PTE_EXEC extern pgprot_t pgprot_user; @@ -286,8 +307,10 @@ static inline pte_t pte_mkspecial(pte_t pte) { return pte; } /* * Mark the prot value as uncacheable and unbufferable. */ -#define pgprot_noncached(prot) __pgprot(pgprot_val(prot) & ~(L_PTE_CACHEABLE | L_PTE_BUFFERABLE)) -#define pgprot_writecombine(prot) __pgprot(pgprot_val(prot) & ~L_PTE_CACHEABLE) +#define pgprot_noncached(prot) \ + __pgprot((pgprot_val(prot) & ~L_PTE_MT_MASK) | L_PTE_MT_UNCACHED) +#define pgprot_writecombine(prot) \ + __pgprot((pgprot_val(prot) & ~L_PTE_MT_MASK) | L_PTE_MT_BUFFERABLE) #define pmd_none(pmd) (!pmd_val(pmd)) #define pmd_present(pmd) (pmd_val(pmd)) diff --git a/arch/arm/mm/copypage-v4mc.c b/arch/arm/mm/copypage-v4mc.c index ded0e96d069..8d33e254934 100644 --- a/arch/arm/mm/copypage-v4mc.c +++ b/arch/arm/mm/copypage-v4mc.c @@ -28,7 +28,7 @@ * specific hacks for copying pages efficiently. */ #define minicache_pgprot __pgprot(L_PTE_PRESENT | L_PTE_YOUNG | \ - L_PTE_CACHEABLE) + L_PTE_MT_MINICACHE) static DEFINE_SPINLOCK(minicache_lock); diff --git a/arch/arm/mm/copypage-xscale.c b/arch/arm/mm/copypage-xscale.c index 2e455f82a4d..bad49331bbf 100644 --- a/arch/arm/mm/copypage-xscale.c +++ b/arch/arm/mm/copypage-xscale.c @@ -30,7 +30,7 @@ #define COPYPAGE_MINICACHE 0xffff8000 #define minicache_pgprot __pgprot(L_PTE_PRESENT | L_PTE_YOUNG | \ - L_PTE_CACHEABLE) + L_PTE_MT_MINICACHE) static DEFINE_SPINLOCK(minicache_lock); diff --git a/arch/arm/mm/fault-armv.c b/arch/arm/mm/fault-armv.c index a8ec97b4752..6f92904a81e 100644 --- a/arch/arm/mm/fault-armv.c +++ b/arch/arm/mm/fault-armv.c @@ -21,7 +21,7 @@ #include #include -static unsigned long shared_pte_mask = L_PTE_CACHEABLE; +static unsigned long shared_pte_mask = L_PTE_MT_BUFFERABLE; /* * We take the easy way out of this problem - we make the @@ -63,9 +63,10 @@ static int adjust_pte(struct vm_area_struct *vma, unsigned long address) * If this page isn't present, or is already setup to * fault (ie, is old), we can safely ignore any issues. */ - if (ret && pte_val(entry) & shared_pte_mask) { + if (ret && (pte_val(entry) & L_PTE_MT_MASK) != shared_pte_mask) { flush_cache_page(vma, address, pte_pfn(entry)); - pte_val(entry) &= ~shared_pte_mask; + pte_val(entry) &= ~L_PTE_MT_MASK; + pte_val(entry) |= shared_pte_mask; set_pte_at(vma->vm_mm, address, pte, entry); flush_tlb_page(vma, address); } @@ -197,7 +198,7 @@ void __init check_writebuffer_bugs(void) unsigned long *p1, *p2; pgprot_t prot = __pgprot(L_PTE_PRESENT|L_PTE_YOUNG| L_PTE_DIRTY|L_PTE_WRITE| - L_PTE_BUFFERABLE); + L_PTE_MT_BUFFERABLE); p1 = vmap(&page, 1, VM_IOREMAP, prot); p2 = vmap(&page, 1, VM_IOREMAP, prot); @@ -218,7 +219,7 @@ void __init check_writebuffer_bugs(void) if (v) { printk("failed, %s\n", reason); - shared_pte_mask |= L_PTE_BUFFERABLE; + shared_pte_mask = L_PTE_MT_UNCACHED; } else { printk("ok\n"); } diff --git a/arch/arm/mm/mmu.c b/arch/arm/mm/mmu.c index a713e40e1f1..cfc0add4874 100644 --- a/arch/arm/mm/mmu.c +++ b/arch/arm/mm/mmu.c @@ -68,27 +68,27 @@ static struct cachepolicy cache_policies[] __initdata = { .policy = "uncached", .cr_mask = CR_W|CR_C, .pmd = PMD_SECT_UNCACHED, - .pte = 0, + .pte = L_PTE_MT_UNCACHED, }, { .policy = "buffered", .cr_mask = CR_C, .pmd = PMD_SECT_BUFFERED, - .pte = PTE_BUFFERABLE, + .pte = L_PTE_MT_BUFFERABLE, }, { .policy = "writethrough", .cr_mask = 0, .pmd = PMD_SECT_WT, - .pte = PTE_CACHEABLE, + .pte = L_PTE_MT_WRITETHROUGH, }, { .policy = "writeback", .cr_mask = 0, .pmd = PMD_SECT_WB, - .pte = PTE_BUFFERABLE|PTE_CACHEABLE, + .pte = L_PTE_MT_WRITEBACK, }, { .policy = "writealloc", .cr_mask = 0, .pmd = PMD_SECT_WBWA, - .pte = PTE_BUFFERABLE|PTE_CACHEABLE, + .pte = L_PTE_MT_WRITEALLOC, } }; @@ -186,35 +186,36 @@ void adjust_cr(unsigned long mask, unsigned long set) static struct mem_type mem_types[] = { [MT_DEVICE] = { /* Strongly ordered / ARMv6 shared device */ - .prot_pte = PROT_PTE_DEVICE, + .prot_pte = PROT_PTE_DEVICE | L_PTE_MT_DEV_SHARED | + L_PTE_SHARED, .prot_l1 = PMD_TYPE_TABLE, .prot_sect = PROT_SECT_DEVICE | PMD_SECT_UNCACHED, .domain = DOMAIN_IO, }, [MT_DEVICE_NONSHARED] = { /* ARMv6 non-shared device */ - .prot_pte = PROT_PTE_DEVICE, + .prot_pte = PROT_PTE_DEVICE | L_PTE_MT_DEV_NONSHARED, .prot_pte_ext = PTE_EXT_TEX(2), .prot_l1 = PMD_TYPE_TABLE, .prot_sect = PROT_SECT_DEVICE | PMD_SECT_TEX(2), .domain = DOMAIN_IO, }, [MT_DEVICE_CACHED] = { /* ioremap_cached */ - .prot_pte = PROT_PTE_DEVICE | L_PTE_CACHEABLE | L_PTE_BUFFERABLE, + .prot_pte = PROT_PTE_DEVICE | L_PTE_MT_DEV_CACHED, .prot_l1 = PMD_TYPE_TABLE, .prot_sect = PROT_SECT_DEVICE | PMD_SECT_WB, .domain = DOMAIN_IO, }, [MT_DEVICE_IXP2000] = { /* IXP2400 requires XCB=101 for on-chip I/O */ - .prot_pte = PROT_PTE_DEVICE, + .prot_pte = PROT_PTE_DEVICE | L_PTE_MT_DEV_IXP2000, .prot_l1 = PMD_TYPE_TABLE, .prot_sect = PROT_SECT_DEVICE | PMD_SECT_BUFFERABLE | PMD_SECT_TEX(1), .domain = DOMAIN_IO, }, [MT_DEVICE_WC] = { /* ioremap_wc */ - .prot_pte = PROT_PTE_DEVICE, + .prot_pte = PROT_PTE_DEVICE | L_PTE_MT_DEV_WC, .prot_l1 = PMD_TYPE_TABLE, - .prot_sect = PROT_SECT_DEVICE, + .prot_sect = PROT_SECT_DEVICE | PMD_SECT_BUFFERABLE, .domain = DOMAIN_IO, }, [MT_CACHECLEAN] = { @@ -259,7 +260,7 @@ static void __init build_mem_type_table(void) { struct cachepolicy *cp; unsigned int cr = get_cr(); - unsigned int user_pgprot, kern_pgprot; + unsigned int user_pgprot, kern_pgprot, vecs_pgprot; int cpu_arch = cpu_architecture(); int i; @@ -277,6 +278,9 @@ static void __init build_mem_type_table(void) cachepolicy = CPOLICY_WRITEBACK; ecc_mask = 0; } +#ifdef CONFIG_SMP + cachepolicy = CPOLICY_WRITEALLOC; +#endif /* * On non-Xscale3 ARMv5-and-older systems, use CB=01 @@ -286,10 +290,9 @@ static void __init build_mem_type_table(void) */ if (cpu_is_xsc3() || cpu_arch >= CPU_ARCH_ARMv6) { mem_types[MT_DEVICE_WC].prot_pte_ext |= PTE_EXT_TEX(1); + mem_types[MT_DEVICE_WC].prot_pte &= ~L_PTE_BUFFERABLE; mem_types[MT_DEVICE_WC].prot_sect |= PMD_SECT_TEX(1); - } else { - mem_types[MT_DEVICE_WC].prot_pte |= L_PTE_BUFFERABLE; - mem_types[MT_DEVICE_WC].prot_sect |= PMD_SECT_BUFFERABLE; + mem_types[MT_DEVICE_WC].prot_sect &= ~PMD_SECT_BUFFERABLE; } /* @@ -312,7 +315,15 @@ static void __init build_mem_type_table(void) } cp = &cache_policies[cachepolicy]; - kern_pgprot = user_pgprot = cp->pte; + vecs_pgprot = kern_pgprot = user_pgprot = cp->pte; + +#ifndef CONFIG_SMP + /* + * Only use write-through for non-SMP systems + */ + if (cpu_arch >= CPU_ARCH_ARMv5 && cachepolicy > CPOLICY_WRITETHROUGH) + vecs_pgprot = cache_policies[CPOLICY_WRITETHROUGH].pte; +#endif /* * Enable CPU-specific coherency if supported. @@ -349,30 +360,21 @@ static void __init build_mem_type_table(void) */ user_pgprot |= L_PTE_SHARED; kern_pgprot |= L_PTE_SHARED; + vecs_pgprot |= L_PTE_SHARED; mem_types[MT_MEMORY].prot_sect |= PMD_SECT_S; #endif } for (i = 0; i < 16; i++) { unsigned long v = pgprot_val(protection_map[i]); - v = (v & ~(L_PTE_BUFFERABLE|L_PTE_CACHEABLE)) | user_pgprot; - protection_map[i] = __pgprot(v); + protection_map[i] = __pgprot(v | user_pgprot); } - mem_types[MT_LOW_VECTORS].prot_pte |= kern_pgprot; - mem_types[MT_HIGH_VECTORS].prot_pte |= kern_pgprot; + mem_types[MT_LOW_VECTORS].prot_pte |= vecs_pgprot; + mem_types[MT_HIGH_VECTORS].prot_pte |= vecs_pgprot; - if (cpu_arch >= CPU_ARCH_ARMv5) { -#ifndef CONFIG_SMP - /* - * Only use write-through for non-SMP systems - */ - mem_types[MT_LOW_VECTORS].prot_pte &= ~L_PTE_BUFFERABLE; - mem_types[MT_HIGH_VECTORS].prot_pte &= ~L_PTE_BUFFERABLE; -#endif - } else { + if (cpu_arch < CPU_ARCH_ARMv5) mem_types[MT_MINICLEAN].prot_sect &= ~PMD_SECT_TEX(1); - } pgprot_user = __pgprot(L_PTE_PRESENT | L_PTE_YOUNG | user_pgprot); pgprot_kernel = __pgprot(L_PTE_PRESENT | L_PTE_YOUNG | -- 2.41.1