diff options
Diffstat (limited to 'arch/arm/mm/pmsa-v7.c')
| -rw-r--r-- | arch/arm/mm/pmsa-v7.c | 70 |
1 files changed, 51 insertions, 19 deletions
diff --git a/arch/arm/mm/pmsa-v7.c b/arch/arm/mm/pmsa-v7.c index 484f5aa51090..cd798271a78d 100644 --- a/arch/arm/mm/pmsa-v7.c +++ b/arch/arm/mm/pmsa-v7.c @@ -12,6 +12,9 @@ #include "mm.h" +static unsigned int __initdata mpu_min_region_order; +static unsigned int __initdata mpu_max_regions; + #define DRBAR __ACCESS_CP15(c6, 0, c1, 0) #define IRBAR __ACCESS_CP15(c6, 0, c1, 1) #define DRSR __ACCESS_CP15(c6, 0, c1, 2) @@ -75,6 +78,11 @@ static inline u32 irbar_read(void) return read_sysreg(IRBAR); } +static int __init mpu_present(void) +{ + return ((read_cpuid_ext(CPUID_EXT_MMFR0) & MMFR0_PMSA) == MMFR0_PMSAv7); +} + /* MPU initialisation functions */ void __init adjust_lowmem_bounds_mpu(void) { @@ -85,6 +93,9 @@ void __init adjust_lowmem_bounds_mpu(void) phys_addr_t mem_start; phys_addr_t mem_end; + if (!mpu_present()) + return; + for_each_memblock(memory, reg) { if (first) { /* @@ -146,12 +157,7 @@ void __init adjust_lowmem_bounds_mpu(void) } -static int mpu_present(void) -{ - return ((read_cpuid_ext(CPUID_EXT_MMFR0) & MMFR0_PMSA) == MMFR0_PMSAv7); -} - -static int mpu_max_regions(void) +static int __init __mpu_max_regions(void) { /* * We don't support a different number of I/D side regions so if we @@ -159,6 +165,7 @@ static int mpu_max_regions(void) * whichever side has a smaller number of supported regions. */ u32 dregions, iregions, mpuir; + mpuir = read_cpuid(CPUID_MPUIR); dregions = iregions = (mpuir & MPUIR_DREGION_SZMASK) >> MPUIR_DREGION; @@ -171,15 +178,16 @@ static int mpu_max_regions(void) return min(dregions, iregions); } -static int mpu_iside_independent(void) +static int __init mpu_iside_independent(void) { /* MPUIR.nU specifies whether there is *not* a unified memory map */ return read_cpuid(CPUID_MPUIR) & MPUIR_nU; } -static int mpu_min_region_order(void) +static int __init __mpu_min_region_order(void) { u32 drbar_result, irbar_result; + /* We've kept a region free for this probing */ rgnr_write(MPU_PROBE_REGION); isb(); @@ -198,22 +206,24 @@ static int mpu_min_region_order(void) } isb(); /* Ensure that MPU region operations have completed */ /* Return whichever result is larger */ + return __ffs(max(drbar_result, irbar_result)); } -static int mpu_setup_region(unsigned int number, phys_addr_t start, +static int __init mpu_setup_region(unsigned int number, phys_addr_t start, unsigned int size_order, unsigned int properties) { u32 size_data; /* We kept a region free for probing resolution of MPU regions*/ - if (number > mpu_max_regions() || number == MPU_PROBE_REGION) + if (number > mpu_max_regions + || number >= MPU_MAX_REGIONS) return -ENOENT; if (size_order > 32) return -ENOMEM; - if (size_order < mpu_min_region_order()) + if (size_order < mpu_min_region_order) return -ENOMEM; /* Writing N to bits 5:1 (RSR_SZ) specifies region size 2^N+1 */ @@ -240,6 +250,9 @@ static int mpu_setup_region(unsigned int number, phys_addr_t start, mpu_rgn_info.rgns[number].dracr = properties; mpu_rgn_info.rgns[number].drbar = start; mpu_rgn_info.rgns[number].drsr = size_data; + + mpu_rgn_info.used++; + return 0; } @@ -248,19 +261,38 @@ static int mpu_setup_region(unsigned int number, phys_addr_t start, */ void __init mpu_setup(void) { - int region_err; + int region = 0, err = 0; + if (!mpu_present()) return; - region_err = mpu_setup_region(MPU_RAM_REGION, PHYS_OFFSET, - ilog2(memblock.memory.regions[0].size), - MPU_AP_PL1RW_PL0RW | MPU_RGN_NORMAL); - if (region_err) { - panic("MPU region initialization failure! %d", region_err); + /* Free-up MPU_PROBE_REGION */ + mpu_min_region_order = __mpu_min_region_order(); + + /* How many regions are supported */ + mpu_max_regions = __mpu_max_regions(); + + /* Now setup MPU (order is important) */ + + /* Background */ + err |= mpu_setup_region(region++, 0, 32, + MPU_ACR_XN | MPU_RGN_STRONGLY_ORDERED | MPU_AP_PL1RW_PL0NA); + + /* RAM */ + err |= mpu_setup_region(region++, PHYS_OFFSET, + ilog2(memblock.memory.regions[0].size), + MPU_AP_PL1RW_PL0RW | MPU_RGN_NORMAL); + + /* Vectors */ + err |= mpu_setup_region(region++, vectors_base, + ilog2(2 * PAGE_SIZE), + MPU_AP_PL1RW_PL0NA | MPU_RGN_NORMAL); + if (err) { + panic("MPU region initialization failure! %d", err); } else { pr_info("Using ARMv7 PMSA Compliant MPU. " - "Region independence: %s, Max regions: %d\n", + "Region independence: %s, Used %d of %d regions\n", mpu_iside_independent() ? "Yes" : "No", - mpu_max_regions()); + mpu_rgn_info.used, mpu_max_regions); } } |