From: Umesh Nerlige Ramappa <umesh.nerlige.ramappa@intel.com>
To: "Dixit, Ashutosh" <ashutosh.dixit@intel.com>
Cc: intel-gfx@lists.freedesktop.org
Subject: Re: [Intel-gfx] [PATCH 16/19] drm/i915/perf: Apply Wa_18013179988
Date: Fri, 16 Sep 2022 12:04:47 -0700 [thread overview]
Message-ID: <YyTIz7UGpnCnf6ey@unerlige-ril> (raw)
In-Reply-To: <874jx7wdhb.wl-ashutosh.dixit@intel.com>
On Fri, Sep 16, 2022 at 08:22:40AM -0700, Dixit, Ashutosh wrote:
>On Thu, 15 Sep 2022 22:16:30 -0700, Dixit, Ashutosh wrote:
>>
>> On Tue, 23 Aug 2022 13:41:52 -0700, Umesh Nerlige Ramappa wrote:
>> >
>>
>> Hi Umesh,
>>
>> > OA reports in the OA buffer contain an OA timestamp field that helps
>> > user calculate delta between 2 OA reports. The calculation relies on the
>> > CS timestamp frequency to convert the timestamp value to nanoseconds.
>> > The CS timestamp frequency is a function of the CTC_SHIFT value in
>> > RPM_CONFIG0.
>> >
>> > In DG2, OA unit assumes that the CTC_SHIFT is 3, instead of using the
>> > actual value from RPM_CONFIG0. At the user level, this results in an
>> > error in calculating delta between 2 OA reports since the OA timestamp
>> > is not shifted in the same manner as CS timestamp.
>> >
>> > To resolve this, return actual OA timestamp frequency to the user in
>> > i915_getparam_ioctl.
>>
>> Rather than exposing actual OA timestamp frequency to userspace (with the
>> corresponding uapi change, specially if it's only DG2 and not all future
>> products) questions about a couple of other options:
>>
>> Option 1. Can we set CTC_SHIFT in RPM_CONFIG0 to 3, so change GT freq to be the
>> same as OA freq :-)
>>
>> The HSD seems to mention this:
>> Is setting CTC SHIFT to 0b11 on driver init an acceptable W/A?
>> Note: Changing the shift setting on live driver may break apps that are
>> currently running (including desktop manager).
>>
>> Option 2. Is it possible to correct the timestamps in OA report headers to
>> compensate for the difference between OA and GT frequencies (say when
>> copying OA data to userspace)?
>>
>> Though not sure if this is preferable to having userspace do this.
>
>Also do we need input from userland on this patch? UMD's might need to
>assess the impact of having different GT and OA frequencies at their end
>since they consume OA data?
Lionel is aware of the change and I believe he has some patches to
consume this API for the GPUvis support, but we need an Ack from
Joonas/maintainer to merge any uapi changes. I will add them to the next
revision.
Thanks,
Umesh
>
>Thanks.
