1 files changed, 104 insertions, 134 deletions

diff --git a/arch/arm/mm/mmu.c b/arch/arm/mm/mmu.c
index b68c6b22e1c8..ab14b79b03f0 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 */