| Message ID | 20201125003108.156110-1-aditya.swarup@intel.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | drm/i915/tgl: Fix REVID macros for TGL to fetch correct stepping | expand |
Hi Aditya,
Thank you for the patch! Perhaps something to improve:
[auto build test WARNING on drm-intel/for-linux-next]
[also build test WARNING on drm-tip/drm-tip v5.10-rc5 next-20201124]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch]
url: https://github.com/0day-ci/linux/commits/Aditya-Swarup/drm-i915-tgl-Fix-REVID-macros-for-TGL-to-fetch-correct-stepping/20201125-083215
base: git://anongit.freedesktop.org/drm-intel for-linux-next
config: i386-randconfig-a004-20201125 (attached as .config)
compiler: gcc-9 (Debian 9.3.0-15) 9.3.0
reproduce (this is a W=1 build):
# https://github.com/0day-ci/linux/commit/ce4e72969ddaa07dd8426d230d04ed91382e2fd9
git remote add linux-review https://github.com/0day-ci/linux
git fetch --no-tags linux-review Aditya-Swarup/drm-i915-tgl-Fix-REVID-macros-for-TGL-to-fetch-correct-stepping/20201125-083215
git checkout ce4e72969ddaa07dd8426d230d04ed91382e2fd9
# save the attached .config to linux build tree
make W=1 ARCH=i386
If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <lkp@intel.com>
All warnings (new ones prefixed by >>):
In file included from include/drm/drm_mm.h:49,
from include/drm/drm_vma_manager.h:26,
from include/drm/drm_gem.h:40,
from drivers/gpu/drm/i915/i915_drv.h:55,
from drivers/gpu/drm/i915/gt/intel_workarounds.c:7:
drivers/gpu/drm/i915/i915_drv.h: In function 'tgl_revids_get':
>> drivers/gpu/drm/i915/i915_drv.h:1594:9: warning: format '%lu' expects argument of type 'long unsigned int', but argument 5 has type 'unsigned int' [-Wformat=]
1594 | "Unsupported SOC stepping found %u, using %lu instead\n",
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
include/drm/drm_print.h:450:38: note: in definition of macro 'drm_dbg_kms'
450 | drm_dev_dbg((drm)->dev, DRM_UT_KMS, fmt, ##__VA_ARGS__)
| ^~~
In file included from drivers/gpu/drm/i915/gt/intel_workarounds.c:7:
drivers/gpu/drm/i915/i915_drv.h:1594:53: note: format string is defined here
1594 | "Unsupported SOC stepping found %u, using %lu instead\n",
| ~~^
| |
| long unsigned int
| %u
In file included from include/drm/drm_mm.h:49,
from include/drm/drm_vma_manager.h:26,
from include/drm/drm_gem.h:40,
from drivers/gpu/drm/i915/i915_drv.h:55,
from drivers/gpu/drm/i915/gt/intel_workarounds.c:7:
drivers/gpu/drm/i915/i915_drv.h:1602:8: warning: format '%lu' expects argument of type 'long unsigned int', but argument 5 has type 'unsigned int' [-Wformat=]
1602 | "Unsupported SOC stepping found %u, using %lu instead\n",
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
include/drm/drm_print.h:450:38: note: in definition of macro 'drm_dbg_kms'
450 | drm_dev_dbg((drm)->dev, DRM_UT_KMS, fmt, ##__VA_ARGS__)
| ^~~
In file included from drivers/gpu/drm/i915/gt/intel_workarounds.c:7:
drivers/gpu/drm/i915/i915_drv.h:1602:52: note: format string is defined here
1602 | "Unsupported SOC stepping found %u, using %lu instead\n",
| ~~^
| |
| long unsigned int
| %u
vim +1594 drivers/gpu/drm/i915/i915_drv.h
1577
1578 #define TGL_UY_REVID_RANGE(revid) \
1579 ((revid) < ARRAY_SIZE(tgl_uy_revids))
1580
1581 #define TGL_REVID_RANGE(revid) \
1582 ((revid) < ARRAY_SIZE(tgl_revids))
1583
1584 static inline const struct i915_rev_steppings *
1585 tgl_revids_get(struct drm_i915_private *dev_priv)
1586 {
1587 const u8 revid = INTEL_REVID(dev_priv);
1588
1589 if (IS_TGL_U(dev_priv) || IS_TGL_Y(dev_priv)) {
1590 if (TGL_UY_REVID_RANGE(revid)) {
1591 return tgl_uy_revids + revid;
1592 } else {
1593 drm_dbg_kms(&dev_priv->drm,
> 1594 "Unsupported SOC stepping found %u, using %lu instead\n",
1595 revid, ARRAY_SIZE(tgl_uy_revids) - 1);
1596 return tgl_uy_revids + (ARRAY_SIZE(tgl_uy_revids) - 1);
1597 }
1598 } else if (TGL_REVID_RANGE(revid)) {
1599 return tgl_revids + revid;
1600 } else {
1601 drm_dbg_kms(&dev_priv->drm,
1602 "Unsupported SOC stepping found %u, using %lu instead\n",
1603 revid, ARRAY_SIZE(tgl_revids) - 1);
1604 return tgl_uy_revids + (ARRAY_SIZE(tgl_revids) - 1);
1605 }
1606 }
1607
---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org
Hi Aditya,
Thank you for the patch! Perhaps something to improve:
[auto build test WARNING on drm-intel/for-linux-next]
[also build test WARNING on drm-tip/drm-tip v5.10-rc5 next-20201124]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch]
url: https://github.com/0day-ci/linux/commits/Aditya-Swarup/drm-i915-tgl-Fix-REVID-macros-for-TGL-to-fetch-correct-stepping/20201125-083215
base: git://anongit.freedesktop.org/drm-intel for-linux-next
config: i386-randconfig-a005-20201125 (attached as .config)
compiler: gcc-9 (Debian 9.3.0-15) 9.3.0
reproduce (this is a W=1 build):
# https://github.com/0day-ci/linux/commit/ce4e72969ddaa07dd8426d230d04ed91382e2fd9
git remote add linux-review https://github.com/0day-ci/linux
git fetch --no-tags linux-review Aditya-Swarup/drm-i915-tgl-Fix-REVID-macros-for-TGL-to-fetch-correct-stepping/20201125-083215
git checkout ce4e72969ddaa07dd8426d230d04ed91382e2fd9
# save the attached .config to linux build tree
make W=1 ARCH=i386
If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <lkp@intel.com>
All warnings (new ones prefixed by >>):
In file included from include/drm/drm_mm.h:49,
from drivers/gpu/drm/i915/i915_vma.h:31,
from drivers/gpu/drm/i915/gt/uc/intel_guc.h:17,
from drivers/gpu/drm/i915/gt/uc/intel_uc.h:9,
from drivers/gpu/drm/i915/gt/intel_gt_types.h:16,
from drivers/gpu/drm/i915/gt/intel_gt.h:10,
from drivers/gpu/drm/i915/selftests/igt_reset.c:10:
drivers/gpu/drm/i915/selftests/../i915_drv.h: In function 'tgl_revids_get':
>> drivers/gpu/drm/i915/selftests/../i915_drv.h:1594:9: warning: format '%lu' expects argument of type 'long unsigned int', but argument 5 has type 'unsigned int' [-Wformat=]
1594 | "Unsupported SOC stepping found %u, using %lu instead\n",
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
include/drm/drm_print.h:450:38: note: in definition of macro 'drm_dbg_kms'
450 | drm_dev_dbg((drm)->dev, DRM_UT_KMS, fmt, ##__VA_ARGS__)
| ^~~
In file included from drivers/gpu/drm/i915/selftests/igt_reset.c:12:
drivers/gpu/drm/i915/selftests/../i915_drv.h:1594:53: note: format string is defined here
1594 | "Unsupported SOC stepping found %u, using %lu instead\n",
| ~~^
| |
| long unsigned int
| %u
In file included from include/drm/drm_mm.h:49,
from drivers/gpu/drm/i915/i915_vma.h:31,
from drivers/gpu/drm/i915/gt/uc/intel_guc.h:17,
from drivers/gpu/drm/i915/gt/uc/intel_uc.h:9,
from drivers/gpu/drm/i915/gt/intel_gt_types.h:16,
from drivers/gpu/drm/i915/gt/intel_gt.h:10,
from drivers/gpu/drm/i915/selftests/igt_reset.c:10:
drivers/gpu/drm/i915/selftests/../i915_drv.h:1602:8: warning: format '%lu' expects argument of type 'long unsigned int', but argument 5 has type 'unsigned int' [-Wformat=]
1602 | "Unsupported SOC stepping found %u, using %lu instead\n",
