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-rw-r--r--arch/arm/mm/mmu.c238
1 files changed, 104 insertions, 134 deletions
diff --git a/arch/arm/mm/mmu.c b/arch/arm/mm/mmu.c
index b68c6b2..ab14b79 100644
--- a/arch/arm/mm/mmu.c
+++ b/arch/arm/mm/mmu.c
@@ -35,6 +35,7 @@
#include <asm/mach/arch.h>
#include <asm/mach/map.h>
#include <asm/mach/pci.h>
+#include <asm/fixmap.h>
#include "mm.h"
#include "tcm.h"
@@ -117,28 +118,54 @@ static struct cachepolicy cache_policies[] __initdata = {
};
#ifdef CONFIG_CPU_CP15
+static unsigned long initial_pmd_value __initdata = 0;
+
/*
- * These are useful for identifying cache coherency
- * problems by allowing the cache or the cache and
- * writebuffer to be turned off. (Note: the write
- * buffer should not be on and the cache off).
+ * Initialise the cache_policy variable with the initial state specified
+ * via the "pmd" value. This is used to ensure that on ARMv6 and later,
+ * the C code sets the page tables up with the same policy as the head
+ * assembly code, which avoids an illegal state where the TLBs can get
+ * confused. See comments in early_cachepolicy() for more information.
*/
-static int __init early_cachepolicy(char *p)
+void __init init_default_cache_policy(unsigned long pmd)
{
int i;
+ initial_pmd_value = pmd;
+
+ pmd &= PMD_SECT_TEX(1) | PMD_SECT_BUFFERABLE | PMD_SECT_CACHEABLE;
+
+ for (i = 0; i < ARRAY_SIZE(cache_policies); i++)
+ if (cache_policies[i].pmd == pmd) {
+ cachepolicy = i;
+ break;
+ }
+
+ if (i == ARRAY_SIZE(cache_policies))
+ pr_err("ERROR: could not find cache policy\n");
+}
+
+/*
+ * These are useful for identifying cache coherency problems by allowing
+ * the cache or the cache and writebuffer to be turned off. (Note: the
+ * write buffer should not be on and the cache off).
+ */
+static int __init early_cachepolicy(char *p)
+{
+ int i, selected = -1;
+
for (i = 0; i < ARRAY_SIZE(cache_policies); i++) {
int len = strlen(cache_policies[i].policy);
if (memcmp(p, cache_policies[i].policy, len) == 0) {
- cachepolicy = i;
- cr_alignment &= ~cache_policies[i].cr_mask;
- cr_no_alignment &= ~cache_policies[i].cr_mask;
+ selected = i;
break;
}
}
- if (i == ARRAY_SIZE(cache_policies))
- printk(KERN_ERR "ERROR: unknown or unsupported cache policy\n");
+
+ if (selected == -1)
+ pr_err("ERROR: unknown or unsupported cache policy\n");
+
/*
* This restriction is partly to do with the way we boot; it is
* unpredictable to have memory mapped using two different sets of
@@ -146,12 +173,18 @@ static int __init early_cachepolicy(char *p)
* change these attributes once the initial assembly has setup the
* page tables.
