Hi Leo
A couple of minor nits below. Otherwise looks like a nice cleanup
On 01/12/2025 11:21, Leo Yan wrote:
It gives priority to TRBSR_EL1.EA (external abort); an external abort will immediately bail out and return an error.
Next, the syndrome decoding is refactored based on two levels of information: the EC (Event Class) bits and the BSC (Trace Buffer Status Code) bits.
If TRBSR_EL1.EC==0b000000, the driver continues parsing TRBSR_EL1.BSC to identify the specific trace buffer event. Otherwise, any non-zero TRBSR_EL1.EC is treated as an error.
For error cases, the driver prints an error string and dumps registers for debugging.
minor nit: Please avoid describing the code, which cod does well. Briefly mention what you are doing, giving any additional contexts that may not be evident from the code.
e.g:
"Add support for decoding the syndrome for TRBE, providing a verbose description of the code for Fatal/unhandled events. While at it add the new definitions from the latest Arm ARM for EC and BSC"
No additional checks are required for wrap mode beyond verifying the TRBSR_EL1.WRAP bit, even on units with overwrite errata, as this bit
reliably indicates a buffer wrap.
Signed-off-by: Leo Yan leo.yan@arm.com
drivers/hwtracing/coresight/coresight-trbe.c | 60 +++++++++++++++++++++------- drivers/hwtracing/coresight/coresight-trbe.h | 8 ++-- 2 files changed, 51 insertions(+), 17 deletions(-)
diff --git a/drivers/hwtracing/coresight/coresight-trbe.c b/drivers/hwtracing/coresight/coresight-trbe.c index 9e565122816949b37b8ff5e4ba04cfbc317c6f25..28e2bfa68074f19ccaa4a737d00af577aea818fe 100644 --- a/drivers/hwtracing/coresight/coresight-trbe.c +++ b/drivers/hwtracing/coresight/coresight-trbe.c @@ -643,29 +643,61 @@ static void trbe_enable_hw(struct trbe_buf *buf) static enum trbe_fault_action trbe_get_fault_act(struct perf_output_handle *handle, u64 trbsr) {
- const char *err_str; int ec = get_trbe_ec(trbsr); int bsc = get_trbe_bsc(trbsr);
- struct trbe_buf *buf = etm_perf_sink_config(handle);
- struct trbe_cpudata *cpudata = buf->cpudata;
WARN_ON(is_trbe_running(trbsr));
- if (is_trbe_trg(trbsr) || is_trbe_abort(trbsr))
return TRBE_FAULT_ACT_FATAL;
- if ((ec == TRBE_EC_STAGE1_ABORT) || (ec == TRBE_EC_STAGE2_ABORT))
return TRBE_FAULT_ACT_FATAL;
- if (is_trbe_abort(trbsr)) {
err_str = "External abort";goto out_fatal;- }
- /*
* If the trbe is affected by TRBE_WORKAROUND_OVERWRITE_FILL_MODE,* it might write data after a WRAP event in the fill mode.* Thus the check TRBPTR == TRBBASER will not be honored.*/- if ((is_trbe_wrap(trbsr) && (ec == TRBE_EC_OTHERS) && (bsc == TRBE_BSC_FILLED)) &&
(trbe_may_overwrite_in_fill_mode(cpudata) ||get_trbe_write_pointer() == get_trbe_base_pointer()))
- switch (ec) {
- case TRBE_EC_OTHERS:
break;- case TRBE_EC_BUF_MGMT_IMPL:
err_str = "Unexpected implemented management";
minor nit: "Unexpected IMPDEF buffer management event"
Suzuki
goto out_fatal;- case TRBE_EC_GP_CHECK_FAULT:
err_str = "Granule Protection Check fault";goto out_fatal;- case TRBE_EC_STAGE1_ABORT:
err_str = "Stage 1 data abort";goto out_fatal;- case TRBE_EC_STAGE2_ABORT:
err_str = "Stage 2 data abort";goto out_fatal;- default:
err_str = "Unknown error code";goto out_fatal;- }
- switch (bsc) {
- case TRBE_BSC_NOT_STOPPED:
break;- case TRBE_BSC_FILLED:
break;- case TRBE_BSC_TRIGGERED:
err_str = "Unexpected trigger status";goto out_fatal;- default:
err_str = "Unexpected buffer status code";goto out_fatal;- }
- if (is_trbe_wrap(trbsr)) return TRBE_FAULT_ACT_WRAP;
return TRBE_FAULT_ACT_SPURIOUS;
+out_fatal:
- pr_err_ratelimited("%s on CPU %d [TRBSR=0x%016llx, TRBPTR=0x%016llx, TRBLIMITR=0x%016llx]\n",
err_str, smp_processor_id(), trbsr,read_sysreg_s(SYS_TRBPTR_EL1),read_sysreg_s(SYS_TRBLIMITR_EL1));- return TRBE_FAULT_ACT_FATAL; }
static unsigned long trbe_get_trace_size(struct perf_output_handle *handle, diff --git a/drivers/hwtracing/coresight/coresight-trbe.h b/drivers/hwtracing/coresight/coresight-trbe.h index 45202c48accec7c86ba56130e2737bc2d1830fae..d7f7cd763c0c7139cf322b7336ee563073e3bea0 100644 --- a/drivers/hwtracing/coresight/coresight-trbe.h +++ b/drivers/hwtracing/coresight/coresight-trbe.h @@ -35,9 +35,11 @@ static inline bool is_trbe_enabled(void) return trblimitr & TRBLIMITR_EL1_E; } -#define TRBE_EC_OTHERS 0 -#define TRBE_EC_STAGE1_ABORT 36 -#define TRBE_EC_STAGE2_ABORT 37 +#define TRBE_EC_OTHERS 0x0 +#define TRBE_EC_GP_CHECK_FAULT 0X1e +#define TRBE_EC_BUF_MGMT_IMPL 0x1f +#define TRBE_EC_STAGE1_ABORT 0x24 +#define TRBE_EC_STAGE2_ABORT 0x25 static inline int get_trbe_ec(u64 trbsr) {