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
include/drm/drm_print.h:450:38: note: in definition of macro 'drm_dbg_kms'
450 | drm_dev_dbg((drm)->dev, DRM_UT_KMS, fmt, ##__VA_ARGS__)
| ^~~
In file included from drivers/gpu/drm/i915/selftests/igt_reset.c:12:
drivers/gpu/drm/i915/selftests/../i915_drv.h:1602:52: note: format string is defined here
1602 | "Unsupported SOC stepping found %u, using %lu instead\n",
| ~~^
| |
| long unsigned int
| %u
vim +1594 drivers/gpu/drm/i915/selftests/../i915_drv.h
1577
1578 #define TGL_UY_REVID_RANGE(revid) \
1579 ((revid) < ARRAY_SIZE(tgl_uy_revids))
1580
1581 #define TGL_REVID_RANGE(revid) \
1582 ((revid) < ARRAY_SIZE(tgl_revids))
1583
1584 static inline const struct i915_rev_steppings *
1585 tgl_revids_get(struct drm_i915_private *dev_priv)
1586 {
1587 const u8 revid = INTEL_REVID(dev_priv);
1588
1589 if (IS_TGL_U(dev_priv) || IS_TGL_Y(dev_priv)) {
1590 if (TGL_UY_REVID_RANGE(revid)) {
1591 return tgl_uy_revids + revid;
1592 } else {
1593 drm_dbg_kms(&dev_priv->drm,
> 1594 "Unsupported SOC stepping found %u, using %lu instead\n",
1595 revid, ARRAY_SIZE(tgl_uy_revids) - 1);
1596 return tgl_uy_revids + (ARRAY_SIZE(tgl_uy_revids) - 1);
1597 }
1598 } else if (TGL_REVID_RANGE(revid)) {
1599 return tgl_revids + revid;
1600 } else {
1601 drm_dbg_kms(&dev_priv->drm,
1602 "Unsupported SOC stepping found %u, using %lu instead\n",
1603 revid, ARRAY_SIZE(tgl_revids) - 1);
1604 return tgl_uy_revids + (ARRAY_SIZE(tgl_revids) - 1);
1605 }
1606 }
1607
---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org
On Tue, 24 Nov 2020, Aditya Swarup <aditya.swarup@intel.com> wrote: > Fix TGL REVID macros to fetch correct display/gt stepping based > on SOC rev id from INTEL_REVID() macro. Previously, we were just > returning the first element of the revid array instead of using > the correct index based on SOC rev id. > > Also, add array bound checks for TGL REV ID array. Since, there > might be a possibility of using older kernels on latest platform > revision, resulting in out of bounds access for rev ID array. > In this scenario, print message for unsupported rev ID and apply > settings for latest rev ID available. > > Fixes: ("drm/i915/tgl: Fix stepping WA matching") > Cc: José Roberto de Souza <jose.souza@intel.com> > Cc: Matt Roper <matthew.d.roper@intel.com> > Cc: Lucas De Marchi <lucas.demarchi@intel.com> > Cc: Jani Nikula <jani.nikula@intel.com> > Cc: Ville Syrjälä <ville.syrjala@linux.intel.com> > Signed-off-by: Aditya Swarup <aditya.swarup@intel.com> > --- > drivers/gpu/drm/i915/i915_drv.h | 35 +++++++++++++++++++++++++++------ > 1 file changed, 29 insertions(+), 6 deletions(-) > > diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h > index 15be8debae54..29d55b7017be 100644 > --- a/drivers/gpu/drm/i915/i915_drv.h > +++ b/drivers/gpu/drm/i915/i915_drv.h > @@ -1572,16 +1572,37 @@ enum { > TGL_REVID_D0, > }; > > -extern const struct i915_rev_steppings tgl_uy_revids[]; > -extern const struct i915_rev_steppings tgl_revids[]; > +extern const struct i915_rev_steppings tgl_uy_revids[4]; > +extern const struct i915_rev_steppings tgl_revids[2]; Just a quick note, the compiler does not check that the size in the extern declaration matches the size in the array definition. So you might end up with a mismatch without noticing. BR, Jani. > + > +#define TGL_UY_REVID_RANGE(revid) \ > + ((revid) < ARRAY_SIZE(tgl_uy_revids)) > + > +#define TGL_REVID_RANGE(revid) \ > + ((revid) < ARRAY_SIZE(tgl_revids)) > > static inline const struct i915_rev_steppings * > tgl_revids_get(struct drm_i915_private *dev_priv) > { > - if (IS_TGL_U(dev_priv) || IS_TGL_Y(dev_priv)) > - return tgl_uy_revids; > - else > - return tgl_revids; > + const u8 revid = INTEL_REVID(dev_priv); > + > + if (IS_TGL_U(dev_priv) || IS_TGL_Y(dev_priv)) { > + if (TGL_UY_REVID_RANGE(revid)) { > + return tgl_uy_revids + revid; > + } else { > + drm_dbg_kms(&dev_priv->drm, > + "Unsupported SOC stepping found %u, using %lu instead\n", > + revid, ARRAY_SIZE(tgl_uy_revids) - 1); > + return tgl_uy_revids + (ARRAY_SIZE(tgl_uy_revids) - 1); > + } > + } else if (TGL_REVID_RANGE(revid)) { > + return tgl_revids + revid; > + } else { > + drm_dbg_kms(&dev_priv->drm, > + "Unsupported SOC stepping found %u, using %lu instead\n", > + revid, ARRAY_SIZE(tgl_revids) - 1); > + return tgl_uy_revids + (ARRAY_SIZE(tgl_revids) - 1); > + } > } > > #define IS_TGL_DISP_REVID(p, since, until) \ > @@ -1591,12 +1612,14 @@ tgl_revids_get(struct drm_i915_private *dev_priv) > > #define IS_TGL_UY_GT_REVID(p, since, until) \ > ((IS_TGL_U(p) || IS_TGL_Y(p)) && \ > + TGL_UY_REVID_RANGE(INTEL_REVID(p)) && \ > tgl_uy_revids->gt_stepping >= (since) && \ > tgl_uy_revids->gt_stepping <= (until)) > > #define IS_TGL_GT_REVID(p, since, until) \ > (IS_TIGERLAKE(p) && \ > !(IS_TGL_U(p) || IS_TGL_Y(p)) && \ > + TGL_REVID_RANGE(INTEL_REVID(p)) && \ > tgl_revids->gt_stepping >= (since) && \ > tgl_revids->gt_stepping <= (until))
On Tue, 2020-11-24 at 16:31 -0800, Aditya Swarup wrote: > Fix TGL REVID macros to fetch correct display/gt stepping based > on SOC rev id from INTEL_REVID() macro. Previously, we were just > returning the first element of the revid array instead of using > the correct index based on SOC rev id. > > Also, add array bound checks for TGL REV ID array. Since, there > might be a possibility of using older kernels on latest platform > revision, resulting in out of bounds access for rev ID array. > In this scenario, print message for unsupported rev ID and apply > settings for latest rev ID available. > > Fixes: ("drm/i915/tgl: Fix stepping WA matching") > Cc: José Roberto de Souza <jose.souza@intel.com> > Cc: Matt Roper <matthew.d.roper@intel.com> > Cc: Lucas De Marchi <lucas.demarchi@intel.com> > Cc: Jani Nikula <jani.nikula@intel.com> > Cc: Ville Syrjälä <ville.syrjala@linux.intel.com> > Signed-off-by: Aditya Swarup <aditya.swarup@intel.com> > --- > drivers/gpu/drm/i915/i915_drv.h | 35 +++++++++++++++++++++++++++------ > 1 file changed, 29 insertions(+), 6 deletions(-) > > diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h > index 15be8debae54..29d55b7017be 100644 > --- a/drivers/gpu/drm/i915/i915_drv.h > +++ b/drivers/gpu/drm/i915/i915_drv.h > @@ -1572,16 +1572,37 @@ enum { > TGL_REVID_D0, > }; > > > > > > > > > -extern const struct i915_rev_steppings tgl_uy_revids[]; > -extern const struct i915_rev_steppings tgl_revids[]; > +extern const struct i915_rev_steppings tgl_uy_revids[4]; > +extern const struct i915_rev_steppings tgl_revids[2]; Not sure if the above will work, saw a comment from Jani please check that. > + > +#define TGL_UY_REVID_RANGE(revid) \ > + ((revid) < ARRAY_SIZE(tgl_uy_revids)) > + > +#define TGL_REVID_RANGE(revid) \ > + ((revid) < ARRAY_SIZE(tgl_revids)) > > > > > > > > > > > > > > > > > static inline const struct i915_rev_steppings * > tgl_revids_get(struct drm_i915_private *dev_priv) > { > - if (IS_TGL_U(dev_priv) || IS_TGL_Y(dev_priv)) > - return tgl_uy_revids; > - else > - return tgl_revids; > + const u8 revid = INTEL_REVID(dev_priv); > + > + if (IS_TGL_U(dev_priv) || IS_TGL_Y(dev_priv)) { > + if (TGL_UY_REVID_RANGE(revid)) { > + return tgl_uy_revids + revid; Why not help readers and go simple? tgl_uy_revids[revid] > + } else { > + drm_dbg_kms(&dev_priv->drm, > + "Unsupported SOC stepping found %u, using %lu instead\n", > + revid, ARRAY_SIZE(tgl_uy_revids) - 1); > + return tgl_uy_revids + (ARRAY_SIZE(tgl_uy_revids) - 1); > + } > + } else if (TGL_REVID_RANGE(revid)) { > + return tgl_revids + revid; > + } else { > + drm_dbg_kms(&dev_priv->drm, > + "Unsupported SOC stepping found %u, using %lu instead\n", > + revid, ARRAY_SIZE(tgl_revids) - 1); > + return tgl_uy_revids + (ARRAY_SIZE(tgl_revids) - 1); > + } I bet you can re arrange it and end up with one drm_dbg_kms() call. > } > > > > > > > > > #define IS_TGL_DISP_REVID(p, since, until) \ > @@ -1591,12 +1612,14 @@ tgl_revids_get(struct drm_i915_private *dev_priv) > > > > > > > > > #define IS_TGL_UY_GT_REVID(p, since, until) \ > ((IS_TGL_U(p) || IS_TGL_Y(p)) && \ > + TGL_UY_REVID_RANGE(INTEL_REVID(p)) && \ > tgl_uy_revids->gt_stepping >= (since) && \ > tgl_uy_revids->gt_stepping <= (until)) > > > > > > > > > #define IS_TGL_GT_REVID(p, since, until) \ > (IS_TIGERLAKE(p) && \ > !(IS_TGL_U(p) || IS_TGL_Y(p)) && \ > + TGL_REVID_RANGE(INTEL_REVID(p)) && \ > tgl_revids->gt_stepping >= (since) && \ > tgl_revids->gt_stepping <= (until)) > > > > > > > You did not fixed the issue for GT. > > > > >
Quoting Jani Nikula (2020-11-25 11:45:56) > On Tue, 24 Nov 2020, Aditya Swarup <aditya.swarup@intel.com> wrote: > > Fix TGL REVID macros to fetch correct display/gt stepping based > > on SOC rev id from INTEL_REVID() macro. Previously, we were just > > returning the first element of the revid array instead of using > > the correct index based on SOC rev id. > > > > Also, add array bound checks for TGL REV ID array. Since, there > > might be a possibility of using older kernels on latest platform > > revision, resulting in out of bounds access for rev ID array. > > In this scenario, print message for unsupported rev ID and apply > > settings for latest rev ID available. > > > > Fixes: ("drm/i915/tgl: Fix stepping WA matching") > > Cc: José Roberto de Souza <jose.souza@intel.com> > > Cc: Matt Roper <matthew.d.roper@intel.com> > > Cc: Lucas De Marchi <lucas.demarchi@intel.com> > > Cc: Jani Nikula <jani.nikula@intel.com> > > Cc: Ville Syrjälä <ville.syrjala@linux.intel.com> > > Signed-off-by: Aditya Swarup <aditya.swarup@intel.com> > > --- > > drivers/gpu/drm/i915/i915_drv.h | 35 +++++++++++++++++++++++++++------ > > 1 file changed, 29 insertions(+), 6 deletions(-) > > > > diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h > > index 15be8debae54..29d55b7017be 100644 > > --- a/drivers/gpu/drm/i915/i915_drv.h > > +++ b/drivers/gpu/drm/i915/i915_drv.h > > @@ -1572,16 +1572,37 @@ enum { > > TGL_REVID_D0, > > }; > > > > -extern const struct i915_rev_steppings tgl_uy_revids[]; > > -extern const struct i915_rev_steppings tgl_revids[]; > > +extern const struct i915_rev_steppings tgl_uy_revids[4]; > > +extern const struct i915_rev_steppings tgl_revids[2]; > > Just a quick note, the compiler does not check that the size in the > extern declaration matches the size in the array definition. So you > might end up with a mismatch without noticing. What surprised me is that this defeated the __must_be_array() check. I thought these were just pointers to C > > +#define TGL_UY_REVID_RANGE(revid) \ > > + ((revid) < ARRAY_SIZE(tgl_uy_revids)) > > + > > +#define TGL_REVID_RANGE(revid) \ > > + ((revid) < ARRAY_SIZE(tgl_revids)) > > > > static inline const struct i915_rev_steppings * > > tgl_revids_get(struct drm_i915_private *dev_priv) > > { > > - if (IS_TGL_U(dev_priv) || IS_TGL_Y(dev_priv)) > > - return tgl_uy_revids; > > - else > > - return tgl_revids; > > + const u8 revid = INTEL_REVID(dev_priv); > > + > > + if (IS_TGL_U(dev_priv) || IS_TGL_Y(dev_priv)) { > > + if (TGL_UY_REVID_RANGE(revid)) { > > + return tgl_uy_revids + revid; > > + } else { > > + drm_dbg_kms(&dev_priv->drm, > > + "Unsupported SOC stepping found %u, using %lu instead\n", > > + revid, ARRAY_SIZE(tgl_uy_revids) - 1); Also please don't have a dbg for every single IS_TGL_*_REVID invocation. And this is not _kms, but driver; better yet, don't bother with a drm_dbg_kms here at all. If you want to actually check, add something like intel_detect_preproduction_hw() and warn about unknown future revids. Or include the info when we print the revid in the caps. -Chris
On 11/25/20 7:33 AM, Chris Wilson wrote: > Quoting Jani Nikula (2020-11-25 11:45:56) >> On Tue, 24 Nov 2020, Aditya Swarup <aditya.swarup@intel.com> wrote: >>> Fix TGL REVID macros to fetch correct display/gt stepping based >>> on SOC rev id from INTEL_REVID() macro. Previously, we were just >>> returning the first element of the revid array instead of using >>> the correct index based on SOC rev id. >>> >>> Also, add array bound checks for TGL REV ID array. Since, there >>> might be a possibility of using older kernels on latest platform >>> revision, resulting in out of bounds access for rev ID array. >>> In this scenario, print message for unsupported rev ID and apply >>> settings for latest rev ID available. >>> >>> Fixes: ("drm/i915/tgl: Fix stepping WA matching") >>> Cc: José Roberto de Souza <jose.souza@intel.com> >>> Cc: Matt Roper <matthew.d.roper@intel.com> >>> Cc: Lucas De Marchi <lucas.demarchi@intel.com> >>> Cc: Jani Nikula <jani.nikula@intel.com> >>> Cc: Ville Syrjälä <ville.syrjala@linux.intel.com> >>> Signed-off-by: Aditya Swarup <aditya.swarup@intel.com> >>> --- >>> drivers/gpu/drm/i915/i915_drv.h | 35 +++++++++++++++++++++++++++------ >>> 1 file changed, 29 insertions(+), 6 deletions(-) >>> >>> diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h >>> index 15be8debae54..29d55b7017be 100644 >>> --- a/drivers/gpu/drm/i915/i915_drv.h >>> +++ b/drivers/gpu/drm/i915/i915_drv.h >>> @@ -1572,16 +1572,37 @@ enum { >>> TGL_REVID_D0, >>> }; >>> >>> -extern const struct i915_rev_steppings tgl_uy_revids[]; >>> -extern const struct i915_rev_steppings tgl_revids[]; >>> +extern const struct i915_rev_steppings tgl_uy_revids[4]; >>> +extern const struct i915_rev_steppings tgl_revids[2]; >> >> Just a quick note, the compiler does not check that the size in the >> extern declaration matches the size in the array definition. So you >> might end up with a mismatch without noticing. Yes.. We will have to take care of it if we are adding rev id to array table(which mostly should remain a const once we decide to go upstream). Without this declaration, I cannot use ARRAY_SIZE() macro with revid arrays as the sizeof() operator complains about not knowing the size of the array in question as it is an extern declaration. So, I