*/
- if (cpu_architecture() >= CPU_ARCH_ARMv6) {
- printk(KERN_WARNING "Only cachepolicy=writeback supported on ARMv6 and later\n");
- cachepolicy = CPOLICY_WRITEBACK;
+ if (cpu_architecture() >= CPU_ARCH_ARMv6 && selected != cachepolicy) {
+ pr_warn("Only cachepolicy=%s supported on ARMv6 and later\n",
+ cache_policies[cachepolicy].policy);
+ return 0;
+ }
+
+ if (selected != cachepolicy) {
+ unsigned long cr = __clear_cr(cache_policies[selected].cr_mask);
+ cachepolicy = selected;
+ flush_cache_all();
+ set_cr(cr);
}
- flush_cache_all();
- set_cr(cr_alignment);
return 0;
}
early_param("cachepolicy", early_cachepolicy);
@@ -186,35 +219,6 @@ static int __init early_ecc(char *p)
early_param("ecc", early_ecc);
#endif
-static int __init noalign_setup(char *__unused)
-{
- cr_alignment &= ~CR_A;
- cr_no_alignment &= ~CR_A;
- set_cr(cr_alignment);
- return 1;
-}
-__setup("noalign", noalign_setup);
-
-#ifndef CONFIG_SMP
-void adjust_cr(unsigned long mask, unsigned long set)
-{
- unsigned long flags;
-
- mask &= ~CR_A;
-
- set &= mask;
-
- local_irq_save(flags);
-
- cr_no_alignment = (cr_no_alignment & ~mask) | set;
- cr_alignment = (cr_alignment & ~mask) | set;
-
- set_cr((get_cr() & ~mask) | set);
-
- local_irq_restore(flags);
-}
-#endif
-
#else /* ifdef CONFIG_CPU_CP15 */
static int __init early_cachepolicy(char *p)
@@ -414,8 +418,17 @@ static void __init build_mem_type_table(void)
cachepolicy = CPOLICY_WRITEBACK;
ecc_mask = 0;
}
- if (is_smp())
- cachepolicy = CPOLICY_WRITEALLOC;
+
+ if (is_smp()) {
+ if (cachepolicy != CPOLICY_WRITEALLOC) {
+ pr_warn("Forcing write-allocate cache policy for SMP\n");
+ cachepolicy = CPOLICY_WRITEALLOC;
+ }
+ if (!(initial_pmd_value & PMD_SECT_S)) {
+ pr_warn("Forcing shared mappings for SMP\n");
+ initial_pmd_value |= PMD_SECT_S;
+ }
+ }
/*
* Strip out features not present on earlier architectures.
@@ -539,11 +552,12 @@ static void __init build_mem_type_table(void)
mem_types[MT_CACHECLEAN].prot_sect |= PMD_SECT_APX|PMD_SECT_AP_WRITE;
#endif
- if (is_smp()) {
- /*
- * Mark memory with the "shared" attribute
- * for SMP systems
- */
+ /*
+ * If the initial page tables were created with the S bit
+ * set, then we need to do the same here for the same
+ * reasons given in early_cachepolicy().
+ */
+ if (initial_pmd_value & PMD_SECT_S) {
user_pgprot |= L_PTE_SHARED;
kern_pgprot |= L_PTE_SHARED;
vecs_pgprot |= L_PTE_SHARED;
@@ -1061,74 +1075,47 @@ phys_addr_t arm_lowmem_limit __initdata = 0;
void __init sanity_check_meminfo(void)
{
phys_addr_t memblock_limit = 0;
- int i, j, highmem = 0;
+ int highmem = 0;
phys_addr_t vmalloc_limit = __pa(vmalloc_min - 1) + 1;
+ struct memblock_region *reg;
- for (i = 0, j = 0; i < meminfo.nr_banks; i++) {
- struct membank *bank = &meminfo.bank[j];
- phys_addr_t size_limit;
-
- *bank = meminfo.bank[i];
- size_limit = bank->size;
+ for_each_memblock(memory, reg) {
+ phys_addr_t block_start = reg->base;
+ phys_addr_t block_end = reg->base + reg->size;
+ phys_addr_t size_limit = reg->size;
- if (bank->start >= vmalloc_limit)
+ if (reg->base >= vmalloc_limit)
highmem = 1;
else
- size_limit = vmalloc_limit - bank->start;
+ size_limit = vmalloc_limit - reg->base;
- bank->highmem = highmem;
-#ifdef CONFIG_HIGHMEM
- /*
- * Split those memory banks which are partially overlapping
- * the vmalloc area greatly simplifying things later.
- */
- if (!highmem && bank->size > size_limit) {
- if (meminfo.nr_banks >= NR_BANKS) {
- printk(KERN_CRIT "NR_BANKS too low, "
- "ignoring high memory\n");
- } else {
- memmove(bank + 1, bank,
- (meminfo.nr_banks - i) * sizeof(*bank));
- meminfo.nr_banks++;
- i++;
- bank[1].size -= size_limit;
- bank[1].start = vmalloc_limit;
- bank[1].highmem = highmem = 1;
- j++;
+ if (!IS_ENABLED(CONFIG_HIGHMEM) || cache_is_vipt_aliasing()) {
+
+ if (highmem) {
+ pr_notice("Ignoring RAM at %pa-%pa (!CONFIG_HIGHMEM)\n",
+ &block_start, &block_end);
+ memblock_remove(reg->base, reg->size);
+ continue;
}
- bank->size = size_limit;
- }
-#else
- /*
- * Highmem banks not allowed with !CONFIG_HIGHMEM.
