Hi James,
On Thu, Dec 09, 2021 at 11:13:55AM +0000, James Clark wrote:
On 09/12/2021 11:00, Suzuki K Poulose wrote:
On 08/12/2021 16:09, James Clark wrote:
Maintain consistency with the other options by failing to open when they aren't supported. For example ETM_OPT_TS, ETM_OPT_CTXTID2 and the newly added ETM_OPT_BRANCH_BROADCAST all return with -EINVAL if they are requested but not supported by hardware.
The consequence of not doing this is that the user may not be aware that they are not enabling the feature as it is silently disabled.
Signed-off-by: James Clark james.clark@arm.com
drivers/hwtracing/coresight/coresight-etm4x-core.c | 13 +++++++++---- 1 file changed, 9 insertions(+), 4 deletions(-)
diff --git a/drivers/hwtracing/coresight/coresight-etm4x-core.c b/drivers/hwtracing/coresight/coresight-etm4x-core.c index d2bafb50c66a..0a9bb943a5e5 100644 --- a/drivers/hwtracing/coresight/coresight-etm4x-core.c +++ b/drivers/hwtracing/coresight/coresight-etm4x-core.c @@ -674,10 +674,15 @@ static int etm4_parse_event_config(struct coresight_device *csdev, } /* return stack - enable if selected and supported */ - if ((attr->config & BIT(ETM_OPT_RETSTK)) && drvdata->retstack) - /* bit[12], Return stack enable bit */ - config->cfg |= BIT(12);
+ if (attr->config & BIT(ETM_OPT_RETSTK)) { + if (!drvdata->retstack) { + ret = -EINVAL; + goto out; + } else { + /* bit[12], Return stack enable bit */ + config->cfg |= BIT(12); + }
nit: While at this, please could you change the hard coded value to ETM4_CFG_BIT_RETSTK ?
I started changing them all because I had trouble searching for bits by name but then I thought it would snowball into a bigger change so I undid it.
I think I'll just go and do it now if it's an issue here.
I can apply this set right away and you send another patch to fix all hard coded bitfields or you can send another revision with all 4 patches included in it (bitfields fix plus these 3). Just let me know what you want to do. And next time please add a cover letter.
Thanks, Mathieu
Otherwise, looks good to me
Suzuki