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-rw-r--r--src/arch/arm/armv7/mmu.c188
-rw-r--r--src/arch/arm/include/arch/memlayout.h5
-rw-r--r--src/arch/arm/include/armv4/arch/cache.h19
-rw-r--r--src/arch/arm/include/armv7/arch/cache.h11
4 files changed, 136 insertions, 87 deletions
diff --git a/src/arch/arm/armv7/mmu.c b/src/arch/arm/armv7/mmu.c
index e9c681530c..de7fa40f7e 100644
--- a/src/arch/arm/armv7/mmu.c
+++ b/src/arch/arm/armv7/mmu.c
@@ -42,7 +42,7 @@
#if CONFIG_ARM_LPAE
/* See B3.6.2 of ARMv7 Architecture Reference Manual */
/* TODO: Utilize the contiguous hint flag */
-#define ATTR_BASE (\
+#define ATTR_BLOCK (\
0ULL << 54 | /* XN. 0:Not restricted */ \
0ULL << 53 | /* PXN. 0:Not restricted */ \
1 << 10 | /* AF. 1:Accessed. This is to prevent access \
@@ -52,16 +52,18 @@
0 << 1 | /* block/table. 0:block entry */ \
1 << 0 /* validity. 1:valid */ \
)
-#define ATTR_NC (ATTR_BASE | (MAIR_INDX_NC << 2) | \
- (1ULL << 53) | (1ULL << 54))
-#define ATTR_WT (ATTR_BASE | (MAIR_INDX_WT << 2))
-#define ATTR_WB (ATTR_BASE | (MAIR_INDX_WB << 2))
+#define ATTR_PAGE (ATTR_BLOCK | 1 << 1)
+#define ATTR_NEXTLEVEL (0x3)
+#define ATTR_NC ((MAIR_INDX_NC << 2) | (1ULL << 53) | (1ULL << 54))
+#define ATTR_WT (MAIR_INDX_WT << 2)
+#define ATTR_WB (MAIR_INDX_WB << 2)
+#define PAGE_MASK 0x000ffffffffff000ULL
+#define BLOCK_MASK 0x000fffffffe00000ULL
+#define NEXTLEVEL_MASK PAGE_MASK
#define BLOCK_SHIFT 21
-typedef uint64_t pgd_t;
-typedef uint64_t pmd_t;
-static const unsigned int denom = 2;
+typedef uint64_t pte_t;
#else /* CONFIG_ARM_LPAE */
/*
* Section entry bits:
@@ -79,27 +81,28 @@ static const unsigned int denom = 2;
* 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 ATTR_BLOCK ((3 << 10) | 0x2)
+#define ATTR_PAGE ((3 << 4) | 0x2)
+#define ATTR_NEXTLEVEL (0x1)
+#define ATTR_NC (1 << 4)
+#define ATTR_WT (1 << 3)
+#define ATTR_WB ((1 << 3) | (1 << 2))
+#define PAGE_MASK 0xfffff000UL
+#define BLOCK_MASK 0xfff00000UL
+#define NEXTLEVEL_MASK 0xfffffc00UL
#define BLOCK_SHIFT 20
-typedef uint32_t pgd_t;
-typedef uint32_t pmd_t;
-static const unsigned int denom = 1;
+typedef uint32_t pte_t;
#endif /* CONFIG_ARM_LPAE */
-static pmd_t *const ttb_buff = (pmd_t *)_ttb;
-
/*
* 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)
+#define SUBTABLE_SIZE ((1 << (BLOCK_SHIFT - PAGE_SHIFT)) * sizeof(pte_t))
/*
* MAIR Index
@@ -108,69 +111,124 @@ static pmd_t *const ttb_buff = (pmd_t *)_ttb;
#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)
+static pte_t *const ttb_buff = (void *)_ttb;
+static int used_tables = 0;
+
+/* Not all boards want to use subtables and declare them in memlayout.ld. This
+ * outputs two 0x00000000 symbols if they don't, making _ttb_subtables_size 0.
