This commit adds basic mmu support, ie: - DMA cache handling is not supported - Remapping memory region also The current mmu setting is: - 4KB granularity - 3 level lookup (skipping L0) - 33 bits per VA This is based on coreboot and u-boot mmu configuration. Signed-off-by: Raphael Poggi <poggi.raph@xxxxxxxxx> --- arch/arm64/cpu/Makefile | 2 +- arch/arm64/cpu/cpu.c | 19 --- arch/arm64/cpu/interrupts.c | 6 - arch/arm64/cpu/mmu-early.h | 6 - arch/arm64/cpu/mmu.c | 334 +++++++++++++++++++++++++++++++++++++++ arch/arm64/cpu/mmu.h | 155 ++++++++++++++++++ arch/arm64/cpu/start.c | 4 +- arch/arm64/include/asm/mmu.h | 6 +- arch/arm64/include/asm/pgtable.h | 5 +- include/asm-generic/sections.h | 6 +- 10 files changed, 500 insertions(+), 43 deletions(-) delete mode 100644 arch/arm64/cpu/mmu-early.h create mode 100644 arch/arm64/cpu/mmu.c diff --git a/arch/arm64/cpu/Makefile b/arch/arm64/cpu/Makefile index 1880c32..fe6e7af 100644 --- a/arch/arm64/cpu/Makefile +++ b/arch/arm64/cpu/Makefile @@ -8,7 +8,7 @@ obj-y += start.o entry.o # obj-$(CONFIG_CMD_ARM_CPUINFO) += cpuinfo.o obj-$(CONFIG_CMD_ARM_MMUINFO) += mmuinfo.o -obj-$(CONFIG_MMU) += cache.o +obj-$(CONFIG_MMU) += mmu.o cache.o AFLAGS_cache-armv8.o :=-Wa,-march=armv8-a obj-$(CONFIG_CPU_64v8) += cache-armv8.o diff --git a/arch/arm64/cpu/cpu.c b/arch/arm64/cpu/cpu.c index 2a27e72..19cd944 100644 --- a/arch/arm64/cpu/cpu.c +++ b/arch/arm64/cpu/cpu.c @@ -61,25 +61,6 @@ int icache_status(void) return (get_sctlr() & CR_I) != 0; } -/* - * SoC like the ux500 have the l2x0 always enable - * with or without MMU enable - */ -struct outer_cache_fns outer_cache; - -/* - * Clean and invalide caches, disable MMU - */ -void mmu_disable(void) -{ - __mmu_cache_flush(); - if (outer_cache.disable) { - outer_cache.flush_all(); - outer_cache.disable(); - } - __mmu_cache_off(); -} - /** * Disable MMU and D-cache, flush caches * @return 0 (always) diff --git a/arch/arm64/cpu/interrupts.c b/arch/arm64/cpu/interrupts.c index 32f5b4b..d42a5b1 100644 --- a/arch/arm64/cpu/interrupts.c +++ b/arch/arm64/cpu/interrupts.c @@ -75,12 +75,6 @@ void do_prefetch_abort (struct pt_regs *pt_regs) */ void do_data_abort (struct pt_regs *pt_regs) { - u32 far; - - printf("unable to handle %s at address 0x%08x\n", - far < PAGE_SIZE ? "NULL pointer dereference" : - "paging request", far); - do_exception(pt_regs); } diff --git a/arch/arm64/cpu/mmu-early.h b/arch/arm64/cpu/mmu-early.h deleted file mode 100644 index af21f52..0000000 --- a/arch/arm64/cpu/mmu-early.h +++ /dev/null @@ -1,6 +0,0 @@ -#ifndef __ARM_CPU_MMU_EARLY_H -#define __ARM_CPU_MMU_EARLY_H - -void mmu_early_enable(uint32_t membase, uint32_t memsize, uint32_t ttb); - -#endif /* __ARM_CPU_MMU_EARLY_H */ diff --git a/arch/arm64/cpu/mmu.c b/arch/arm64/cpu/mmu.c new file mode 100644 index 0000000..b171f80 --- /dev/null +++ b/arch/arm64/cpu/mmu.c @@ -0,0 +1,334 @@ +/* + * Copyright (c) 2009-2013 Sascha Hauer <s.hauer@xxxxxxxxxxxxxx>, Pengutronix + * + * See file CREDITS for list of people who contributed to this + * project. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 + * as published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + */ + +#define pr_fmt(fmt) "mmu: " fmt + +#include <common.h> +#include <dma-dir.h> +#include <init.h> +#include <mmu.h> +#include <errno.h> +#include <linux/sizes.h> +#include <asm/memory.h> +#include <asm/barebox-arm.h> +#include <asm/system.h> +#include <asm/cache.h> +#include <memory.h> +#include <asm/system_info.h> + +#include "mmu.h" + +static uint64_t *ttb; +static int free_idx; + +static void arm_mmu_not_initialized_error(void) +{ + /* + * This means: + * - one of the MMU functions like dma_alloc_coherent + * or remap_range is called too early, before the MMU is initialized + * - Or the MMU initialization has failed earlier + */ + panic("MMU not initialized\n"); +} + + +/* + * Do it the simple way for now and invalidate the entire + * tlb + */ +static inline void tlb_invalidate(void) +{ + unsigned int el = current_el(); + + dsb(); + + if (el == 1) + __asm__ __volatile__("tlbi alle1\n\t" : : : "memory"); + else if (el == 2) + __asm__ __volatile__("tlbi alle2\n\t" : : : "memory"); + else if (el == 3) + __asm__ __volatile__("tlbi alle3\n\t" : : : "memory"); + + dsb(); + isb(); +} + +static int level2shift(int level) +{ + /* Page is 12 bits wide, every level translates 9 bits */ + return (12 + 9 * (3 - level)); +} + +static uint64_t level2mask(int level) +{ + uint64_t mask = -EINVAL; + + if (level == 1) + mask = L1_ADDR_MASK; + else if (level == 2) + mask = L2_ADDR_MASK; + else if (level == 3) + mask = L3_ADDR_MASK; + + return mask; +} + +static int pte_type(uint64_t *pte) +{ + return *pte & PMD_TYPE_MASK; +} + +static void set_table(uint64_t *pt, uint64_t *table_addr) +{ + uint64_t val; + + val = PMD_TYPE_TABLE | (uint64_t)table_addr; + *pt = val; +} + +static uint64_t *create_table(void) +{ + uint64_t *new_table = ttb + free_idx * GRANULE_SIZE; + + /* Mark all entries as invalid */ + memset(new_table, 0, GRANULE_SIZE); + + free_idx++; + + return new_table; +} + +static uint64_t *get_level_table(uint64_t *pte) +{ + uint64_t *table = (uint64_t *)(*pte & XLAT_ADDR_MASK); + + if (pte_type(pte) != PMD_TYPE_TABLE) { + table = create_table(); + set_table(pte, table); + } + + return table; +} + +static uint64_t *find_pte(uint64_t addr) +{ + uint64_t *pte; + uint64_t block_shift; + uint64_t idx; + int i; + + pte = ttb; + + for (i = 1; i < 4; i++) { + block_shift = level2shift(i); + idx = (addr & level2mask(i)) >> block_shift; + pte += idx; + + if ((pte_type(pte) != PMD_TYPE_TABLE) || (block_shift <= GRANULE_SIZE_SHIFT)) + break; + else + pte = (uint64_t *)(*pte & XLAT_ADDR_MASK); + } + + return pte; +} + +static void map_region(uint64_t virt, uint64_t phys, uint64_t size, uint64_t attr) +{ + uint64_t