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Diffstat (limited to 'src/arch/arm/armv7/mmu.c')
-rw-r--r--src/arch/arm/armv7/mmu.c226
1 files changed, 161 insertions, 65 deletions
diff --git a/src/arch/arm/armv7/mmu.c b/src/arch/arm/armv7/mmu.c
index d71003057a..1b5957c14b 100644
--- a/src/arch/arm/armv7/mmu.c
+++ b/src/arch/arm/armv7/mmu.c
@@ -27,6 +27,7 @@
* SUCH DAMAGE.
*/
+#include <assert.h>
#include <config.h>
#include <stdlib.h>
#include <stdint.h>
@@ -37,32 +38,29 @@
#include <arch/cache.h>
#include <arch/io.h>
-static void *const ttb_buff = (void *)CONFIG_TTB_BUFFER;
-
-void mmu_disable_range(unsigned long start_mb, unsigned long size_mb)
-{
- unsigned int i;
- uint32_t *ttb_entry = ttb_buff;
- printk(BIOS_DEBUG, "Disabling: 0x%08lx:0x%08lx\n",
- start_mb*MiB, start_mb*MiB + size_mb*MiB - 1);
-
- for (i = start_mb; i < start_mb + size_mb; i++)
- writel(0, &ttb_entry[i]);
-
- for (i = start_mb; i < start_mb + size_mb; i++) {
- dccmvac((uintptr_t)&ttb_entry[i]);
- tlbimvaa(i*MiB);
- }
-}
-
-void mmu_config_range(unsigned long start_mb, unsigned long size_mb,
- enum dcache_policy policy)
-{
- unsigned int i;
- uint32_t attr;
- uint32_t *ttb_entry = ttb_buff;
- const char *str = NULL;
-
+#if CONFIG_ARM_LPAE
+/* See B3.6.2 of ARMv7 Architecture Reference Manual */
+/* TODO: Utilize the contiguous hint flag */
+#define ATTR_BASE (\
+ 0ULL << 54 | /* PN. 0:Not restricted */ \
+ 0ULL << 53 | /* PXN. 0:Not restricted */ \
+ 1 << 10 | /* AF. 1:Accessed. This is to prevent access \
+ * fault when accessed for the first time */ \
+ 0 << 6 | /* AP[2:1]. 0b00:full access from PL1 */ \
+ 0 << 5 | /* NS. 0:Output address is in Secure space */ \
+ 0 << 1 | /* block/table. 0:block entry */ \
+ 1 << 0 /* validity. 1:valid */ \
+ )
+#define ATTR_NC (ATTR_BASE | (MAIR_INDX_NC << 2))
+#define ATTR_WT (ATTR_BASE | (MAIR_INDX_WT << 2))
+#define ATTR_WB (ATTR_BASE | (MAIR_INDX_WB << 2))
+
+#define BLOCK_SHIFT 21
+
+typedef uint64_t pgd_t;
+typedef uint64_t pmd_t;
+static const unsigned int denom = 2;
+#else /* CONFIG_ARM_LPAE */
/*
* Section entry bits:
* 31:20 - section base address
@@ -79,19 +77,83 @@ void mmu_config_range(unsigned long start_mb, unsigned long size_mb,
* 2 - B, 1 for bufferable
* 1: 0 - 0b10 to indicate section entry
*/
+#define ATTR_BASE ((3 << 10) | 0x2)
+#define ATTR_NC (ATTR_BASE | (1 << 4))
+#define ATTR_WT (ATTR_BASE | (1 << 3))
+#define ATTR_WB (ATTR_BASE | (1 << 3) | (1 << 2))
+
+#define BLOCK_SHIFT 20
+
+typedef uint32_t pgd_t;
+typedef uint32_t pmd_t;
+static const unsigned int denom = 1;
+#endif /* CONFIG_ARM_LPAE */
+
+static pmd_t *const ttb_buff = (pmd_t *)CONFIG_TTB_BUFFER;
+
+/*
+ * mask/shift/size for pages and blocks
+ */
+#define PAGE_SHIFT 12
+#define PAGE_SIZE (1UL << PAGE_SHIFT)
+#define PAGE_MASK ~((1UL << PAGE_SHIFT) - 1)
+#define BLOCK_SIZE (1UL << BLOCK_SHIFT)
+
+/*
+ * MAIR Index
+ */
+#define MAIR_INDX_NC 0
+#define MAIR_INDX_WT 1
+#define MAIR_INDX_WB 2
+
+static void mmu_flush_page_table_entry_range(
+ unsigned long start_mb, unsigned long size_mb)
+{
+ int i;
+
+ /* Flush the page table entries from the dcache. */
+ for (i = start_mb/denom; i*denom < start_mb + size_mb; i++)
+ dccmvac((uintptr_t)&ttb_buff[i]);
+ dsb();
+ /* Invalidate the TLB entries. */
+ for (i = start_mb/denom; i*denom < start_mb + size_mb; i++)
+ tlbimvaa(i*denom*MiB);
+ dsb();
+ isb();
+}
+
+void mmu_disable_range(unsigned long start_mb, unsigned long size_mb)
+{
+ int i;
+
+ printk(BIOS_DEBUG, "Disabling: [0x%08lx:0x%08lx)\n",
+ start_mb*MiB, start_mb*MiB + size_mb*MiB);
+
+ for (i = start_mb/denom; i*denom < start_mb + size_mb; i++)
+ ttb_buff[i] = 0;
+
+ mmu_flush_page_table_entry_range(start_mb, size_mb);
+}
+
+void mmu_config_range(unsigned long start_mb, unsigned long size_mb,
+ enum dcache_policy policy)
+{
+ const char *str = NULL;
+ pmd_t attr;
+ int i;
switch(policy) {
case DCACHE_OFF:
/* XN set to avoid prefetches to uncached/unbuffered regions */
- attr = (0x3 << 10) | (1 << 4) | 0x2;
+ attr = ATTR_NC;
str = "off";
