diff options
Diffstat (limited to 'src')
| -rw-r--r-- | src/target/riscv/riscv-013.c | 126 |
1 files changed, 80 insertions, 46 deletions
diff --git a/src/target/riscv/riscv-013.c b/src/target/riscv/riscv-013.c index 183303c..2d34550 100644 --- a/src/target/riscv/riscv-013.c +++ b/src/target/riscv/riscv-013.c @@ -219,7 +219,7 @@ static riscv013_info_t *get_info(const struct target *target) return (riscv013_info_t *) info->version_specific; } -bool extension_supported(struct target *target, char letter) +bool supports_extension(struct target *target, char letter) { riscv013_info_t *info = get_info(target); unsigned num; @@ -769,43 +769,19 @@ static int abstract_write_register(struct target *target, return ERROR_OK; } -/** Actually read registers from the target right now. */ -static int register_read_direct(struct target *target, uint64_t *value, uint32_t number) +static int update_mstatus_actual(struct target *target) { - int result = abstract_read_register(target, value, number, xlen(target)); - if (result == ERROR_OK) - return result; - - // Fall back to program buffer. - if (number >= REG_FPR0 && number <= REG_FPR31) { - program_t *program = program_new(); - if (extension_supported(target, 'D')) { - program_add32(program, fmv_x_d(S0, number - REG_FPR0)); - } else { - program_add32(program, fmv_x_s(S0, number - REG_FPR0)); - } - program_add32(program, ebreak()); - program_set_read(program, S0); - execute_program(target, program); - program_delete(program); - } else if (number >= REG_CSR0 && number <= REG_CSR4095) { - program_t *program = program_new(); - program_add32(program, csrr(S0, number - REG_CSR0)); - program_add32(program, ebreak()); - program_set_read(program, S0); - execute_program(target, program); - program_delete(program); - } else { - return result; + struct reg *mstatus_reg = &target->reg_cache->reg_list[REG_MSTATUS]; + if (mstatus_reg->valid) { + // We previously made it valid. + return ERROR_OK; } - result = register_read_direct(target, value, S0); - if (result != ERROR_OK) - return result; - - LOG_DEBUG("register 0x%x = 0x%" PRIx64, number, *value); + LOG_DEBUG("Reading mstatus"); - return ERROR_OK; + // Force reading the register. In that process mstatus_actual will be + // updated. + return register_get(&target->reg_cache->reg_list[REG_MSTATUS]); } static int register_write_direct(struct target *target, unsigned number, @@ -824,8 +800,20 @@ static int register_write_direct(struct target *target, unsigned number, // Fall back to program buffer. if (number >= REG_FPR0 && number <= REG_FPR31) { + result = update_mstatus_actual(target); + if (result != ERROR_OK) { + return result; + } + if ((info->mstatus_actual & MSTATUS_FS) == 0) { + result = register_write_direct(target, REG_MSTATUS, + set_field(info->mstatus_actual, MSTATUS_FS, 1)); + if (result != ERROR_OK) + return result; + } + program_t *program = program_new(); - if (extension_supported(target, 'D')) { + // TODO: Fully support D extension on RV32. + if (supports_extension(target, 'D') && xlen(target) >= 64) { program_add32(program, fmv_d_x(number - REG_FPR0, S0)); } else { program_add32(program, fmv_s_x(number - REG_FPR0, S0)); @@ -848,6 +836,61 @@ static int register_write_direct(struct target *target, unsigned number, return result; } +/** Actually read registers from the target right now. */ +static int register_read_direct(struct target *target, uint64_t *value, uint32_t number) +{ + riscv013_info_t *info = get_info(target); + int result = abstract_read_register(target, value, number, xlen(target)); + if (result == ERROR_OK) + return result; + + // Fall back to program buffer. + if (number >= REG_FPR0 && number <= REG_FPR31) { + result = update_mstatus_actual(target); + if (result != ERROR_OK) { + return result; + } + if ((info->mstatus_actual & MSTATUS_FS) == 0) { + result = register_write_direct(target, REG_MSTATUS, + set_field(info->mstatus_actual, MSTATUS_FS, 1)); + if (result != ERROR_OK) + return result; + } + LOG_DEBUG("mstatus_actual=0x%lx", info->mstatus_actual); + + program_t *program = program_new(); + if (supports_extension(target, 'D') && xlen(target) >= 64) { + program_add32(program, fmv_x_d(S0, number - REG_FPR0)); + } else { + program_add32(program, fmv_x_s(S0, number - REG_FPR0)); + } + program_add32(program, ebreak()); + program_set_read(program, S0); + result = execute_program(target, program); + program_delete(program); + } else if (number >= REG_CSR0 && number <= REG_CSR4095) { + program_t *program = program_new(); + program_add32(program, csrr(S0, number - REG_CSR0)); + program_add32(program, ebreak()); + program_set_read(program, S0); + result = execute_program(target, program); + program_delete(program); + } else { + return result; + } + + if (result != ERROR_OK) + return result; + + result = register_read_direct(target, value, S0); + if (result != ERROR_OK) + return result; + + LOG_DEBUG("register 0x%x = 0x%" PRIx64, number, *value); + + return ERROR_OK; +} + static int maybe_read_tselect(struct target *target) { riscv013_info_t *info = get_info(target); @@ -1067,21 +1110,12 @@ static int register_write(struct target *target, unsigned int number, maybe_write_tselect(target); - if (number <= REG_XPR31) { - return abstract_write_register(target, number, xlen(target), value); - } else if (number == REG_PC) { + if (number == REG_PC) { info->dpc = value; - return ERROR_OK; - } else if (number >= REG_FPR0 && number <= REG_FPR31) { - return abstract_write_register(target, number, xlen(target), value); - } else if (number >= REG_CSR0 && number <= REG_CSR4095) { - return register_write_direct(target, number, value); } else if (number == REG_PRIV) { info->dcsr = set_field(info->dcsr, DCSR_PRV, value); - return ERROR_OK; } else { - LOG_ERROR("Don't know how to write register %d", number); - return ERROR_FAIL; + return register_write_direct(target, number, value); } return ERROR_OK; |