>--
>Ashutosh
next prev parent reply other threads:[~2022-09-16 19:05 UTC|newest]
Thread overview: 84+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-08-23 20:41 [Intel-gfx] [PATCH 00/19] Add DG2 OA support Umesh Nerlige Ramappa
2022-08-23 20:41 ` [Intel-gfx] [PATCH 01/19] drm/i915/perf: Fix OA filtering logic for GuC mode Umesh Nerlige Ramappa
2022-09-06 14:33 ` Lionel Landwerlin
2022-09-06 17:39 ` Umesh Nerlige Ramappa
2022-09-06 18:39 ` Lionel Landwerlin
2022-09-14 22:26 ` Umesh Nerlige Ramappa
2022-09-14 23:13 ` Umesh Nerlige Ramappa
2022-09-15 22:49 ` Umesh Nerlige Ramappa
2022-09-20 3:22 ` Dixit, Ashutosh
2022-09-22 3:51 ` Dixit, Ashutosh
2022-09-22 11:05 ` Lionel Landwerlin
2022-09-09 23:47 ` Dixit, Ashutosh
2022-09-13 3:08 ` Dixit, Ashutosh
2022-09-14 23:37 ` Umesh Nerlige Ramappa
2022-09-14 23:36 ` Umesh Nerlige Ramappa
2022-09-22 3:44 ` Dixit, Ashutosh
2022-09-22 3:49 ` Dixit, Ashutosh
2022-08-23 20:41 ` [Intel-gfx] [PATCH 02/19] drm/i915/perf: Add OA formats for DG2 Umesh Nerlige Ramappa
2022-09-06 19:35 ` Lionel Landwerlin
2022-09-06 19:46 ` Umesh Nerlige Ramappa
2022-09-06 19:59 ` Lionel Landwerlin
2022-09-13 15:40 ` Dixit, Ashutosh
2022-09-14 20:54 ` Umesh Nerlige Ramappa
2022-09-14 21:16 ` Dixit, Ashutosh
2022-08-23 20:41 ` [Intel-gfx] [PATCH 03/19] drm/i915/perf: Fix noa wait predication " Umesh Nerlige Ramappa
2022-09-20 0:35 ` Dixit, Ashutosh
2022-08-23 20:41 ` [Intel-gfx] [PATCH 04/19] drm/i915/perf: Determine gen12 oa ctx offset at runtime Umesh Nerlige Ramappa
2022-09-06 19:48 ` Lionel Landwerlin
2022-09-06 20:35 ` Umesh Nerlige Ramappa
2022-09-08 18:32 ` Lionel Landwerlin
2022-09-08 23:04 ` Umesh Nerlige Ramappa
2022-08-23 20:41 ` [Intel-gfx] [PATCH 05/19] drm/i915/perf: Enable commands per clock reporting in OA Umesh Nerlige Ramappa
2022-09-06 19:51 ` Lionel Landwerlin
2022-09-14 0:19 ` Dixit, Ashutosh
2022-09-15 0:04 ` Umesh Nerlige Ramappa
2022-08-23 20:41 ` [Intel-gfx] [PATCH 06/19] drm/i915/perf: Use helpers to process reports w.r.t. OA buffer size Umesh Nerlige Ramappa
2022-09-14 16:04 ` Dixit, Ashutosh
2022-09-14 18:19 ` Umesh Nerlige Ramappa
2022-09-14 19:07 ` Dixit, Ashutosh
2022-08-23 20:41 ` [Intel-gfx] [PATCH 07/19] drm/i915/perf: Simply use stream->ctx Umesh Nerlige Ramappa
2022-09-06 19:52 ` Lionel Landwerlin
2022-08-23 20:41 ` [Intel-gfx] [PATCH 08/19] drm/i915/perf: Move gt-specific data from i915->perf to gt->perf Umesh Nerlige Ramappa
2022-09-06 19:54 ` Lionel Landwerlin
2022-09-14 18:20 ` Dixit, Ashutosh
2022-08-23 20:41 ` [Intel-gfx] [PATCH 09/19] drm/i915/perf: Replace gt->perf.lock with stream->lock for file ops Umesh Nerlige Ramappa
2022-09-14 19:04 ` Dixit, Ashutosh
2022-08-23 20:41 ` [Intel-gfx] [PATCH 10/19] drm/i915/perf: Use gt-specific ggtt for OA and noa-wait buffers Umesh Nerlige Ramappa
