diff --git a/src/target/riscv/riscv.c b/src/target/riscv/riscv.c index 4b5d67e21..aa4bc6757 100644 --- a/src/target/riscv/riscv.c +++ b/src/target/riscv/riscv.c @@ -3086,6 +3086,21 @@ static int riscv_virt2phys(struct target *target, target_addr_t virtual, target_ virtual, physical); } +static int check_virt_memory_access(struct target *target, target_addr_t address, + uint32_t size, uint32_t count, bool is_write) +{ + const bool is_misaligned = address % size != 0; + // TODO: This assumes that size of each page is 4 KiB, which is not necessarily the case. + const bool crosses_page_boundary = RISCV_PGBASE(address + size * count - 1) != RISCV_PGBASE(address); + if (is_misaligned && crosses_page_boundary) { + LOG_TARGET_ERROR(target, "Mis-aligned memory %s (address=0x%" TARGET_PRIxADDR ", size=%d, count=%d)" + " would access an element across page boundary. This is not supported.", + is_write ? "write" : "read", address, size, count); + return ERROR_FAIL; + } + return ERROR_OK; +} + static int riscv_read_phys_memory(struct target *target, target_addr_t phys_address, uint32_t size, uint32_t count, uint8_t *buffer) { @@ -3093,25 +3108,6 @@ static int riscv_read_phys_memory(struct target *target, target_addr_t phys_addr return r->read_memory(target, phys_address, size, count, buffer, size); } -static int riscv_read_memory(struct target *target, target_addr_t address, - uint32_t size, uint32_t count, uint8_t *buffer) -{ - if (count == 0) { - LOG_TARGET_WARNING(target, "0-length read from 0x%" TARGET_PRIxADDR, address); - return ERROR_OK; - } - - target_addr_t physical_addr; - int result = target->type->virt2phys(target, address, &physical_addr); - if (result != ERROR_OK) { - LOG_TARGET_ERROR(target, "Address translation failed."); - return result; - } - - RISCV_INFO(r); - return r->read_memory(target, physical_addr, size, count, buffer, size); -} - static int riscv_write_phys_memory(struct target *target, target_addr_t phys_address, uint32_t size, uint32_t count, const uint8_t *buffer) { @@ -3121,25 +3117,76 @@ static int riscv_write_phys_memory(struct target *target, target_addr_t phys_add return tt->write_memory(target, phys_address, size, count, buffer); } -static int riscv_write_memory(struct target *target, target_addr_t address, - uint32_t size, uint32_t count, const uint8_t *buffer) +static int riscv_rw_memory(struct target *target, target_addr_t address, uint32_t size, + uint32_t count, uint8_t *read_buffer, const uint8_t *write_buffer) { + /* Exactly one of the buffers must be set, the other must be NULL */ + assert(!!read_buffer != !!write_buffer); + + const bool is_write = write_buffer ? true : false; if (count == 0) { - LOG_TARGET_WARNING(target, "0-length write to 0x%" TARGET_PRIxADDR, address); + LOG_TARGET_WARNING(target, "0-length %s 0x%" TARGET_PRIxADDR, + is_write ? "write to" : "read from", address); return ERROR_OK; } - target_addr_t physical_addr; - int result = target->type->virt2phys(target, address, &physical_addr); - if (result != ERROR_OK) { - LOG_TARGET_ERROR(target, "Address translation failed."); + int mmu_enabled; + int result = riscv_mmu(target, &mmu_enabled); + if (result != ERROR_OK) return result; - } + RISCV_INFO(r); struct target_type *tt = get_target_type(target); if (!tt) return ERROR_FAIL; - return tt->write_memory(target, physical_addr, size, count, buffer); + + if (!mmu_enabled) { + if (is_write) + return tt->write_memory(target, address, size, count, write_buffer); + else + return r->read_memory(target, address, size, count, read_buffer, size); + } + + result = check_virt_memory_access(target, address, size, count, is_write); + if (result != ERROR_OK) + return result; + + uint32_t current_count = 0; + while (current_count < count) { + target_addr_t physical_addr; + result = target->type->virt2phys(target, address, &physical_addr); + if (result != ERROR_OK) { + LOG_TARGET_ERROR(target, "Address translation failed."); + return result; + } + + /* TODO: For simplicity, this algorithm assumes the worst case - the smallest possible page size, + * which is 4 KiB. The algorithm can be improved to detect the real page size, and allow to use larger + * memory transfers and avoid extra unnecessary virt2phys address translations. */ + uint32_t chunk_count = MIN(count - current_count, (RISCV_PGSIZE - RISCV_PGOFFSET(address)) / size); + if (is_write) + result = tt->write_memory(target, physical_addr, size, chunk_count, write_buffer + current_count * size); + else + result = r->read_memory(target, physical_addr, size, chunk_count, read_buffer + current_count * size, size); + if (result != ERROR_OK) + return result; + + current_count += chunk_count; + address += chunk_count * size; + } + return ERROR_OK; +} + +static int riscv_read_memory(struct target *target, target_addr_t address, + uint32_t size, uint32_t count, uint8_t *buffer) +{ + return riscv_rw_memory(target, address, size, count, buffer, NULL); +} + +static int riscv_write_memory(struct target *target, target_addr_t address, + uint32_t size, uint32_t count, const uint8_t *buffer) +{ + return riscv_rw_memory(target, address, size, count, NULL, buffer); } static const char *riscv_get_gdb_arch(const struct target *target) diff --git a/src/target/riscv/riscv.h b/src/target/riscv/riscv.h index 77b2fdf46..0b65f5f95 100644 --- a/src/target/riscv/riscv.h +++ b/src/target/riscv/riscv.h @@ -29,6 +29,9 @@ struct riscv_program; #define RISCV_HGATP_MODE(xlen) ((xlen) == 32 ? HGATP32_MODE : HGATP64_MODE) #define RISCV_HGATP_PPN(xlen) ((xlen) == 32 ? HGATP32_PPN : HGATP64_PPN) #define RISCV_PGSHIFT 12 +#define RISCV_PGSIZE BIT(RISCV_PGSHIFT) +#define RISCV_PGBASE(addr) ((addr) & ~(RISCV_PGSIZE - 1)) +#define RISCV_PGOFFSET(addr) ((addr) & (RISCV_PGSIZE - 1)) #define PG_MAX_LEVEL 5