don't know what other approach you want to suggest? If we move all the array tables to i915_drv.h(which I feel would be a better approach rather than having it in intel_workarounds.c), Matt Roper's KBL patch says that compiler complains about unused variables. We are anyhow going to correct the whole thing with your stepping series anyway. This is supposed to be a stop gap fix. Revids shouldn't be changing for TGL anymore. > > What surprised me is that this defeated the __must_be_array() check. > I thought these were just pointers to C > >>> +#define TGL_UY_REVID_RANGE(revid) \ >>> + ((revid) < ARRAY_SIZE(tgl_uy_revids)) >>> + >>> +#define TGL_REVID_RANGE(revid) \ >>> + ((revid) < ARRAY_SIZE(tgl_revids)) >>> >>> static inline const struct i915_rev_steppings * >>> tgl_revids_get(struct drm_i915_private *dev_priv) >>> { >>> - if (IS_TGL_U(dev_priv) || IS_TGL_Y(dev_priv)) >>> - return tgl_uy_revids; >>> - else >>> - return tgl_revids; >>> + const u8 revid = INTEL_REVID(dev_priv); >>> + >>> + if (IS_TGL_U(dev_priv) || IS_TGL_Y(dev_priv)) { >>> + if (TGL_UY_REVID_RANGE(revid)) { >>> + return tgl_uy_revids + revid; >>> + } else { >>> + drm_dbg_kms(&dev_priv->drm, >>> + "Unsupported SOC stepping found %u, using %lu instead\n", >>> + revid, ARRAY_SIZE(tgl_uy_revids) - 1); > > Also please don't have a dbg for every single IS_TGL_*_REVID > invocation. And this is not _kms, but driver; better yet, don't bother > with a drm_dbg_kms here at all. > > If you want to actually check, add something like > intel_detect_preproduction_hw() and warn about unknown future revids. > Or include the info when we print the revid in the caps. So, what you are suggesting is add an info print in that function intel_detect_preproduction_hw() right? Or something else? > -Chris >
On 11/25/20 5:21 AM, Souza, Jose wrote: > On Tue, 2020-11-24 at 16:31 -0800, Aditya Swarup wrote: >> Fix TGL REVID macros to fetch correct display/gt stepping based >> on SOC rev id from INTEL_REVID() macro. Previously, we were just >> returning the first element of the revid array instead of using >> the correct index based on SOC rev id. >> >> Also, add array bound checks for TGL REV ID array. Since, there >> might be a possibility of using older kernels on latest platform >> revision, resulting in out of bounds access for rev ID array. >> In this scenario, print message for unsupported rev ID and apply >> settings for latest rev ID available. >> >> Fixes: ("drm/i915/tgl: Fix stepping WA matching") >> Cc: José Roberto de Souza <jose.souza@intel.com> >> Cc: Matt Roper <matthew.d.roper@intel.com> >> Cc: Lucas De Marchi <lucas.demarchi@intel.com> >> Cc: Jani Nikula <jani.nikula@intel.com> >> Cc: Ville Syrjälä <ville.syrjala@linux.intel.com> >> Signed-off-by: Aditya Swarup <aditya.swarup@intel.com> >> --- >> drivers/gpu/drm/i915/i915_drv.h | 35 +++++++++++++++++++++++++++------ >> 1 file changed, 29 insertions(+), 6 deletions(-) >> >> diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h >> index 15be8debae54..29d55b7017be 100644 >> --- a/drivers/gpu/drm/i915/i915_drv.h >> +++ b/drivers/gpu/drm/i915/i915_drv.h >> @@ -1572,16 +1572,37 @@ enum { >> TGL_REVID_D0, >> }; >> >> >> >> >> >> >> >> >> -extern const struct i915_rev_steppings tgl_uy_revids[]; >> -extern const struct i915_rev_steppings tgl_revids[]; >> +extern const struct i915_rev_steppings tgl_uy_revids[4]; >> +extern const struct i915_rev_steppings tgl_revids[2]; > > Not sure if the above will work, saw a comment from Jani please check that. This works otherwise I can't use ARRAY_SIZE() macro as it is just an extern declaration, so the sizeof() doesn't have clue about the size. The only way I can think of working around this is by moving tables here but Matt's KBL REVID patch suggests unused variables errors but my compiler didn't complain. > >> + >> +#define TGL_UY_REVID_RANGE(revid) \ >> + ((revid) < ARRAY_SIZE(tgl_uy_revids)) >> + >> +#define TGL_REVID_RANGE(revid) \ >> + ((revid) < ARRAY_SIZE(tgl_revids)) >> >> >> >> >> >> >> >> >> >> >> >> >> >> >> >> >> static inline const struct i915_rev_steppings * >> tgl_revids_get(struct drm_i915_private *dev_priv) >> { >> - if (IS_TGL_U(dev_priv) || IS_TGL_Y(dev_priv)) >> - return tgl_uy_revids; >> - else >> - return tgl_revids; >> + const u8 revid = INTEL_REVID(dev_priv); >> + >> + if (IS_TGL_U(dev_priv) || IS_TGL_Y(dev_priv)) { >> + if (TGL_UY_REVID_RANGE(revid)) { >> + return tgl_uy_revids + revid; > > Why not help readers and go simple? tgl_uy_revids[revid] Hmm I will have to change the return type then, as you were returning a pointer and introduces compiler error. I will change the return type. > >> + } else { >> + drm_dbg_kms(&dev_priv->drm, >> + "Unsupported SOC stepping found %u, using %lu instead\n", >> + revid, ARRAY_SIZE(tgl_uy_revids) - 1); >> + return tgl_uy_revids + (ARRAY_SIZE(tgl_uy_revids) - 1); >> + } >> + } else if (TGL_REVID_RANGE(revid)) { >> + return tgl_revids + revid; >> + } else { >> + drm_dbg_kms(&dev_priv->drm, >> + "Unsupported SOC stepping found %u, using %lu instead\n", >> + revid, ARRAY_SIZE(tgl_revids) - 1); >> + return tgl_uy_revids + (ARRAY_SIZE(tgl_revids) - 1); >> + } > > I bet you can re arrange it and end up with one drm_dbg_kms() call. I can but that will involve more macros as we are dealing with two different array tables and each one with a different range. I will use just one print to say what SOC rev id we get from pci dev and what we will be using. > > >> } >> >> >> >> >> >> >> >> >> #define IS_TGL_DISP_REVID(p, since, until) \ >> @@ -1591,12 +1612,14 @@ tgl_revids_get(struct drm_i915_private *dev_priv) >> >> >> >> >> >> >> >> >> #define IS_TGL_UY_GT_REVID(p, since, until) \ >> ((IS_TGL_U(p) || IS_TGL_Y(p)) && \ >> + TGL_UY_REVID_RANGE(INTEL_REVID(p)) && \ >> tgl_uy_revids->gt_stepping >= (since) && \ >> tgl_uy_revids->gt_stepping <= (until)) >> >> >> >> >> >> >> >> >> #define IS_TGL_GT_REVID(p, since, until) \ >> (IS_TIGERLAKE(p) && \ >> !(IS_TGL_U(p) || IS_TGL_Y(p)) && \ >> + TGL_REVID_RANGE(INTEL_REVID(p)) && \ >> tgl_revids->gt_stepping >= (since) && \ >> tgl_revids->gt_stepping <= (until)) >> >> >> >> >> >> >> > > You did not fixed the issue for GT. Yes.. I didn't notice that.. Will change in the next revision. Aditya > >> >> >> >> >> >