- */
- if (highmem) {
- printk(KERN_NOTICE "Ignoring RAM at %.8llx-%.8llx "
- "(!CONFIG_HIGHMEM).\n",
- (unsigned long long)bank->start,
- (unsigned long long)bank->start + bank->size - 1);
- continue;
- }
- /*
- * Check whether this memory bank would partially overlap
- * the vmalloc area.
- */
- if (bank->size > size_limit) {
- printk(KERN_NOTICE "Truncating RAM at %.8llx-%.8llx "
- "to -%.8llx (vmalloc region overlap).\n",
- (unsigned long long)bank->start,
- (unsigned long long)bank->start + bank->size - 1,
- (unsigned long long)bank->start + size_limit - 1);
- bank->size = size_limit;
+ if (reg->size > size_limit) {
+ phys_addr_t overlap_size = reg->size - size_limit;
+
+ pr_notice("Truncating RAM at %pa-%pa to -%pa",
+ &block_start, &block_end, &vmalloc_limit);
+ memblock_remove(vmalloc_limit, overlap_size);
+ block_end = vmalloc_limit;
+ }
}
-#endif
- if (!bank->highmem) {
- phys_addr_t bank_end = bank->start + bank->size;
- if (bank_end > arm_lowmem_limit)
- arm_lowmem_limit = bank_end;
+ if (!highmem) {
+ if (block_end > arm_lowmem_limit) {
+ if (reg->size > size_limit)
+ arm_lowmem_limit = vmalloc_limit;
+ else
+ arm_lowmem_limit = block_end;
+ }
/*
* Find the first non-section-aligned page, and point
@@ -1144,35 +1131,15 @@ void __init sanity_check_meminfo(void)
* occurs before any free memory is mapped.
*/
if (!memblock_limit) {
- if (!IS_ALIGNED(bank->start, SECTION_SIZE))
- memblock_limit = bank->start;
- else if (!IS_ALIGNED(bank_end, SECTION_SIZE))
- memblock_limit = bank_end;
+ if (!IS_ALIGNED(block_start, SECTION_SIZE))
+ memblock_limit = block_start;
+ else if (!IS_ALIGNED(block_end, SECTION_SIZE))
+ memblock_limit = arm_lowmem_limit;
}
- }
- j++;
- }
-#ifdef CONFIG_HIGHMEM
- if (highmem) {
- const char *reason = NULL;
- if (cache_is_vipt_aliasing()) {
- /*
- * Interactions between kmap and other mappings
- * make highmem support with aliasing VIPT caches
- * rather difficult.
- */
- reason = "with VIPT aliasing cache";
- }
- if (reason) {
- printk(KERN_CRIT "HIGHMEM is not supported %s, ignoring high memory\n",
- reason);
- while (j > 0 && meminfo.bank[j - 1].highmem)
- j--;
}
}
-#endif
- meminfo.nr_banks = j;
+
high_memory = __va(arm_lowmem_limit - 1) + 1;
/*
@@ -1359,6 +1326,9 @@ static void __init kmap_init(void)
#ifdef CONFIG_HIGHMEM
pkmap_page_table = early_pte_alloc(pmd_off_k(PKMAP_BASE),
PKMAP_BASE, _PAGE_KERNEL_TABLE);
+
+ fixmap_page_table = early_pte_alloc(pmd_off_k(FIXADDR_START),
+ FIXADDR_START, _PAGE_KERNEL_TABLE);
#endif
}
@@ -1461,7 +1431,7 @@ void __init early_paging_init(const struct machine_desc *mdesc,
* just complicate the code.
*/
flush_cache_louis();
- dsb();
+ dsb(ishst);
isb();
/* remap level 1 table */
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