[PATCH v7 05/13] coresight: etm4x: exclude ss_status from drvdata->config

Leo Yan leo.yan at arm.com
Thu May 28 06:30:57 PDT 2026


On Tue, May 19, 2026 at 04:48:04PM +0100, Yeoreum Yun wrote:

[...]

> @@ -571,11 +571,11 @@ static int etm4_enable_hw(struct etmv4_drvdata *drvdata)
>  		etm4x_relaxed_write32(csa, config->res_ctrl[i], TRCRSCTLRn(i));
>  
>  	for (i = 0; i < caps->nr_ss_cmp; i++) {
> -		/* always clear status bit on restart if using single-shot */
> +		/* always clear status and pending bits on restart if using single-shot */
>  		if (config->ss_ctrl[i] || config->ss_pe_cmp[i])
> -			config->ss_status[i] &= ~TRCSSCSRn_STATUS;
> +			drvdata->ss_status[i] &= ~(TRCSSCSRn_STATUS | TRCSSCSRn_PENDING);
>  		etm4x_relaxed_write32(csa, config->ss_ctrl[i], TRCSSCCRn(i));
> -		etm4x_relaxed_write32(csa, config->ss_status[i], TRCSSCSRn(i));
> +		etm4x_relaxed_write32(csa, drvdata->ss_status[i], TRCSSCSRn(i));
>  		if (etm4x_sspcicrn_present(drvdata, i))
>  			etm4x_relaxed_write32(csa, config->ss_pe_cmp[i], TRCSSPCICRn(i));
>  	}
> @@ -772,6 +772,7 @@ static int etm4_parse_event_config(struct coresight_device *csdev,
>  	/* Clear configuration from previous run */
>  	memset(config, 0, sizeof(struct etmv4_config));
>  
> +

Unexpected new line?

> @@ -1497,8 +1498,9 @@ static void etm4_init_arch_data(void *info)
>  	 */
>  	caps->nr_ss_cmp = FIELD_GET(TRCIDR4_NUMSSCC_MASK, etmidr4);
>  	for (i = 0; i < caps->nr_ss_cmp; i++) {
> -		drvdata->config.ss_status[i] =
> -			etm4x_relaxed_read32(csa, TRCSSCSRn(i));
> +		drvdata->ss_status[i] = etm4x_relaxed_read32(csa, TRCSSCSRn(i));
> +		drvdata->ss_status[i] &= (TRCSSCSRn_PC | TRCSSCSRn_DV |
> +					  TRCSSCSRn_DA | TRCSSCSRn_INST);

Since etm4_enable_hw() clears the TRCSSCSRn_STATUS and
TRCSSCSRn_PENDING bits every time, here is no need to clear the
status bits during probe.

In the future, we may want to preserve the status within a session and
clear it only when starting a new session. Clearing the status bits here
still cannot handle stale status across multiple sessions, so we can
defer this improvement for later.

Thanks,
Leo



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