+ * (I would like to explicitly assign them to 0 here, but that triggers
+ * https://sourceware.org/bugzilla/show_bug.cgi?id=1038 in GNU as.) */
+asm (".weak _ttb_subtables, _ettb_subtables");
+
+static struct {
+ pte_t value;
+ const char *name;
+} attrs[] = {
+ [DCACHE_OFF] = {.value = ATTR_NC, .name = "uncached"},
+ [DCACHE_WRITEBACK] = {.value = ATTR_WB, .name = "writeback"},
+ [DCACHE_WRITETHROUGH] = {.value = ATTR_WT, .name = "writethrough"},
+};
+
+/* Fills page table entries in |table| from |start_idx| to |end_idx| with |attr|
+ * and performs necessary invalidations. |offset| is the start address of the
+ * area described by |table|, and |shift| is the size-shift of each frame. */
+static void mmu_fill_table(pte_t *table, u32 start_idx, u32 end_idx,
+ uintptr_t offset, u32 shift, pte_t attr)
{
int i;
+ /* Write out page table entries. */
+ for (i = start_idx; i < end_idx; i++)
+ table[i] = (offset + (i << shift)) | attr;
+
/* 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]);
+ for (i = start_idx; i < end_idx; i++)
+ dccmvac((uintptr_t)&table[i]);
dsb();
+
/* Invalidate the TLB entries. */
- for (i = start_mb/denom; i*denom < start_mb + size_mb; i++)
- tlbimvaa(i*denom*MiB);
+ for (i = start_idx; i < end_idx; i++)
+ tlbimvaa(offset + (i << shift));
dsb();
isb();
}
-void mmu_disable_range(unsigned long start_mb, unsigned long size_mb)
+static pte_t *mmu_create_subtable(pte_t *pgd_entry)
{
- int i;
+ if (used_tables >= _ttb_subtables_size / SUBTABLE_SIZE)
+ die("Not enough room for another sub-pagetable!");
- printk(BIOS_DEBUG, "Disabling: [0x%08lx:0x%08lx)\n",
- start_mb*MiB, start_mb*MiB + size_mb*MiB);
+ /* We assume that *pgd_entry must already be a valid block mapping. */
+ uintptr_t start_addr = (uintptr_t)(*pgd_entry & BLOCK_MASK);
+ pte_t *table = (void *)(_ttb_subtables + used_tables++ * SUBTABLE_SIZE);
+ printk(BIOS_DEBUG, "Creating new subtable @%p for [%#.8x:%#.8lx)\n",
+ table, start_addr, start_addr + BLOCK_SIZE);
- for (i = start_mb/denom; i*denom < start_mb + size_mb; i++)
- ttb_buff[i] = 0;
+ /* Initialize the new subtable with entries of the same attributes
+ * (XN bit moves from 4 to 0, set PAGE unless block was unmapped). */
+ pte_t attr = *pgd_entry & ~(BLOCK_MASK);
+ if (!IS_ENABLED(CONFIG_ARM_LPAE) && (attr & (1 << 4)))
+ attr = ((attr & ~(1 << 4)) | (1 << 0));
+ if (attr & ATTR_BLOCK)
+ attr = (attr & ~ATTR_BLOCK) | ATTR_PAGE;
+ mmu_fill_table(table, 0, SUBTABLE_SIZE / sizeof(pte_t),
+ start_addr, PAGE_SHIFT, attr);
- mmu_flush_page_table_entry_range(start_mb, size_mb);
+ /* Replace old entry in upper level table to point at subtable. */
+ *pgd_entry = (pte_t)(uintptr_t)table | ATTR_NEXTLEVEL;
+ dccmvac((uintptr_t)pgd_entry);
+ dsb();
+ tlbimvaa(start_addr);
+ dsb();
+ isb();
+
+ return table;
}
-void mmu_config_range(unsigned long start_mb, unsigned long size_mb,
- enum dcache_policy policy)
+void mmu_config_range_kb(u32 start_kb, u32 size_kb, enum dcache_policy policy)
{
