From 046835b4aa22b9ab6aa0bb274e3b71047c4b887d Mon Sep 17 00:00:00 2001 From: Vladimir Murzin Date: Tue, 3 Apr 2018 10:39:23 +0100 Subject: ARM: 8757/1: NOMMU: Support PMSAv8 MPU ARMv8R/M architecture defines new memory protection scheme - PMSAv8 which is not compatible with PMSAv7. Key differences to PMSAv7 are: - Region geometry is defined by base and limit addresses - Addresses need to be either 32 or 64 byte aligned - No region priority due to overlapping regions are not allowed - It is unified, i.e. no distinction between data/instruction regions - Memory attributes are controlled via MAIR This patch implements support for PMSAv8 MPU defined by ARMv8R/M architecture. Signed-off-by: Vladimir Murzin Signed-off-by: Russell King --- arch/arm/mm/pmsa-v8.c | 307 ++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 307 insertions(+) create mode 100644 arch/arm/mm/pmsa-v8.c (limited to 'arch/arm/mm/pmsa-v8.c') diff --git a/arch/arm/mm/pmsa-v8.c b/arch/arm/mm/pmsa-v8.c new file mode 100644 index 000000000000..617a83def88a --- /dev/null +++ b/arch/arm/mm/pmsa-v8.c @@ -0,0 +1,307 @@ +/* + * Based on linux/arch/arm/pmsa-v7.c + * + * ARM PMSAv8 supporting functions. + */ + +#include +#include + +#include +#include +#include + +#include +#include + +#include "mm.h" + +#ifndef CONFIG_CPU_V7M + +#define PRSEL __ACCESS_CP15(c6, 0, c2, 1) +#define PRBAR __ACCESS_CP15(c6, 0, c3, 0) +#define PRLAR __ACCESS_CP15(c6, 0, c3, 1) + +static inline u32 prlar_read(void) +{ + return read_sysreg(PRLAR); +} + +static inline u32 prbar_read(void) +{ + return read_sysreg(PRBAR); +} + +static inline void prsel_write(u32 v) +{ + write_sysreg(v, PRSEL); +} + +static inline void prbar_write(u32 v) +{ + write_sysreg(v, PRBAR); +} + +static inline void prlar_write(u32 v) +{ + write_sysreg(v, PRLAR); +} +#else + +static inline u32 prlar_read(void) +{ + return readl_relaxed(BASEADDR_V7M_SCB + PMSAv8_RLAR); +} + +static inline u32 prbar_read(void) +{ + return readl_relaxed(BASEADDR_V7M_SCB + PMSAv8_RBAR); +} + +static inline void prsel_write(u32 v) +{ + writel_relaxed(v, BASEADDR_V7M_SCB + PMSAv8_RNR); +} + +static inline void prbar_write(u32 v) +{ + writel_relaxed(v, BASEADDR_V7M_SCB + PMSAv8_RBAR); +} + +static inline void prlar_write(u32 v) +{ + writel_relaxed(v, BASEADDR_V7M_SCB + PMSAv8_RLAR); +} + +#endif + +static struct range __initdata io[MPU_MAX_REGIONS]; +static struct range __initdata mem[MPU_MAX_REGIONS]; + +static unsigned int __initdata mpu_max_regions; + +static __init bool is_region_fixed(int number) +{ + switch (number) { + case PMSAv8_XIP_REGION: + case PMSAv8_KERNEL_REGION: + return true; + default: + return false; + } +} + +void __init pmsav8_adjust_lowmem_bounds(void) +{ + phys_addr_t mem_end; + struct memblock_region *reg; + bool first = true; + + for_each_memblock(memory, reg) { + if (first) { + phys_addr_t phys_offset = PHYS_OFFSET; + + /* + * Initially only use memory continuous from + * PHYS_OFFSET */ + if (reg->base != phys_offset) + panic("First memory bank must be contiguous from PHYS_OFFSET"); + mem_end = reg->base + reg->size; + first = false; + } else { + /* + * memblock auto merges contiguous blocks, remove + * all blocks afterwards in one go (we can't remove + * blocks separately while iterating) + */ + pr_notice("Ignoring RAM after %pa, memory at %pa ignored\n", + &mem_end, ®->base); + memblock_remove(reg->base, 0 - reg->base); + break; + } + } +} + +static int __init __mpu_max_regions(void) +{ + static int max_regions; + u32 mpuir; + + if (max_regions) + return max_regions; + + mpuir = read_cpuid_mputype(); + + max_regions = (mpuir & MPUIR_DREGION_SZMASK) >> MPUIR_DREGION; + + return max_regions; +} + +static int __init __pmsav8_setup_region(unsigned int number, u32 bar, u32 lar) +{ + if (number > mpu_max_regions + || number >= MPU_MAX_REGIONS) + return -ENOENT; + + dsb(); + prsel_write(number); + isb(); + prbar_write(bar); + prlar_write(lar); + + mpu_rgn_info.rgns[number].prbar = bar; + mpu_rgn_info.rgns[number].prlar = lar; + + mpu_rgn_info.used++; + + return 