On 14.12.2023 14:33, Niklas Söderlund wrote:
> Hi Claudiu,
>
> Thanks for your work.
>
> On 2023-12-14 13:31:37 +0200, Claudiu wrote:
>> From: Claudiu Beznea <claudiu.beznea.uj@xxxxxxxxxxxxxx>
>>
>> Hardware manual specifies the following for GCCR.LTI bit:
>> 0: Setting completed
>> 1: When written: Issue a configuration request.
>> When read: Completion of settings is pending
>
> This is hard to parse at first glance, the last row have odd indentation
> and the mixing of read and write info is odd. I know this reflects how
> it's written in the datasheet, but at least there the indentation is
> correct. Also missing here is the fact that only 1 can be written to the
> bit.
>
>>
>> Thus, check the completion status when setting 1 to GCCR.LTI.
>
> Can you describe in the commit why this fix is needed. I agree it is,
> but would be nice to record why. As this have a fixes tags have you hit
> an issue? Or are you correcting the driver based on the datasheet?
Yes, this is a issue I faced while working on runtime PM support for this
driver.
>
> Maybe a more informative commit message could be to describe the change
> and why it's needed instead of the register layout?
ok
>
> The driver do not wait for the confirmation of the configuring request
> of the gPTP timer increment before moving on. Add a check to make sure
> the request completes successfully.
>
>>
>> Fixes: 7e09a052dc4e ("ravb: Exclude gPTP feature support for RZ/G2L")
>> Fixes: 568b3ce7a8ef ("ravb: factor out register bit twiddling code")
>> Fixes: 0184165b2f42 ("ravb: add sleep PM suspend/resume support")
>> Signed-off-by: Claudiu Beznea <claudiu.beznea.uj@xxxxxxxxxxxxxx>
>> ---
>> drivers/net/ethernet/renesas/ravb_main.c | 8 ++++++++
>> 1 file changed, 8 insertions(+)
>>
>> diff --git a/drivers/net/ethernet/renesas/ravb_main.c b/drivers/net/ethernet/renesas/ravb_main.c
>> index ce95eb5af354..1c253403a297 100644
>> --- a/drivers/net/ethernet/renesas/ravb_main.c
>> +++ b/drivers/net/ethernet/renesas/ravb_main.c
>> @@ -2819,6 +2819,10 @@ static int ravb_probe(struct platform_device *pdev)
>>
>> /* Request GTI loading */
>> ravb_modify(ndev, GCCR, GCCR_LTI, GCCR_LTI);
>> + /* Check completion status. */
>> + error = ravb_wait(ndev, GCCR, GCCR_LTI, 0);
>> + if (error)
>> + goto out_disable_refclk;
>
> nit: Maybe create a helper for this so future fixes only need to be
> addressed in one location?
The code intended for runtime PM support addresses this.
>
>> }
>>
>> if (info->internal_delay) {
>> @@ -3041,6 +3045,10 @@ static int __maybe_unused ravb_resume(struct device *dev)
>>
>> /* Request GTI loading */
>> ravb_modify(ndev, GCCR, GCCR_LTI, GCCR_LTI);
>> + /* Check completion status. */
>> + ret = ravb_wait(ndev, GCCR, GCCR_LTI, 0);
>> + if (ret)
>> + return ret;
>> }
>>
>> if (info->internal_delay)
>> --
>> 2.39.2
>>
>
