diff options
| -rw-r--r-- | src/target/riscv/riscv-013.c | 32 | ||||
| -rw-r--r-- | src/target/riscv/riscv.h | 1 |
2 files changed, 33 insertions, 0 deletions
diff --git a/src/target/riscv/riscv-013.c b/src/target/riscv/riscv-013.c index d256ec4..817d65f 100644 --- a/src/target/riscv/riscv-013.c +++ b/src/target/riscv/riscv-013.c @@ -759,6 +759,33 @@ static int dm_write_exec(struct target *target, uint32_t address, return dmi_write_exec(target, address + dm->base, value, ensure_success); } +static bool check_dbgbase_exists(struct target *target) +{ + uint32_t next_dm = 0; + unsigned int count = 1; + + LOG_TARGET_DEBUG(target, "Searching for DM with DMI base address (dbgbase) = 0x%x", target->dbgbase); + while (1) { + uint32_t current_dm = next_dm; + if (current_dm == target->dbgbase) + return true; + if (dmi_read(target, &next_dm, DM_NEXTDM + current_dm) != ERROR_OK) + break; + LOG_TARGET_DEBUG(target, "dm @ 0x%x --> nextdm=0x%x", current_dm, next_dm); + /* Check if it's last one in the chain. */ + if (next_dm == 0) { + LOG_TARGET_ERROR(target, "Reached the end of DM chain (detected %u DMs in total).", count); + break; + } + /* Safety: Avoid looping forever in case of buggy nextdm values in the hardware. */ + if (count++ > RISCV_MAX_DMS) { + LOG_TARGET_ERROR(target, "Supporting no more than %d DMs on a DMI bus. Aborting", RISCV_MAX_DMS); + break; + } + } + return false; +} + static int dmstatus_read_timeout(struct target *target, uint32_t *dmstatus, bool authenticated, unsigned timeout_sec) { @@ -1792,6 +1819,11 @@ static int examine(struct target *target) info->abits = get_field(dtmcontrol, DTM_DTMCS_ABITS); info->dtmcs_idle = get_field(dtmcontrol, DTM_DTMCS_IDLE); + if (!check_dbgbase_exists(target)) { + LOG_TARGET_ERROR(target, "Could not find debug module with DMI base address (dbgbase) = 0x%x", target->dbgbase); + return ERROR_FAIL; + } + /* Reset the Debug Module. */ dm013_info_t *dm = get_dm(target); if (!dm) diff --git a/src/target/riscv/riscv.h b/src/target/riscv/riscv.h index cff0d36..6afd3c1 100644 --- a/src/target/riscv/riscv.h +++ b/src/target/riscv/riscv.h @@ -19,6 +19,7 @@ struct riscv_program; #define RISCV_MAX_HARTS ((int)BIT(20)) #define RISCV_MAX_TRIGGERS 32 #define RISCV_MAX_HWBPS 16 +#define RISCV_MAX_DMS 100 #define DEFAULT_COMMAND_TIMEOUT_SEC 2 #define DEFAULT_RESET_TIMEOUT_SEC 30 |