Function mmu_change_region_attr() is added to change existing mapping with updated PXN, UXN and memory type. This is a break-before-make process during which the mapping becomes fault (invalid) before final attributres are set.
Signed-off-by: York Sun york.sun@nxp.com ---
Changes in v2: None
arch/arm/cpu/armv8/cache_v8.c | 72 +++++++++++++++++++++++++++++++++++++--- arch/arm/include/asm/armv8/mmu.h | 5 +++ arch/arm/include/asm/system.h | 1 + 3 files changed, 74 insertions(+), 4 deletions(-)
diff --git a/arch/arm/cpu/armv8/cache_v8.c b/arch/arm/cpu/armv8/cache_v8.c index 6c5630c..bd1c3e0 100644 --- a/arch/arm/cpu/armv8/cache_v8.c +++ b/arch/arm/cpu/armv8/cache_v8.c @@ -501,7 +501,8 @@ static bool is_aligned(u64 addr, u64 size, u64 align) return !(addr & (align - 1)) && !(size & (align - 1)); }
-static u64 set_one_region(u64 start, u64 size, u64 attrs, int level) +/* Use flag to indicate if attrs has more than d-cache attributes */ +static u64 set_one_region(u64 start, u64 size, u64 attrs, bool flag, int level) { int levelshift = level2shift(level); u64 levelsize = 1ULL << levelshift; @@ -509,8 +510,13 @@ static u64 set_one_region(u64 start, u64 size, u64 attrs, int level)
/* Can we can just modify the current level block PTE? */ if (is_aligned(start, size, levelsize)) { - *pte &= ~PMD_ATTRINDX_MASK; - *pte |= attrs; + if (flag) { + *pte &= ~PMD_ATTRMASK; + *pte |= attrs & PMD_ATTRMASK; + } else { + *pte &= ~PMD_ATTRINDX_MASK; + *pte |= attrs & PMD_ATTRINDX_MASK; + } debug("Set attrs=%llx pte=%p level=%d\n", attrs, pte, level);
return levelsize; @@ -560,7 +566,8 @@ void mmu_set_region_dcache_behaviour(phys_addr_t start, size_t size, u64 r;
for (level = 1; level < 4; level++) { - r = set_one_region(start, size, attrs, level); + /* Set d-cache attributes only */ + r = set_one_region(start, size, attrs, false, level); if (r) { /* PTE successfully replaced */ size -= r; @@ -581,6 +588,63 @@ void mmu_set_region_dcache_behaviour(phys_addr_t start, size_t size, flush_dcache_range(real_start, real_start + real_size); }
+/* + * Modify MMU table for a region with updated PXN/UXN/Memory type/valid bits. + * The procecess is break-before-make. The target region will be marked as + * invalid during the process of changing. + */ +void mmu_change_region_attr(phys_addr_t addr, size_t siz, u64 attrs) +{ + int level; + u64 r, size, start; + + start = addr; + size = siz; + /* + * Loop through the address range until we find a page granule that fits + * our alignment constraints, then set it to "invalid". + */ + while (size > 0) { + for (level = 1; level < 4; level++) { + /* Set PTE to fault */ + r = set_one_region(start, size, PTE_TYPE_FAULT, true, + level); + if (r) { + /* PTE successfully invalidated */ + size -= r; + start += r; + break; + } + } + } + + flush_dcache_range(gd->arch.tlb_addr, + gd->arch.tlb_addr + gd->arch.tlb_size); + __asm_invalidate_tlb_all(); + + /* + * Loop through the address range until we find a page granule that fits + * our alignment constraints, then set it to the new cache attributes + */ + start = addr; + size = siz; + while (size > 0) { + for (level = 1; level < 4; level++) { + /* Set PTE to new attributes */ + r = set_one_region(start, size, attrs, true, level); + if (r) { + /* PTE successfully updated */ + size -= r; + start += r; + break; + } + } + } + flush_dcache_range(gd->arch.tlb_addr, + gd->arch.tlb_addr + gd->arch.tlb_size); + __asm_invalidate_tlb_all(); +} + #else /* CONFIG_SYS_DCACHE_OFF */
/* diff --git a/arch/arm/include/asm/armv8/mmu.h b/arch/arm/include/asm/armv8/mmu.h index e9b4cdb..a349903 100644 --- a/arch/arm/include/asm/armv8/mmu.h +++ b/arch/arm/include/asm/armv8/mmu.h @@ -53,6 +53,7 @@ #define PTE_TYPE_FAULT (0 << 0) #define PTE_TYPE_TABLE (3 << 0) #define PTE_TYPE_BLOCK (1 << 0) +#define PTE_TYPE_VALID (1 << 0)
#define PTE_TABLE_PXN (1UL << 59) #define PTE_TABLE_XN (1UL << 60) @@ -77,6 +78,10 @@ */ #define PMD_ATTRINDX(t) ((t) << 2) #define PMD_ATTRINDX_MASK (7 << 2) +#define PMD_ATTRMASK (PTE_BLOCK_PXN | \ + PTE_BLOCK_UXN | \ + PMD_ATTRINDX_MASK | \ + PTE_TYPE_VALID)
/* * TCR flags. diff --git a/arch/arm/include/asm/system.h b/arch/arm/include/asm/system.h index 766e929..9c3261c 100644 --- a/arch/arm/include/asm/system.h +++ b/arch/arm/include/asm/system.h @@ -226,6 +226,7 @@ void protect_secure_region(void); void smp_kick_all_cpus(void);
void flush_l3_cache(void); +void mmu_change_region_attr(phys_addr_t start, size_t size, u64 attrs);
/* *Issue a secure monitor call in accordance with ARM "SMC Calling convention",