On Wed, 2020-11-25 at 10:03 -0800, Aditya Swarup wrote: > On 11/25/20 5:21 AM, Souza, Jose wrote: > > On Tue, 2020-11-24 at 16:31 -0800, Aditya Swarup wrote: > > > Fix TGL REVID macros to fetch correct display/gt stepping based > > > on SOC rev id from INTEL_REVID() macro. Previously, we were just > > > returning the first element of the revid array instead of using > > > the correct index based on SOC rev id. > > > > > > Also, add array bound checks for TGL REV ID array. Since, there > > > might be a possibility of using older kernels on latest platform > > > revision, resulting in out of bounds access for rev ID array. > > > In this scenario, print message for unsupported rev ID and apply > > > settings for latest rev ID available. > > > > > > Fixes: ("drm/i915/tgl: Fix stepping WA matching") > > > Cc: José Roberto de Souza <jose.souza@intel.com> > > > Cc: Matt Roper <matthew.d.roper@intel.com> > > > Cc: Lucas De Marchi <lucas.demarchi@intel.com> > > > Cc: Jani Nikula <jani.nikula@intel.com> > > > Cc: Ville Syrjälä <ville.syrjala@linux.intel.com> > > > Signed-off-by: Aditya Swarup <aditya.swarup@intel.com> > > > --- > > > drivers/gpu/drm/i915/i915_drv.h | 35 +++++++++++++++++++++++++++------ > > > 1 file changed, 29 insertions(+), 6 deletions(-) > > > > > > diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h > > > index 15be8debae54..29d55b7017be 100644 > > > --- a/drivers/gpu/drm/i915/i915_drv.h > > > +++ b/drivers/gpu/drm/i915/i915_drv.h > > > @@ -1572,16 +1572,37 @@ enum { > > > TGL_REVID_D0, > > > }; > > > > > > > > > > > > > > > > > > > > > > > > > > > -extern const struct i915_rev_steppings tgl_uy_revids[]; > > > -extern const struct i915_rev_steppings tgl_revids[]; > > > +extern const struct i915_rev_steppings tgl_uy_revids[4]; > > > +extern const struct i915_rev_steppings tgl_revids[2]; > > > > Not sure if the above will work, saw a comment from Jani please check that. > > This works otherwise I can't use ARRAY_SIZE() macro as it is just an extern declaration, > so the sizeof() doesn't have clue about the size. The only way I can think of working > around this is by moving tables here but Matt's KBL REVID patch suggests unused variables errors > but my compiler didn't complain. > > > > > > + > > > +#define TGL_UY_REVID_RANGE(revid) \ > > > + ((revid) < ARRAY_SIZE(tgl_uy_revids)) > > > + > > > +#define TGL_REVID_RANGE(revid) \ > > > + ((revid) < ARRAY_SIZE(tgl_revids)) > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > static inline const struct i915_rev_steppings * > > > tgl_revids_get(struct drm_i915_private *dev_priv) > > > { > > > - if (IS_TGL_U(dev_priv) || IS_TGL_Y(dev_priv)) > > > - return tgl_uy_revids; > > > - else > > > - return tgl_revids; > > > + const u8 revid = INTEL_REVID(dev_priv); > > > + > > > + if (IS_TGL_U(dev_priv) || IS_TGL_Y(dev_priv)) { > > > + if (TGL_UY_REVID_RANGE(revid)) { > > > + return tgl_uy_revids + revid; > > > > Why not help readers and go simple? tgl_uy_revids[revid] > > Hmm I will have to change the return type then, as you were returning a pointer and introduces > compiler error. I will change the return type. No need to change the return type. &tgl_uy_revids[revid] > > > > > > + } else { > > > + drm_dbg_kms(&dev_priv->drm, > > > + "Unsupported SOC stepping found %u, using %lu instead\n", > > > + revid, ARRAY_SIZE(tgl_uy_revids) - 1); > > > + return tgl_uy_revids + (ARRAY_SIZE(tgl_uy_revids) - 1); > > > + } > > > + } else if (TGL_REVID_RANGE(revid)) { > > > + return tgl_revids + revid; > > > + } else { > > > + drm_dbg_kms(&dev_priv->drm, > > > + "Unsupported SOC stepping found %u, using %lu instead\n", > > > + revid, ARRAY_SIZE(tgl_revids) - 1); > > > + return tgl_uy_revids + (ARRAY_SIZE(tgl_revids) - 1); > > > + } > > > > I bet you can re arrange it and end up with one drm_dbg_kms() call. > > I can but that will involve more macros as we are dealing with two different array tables and each one > with a different range. I will use just one print to say what SOC rev id we get from pci dev and what > we will be using. > > > > > > > > } > > > > > > > > > > > > > > > > > > > > > > > > > > > #define IS_TGL_DISP_REVID(p, since, until) \ > > > @@ -1591,12 +1612,14 @@ tgl_revids_get(struct drm_i915_private *dev_priv) > > > > > > > > > > > > > > > > > > > > > > > > > > > #define IS_TGL_UY_GT_REVID(p, since, until) \ > > > ((IS_TGL_U(p) || IS_TGL_Y(p)) && \ > > > + TGL_UY_REVID_RANGE(INTEL_REVID(p)) && \ > > > tgl_uy_revids->gt_stepping >= (since) && \ > > > tgl_uy_revids->gt_stepping <= (until)) > > > > > > > > > > > > > > > > > > > > > > > > > > > #define IS_TGL_GT_REVID(p, since, until) \ > > > (IS_TIGERLAKE(p) && \ > > > !(IS_TGL_U(p) || IS_TGL_Y(p)) && \ > > > + TGL_REVID_RANGE(INTEL_REVID(p)) && \ > > > tgl_revids->gt_stepping >= (since) && \ > > > tgl_revids->gt_stepping <= (until)) > > > > > > > > > > > > > > > > > > > > > > > > > You did not fixed the issue for GT. > > Yes.. I didn't notice that.. Will change in the next revision. > > Aditya > > > > > > > > > > > > > > > > > > > > >
On Wed, Nov 25, 2020 at 09:51:04AM -0800, Aditya Swarup wrote: > On 11/25/20 7:33 AM, Chris Wilson wrote: > > Quoting Jani Nikula (2020-11-25 11:45:56) > >> On Tue, 24 Nov 2020, Aditya Swarup <aditya.swarup@intel.com> wrote: > >>> Fix TGL REVID macros to fetch correct display/gt stepping based > >>> on SOC rev id from INTEL_REVID() macro. Previously, we were just > >>> returning the first element of the revid array instead of using > >>> the correct index based on SOC rev id. > >>> > >>> Also, add array bound checks for TGL REV ID array. Since, there > >>> might be a possibility of using older kernels on latest platform > >>> revision, resulting in out of bounds access for rev ID array. > >>> In this scenario, print message for unsupported rev ID and apply > >>> settings for latest rev ID available. > >>> > >>> Fixes: ("drm/i915/tgl: Fix stepping WA matching") > >>> Cc: José Roberto de Souza <jose.souza@intel.com> > >>> Cc: Matt Roper <matthew.d.roper@intel.com> > >>> Cc: Lucas De Marchi <lucas.demarchi@intel.com> > >>> Cc: Jani Nikula <jani.nikula@intel.com> > >>> Cc: Ville Syrjälä <ville.syrjala@linux.intel.com> > >>> Signed-off-by: Aditya Swarup <aditya.swarup@intel.com> > >>> --- > >>> drivers/gpu/drm/i915/i915_drv.h | 35 +++++++++++++++++++++++++++------ > >>> 1 file changed, 29 insertions(+), 6 deletions(-) > >>> > >>> diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h > >>> index 15be8debae54..29d55b7017be 100644 > >>> --- a/drivers/gpu/drm/i915/i915_drv.h > >>> +++ b/drivers/gpu/drm/i915/i915_drv.h > >>> @@ -1572,16 +1572,37 @@ enum { > >>> TGL_REVID_D0, > >>> }; > >>> > >>> -extern const struct i915_rev_steppings tgl_uy_revids[]; > >>> -extern const struct i915_rev_steppings tgl_revids[]; > >>> +extern const struct i915_rev_steppings tgl_uy_revids[4]; > >>> +extern const struct i915_rev_steppings tgl_revids[2]; > >> > >> Just a quick note, the compiler does not check that the size in the > >> extern declaration matches the size in the array definition. So you > >> might end up with a mismatch without noticing. > > Yes.. We will have to take care of it if we are adding rev id to array table(which mostly > should remain a const once we decide to go upstream). Without this declaration, I cannot > use ARRAY_SIZE() macro with revid arrays as the sizeof() operator complains about not > knowing the size of the array in question as it is an extern declaration. Can't you replace the ARRAY_SIZE() with a sentinel? I guess Making it a struct with a size member would be another option.