- const char *str = NULL;
- pmd_t attr;
- int i;
+ pte_t *pgd_entry = &ttb_buff[start_kb / (BLOCK_SIZE/KiB)];
+ pte_t *table = (void *)(uintptr_t)(*pgd_entry & NEXTLEVEL_MASK);
- switch(policy) {
- case DCACHE_OFF:
- /* XN set to avoid prefetches to uncached/unbuffered regions */
- attr = ATTR_NC;
- str = "off";
- break;
- case DCACHE_WRITEBACK:
- attr = ATTR_WB;
- str = "writeback";
- break;
- case DCACHE_WRITETHROUGH:
- attr = ATTR_WT;
- str = "writethrough";
- break;
- default:
- printk(BIOS_ERR, "unknown dcache policy: %02x\n", policy);
- return;
- }
-
- printk(BIOS_DEBUG, "Setting dcache policy: [0x%08lx:0x%08lx) [%s]\n",
- start_mb << 20, ((start_mb + size_mb) << 20), str);
+ /* Make sure the range is contained within a single superpage. */
+ assert(((start_kb + size_kb - 1) & (BLOCK_MASK/KiB))
+ == (start_kb & (BLOCK_MASK/KiB)) && start_kb < 4 * (GiB/KiB));
- /* Write out page table entries. */
- for (i = start_mb/denom; i*denom < start_mb + size_mb; i++)
- ttb_buff[i] = ((pmd_t)i << BLOCK_SHIFT) | attr;
+ if ((*pgd_entry & ~NEXTLEVEL_MASK) != ATTR_NEXTLEVEL)
+ table = mmu_create_subtable(pgd_entry);
+
+ /* Always _one_ _damn_ bit that won't fit... (XN moves from 4 to 0) */
+ pte_t attr = attrs[policy].value;
+ if (!IS_ENABLED(CONFIG_ARM_LPAE) && (attr & (1 << 4)))
+ attr = ((attr & ~(1 << 4)) | (1 << 0));
+
+ /* Mask away high address bits that are handled by upper level table. */
+ u32 mask = BLOCK_SIZE/KiB - 1;
+ printk(BIOS_DEBUG, "Mapping address range [%#.8x:%#.8x) as %s\n",
+ start_kb * KiB, (start_kb + size_kb) * KiB, attrs[policy].name);
+ mmu_fill_table(table, (start_kb & mask) / (PAGE_SIZE/KiB),
+ div_round_up((start_kb + size_kb) & mask, PAGE_SIZE/KiB),
+ (start_kb & ~mask) * KiB, PAGE_SHIFT, ATTR_PAGE | attr);
+}
- mmu_flush_page_table_entry_range(start_mb, size_mb);
+void mmu_disable_range(u32 start_mb, u32 size_mb)
+{
+ printk(BIOS_DEBUG, "Setting address range [%#.8x:%#.8x) as unmapped\n",
+ start_mb * MiB, (start_mb + size_mb) * MiB);
+ assert(start_mb + size_mb <= 4 * (GiB/MiB));
+ mmu_fill_table(ttb_buff, start_mb / (BLOCK_SIZE/MiB),
+ div_round_up(start_mb + size_mb, BLOCK_SIZE/MiB),
+ 0, BLOCK_SHIFT, 0);
+}
+
+void mmu_config_range(u32 start_mb, u32 size_mb, enum dcache_policy policy)
+{
+ printk(BIOS_DEBUG, "Mapping address range [%#.8x:%#.8x) as %s\n",
+ start_mb * MiB, (start_mb + size_mb) * MiB, attrs[policy].name);
+ assert(start_mb + size_mb <= 4 * (GiB/MiB));
+ mmu_fill_table(ttb_buff, start_mb / (BLOCK_SIZE/MiB),
+ div_round_up(start_mb + size_mb, BLOCK_SIZE/MiB),
+ 0, BLOCK_SHIFT, ATTR_BLOCK | attrs[policy].value);
}
/*
@@ -187,8 +245,8 @@ void mmu_config_range(unsigned long start_mb, unsigned long size_mb,
void mmu_init(void)
{
if (CONFIG_ARM_LPAE) {
- pgd_t *const pgd_buff = (pgd_t*)(_ttb + 16*KiB);
- pmd_t *pmd = ttb_buff;
+ pte_t *const pgd_buff = (pte_t*)(_ttb + 16*KiB);
+ pte_t *pmd = ttb_buff;
int i;
printk(BIOS_DEBUG, "LPAE Translation tables are @ %p\n",