0; +} + +static int __init pmsav8_setup_ram(unsigned int number, phys_addr_t start,phys_addr_t end) +{ + u32 bar, lar; + + if (is_region_fixed(number)) + return -EINVAL; + + bar = start; + lar = (end - 1) & ~(PMSAv8_MINALIGN - 1);; + + bar |= PMSAv8_AP_PL1RW_PL0RW | PMSAv8_RGN_SHARED; + lar |= PMSAv8_LAR_IDX(PMSAv8_RGN_NORMAL) | PMSAv8_LAR_EN; + + return __pmsav8_setup_region(number, bar, lar); +} + +static int __init pmsav8_setup_io(unsigned int number, phys_addr_t start,phys_addr_t end) +{ + u32 bar, lar; + + if (is_region_fixed(number)) + return -EINVAL; + + bar = start; + lar = (end - 1) & ~(PMSAv8_MINALIGN - 1);; + + bar |= PMSAv8_AP_PL1RW_PL0RW | PMSAv8_RGN_SHARED | PMSAv8_BAR_XN; + lar |= PMSAv8_LAR_IDX(PMSAv8_RGN_DEVICE_nGnRnE) | PMSAv8_LAR_EN; + + return __pmsav8_setup_region(number, bar, lar); +} + +static int __init pmsav8_setup_fixed(unsigned int number, phys_addr_t start,phys_addr_t end) +{ + u32 bar, lar; + + if (!is_region_fixed(number)) + return -EINVAL; + + bar = start; + lar = (end - 1) & ~(PMSAv8_MINALIGN - 1); + + bar |= PMSAv8_AP_PL1RW_PL0NA | PMSAv8_RGN_SHARED; + lar |= PMSAv8_LAR_IDX(PMSAv8_RGN_NORMAL) | PMSAv8_LAR_EN; + + prsel_write(number); + isb(); + + if (prbar_read() != bar || prlar_read() != lar) + return -EINVAL; + + /* Reserved region was set up early, we just need a record for secondaries */ + mpu_rgn_info.rgns[number].prbar = bar; + mpu_rgn_info.rgns[number].prlar = lar; + + mpu_rgn_info.used++; + + return 0; +} + +#ifndef CONFIG_CPU_V7M +static int __init pmsav8_setup_vector(unsigned int number, phys_addr_t start,phys_addr_t end) +{ + u32 bar, lar; + + if (number == PMSAv8_KERNEL_REGION) + return -EINVAL; + + bar = start; + lar = (end - 1) & ~(PMSAv8_MINALIGN - 1); + + bar |= PMSAv8_AP_PL1RW_PL0NA | PMSAv8_RGN_SHARED; + lar |= PMSAv8_LAR_IDX(PMSAv8_RGN_NORMAL) | PMSAv8_LAR_EN; + + return __pmsav8_setup_region(number, bar, lar); +} +#endif + +void __init pmsav8_setup(void) +{ + int i, err = 0; + int region = PMSAv8_KERNEL_REGION; + + /* How many regions are supported ? */ + mpu_max_regions = __mpu_max_regions(); + + /* RAM: single chunk of memory */ + add_range(mem, ARRAY_SIZE(mem), 0, memblock.memory.regions[0].base, + memblock.memory.regions[0].base + memblock.memory.regions[0].size); + + /* IO: cover full 4G range */ + add_range(io, ARRAY_SIZE(io), 0, 0, 0xffffffff); + + /* RAM and IO: exclude kernel */ + subtract_range(mem, ARRAY_SIZE(mem), __pa(KERNEL_START), __pa(KERNEL_END)); + subtract_range(io, ARRAY_SIZE(io), __pa(KERNEL_START), __pa(KERNEL_END)); + +#ifdef CONFIG_XIP_KERNEL + /* RAM and IO: exclude xip */ + subtract_range(mem, ARRAY_SIZE(mem), CONFIG_XIP_PHYS_ADDR, __pa(_exiprom)); + subtract_range(io, ARRAY_SIZE(io), CONFIG_XIP_PHYS_ADDR, __pa(_exiprom)); +#endif + +#ifndef CONFIG_CPU_V7M + /* RAM and IO: exclude vectors */ + subtract_range(mem, ARRAY_SIZE(mem), vectors_base, vectors_base + 2 * PAGE_SIZE); + subtract_range(io, ARRAY_SIZE(io), vectors_base, vectors_base + 2 * PAGE_SIZE); +#endif + /* IO: exclude RAM */ + for (i = 0; i < ARRAY_SIZE(mem); i++) + subtract_range(io, ARRAY_SIZE(io), mem[i].start, mem[i].end); + + /* Now program MPU */ + +#ifdef CONFIG_XIP_KERNEL + /* ROM */ + err |= pmsav8_setup_fixed(PMSAv8_XIP_REGION, CONFIG_XIP_PHYS_ADDR, __pa(_exiprom)); +#endif + /* Kernel */ + err |= pmsav8_setup_fixed(region++, __pa(KERNEL_START), __pa(KERNEL_END)); + + + /* IO */ + for (i = 0; i < ARRAY_SIZE(io); i++) { + if (!io[i].end) + continue; + + err |= pmsav8_setup_io(region++, io[i].start, io[i].end); + } + + /* RAM */ + for (i = 0; i < ARRAY_SIZE(mem); i++) { + if (!mem[i].end) + continue; + + err |= pmsav8_setup_ram(region++, mem[i].start, mem[i].end); + } + + /* Vectors */ +#ifndef CONFIG_CPU_V7M + err |= pmsav8_setup_vector(region++, vectors_base, vectors_base + 2 * PAGE_SIZE); +#endif + if (err) + pr_warn("MPU region initialization failure! %d", err); + else + pr_info("Using ARM PMSAv8 Compliant MPU. Used %d of %d regions\n", + mpu_rgn_info.used, mpu_max_regions); +} -- cgit v1.2.3-59-g8ed1b