On Wed, Nov 25, 2020 at 03:33:23PM +0000, Chris Wilson wrote: >Quoting Jani Nikula (2020-11-25 11:45:56) >> On Tue, 24 Nov 2020, Aditya Swarup <aditya.swarup@intel.com> wrote: >> > Fix TGL REVID macros to fetch correct display/gt stepping based >> > on SOC rev id from INTEL_REVID() macro. Previously, we were just >> > returning the first element of the revid array instead of using >> > the correct index based on SOC rev id. >> > >> > Also, add array bound checks for TGL REV ID array. Since, there >> > might be a possibility of using older kernels on latest platform >> > revision, resulting in out of bounds access for rev ID array. >> > In this scenario, print message for unsupported rev ID and apply >> > settings for latest rev ID available. >> > >> > Fixes: ("drm/i915/tgl: Fix stepping WA matching") >> > Cc: José Roberto de Souza <jose.souza@intel.com> >> > Cc: Matt Roper <matthew.d.roper@intel.com> >> > Cc: Lucas De Marchi <lucas.demarchi@intel.com> >> > Cc: Jani Nikula <jani.nikula@intel.com> >> > Cc: Ville Syrjälä <ville.syrjala@linux.intel.com> >> > Signed-off-by: Aditya Swarup <aditya.swarup@intel.com> >> > --- >> > drivers/gpu/drm/i915/i915_drv.h | 35 +++++++++++++++++++++++++++------ >> > 1 file changed, 29 insertions(+), 6 deletions(-) >> > >> > diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h >> > index 15be8debae54..29d55b7017be 100644 >> > --- a/drivers/gpu/drm/i915/i915_drv.h >> > +++ b/drivers/gpu/drm/i915/i915_drv.h >> > @@ -1572,16 +1572,37 @@ enum { >> > TGL_REVID_D0, >> > }; >> > >> > -extern const struct i915_rev_steppings tgl_uy_revids[]; >> > -extern const struct i915_rev_steppings tgl_revids[]; >> > +extern const struct i915_rev_steppings tgl_uy_revids[4]; >> > +extern const struct i915_rev_steppings tgl_revids[2]; >> >> Just a quick note, the compiler does not check that the size in the >> extern declaration matches the size in the array definition. So you >> might end up with a mismatch without noticing. > >What surprised me is that this defeated the __must_be_array() check. >I thought these were just pointers to C it doesn't complain because it actually works. The extern is declaring that amount of storage size... I think people here are confusing with accepting an array as a parameter, in which case it decays to a pointer. Since this is all obscure semantics of C, for the quick fix here maybe better to just define the size and reuse it both in header and .c? and then work in the refactor that will actually remove all of this. Lucas De Marchi > >> > +#define TGL_UY_REVID_RANGE(revid) \ >> > + ((revid) < ARRAY_SIZE(tgl_uy_revids)) >> > + >> > +#define TGL_REVID_RANGE(revid) \ >> > + ((revid) < ARRAY_SIZE(tgl_revids)) >> > >> > static inline const struct i915_rev_steppings * >> > tgl_revids_get(struct drm_i915_private *dev_priv) >> > { >> > - if (IS_TGL_U(dev_priv) || IS_TGL_Y(dev_priv)) >> > - return tgl_uy_revids; >> > - else >> > - return tgl_revids; >> > + const u8 revid = INTEL_REVID(dev_priv); >> > + >> > + if (IS_TGL_U(dev_priv) || IS_TGL_Y(dev_priv)) { >> > + if (TGL_UY_REVID_RANGE(revid)) { >> > + return tgl_uy_revids + revid; >> > + } else { >> > + drm_dbg_kms(&dev_priv->drm, >> > + "Unsupported SOC stepping found %u, using %lu instead\n", >> > + revid, ARRAY_SIZE(tgl_uy_revids) - 1); > >Also please don't have a dbg for every single IS_TGL_*_REVID >invocation. And this is not _kms, but driver; better yet, don't bother >with a drm_dbg_kms here at all. > >If you want to actually check, add something like >intel_detect_preproduction_hw() and warn about unknown future revids. >Or include the info when we print the revid in the caps. >-Chris
On Wed, Nov 25, 2020 at 09:51:04AM -0800, Aditya Swarup wrote: >On 11/25/20 7:33 AM, Chris Wilson wrote: >> Quoting Jani Nikula (2020-11-25 11:45:56) >>> On Tue, 24 Nov 2020, Aditya Swarup <aditya.swarup@intel.com> wrote: >>>> Fix TGL REVID macros to fetch correct display/gt stepping based >>>> on SOC rev id from INTEL_REVID() macro. Previously, we were just >>>> returning the first element of the revid array instead of using >>>> the correct index based on SOC rev id. >>>> >>>> Also, add array bound checks for TGL REV ID array. Since, there >>>> might be a possibility of using older kernels on latest platform >>>> revision, resulting in out of bounds access for rev ID array. >>>> In this scenario, print message for unsupported rev ID and apply >>>> settings for latest rev ID available. >>>> >>>> Fixes: ("drm/i915/tgl: Fix stepping WA matching") >>>> Cc: José Roberto de Souza <jose.souza@intel.com> >>>> Cc: Matt Roper <matthew.d.roper@intel.com> >>>> Cc: Lucas De Marchi <lucas.demarchi@intel.com> >>>> Cc: Jani Nikula <jani.nikula@intel.com> >>>> Cc: Ville Syrjälä <ville.syrjala@linux.intel.com> >>>> Signed-off-by: Aditya Swarup <aditya.swarup@intel.com> >>>> --- >>>> drivers/gpu/drm/i915/i915_drv.h | 35 +++++++++++++++++++++++++++------ >>>> 1 file changed, 29 insertions(+), 6 deletions(-) >>>> >>>> diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h >>>> index 15be8debae54..29d55b7017be 100644 >>>> --- a/drivers/gpu/drm/i915/i915_drv.h >>>> +++ b/drivers/gpu/drm/i915/i915_drv.h >>>> @@ -1572,16 +1572,37 @@ enum { >>>> TGL_REVID_D0, >>>> }; >>>> >>>> -extern const struct i915_rev_steppings tgl_uy_revids[]; >>>> -extern const struct i915_rev_steppings tgl_revids[]; >>>> +extern const struct i915_rev_steppings tgl_uy_revids[4]; >>>> +extern const struct i915_rev_steppings tgl_revids[2]; >>> >>> Just a quick note, the compiler does not check that the size in the >>> extern declaration matches the size in the array definition. So you >>> might end up with a mismatch without noticing. > >Yes.. We will have to take care of it if we are adding rev id to array table(which mostly >should remain a const once we decide to go upstream). Without this declaration, I cannot >use ARRAY_SIZE() macro with revid arrays as the sizeof() operator complains about not >knowing the size of the array in question as it is an extern declaration. > >So, I don't know what other approach you want to suggest? If we move all the array tables to i915_drv.h(which >I feel would be a better approach rather than having it in intel_workarounds.c), Matt >Roper's KBL patch says that compiler complains about unused variables. adding the table in the header means that each compilation unit (.o) will get a copy of the table when it includes the header (it will end up being trimmed out if not used though). This is not what you want. As I said in the other reply, sizeof does actually work here: $ cat /tmp/a.c #include <stdio.h> #include "b.h" int main(int argc, const char *argv[]) { printf("%zu", sizeof(tgl_uy_revids)); return 0; } $ cat /tmp/b.h #pragma once struct i915_rev_steppings { int a; }; extern const struct i915_rev_steppings tgl_uy_revids[4]; $ cat /tmp/b.c #include "b.h" const struct i915_rev_steppings tgl_uy_revids[] = { { 10 }, { 20 }, { 30 }, { 40 }, }; And compiler also warns if in the *definition* of tgl_uy_revids it goes over the amount of space of the declaration. For clarity, you may however want to add a define to tell the size: -extern const struct i915_rev_steppings tgl_uy_revids[4]; +#define TGL_UY_REVIDS_SIZE 4 +extern const struct i915_rev_steppings tgl_uy_revids[TGL_UY_REVIDS_SIZE]; and do the same in the .c > >We are anyhow going to correct the whole thing with your stepping series anyway. This is supposed >to be a stop gap fix. Revids shouldn't be changing for TGL anymore. > >> >> What surprised me is that this defeated the __must_be_array() check. >> I thought these were just pointers to C >> >>>> +#define TGL_UY_REVID_RANGE(revid) \ >>>> + ((revid) < ARRAY_SIZE(tgl_uy_revids)) >>>> + >>>> +#define TGL_REVID_RANGE(revid) \ >>>> + ((revid) < ARRAY_SIZE(tgl_revids)) >>>> >>>> static inline const struct i915_rev_steppings * >>>> tgl_revids_get(struct drm_i915_private *dev_priv) >>>> { >>>> - if (IS_TGL_U(dev_priv) || IS_TGL_Y(dev_priv)) >>>> - return tgl_uy_revids; >>>> - else >>>> - return tgl_revids; >>>> + const u8 revid = INTEL_REVID(dev_priv); >>>> + >>>> + if (IS_TGL_U(dev_priv) || IS_TGL_Y(dev_priv)) { >>>> + if (TGL_UY_REVID_RANGE(revid)) { >>>> + return tgl_uy_revids + revid; >>>> + } else { >>>> + drm_dbg_kms(&dev_priv->drm, >>>> + "Unsupported SOC stepping found %u, using %lu instead\n", >>>> + revid, ARRAY_SIZE(tgl_uy_revids) - 1); >> >> Also please don't have a dbg for every single IS_TGL_*_REVID >> invocation. And this is not _kms, but driver; better yet, don't bother >> with a drm_dbg_kms here at all. >> >> If you want to actually check, add something like >> intel_detect_preproduction_hw() and warn about unknown future revids. >> Or include the info when we print the revid in the caps. > >So, what you are suggesting is add an info print in that function intel_detect_preproduction_hw() right? >Or something else? > >> -Chris >> >