@@ -214,8 +272,8 @@ void mmu_init(void)
* 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 */
+ pgd_buff[i] = ((uint32_t)pmd & NEXTLEVEL_MASK) |
+ ATTR_NEXTLEVEL;
pmd += BLOCK_SIZE / PAGE_SIZE;
}
diff --git a/src/arch/arm/include/arch/memlayout.h b/src/arch/arm/include/arch/memlayout.h
index 9f5b383160..2c733946a2 100644
--- a/src/arch/arm/include/arch/memlayout.h
+++ b/src/arch/arm/include/arch/memlayout.h
@@ -27,6 +27,11 @@
_ = ASSERT(size >= 16K + IS_ENABLED(CONFIG_ARM_LPAE) * 32, \
"TTB must be 16K (+ 32 for LPAE)!");
+#define TTB_SUBTABLES(addr, size) \
+ REGION(ttb_subtables, addr, size, IS_ENABLED(CONFIG_ARM_LPAE)*3K + 1K) \
+ _ = ASSERT(size % (1K + 3K * IS_ENABLED(CONFIG_ARM_LPAE)) == 0, \
+ "TTB subtable region must be evenly divisible by table size!");
+
/* ARM stacks need 8-byte alignment and stay in one place through ramstage. */
#define STACK(addr, size) REGION(stack, addr, size, 8)
diff --git a/src/arch/arm/include/armv4/arch/cache.h b/src/arch/arm/include/armv4/arch/cache.h
index e41ff9a49f..65f59662a6 100644
--- a/src/arch/arm/include/armv4/arch/cache.h
+++ b/src/arch/arm/include/armv4/arch/cache.h
@@ -72,23 +72,4 @@ void cache_sync_instructions(void);
/* tlb invalidate all */
void tlb_invalidate_all(void);
-/*
- * Generalized setup/init functions
- */
-
-/* mmu initialization (set page table address, set permissions, etc) */
-void mmu_init(void);
-
-enum dcache_policy {
- DCACHE_OFF,
- DCACHE_WRITEBACK,
- DCACHE_WRITETHROUGH,
-};
-
-/* disable the mmu for a range. Primarily useful to lock out address 0. */
-void mmu_disable_range(unsigned long start_mb, unsigned long size_mb);
-/* mmu range configuration (set dcache policy) */
-void mmu_config_range(unsigned long start_mb, unsigned long size_mb,
- enum dcache_policy policy);
-
#endif /* ARM_CACHE_H */
diff --git a/src/arch/arm/include/armv7/arch/cache.h b/src/arch/arm/include/armv7/arch/cache.h
index dde2c08c1d..f23dec1bbb 100644
--- a/src/arch/arm/include/armv7/arch/cache.h
+++ b/src/arch/arm/include/armv7/arch/cache.h
@@ -345,9 +345,14 @@ enum dcache_policy {
};
/* disable the mmu for a range. Primarily useful to lock out address 0. */
-void mmu_disable_range(unsigned long start_mb, unsigned long size_mb);
+void mmu_disable_range(u32 start_mb, u32 size_mb);
/* mmu range configuration (set dcache policy) */
-void mmu_config_range(unsigned long start_mb, unsigned long size_mb,
- enum dcache_policy policy);
+void mmu_config_range(u32 start_mb, u32 size_mb, enum dcache_policy policy);
+
+/* Reconfigure memory mappings at the fine-grained (4K) page level. Must be
+ * called on a range contained within a single, already mapped block/superpage.
+ * Careful: Do NOT map over this address range with mmu_config_range() again
+ * later, or you will leak resources and may desync your TLB! */
+void mmu_config_range_kb(u32 start_kb, u32 size_kb, enum dcache_policy policy);
#endif /* ARM_CACHE_H */
generated by cgit v1.2.3 (git 2.25.1) at 2024-11-22 18:31:25 +0000