break;
case DCACHE_WRITEBACK:
- attr = (0x3 << 10) | (1 << 3) | (1 << 2) | 0x2;
+ attr = ATTR_WB;
str = "writeback";
break;
case DCACHE_WRITETHROUGH:
- attr = (0x3 << 10) | (1 << 3) | 0x2;
+ attr = ATTR_WT;
str = "writethrough";
break;
default:
@@ -99,52 +161,86 @@ void mmu_config_range(unsigned long start_mb, unsigned long size_mb,
return;
}
- printk(BIOS_DEBUG, "Setting dcache policy: 0x%08lx:0x%08lx [%s]\n",
- start_mb << 20, ((start_mb + size_mb) << 20) - 1, str);
+ printk(BIOS_DEBUG, "Setting dcache policy: [0x%08lx:0x%08lx) [%s]\n",
+ start_mb << 20, ((start_mb + size_mb) << 20), str);
/* Write out page table entries. */
- for (i = start_mb; i < start_mb + size_mb; i++)
- writel((i << 20) | attr, &ttb_entry[i]);
-
- /* Flush the page table entries from the dcache. */
- for (i = start_mb; i < start_mb + size_mb; i++)
- dccmvac((uintptr_t)&ttb_entry[i]);
+ for (i = start_mb/denom; i*denom < start_mb + size_mb; i++)
+ ttb_buff[i] = ((pmd_t)i << BLOCK_SHIFT) | attr;
- dsb();
-
- /* Invalidate the TLB entries. */
- for (i = start_mb; i < start_mb + size_mb; i++)
- tlbimvaa(i*MiB);
-
- dsb();
- isb();
+ mmu_flush_page_table_entry_range(start_mb, size_mb);
}
+/*
+ * For coreboot's purposes, we will create a simple identity map.
+ *
+ * If LPAE is disabled, we will create a L1 page
+ * table in RAM with 1MB section translation entries over the 4GB address space.
+ * (ref: section 10.2 and example 15-4 in Cortex-A series programmer's guide)
+ *
+ * If LPAE is enabled, we do two level translation with one L1 table with 4
+ * entries, each covering a 1GB space, and four L2 tables with 512 entries, each
+ * covering a 2MB space.
+ */
void mmu_init(void)
{
- /*
- * For coreboot's purposes, we will create a simple L1 page table
- * in RAM with 1MB section translation entries over the 4GB address
- * space.
- * (ref: section 10.2 and example 15-4 in Cortex-A series
- * programmer's guide)
- */
- printk(BIOS_DEBUG, "Translation table is @ %p\n", ttb_buff);
-
- /*
- * Disable TTBR1 by setting TTBCR.N to 0b000, which means the TTBR0
- * table size is 16KB and has indices VA[31:20].
- *
- * ref: Arch Ref. Manual for ARMv7-A, B3.5.4,
- */
- write_ttbcr(read_ttbcr() & ~0x3);
+ if (CONFIG_ARM_LPAE) {
+ pgd_t *const pgd_buff = (pgd_t*)(CONFIG_TTB_BUFFER + 16*KiB);
+ pmd_t *pmd = ttb_buff;
+ int i;
+
+ printk(BIOS_DEBUG, "LPAE Translation tables are @ %p\n",
+ ttb_buff);
+ ASSERT((read_mmfr0() & 0xf) >= 5);
+
+ /*
+ * Set MAIR
+ * See B4.1.104 of ARMv7 Architecture Reference Manual
+ */
+ write_mair0(
+ 0x00 << (MAIR_INDX_NC*8) | /* Strongly-ordered,
+ * Non-Cacheable */
+ 0xaa << (MAIR_INDX_WT*8) | /* Write-Thru,
+ * Read-Allocate */
+ 0xff << (MAIR_INDX_WB*8) /* Write-Back,
+ * Read/Write-Allocate */
+ );
+
+ /*
+ * Set up L1 table
+ * Once set here, L1 table won't be modified by coreboot.
+ * See B3.6.1 of ARMv7 Architecture Reference Manual
+ */
+ for (i = 0; i < 4; i++) {
+ pgd_buff[i] = ((uint32_t)pmd & PAGE_MASK) |
+ 3; /* 0b11: valid table entry */
+ pmd += BLOCK_SIZE / PAGE_SIZE;
+ }
+
+ /*
+ * Set TTBR0
+ */
+ write_ttbr0((uintptr_t)pgd_buff);
+ } else {
+ printk(BIOS_DEBUG, "Translation table is @ %p\n", ttb_buff);
+
+ /*
+ * Translation table base 0 address is in bits 31:14-N, where N
+ * is given by bits 2:0 in TTBCR (which we set to 0). All lower
+ * bits in this register should be zero for coreboot.
+ */
+ write_ttbr0((uintptr_t)ttb_buff);
+ }
/*
- * Translation table base 0 address is in bits 31:14-N, where N is given
- * by bits 2:0 in TTBCR (which we set to 0). All lower bits in this
- * register should be zero for coreboot.
+ * Set TTBCR
+ * See B4.1.153 of ARMv7 Architecture Reference Manual
+ * See B3.5.4 and B3.6.4 for how TTBR0 or TTBR1 is selected.
*/
- write_ttbr0((uintptr_t)ttb_buff);
+ write_ttbcr(
+ CONFIG_ARM_LPAE << 31 | /* EAE. 1:Enable LPAE */
+ 0 << 16 | 0 << 0 /* Use TTBR0 for all addresses */
+ );
/* disable domain-level checking of permissions */
write_dacr(~0);
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