block_size; + uint64_t block_shift; + uint64_t *pte; + uint64_t idx; + uint64_t addr; + uint64_t *table; + int level; + + if (!ttb) + arm_mmu_not_initialized_error(); + + addr = virt; + + attr &= ~(PMD_TYPE_SECT); + + while (size) { + table = ttb; + for (level = 1; level < 4; level++) { + block_shift = level2shift(level); + idx = (addr & level2mask(level)) >> block_shift; + block_size = (1 << block_shift); + + pte = table + idx; + + if (level == 3) + attr |= PMD_TYPE_PAGE; + else + attr |= PMD_TYPE_SECT; + + if (size >= block_size && IS_ALIGNED(addr, block_size)) { + *pte = phys | attr; + addr += block_size; + phys += block_size; + size -= block_size; + break; + + } + + table = get_level_table(pte); + } + + } +} + +static void create_sections(uint64_t virt, uint64_t phys, uint64_t size_m, uint64_t flags) +{ + + map_region(virt, phys, size_m, flags); +} + +void *map_io_sections(uint64_t phys, void *_start, size_t size) +{ + + map_region((uint64_t)_start, phys, (uint64_t)size, PMD_SECT_DEF_UNCACHED); + + tlb_invalidate(); + return _start; +} + + +int arch_remap_range(void *_start, size_t size, unsigned flags) +{ + map_region((uint64_t)_start, (uint64_t)_start, (uint64_t)size, flags); + + return 0; +} + +/* + * Prepare MMU for usage enable it. + */ +static int mmu_init(void) +{ + struct memory_bank *bank; + + if (list_empty(&memory_banks)) + /* + * If you see this it means you have no memory registered. + * This can be done either with arm_add_mem_device() in an + * initcall prior to mmu_initcall or via devicetree in the + * memory node. + */ + panic("MMU: No memory bank found! Cannot continue\n"); + + if (get_sctlr() & CR_M) { + ttb = (uint64_t *)get_ttbr(1); + if (!request_sdram_region("ttb", (unsigned long)ttb, SZ_16K)) + /* + * This can mean that: + * - the early MMU code has put the ttb into a place + * which we don't have inside our available memory + * - Somebody else has occupied the ttb region which means + * the ttb will get corrupted. + */ + pr_crit("Critical Error: Can't request SDRAM region for ttb at %p\n", + ttb); + } else { + ttb = memalign(0x1000, SZ_16K); + free_idx = 1; + + memset(ttb, 0, GRANULE_SIZE); + + set_ttbr_tcr_mair(current_el(), (uint64_t)ttb, TCR_FLAGS, MEMORY_ATTR); + } + + pr_debug("ttb: 0x%p\n", ttb); + + /* create a flat mapping using 1MiB sections */ + create_sections(0, 0, GRANULE_SIZE, PMD_SECT_AP_WRITE | PMD_SECT_AP_READ | PMD_TYPE_SECT); + + /* + * First remap sdram cached using sections. + * This is to speed up the generation of 2nd level page tables + * below + */ + for_each_memory_bank(bank) + create_sections(bank->start, bank->start, bank->size, PMD_SECT_DEF_CACHED); + + return 0; +} +mmu_initcall(mmu_init); + +void mmu_enable(void) +{ + if (!ttb) + arm_mmu_not_initialized_error(); + + if (!