[Bug 105359] kms_frontbuffer_tracking - FBC disabled

[Bug 105359] kms_frontbuffer_tracking - FBC disabled

[bugzilla-daemon]

[-- Attachment #1.1: Type: text/plain, Size: 767 bytes --]

https://bugs.freedesktop.org/show_bug.cgi?id=105359

Marta Löfstedt <marta.lofstedt@intel.com> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
         QA Contact|intel-gfx-bugs@lists.freede |
                   |sktop.org                   |
          Component|DRM/Intel                   |IGT
           Assignee|intel-gfx-bugs@lists.freede |dri-devel@lists.freedesktop
                   |sktop.org                   |.org

--- Comment #3 from Marta Löfstedt <marta.lofstedt@intel.com> ---
Sent up an igt patch that will skip the test if FBC was disabled by previous
error.

-- 
You are receiving this mail because:
You are the assignee for the bug.

[-- Attachment #1.2: Type: text/html, Size: 2294 bytes --]

[-- Attachment #2: Type: text/plain, Size: 160 bytes --]

_______________________________________________
dri-devel mailing list
dri-devel@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/dri-devel

[Bug 105359] kms_frontbuffer_tracking - FBC disabled

[bugzilla-daemon]

[-- Attachment #1.1: Type: text/plain, Size: 1376 bytes --]

https://bugs.freedesktop.org/show_bug.cgi?id=105359

--- Comment #4 from Marta Löfstedt <marta.lofstedt@intel.com> ---
https://patchwork.freedesktop.org/patch/208170/

This caused some discussion. I appears as if devs want a way for user space to
reset the "fbc state". I am assuming this also applies for FIFO underrun caused
FBC disabled.

I guess that is OK, the only one calling:
intel_fbc_handle_fifo_underrun_irq(dev_priv);

is: 
void intel_cpu_fifo_underrun_irq_handler(struct drm_i915_private *dev_priv,
                                         enum pipe pipe)

However, this comment in above function:

        /* There's no guarantee that underrun_detected won't be set to true
         * right after this check and before the work is scheduled, but that's
         * not a problem since we'll check it again under the work function
         * while FBC is locked. This check here is just to prevent us from
         * unnecessarily scheduling the work, and it relies on the fact that we
         * never switch underrun_detect back to false after it's true. */

so maybe not totally straight forward to implement.

Also, I believe that the massive hit from "FBC disabled" on kasan and shard
testlist on BAT is due to this FBC banned by FIFO underrun thing.

-- 
You are receiving this mail because:
You are the assignee for the bug.

[-- Attachment #1.2: Type: text/html, Size: 2229 bytes --]

[-- Attachment #2: Type: text/plain, Size: 160 bytes --]

_______________________________________________
dri-devel mailing list
dri-devel@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/dri-devel

[Bug 105359] kms_frontbuffer_tracking - FBC disabled

[bugzilla-daemon]

[-- Attachment #1.1: Type: text/plain, Size: 301 bytes --]

https://bugs.freedesktop.org/show_bug.cgi?id=105359

--- Comment #5 from Marta Löfstedt <marta.lofstedt@intel.com> ---
very funny PW results on shards basically all fbc related frontbuffer_tracking
tests are skipped.

-- 
You are receiving this mail because:
You are the assignee for the bug.

[-- Attachment #1.2: Type: text/html, Size: 1072 bytes --]

[-- Attachment #2: Type: text/plain, Size: 160 bytes --]

_______________________________________________
dri-devel mailing list
dri-devel@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/dri-devel

[Bug 105359] kms_frontbuffer_tracking - FBC disabled

[bugzilla-daemon]

[-- Attachment #1.1: Type: text/plain, Size: 1177 bytes --]

https://bugs.freedesktop.org/show_bug.cgi?id=105359

--- Comment #6 from Marta Löfstedt <marta.lofstedt@intel.com> ---
I now found this to be even stranger than anticipated:

checking the i915_FBC_state while running kms tests I have ended up way to many
states for this to be sane:
After reboot:
FBC enabled
Compressing: yes

after killing lightdm:
FBC disabled: framebuffer not tiled or fenced

after running some kms tests:
FBC disabled: frontbuffer write
or
FBC disabled: no suitable CRTC for FBC
or
FBC disabled: FBC enabled (active or scheduled)
FBC worker scheduled on vblank 154675, now 154675

My recent idea was to set a warn on disabled:
+       if (strstr(buf, "FBC disabled: "))
+         {
+           igt_warn("%s\n", buf);
+           igt_assert(true);
+         }

This would result in the WARN result if FBC was disabled. This would not save
any runtime, but it should stop the confusion if the test failed due to timeout
or if due to FBC being disable.

However, when testing above on a SKL NUCi5 system I always end up with WARN on
all tests.

-- 
You are receiving this mail because:
You are the assignee for the bug.

[-- Attachment #1.2: Type: text/html, Size: 1968 bytes --]

[-- Attachment #2: Type: text/plain, Size: 160 bytes --]

_______________________________________________
dri-devel mailing list
dri-devel@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/dri-devel

[Bug 105359] kms_frontbuffer_tracking - FBC disabled

[bugzilla-daemon]

[-- Attachment #1.1: Type: text/plain, Size: 383 bytes --]

https://bugs.freedesktop.org/show_bug.cgi?id=105359

Lakshmi <lakshminarayana.vudum@intel.com> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
           Severity|normal                      |enhancement

-- 
You are receiving this mail because:
You are the assignee for the bug.

[-- Attachment #1.2: Type: text/html, Size: 1073 bytes --]

[-- Attachment #2: Type: text/plain, Size: 160 bytes --]

_______________________________________________
dri-devel mailing list
dri-devel@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/dri-devel

[Bug 105359] kms_frontbuffer_tracking - FBC disabled

[bugzilla-daemon]

[-- Attachment #1.1: Type: text/plain, Size: 572 bytes --]

https://bugs.freedesktop.org/show_bug.cgi?id=105359

Petri Latvala <petri.latvala@intel.com> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|NEW                         |RESOLVED
         Resolution|---                         |DUPLICATE

--- Comment #7 from Petri Latvala <petri.latvala@intel.com> ---


*** This bug has been marked as a duplicate of bug 108040 ***

-- 
You are receiving this mail because:
You are the assignee for the bug.

[-- Attachment #1.2: Type: text/html, Size: 2254 bytes --]

[-- Attachment #2: Type: text/plain, Size: 159 bytes --]

_______________________________________________
dri-devel mailing list
dri-devel@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/dri-devel