On Wed, Nov 25, 2020 at 09:51:04AM -0800, Aditya Swarup wrote: >On 11/25/20 7:33 AM, Chris Wilson wrote: >> Quoting Jani Nikula (2020-11-25 11:45:56) >>> On Tue, 24 Nov 2020, Aditya Swarup <aditya.swarup@intel.com> wrote: >>>> + if (IS_TGL_U(dev_priv) || IS_TGL_Y(dev_priv)) { >>>> + if (TGL_UY_REVID_RANGE(revid)) { >>>> + return tgl_uy_revids + revid; >>>> + } else { >>>> + drm_dbg_kms(&dev_priv->drm, >>>> + "Unsupported SOC stepping found %u, using %lu instead\n", >>>> + revid, ARRAY_SIZE(tgl_uy_revids) - 1); >> >> Also please don't have a dbg for every single IS_TGL_*_REVID >> invocation. And this is not _kms, but driver; better yet, don't bother >> with a drm_dbg_kms here at all. >> >> If you want to actually check, add something like >> intel_detect_preproduction_hw() and warn about unknown future revids. >> Or include the info when we print the revid in the caps. > >So, what you are suggesting is add an info print in that function intel_detect_preproduction_hw() right? >Or something else? since this is all going away soon, just removing the dbg would be ok And in that case, just doing something like below would be shorter and clearer IMO (untested): if (IS_TGL_U(dev_priv) || IS_TGL_Y(dev_priv)) { arr = tgl_uy_revids; size = ARRAY_SIZE(tgl_uy_revids); } else { arr = tgl_revids; size = ARRAY_SIZE(tgl_revids); } revid = min(revid, size - 1); return &arr[revid]; That may also be 2 patches: one adding the revid so we actually apply the correct workarounds (this needs the "Fixes" tag) and the other to add the bounds check. Lucas De Marchi > >> -Chris >> >
On 11/25/20 11:18 AM, Lucas De Marchi wrote: > On Wed, Nov 25, 2020 at 09:51:04AM -0800, Aditya Swarup wrote: >> On 11/25/20 7:33 AM, Chris Wilson wrote: >>> Quoting Jani Nikula (2020-11-25 11:45:56) >>>> On Tue, 24 Nov 2020, Aditya Swarup <aditya.swarup@intel.com> wrote: >>>>> Fix TGL REVID macros to fetch correct display/gt stepping based >>>>> on SOC rev id from INTEL_REVID() macro. Previously, we were just >>>>> returning the first element of the revid array instead of using >>>>> the correct index based on SOC rev id. >>>>> >>>>> Also, add array bound checks for TGL REV ID array. Since, there >>>>> might be a possibility of using older kernels on latest platform >>>>> revision, resulting in out of bounds access for rev ID array. >>>>> In this scenario, print message for unsupported rev ID and apply >>>>> settings for latest rev ID available. >>>>> >>>>> Fixes: ("drm/i915/tgl: Fix stepping WA matching") >>>>> Cc: José Roberto de Souza <jose.souza@intel.com> >>>>> Cc: Matt Roper <matthew.d.roper@intel.com> >>>>> Cc: Lucas De Marchi <lucas.demarchi@intel.com> >>>>> Cc: Jani Nikula <jani.nikula@intel.com> >>>>> Cc: Ville Syrjälä <ville.syrjala@linux.intel.com> >>>>> Signed-off-by: Aditya Swarup <aditya.swarup@intel.com> >>>>> --- >>>>> drivers/gpu/drm/i915/i915_drv.h | 35 +++++++++++++++++++++++++++------ >>>>> 1 file changed, 29 insertions(+), 6 deletions(-) >>>>> >>>>> diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h >>>>> index 15be8debae54..29d55b7017be 100644 >>>>> --- a/drivers/gpu/drm/i915/i915_drv.h >>>>> +++ b/drivers/gpu/drm/i915/i915_drv.h >>>>> @@ -1572,16 +1572,37 @@ enum { >>>>> TGL_REVID_D0, >>>>> }; >>>>> >>>>> -extern const struct i915_rev_steppings tgl_uy_revids[]; >>>>> -extern const struct i915_rev_steppings tgl_revids[]; >>>>> +extern const struct i915_rev_steppings tgl_uy_revids[4]; >>>>> +extern const struct i915_rev_steppings tgl_revids[2]; >>>> >>>> Just a quick note, the compiler does not check that the size in the >>>> extern declaration matches the size in the array definition. So you >>>> might end up with a mismatch without noticing. >> >> Yes.. We will have to take care of it if we are adding rev id to array table(which mostly >> should remain a const once we decide to go upstream). Without this declaration, I cannot >> use ARRAY_SIZE() macro with revid arrays as the sizeof() operator complains about not >> knowing the size of the array in question as it is an extern declaration. >> >> So, I don't know what other approach you want to suggest? If we move all the array tables to i915_drv.h(which >> I feel would be a better approach rather than having it in intel_workarounds.c), Matt >> Roper's KBL patch says that compiler complains about unused variables. > > adding the table in the header means that each compilation unit (.o) > will get a copy of the table when it includes the header (it will end up > being trimmed out if not used though). This is not what you want. > > As I said in the other reply, sizeof does actually work here: The question is not about sizeof() not working but rather the usage of ARRAY_SIZE() macro in i915_drv.h with just extern declaration without size specified. > > $ cat /tmp/a.c > #include <stdio.h> > > #include "b.h" > > int main(int argc, const char *argv[]) > { > printf("%zu", sizeof(tgl_uy_revids)); > return 0; > } > > $ cat /tmp/b.h > #pragma once > > struct i915_rev_steppings { int a; }; > extern const struct i915_rev_steppings tgl_uy_revids[4]; You are specifying the size in the extern declaration which will make the ARRAY_SIZE() macro work if used in the header else it will complain. > > $ cat /tmp/b.c > #include "b.h" > > const struct i915_rev_steppings tgl_uy_revids[] = { > { 10 }, > { 20 }, > { 30 }, > { 40 }, > }; > > And compiler also warns if in the *definition* of tgl_uy_revids it goes > over the amount of space of the declaration. For clarity, you may > however want to add a define to tell the size: > > > -extern const struct i915_rev_steppings tgl_uy_revids[4]; > +#define TGL_UY_REVIDS_SIZE 4 > +extern const struct i915_rev_steppings tgl_uy_revids[TGL_UY_REVIDS_SIZE]; > > and do the same in the .c I will go ahead with this approach. Aditya > >> >> We are anyhow going to correct the whole thing with your stepping series anyway. This is supposed >> to be a stop gap fix. Revids shouldn't be changing for TGL anymore. >> >>> >>> What surprised me is that this defeated the __must_be_array() check. >>> I thought these were just pointers to C >>> >>>>> +#define TGL_UY_REVID_RANGE(revid) \ >>>>> + ((revid) < ARRAY_SIZE(tgl_uy_revids)) >>>>> + >>>>> +#define TGL_REVID_RANGE(revid) \ >>>>> + ((revid) < ARRAY_SIZE(tgl_revids)) >>>>> >>>>> static inline const struct i915_rev_steppings * >>>>> tgl_revids_get(struct drm_i915_private *dev_priv) >>>>> { >>>>> - if (IS_TGL_U(dev_priv) || IS_TGL_Y(dev_priv)) >>>>> - return tgl_uy_revids; >>>>> - else >>>>> - return tgl_revids; >>>>> + const u8 revid = INTEL_REVID(dev_priv); >>>>> + >>>>> + if (IS_TGL_U(dev_priv) || IS_TGL_Y(dev_priv)) { >>>>> + if (TGL_UY_REVID_RANGE(revid)) { >>>>> + return tgl_uy_revids + revid; >>>>> + } else { >>>>> + drm_dbg_kms(&dev_priv->drm, >>>>> + "Unsupported SOC stepping found %u, using %lu instead\n", >>>>> + revid, ARRAY_SIZE(tgl_uy_revids) - 1); >>> >>> Also please don't have a dbg for every single IS_TGL_*_REVID >>> invocation. And this is not _kms, but driver; better yet, don't bother >>> with a drm_dbg_kms here at all. >>> >>> If you want to actually check, add something like >>> intel_detect_preproduction_hw() and warn about unknown future revids. >>> Or include the info when we print the revid in the caps. >> >> So, what you are suggesting is add an info print in that function intel_detect_preproduction_hw() right? >> Or something else? >> >>> -Chris >>> >>