2022-09-06 19:56 ` Lionel Landwerlin
2022-09-06 20:28 ` Umesh Nerlige Ramappa
2022-09-06 20:31 ` Lionel Landwerlin
2022-08-23 20:41 ` [Intel-gfx] [PATCH 11/19] drm/i915/perf: Store a pointer to oa_format in oa_buffer Umesh Nerlige Ramappa
2022-09-06 19:56 ` Lionel Landwerlin
2022-09-14 20:43 ` Dixit, Ashutosh
2022-08-23 20:41 ` [Intel-gfx] [PATCH 12/19] drm/i915/perf: Parse 64bit report header formats correctly Umesh Nerlige Ramappa
2022-09-16 0:47 ` Dixit, Ashutosh
2022-08-23 20:41 ` [Intel-gfx] [PATCH 13/19] drm/i915/perf: Add Wa_16010703925:dg2 Umesh Nerlige Ramappa
2022-09-16 1:08 ` Dixit, Ashutosh
2022-08-23 20:41 ` [Intel-gfx] [PATCH 14/19] drm/i915/perf: Add Wa_1608133521:dg2 Umesh Nerlige Ramappa
2022-08-29 14:04 ` Jani Nikula
2022-09-16 1:21 ` Dixit, Ashutosh
2022-09-16 18:19 ` Umesh Nerlige Ramappa
2022-08-23 20:41 ` [Intel-gfx] [PATCH 15/19] drm/i915/perf: Add Wa_1508761755:dg2 Umesh Nerlige Ramappa
2022-09-16 1:34 ` Dixit, Ashutosh
2022-08-23 20:41 ` [Intel-gfx] [PATCH 16/19] drm/i915/perf: Apply Wa_18013179988 Umesh Nerlige Ramappa
2022-09-16 5:16 ` Dixit, Ashutosh
2022-09-16 15:22 ` Dixit, Ashutosh
2022-09-16 19:04 ` Umesh Nerlige Ramappa [this message]
2022-09-16 18:56 ` Umesh Nerlige Ramappa
2022-09-16 19:57 ` Dixit, Ashutosh
2022-09-16 20:25 ` Umesh Nerlige Ramappa
2022-09-16 21:00 ` Dixit, Ashutosh
2022-09-19 21:21 ` Umesh Nerlige Ramappa
2022-09-20 1:24 ` Dixit, Ashutosh
2022-08-23 20:41 ` [Intel-gfx] [PATCH 17/19] drm/i915/perf: Save/restore EU flex counters across reset Umesh Nerlige Ramappa
2022-09-16 5:40 ` Dixit, Ashutosh
2022-08-23 20:41 ` [Intel-gfx] [PATCH 18/19] drm/i915/guc: Support OA when Wa_16011777198 is enabled Umesh Nerlige Ramappa
2022-09-16 21:41 ` Dixit, Ashutosh
2022-09-16 21:48 ` Umesh Nerlige Ramappa
2022-08-23 20:41 ` [Intel-gfx] [PATCH 19/19] drm/i915/perf: Enable OA for DG2 Umesh Nerlige Ramappa
2022-08-23 21:11 ` [Intel-gfx] [PATCH 02/19] drm/i915/perf: Add OA formats " Umesh Nerlige Ramappa
2022-08-23 21:12 ` [Intel-gfx] [PATCH 19/19] drm/i915/perf: Enable OA " Umesh Nerlige Ramappa
2022-08-23 22:07 ` [Intel-gfx] ✗ Fi.CI.CHECKPATCH: warning for Add DG2 OA support (rev2) Patchwork
2022-08-23 22:07 ` [Intel-gfx] ✗ Fi.CI.SPARSE: " Patchwork
-- strict thread matches above, loose matches on Subject: below --
2022-08-23 0:03 [Intel-gfx] [PATCH 00/19] Add DG2 OA support Umesh Nerlige Ramappa
2022-08-23 0:03 ` [Intel-gfx] [PATCH 16/19] drm/i915/perf: Apply Wa_18013179988 Umesh Nerlige Ramappa
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=YyTIz7UGpnCnf6ey@unerlige-ril \
--to=umesh.nerlige.ramappa@intel.com \
--cc=ashutosh.dixit@intel.com \
--cc=intel-gfx@lists.freedesktop.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox