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Diffstat (limited to 'arch/arm/mm/mmu.c')
-rw-r--r--arch/arm/mm/mmu.c70
1 files changed, 70 insertions, 0 deletions
diff --git a/arch/arm/mm/mmu.c b/arch/arm/mm/mmu.c
index 2d6d682c206a..a713e40e1f1a 100644
--- a/arch/arm/mm/mmu.c
+++ b/arch/arm/mm/mmu.c
@@ -211,6 +211,12 @@ static struct mem_type mem_types[] = {
PMD_SECT_TEX(1),
.domain = DOMAIN_IO,
},
+ [MT_DEVICE_WC] = { /* ioremap_wc */
+ .prot_pte = PROT_PTE_DEVICE,
+ .prot_l1 = PMD_TYPE_TABLE,
+ .prot_sect = PROT_SECT_DEVICE,
+ .domain = DOMAIN_IO,
+ },
[MT_CACHECLEAN] = {
.prot_sect = PMD_TYPE_SECT | PMD_SECT_XN,
.domain = DOMAIN_KERNEL,
@@ -273,6 +279,20 @@ static void __init build_mem_type_table(void)
}
/*
+ * On non-Xscale3 ARMv5-and-older systems, use CB=01
+ * (Uncached/Buffered) for ioremap_wc() mappings. On XScale3
+ * and ARMv6+, use TEXCB=00100 mappings (Inner/Outer Uncacheable
+ * in xsc3 parlance, Uncached Normal in ARMv6 parlance).
+ */
+ 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_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;
+ }
+
+ /*
* ARMv5 and lower, bit 4 must be set for page tables.
* (was: cache "update-able on write" bit on ARM610)
* However, Xscale cores require this bit to be cleared.
@@ -568,6 +588,55 @@ void __init iotable_init(struct map_desc *io_desc, int nr)
create_mapping(io_desc + i);
}
+static int __init check_membank_valid(struct membank *mb)
+{
+ /*
+ * Check whether this memory region has non-zero size.
+ */
+ if (mb->size == 0)
+ return 0;
+
+ /*
+ * Check whether this memory region would entirely overlap
+ * the vmalloc area.
+ */
+ if (phys_to_virt(mb->start) >= VMALLOC_MIN) {
+ printk(KERN_NOTICE "Ignoring RAM at %.8lx-%.8lx "
+ "(vmalloc region overlap).\n",
+ mb->start, mb->start + mb->size - 1);
+ return 0;
+ }
+
+ /*
+ * Check whether this memory region would partially overlap
+ * the vmalloc area.
+ */
+ if (phys_to_virt(mb->start + mb->size) < phys_to_virt(mb->start) ||
+ phys_to_virt(mb->start + mb->size) > VMALLOC_MIN) {
+ unsigned long newsize = VMALLOC_MIN - phys_to_virt(mb->start);
+
+ printk(KERN_NOTICE "Truncating RAM at %.8lx-%.8lx "
+ "to -%.8lx (vmalloc region overlap).\n",
+ mb->start, mb->start + mb->size - 1,
+ mb->start + newsize - 1);
+ mb->size = newsize;
+ }
+
+ return 1;
+}
+
+static void __init sanity_check_meminfo(struct meminfo *mi)
+{
+ int i;
+ int j;
+
+ for (i = 0, j = 0; i < mi->nr_banks; i++) {
+ if (check_membank_valid(&mi->bank[i]))
+ mi->bank[j++] = mi->bank[i];
+ }
+ mi->nr_banks = j;
+}
+
static inline void prepare_page_table(struct meminfo *mi)
{
unsigned long addr;
@@ -753,6 +822,7 @@ void __init paging_init(struct meminfo *mi, struct machine_desc *mdesc)
void *zero_page;
build_mem_type_table();
+ sanity_check_meminfo(mi);
prepare_page_table(mi);
bootmem_init(mi);
devicemaps_init(mdesc);