On 11/25/20 11:29 AM, Lucas De Marchi wrote: > On Wed, Nov 25, 2020 at 09:51:04AM -0800, Aditya Swarup wrote: >> On 11/25/20 7:33 AM, Chris Wilson wrote: >>> Quoting Jani Nikula (2020-11-25 11:45:56) >>>> On Tue, 24 Nov 2020, Aditya Swarup <aditya.swarup@intel.com> wrote: >>>>> + if (IS_TGL_U(dev_priv) || IS_TGL_Y(dev_priv)) { >>>>> + if (TGL_UY_REVID_RANGE(revid)) { >>>>> + return tgl_uy_revids + revid; >>>>> + } else { >>>>> + drm_dbg_kms(&dev_priv->drm, >>>>> + "Unsupported SOC stepping found %u, using %lu instead\n", >>>>> + revid, ARRAY_SIZE(tgl_uy_revids) - 1); >>> >>> Also please don't have a dbg for every single IS_TGL_*_REVID >>> invocation. And this is not _kms, but driver; better yet, don't bother >>> with a drm_dbg_kms here at all. >>> >>> If you want to actually check, add something like >>> intel_detect_preproduction_hw() and warn about unknown future revids. >>> Or include the info when we print the revid in the caps. >> >> So, what you are suggesting is add an info print in that function intel_detect_preproduction_hw() right? >> Or something else? > > since this is all going away soon, just removing the dbg would be ok > > And in that case, just doing something like below would be shorter and > clearer IMO (untested): > > if (IS_TGL_U(dev_priv) || IS_TGL_Y(dev_priv)) { > arr = tgl_uy_revids; > size = ARRAY_SIZE(tgl_uy_revids); > } else { > arr = tgl_revids; > size = ARRAY_SIZE(tgl_revids); > } > > revid = min(revid, size - 1); > > return &arr[revid]; > > That may also be 2 patches: one adding the revid so we actually apply > the correct workarounds (this needs the "Fixes" tag) and the other to > add the bounds check. Thanks for the suggestion. I will implement it this way. Aditya > > Lucas De Marchi > >> >>> -Chris >>> >>
On Wed, Nov 25, 2020 at 11:30:44AM -0800, Aditya Swarup wrote: >> As I said in the other reply, sizeof does actually work here: > >The question is not about sizeof() not working but rather the usage of ARRAY_SIZE() >macro in i915_drv.h with just extern declaration without size specified. ARRAY_SIZE() is just sizeof(arr)/sizeof(*arr) with additional shenanigans to check for misuse: when used with a pointer rather than an array: int b[0]; int *a = b; or void foo(int a[10]) In these cases ARRAY_SIZE(a) will not do what you expect and the macro warns about it, because sizeof(a) will be sizeof(int *) instead of the array size. > >> >> $ cat /tmp/a.c >> #include <stdio.h> >> >> #include "b.h" >> >> int main(int argc, const char *argv[]) >> { >> printf("%zu", sizeof(tgl_uy_revids)); >> return 0; >> } >> >> $ cat /tmp/b.h >> #pragma once >> >> struct i915_rev_steppings { int a; }; >> extern const struct i915_rev_steppings tgl_uy_revids[4]; > >You are specifying the size in the extern declaration which will make the ARRAY_SIZE() >macro work if used in the header else it will complain. as it should Lucas De Marchi
Quoting Aditya Swarup (2020-11-25 17:51:04) > On 11/25/20 7:33 AM, Chris Wilson wrote: > > Quoting Jani Nikula (2020-11-25 11:45:56) > >> On Tue, 24 Nov 2020, Aditya Swarup <aditya.swarup@intel.com> wrote: > >>> static inline const struct i915_rev_steppings * > >>> tgl_revids_get(struct drm_i915_private *dev_priv) > >>> { > >>> - if (IS_TGL_U(dev_priv) || IS_TGL_Y(dev_priv)) > >>> - return tgl_uy_revids; > >>> - else > >>> - return tgl_revids; > >>> + const u8 revid = INTEL_REVID(dev_priv); > >>> + > >>> + if (IS_TGL_U(dev_priv) || IS_TGL_Y(dev_priv)) { > >>> + if (TGL_UY_REVID_RANGE(revid)) { > >>> + return tgl_uy_revids + revid; > >>> + } else { > >>> + drm_dbg_kms(&dev_priv->drm, > >>> + "Unsupported SOC stepping found %u, using %lu instead\n", > >>> + revid, ARRAY_SIZE(tgl_uy_revids) - 1); > > > > Also please don't have a dbg for every single IS_TGL_*_REVID > > invocation. And this is not _kms, but driver; better yet, don't bother > > with a drm_dbg_kms here at all. > > > > If you want to actually check, add something like > > intel_detect_preproduction_hw() and warn about unknown future revids. > > Or include the info when we print the revid in the caps. > > So, what you are suggesting is add an info print in that function intel_detect_preproduction_hw() right? > Or something else? I wouldn't put it in detect_preproduction, just using that as an example of when we do probes for unexpected revids. E.g., diff --git a/drivers/gpu/drm/i915/i915_drv.c b/drivers/gpu/drm/i915/i915_drv.c index ca16ea541ecc..f1ff5509c23a 100644 --- a/drivers/gpu/drm/i915/i915_drv.c +++ b/drivers/gpu/drm/i915/i915_drv.c @@ -273,6 +273,21 @@ static void intel_detect_preproduction_hw(struct drm_i915_private *dev_priv) } } +/* + * HW that is more recent than the kernel runs the risk of us applying + * stale and disruptive w/a. Leave a debug tell-tale just in case. + */ +static void intel_detect_unknown_hw(struct drm_i915_private *dev_priv) +{ + bool post = false; + + if (post) { + drm_dbg(&dev_priv->drm, + "This machine is more recent than the w/a database!\n"); + add_taint(TAINT_MACHINE_CHECK, LOCKDEP_STILL_OK); + } +} + static void sanitize_gpu(struct drm_i915_private *i915) { if (!INTEL_INFO(i915)->gpu_reset_clobbers_display) @@ -343,6 +358,7 @@ static int i915_driver_early_probe(struct drm_i915_private *dev_priv) intel_init_audio_hooks(dev_priv); intel_detect_preproduction_hw(dev_priv); + intel_detect_unknown_hw(dev_priv); return 0; The taint is probably not justified in this case. -Chris
diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h index 15be8debae54..29d55b7017be 100644 --- a/drivers/gpu/drm/i915/i915_drv.h +++ b/drivers/gpu/drm/i915/i915_drv.h @@ -1572,16 +1572,37 @@ enum { TGL_REVID_D0, }; -extern const struct i915_rev_steppings tgl_uy_revids[]; -extern const struct i915_rev_steppings tgl_revids[]; +extern const struct i915_rev_steppings tgl_uy_revids[4]; +extern const struct i915_rev_steppings tgl_revids[2]; + +#define TGL_UY_REVID_RANGE(revid) \ + ((revid) < ARRAY_SIZE(tgl_uy_revids)) + +#define TGL_REVID_RANGE(revid) \ + ((revid) < ARRAY_SIZE(tgl_revids)) static inline const struct i915_rev_steppings * tgl_revids_get(struct drm_i915_private *dev_priv) { - if (IS_TGL_U(dev_priv) || IS_TGL_Y(dev_priv)) - return tgl_uy_revids; - else - return tgl_revids; + const u8 revid = INTEL_REVID(dev_priv); + + if (IS_TGL_U(dev_priv) || IS_TGL_Y(dev_priv)) { + if (TGL_UY_REVID_RANGE(revid)) { + return tgl_uy_revids + revid; + } else { + drm_dbg_kms(&dev_priv->drm, + "Unsupported SOC stepping found %u, using %lu instead\n", + revid, ARRAY_SIZE(tgl_uy_revids) - 1); + return tgl_uy_revids + (ARRAY_SIZE(tgl_uy_revids) - 1); + } + } else if (TGL_REVID_RANGE(revid)) { + return tgl_revids + revid; + } else { + drm_dbg_kms(&dev_priv->drm, + "Unsupported SOC stepping found %u, using %lu instead\n", + revid, ARRAY_SIZE(tgl_revids) - 1); + return tgl_uy_revids + (ARRAY_SIZE(tgl_revids) - 1); + } } #define IS_TGL_DISP_REVID(p, since, until) \ @@ -1591,12 +1612,14 @@ tgl_revids_get(struct drm_i915_private *dev_priv) #define IS_TGL_UY_GT_REVID(p, since, until) \ ((IS_TGL_U(p) || IS_TGL_Y(p)) && \ + TGL_UY_REVID_RANGE(INTEL_REVID(p)) && \ tgl_uy_revids->gt_stepping >= (since) && \ tgl_uy_revids->gt_stepping <= (until)) #define IS_TGL_GT_REVID(p, since, until) \ (IS_TIGERLAKE(p) && \ !(IS_TGL_U(p) || IS_TGL_Y(p)) && \ + TGL_REVID_RANGE(INTEL_REVID(p)) && \ tgl_revids->gt_stepping >= (since) && \ tgl_revids->gt_stepping <= (until))
Fix TGL REVID macros to fetch correct display/gt stepping based on SOC rev id from INTEL_REVID() macro. Previously, we were just returning the first element of the revid array instead of using the correct index based on SOC rev id. Also, add array bound checks for TGL REV ID array. Since, there might be a possibility of using older kernels on latest platform revision, resulting in out of bounds access for rev ID array. In this scenario, print message for unsupported rev ID and apply settings for latest rev ID available. Fixes: ("drm/i915/tgl: Fix stepping WA matching") Cc: José Roberto de Souza <jose.souza@intel.com> Cc: Matt Roper <matthew.d.roper@intel.com> Cc: Lucas De Marchi <lucas.demarchi@intel.com> Cc: Jani Nikula <jani.nikula@intel.com> Cc: Ville Syrjälä <ville.syrjala@linux.intel.com> Signed-off-by: Aditya Swarup <aditya.swarup@intel.com> --- drivers/gpu/drm/i915/i915_drv.h | 35 +++++++++++++++++++++++++++------ 1 file changed, 29 insertions(+), 6 deletions(-)