(get_sctlr() & CR_M)) { + + isb(); + set_sctlr(get_sctlr() | CR_M | CR_C | CR_I); + } +} + +void mmu_disable(void) +{ + unsigned int sctlr; + + if (!ttb) + arm_mmu_not_initialized_error(); + + sctlr = get_sctlr(); + sctlr &= ~(CR_M | CR_C | CR_I); + + tlb_invalidate(); + + dsb(); + isb(); + + set_sctlr(sctlr); + + dsb(); + isb(); +} + +void mmu_early_enable(uint64_t membase, uint64_t memsize, uint64_t _ttb) +{ + ttb = (uint64_t *)_ttb; + + memset(ttb, 0, GRANULE_SIZE); + free_idx = 1; + + set_ttbr_tcr_mair(current_el(), (uint64_t)ttb, TCR_FLAGS, MEMORY_ATTR); + + create_sections(0, 0, 4096, PMD_SECT_AP_WRITE | + PMD_SECT_AP_READ | PMD_TYPE_SECT); + + create_sections(membase, membase, memsize, PMD_SECT_AP_WRITE | + PMD_SECT_AP_READ | PMD_TYPE_SECT | PMD_SECT_WB); + + isb(); + set_sctlr(get_sctlr() | CR_M); +} + +unsigned long virt_to_phys(volatile void *virt) +{ + return (unsigned long)virt; +} + +void *phys_to_virt(unsigned long phys) +{ + return (void *)phys; +} diff --git a/arch/arm64/cpu/mmu.h b/arch/arm64/cpu/mmu.h index 79ebc80..a20adec 100644 --- a/arch/arm64/cpu/mmu.h +++ b/arch/arm64/cpu/mmu.h @@ -1,6 +1,159 @@ #ifndef __ARM_MMU_H #define __ARM_MMU_H +#define UL(x) _AC(x, UL) + +#define UNUSED_DESC 0x6EbAAD0BBADbA6E0 + +#define VA_START 0x0 +#define BITS_PER_VA 33 + +/* Granule size of 4KB is being used */ +#define GRANULE_SIZE_SHIFT 12 +#define GRANULE_SIZE (1 << GRANULE_SIZE_SHIFT) +#define XLAT_ADDR_MASK ((1UL << BITS_PER_VA) - GRANULE_SIZE) +#define GRANULE_SIZE_MASK ((1 << GRANULE_SIZE_SHIFT) - 1) + +#define BITS_RESOLVED_PER_LVL (GRANULE_SIZE_SHIFT - 3) +#define L1_ADDR_SHIFT (GRANULE_SIZE_SHIFT + BITS_RESOLVED_PER_LVL * 2) +#define L2_ADDR_SHIFT (GRANULE_SIZE_SHIFT + BITS_RESOLVED_PER_LVL * 1) +#define L3_ADDR_SHIFT (GRANULE_SIZE_SHIFT + BITS_RESOLVED_PER_LVL * 0) + + +#define L1_ADDR_MASK (((1UL << BITS_RESOLVED_PER_LVL) - 1) << L1_ADDR_SHIFT) +#define L2_ADDR_MASK (((1UL << BITS_RESOLVED_PER_LVL) - 1) << L2_ADDR_SHIFT) +#define L3_ADDR_MASK (((1UL << BITS_RESOLVED_PER_LVL) - 1) << L3_ADDR_SHIFT) + +/* These macros give the size of the region addressed by each entry of a xlat + table at any given level */ +#define L3_XLAT_SIZE (1UL << L3_ADDR_SHIFT) +#define L2_XLAT_SIZE (1UL << L2_ADDR_SHIFT) +#define L1_XLAT_SIZE (1UL << L1_ADDR_SHIFT) + +#define GRANULE_MASK GRANULE_SIZE + +/* + * Memory types + */ +#define MT_DEVICE_NGNRNE 0 +#define MT_DEVICE_NGNRE 1 +#define MT_DEVICE_GRE 2 +#define MT_NORMAL_NC 3 +#define MT_NORMAL 4 + +#define MEMORY_ATTRIBUTES ((0x00 << (MT_DEVICE_NGNRNE*8)) | \ + (0x04 << (MT_DEVICE_NGNRE*8)) | \ + (0x0c << (MT_DEVICE_GRE*8)) | \ + (0x44 << (MT_NORMAL_NC*8)) | \ + (UL(0xff) << (MT_NORMAL*8))) + +/* + * Hardware page table definitions. + * + * Level 2 descriptor (PMD). + */ +#define PMD_TYPE_MASK (3 << 0) +#define PMD_TYPE_FAULT (0 << 0) +#define PMD_TYPE_TABLE (3 << 0) +#define PMD_TYPE_PAGE (3 << 0) +#define PMD_TYPE_SECT (1 << 0) + +/* + * Section + */ +#define PMD_SECT_NON_SHARE (0 << 8) +#define PMD_SECT_OUTER_SHARE (2 << 8) +#define PMD_SECT_INNER_SHARE (3 << 8) +#define PMD_SECT_AF (1 << 10) +#define PMD_SECT_NG (1 << 11) +#define PMD_SECT_PXN (UL(1) << 53) +#define PMD_SECT_UXN (UL(1) << 54) + +/* + * AttrIndx[2:0] + */ +#define PMD_ATTRINDX(t) ((t) << 2) +#define PMD_ATTRINDX_MASK (7 << 2) + +/* + * TCR flags. + */ +#define TCR_T0SZ(x) ((64 - (x)) << 0) +#define TCR_IRGN_NC (0 << 8) +#define TCR_IRGN_WBWA (1 << 8) +#define TCR_IRGN_WT (2 << 8) +#define TCR_IRGN_WBNWA (3 << 8) +#define TCR_IRGN_MASK (3 << 8) +#define TCR_ORGN_NC (0 << 10) +#define TCR_ORGN_WBWA (1 << 10) +#define TCR_ORGN_WT (2 << 10) +#define TCR_ORGN_WBNWA (3 << 10) +#define TCR_ORGN_MASK (3 << 10) +#define TCR_SHARED_NON (0 << 12) +#define TCR_SHARED_OUTER (2 << 12) +#define TCR_SHARED_INNER (3 << 12) +#define TCR_TG0_4K (0 << 14) +#define TCR_TG0_64K (1 << 14) +#define TCR_TG0_16K (2 << 14) +#define TCR_EL1_IPS_BITS (UL(3) << 32) /* 42 bits physical address */ +#define TCR_EL2_IPS_BITS (3 << 16) /* 42 bits physical address */ +#define TCR_EL3_IPS_BITS (3 << 16) /* 42 bits physical address */ + +#define TCR_EL1_RSVD (1 << 31) +#define TCR_EL2_RSVD (1 << 31 | 1 << 23) +#define TCR_EL3_RSVD (1 << 31 | 1 << 23) + +#define TCR_FLAGS (TCR_TG0_4K | \ + TCR_SHARED_OUTER | \ + TCR_SHARED_INNER | \ + TCR_IRGN_WBWA | \ + TCR_ORGN_WBWA | \ + TCR_T0SZ(BITS_PER_VA)) + +#define MEMORY_ATTR (PMD_SECT_AF | PMD_SECT_INNER_SHARE | \ + PMD_ATTRINDX(MT_NORMAL) | \ + PMD_TYPE_SECT) + +#ifndef __ASSEMBLY__ + +static inline void set_ttbr_tcr_mair(int el, uint64_t table, uint64_t tcr, uint64_t attr) +{ + asm volatile("dsb sy"); + if (el == 1) { + asm volatile("msr ttbr0_el1, %0" : : "r" (table) : "memory"); + asm volatile("msr tcr_el1, %0" : : "r" (tcr) : "memory"); + asm volatile("msr mair_el1, %0" : : "r" (attr) : "memory"); + } else if (el == 2) { + asm volatile("msr ttbr0_el2, %0" : : "r" (table) : "memory"); + asm volatile("msr tcr_el2, %0" : : "r" (tcr) : "memory"); + asm volatile("msr mair_el2, %0" : : "r" (attr) : "memory"); + } else if (el == 3) { + asm volatile("msr ttbr0_el3, %0" : : "r" (table) : "memory"); + asm volatile("msr tcr_el3, %0" : : "r" (tcr) : "memory"); + asm volatile("msr mair_el3, %0" : : "r" (attr) : "memory"); + } else { + hang(); + } + asm volatile("isb"); +} + +static inline uint64_t get_ttbr(int el) +{ + uint64_t val; + if (el == 1) { + asm volatile("mrs %0, ttbr0_el1" : "=r" (val)); + } else if (el == 2) { + asm volatile("mrs %0, ttbr0_el2" : "=r" (val)); + } else if (el == 3) { + asm volatile("mrs %0, ttbr0_el3" : "=r" (val)); + } else { + hang(); + } + + return val; +} +#endif + #ifdef CONFIG_MMU void __mmu_cache_on(void); void __mmu_cache_off(void); @@ -11,4 +164,6 @@ static inline void __mmu_cache_off(void) {} static inline void __mmu_cache_flush(void) {} #endif +void mmu_early_enable(uint64_t membase, uint64_t memsize, uint64_t _ttb); + #endif /* __ARM_MMU_H */ diff --git a/arch/arm64/cpu/start.c b/arch/arm64/cpu/start.c index e4a48e3..1d017bc 100644 --- a/arch/arm64/cpu/start.c +++ b/arch/arm64/cpu/start.c @@ -31,7 +31,7 @@ #include <malloc.h> #include <debug_ll.h> -#include "mmu-early.h" +#include "mmu.h" unsigned long arm_stack_top; static unsigned long arm_head_bottom; @@ -170,7 +170,7 @@ __noreturn void barebox_non_pbl_start(unsigned long membase, } else { pr_debug("enabling MMU, ttb @ 0x%08lx\n", ttb); arm_early_mmu_cache_invalidate(); - mmu_early_enable(membase, memsize, ttb); + mmu_early_enable((uint64_t)membase, (uint64_t)memsize, (uint64_t)ttb); } } diff --git a/arch/arm64/include/asm/mmu.h b/arch/arm64/include/asm/mmu.h index 8de6544..8a1d80a 100644 --- a/arch/arm64/include/asm/mmu.h +++ b/arch/arm64/include/asm/mmu.h @@ -13,9 +13,7 @@ struct arm_memory; -static inline void mmu_enable(void) -{ -} +void mmu_enable(void); void mmu_disable(void); static inline void arm_create_section(unsigned long virt, unsigned long phys, int size_m, unsigned int flags) @@ -30,7 +28,7 @@ static inline void setup_dma_coherent(unsigned long offset) #define ARCH_HAS_REMAP #define MAP_ARCH_DEFAULT MAP_CACHED int arch_remap_range(void *_start, size_t size, unsigned flags); -void *map_io_sections(unsigned long physaddr, void *start, size_t size); +void *map_io_sections(uint64_t phys, void *_start, size_t size); #else #define MAP_ARCH_DEFAULT MAP_UNCACHED static inline void *map_io_sections(unsigned long phys, void *start, size_t size) diff --git a/arch/arm64/include/asm/pgtable.h b/arch/arm64/include/asm/pgtable.h index fd1521d..e4a3c53 100644 --- a/arch/arm64/include/asm/pgtable.h +++ b/arch/arm64/include/asm/pgtable.h @@ -18,8 +18,9 @@ */ #define PMD_TYPE_MASK (3 << 0) #define PMD_TYPE_FAULT (0 << 0) -#define PMD_TYPE_TABLE (1 << 0) -#define PMD_TYPE_SECT (2 << 0) +#define PMD_TYPE_TABLE (3 << 0) +#define PMD_TYPE_PAGE (3 << 0) +#define PMD_TYPE_SECT (1 << 0) #define PMD_BIT4 (1 << 4) #define PMD_DOMAIN(x) ((x) << 5) #define PMD_PROTECTION (1 << 9) /* v5 */ diff --git a/include/asm-generic/sections.h b/include/asm-generic/sections.h index 984f8b6..e08fb72 100644 --- a/include/asm-generic/sections.h +++ b/include/asm-generic/sections.h @@ -11,8 +11,8 @@ extern void *_barebox_image_size; extern void *_barebox_bare_init_size; extern void *_barebox_pbl_size; -#define barebox_image_size (unsigned int)&_barebox_image_size -#define barebox_bare_init_size (unsigned int)&_barebox_bare_init_size -#define barebox_pbl_size (unsigned int)&_barebox_pbl_size +#define barebox_image_size ((uint64_t)&_barebox_image_size) +#define barebox_bare_init_size ((uint64_t)&_barebox_bare_init_size) +#define barebox_pbl_size ((uint64_t)&_barebox_pbl_size) #endif /* _ASM_GENERIC_SECTIONS_H_ */ -- 2.1.0 _______________________________________________ barebox mailing list barebox@xxxxxxxxxxxxxxxxxxx http://lists.infradead.org/mailman/listinfo/barebox