9 Commits

Author SHA1 Message Date
Linus Torvalds
e8bc52cb8d Driver core changes for 6.1-rc1
Here is the big set of driver core and debug printk changes for 6.1-rc1.
 Included in here is:
 	- dynamic debug updates for the core and the drm subsystem.  The
 	  drm changes have all been acked by the relevant maintainers.
 	- kernfs fixes for syzbot reported problems
 	- kernfs refactors and updates for cgroup requirements
 	- magic number cleanups and removals from the kernel tree (they
 	  were not being used and they really did not actually do
 	  anything.)
 	- other tiny cleanups
 
 All of these have been in linux-next for a while with no reported
 issues.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'driver-core-6.1-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core

Pull driver core updates from Greg KH:
 "Here is the big set of driver core and debug printk changes for
  6.1-rc1. Included in here is:

   - dynamic debug updates for the core and the drm subsystem. The drm
     changes have all been acked by the relevant maintainers

   - kernfs fixes for syzbot reported problems

   - kernfs refactors and updates for cgroup requirements

   - magic number cleanups and removals from the kernel tree (they were
     not being used and they really did not actually do anything)

   - other tiny cleanups

  All of these have been in linux-next for a while with no reported
  issues"

* tag 'driver-core-6.1-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (74 commits)
  docs: filesystems: sysfs: Make text and code for ->show() consistent
  Documentation: NBD_REQUEST_MAGIC isn't a magic number
  a.out: restore CMAGIC
  device property: Add const qualifier to device_get_match_data() parameter
  drm_print: add _ddebug descriptor to drm_*dbg prototypes
  drm_print: prefer bare printk KERN_DEBUG on generic fn
  drm_print: optimize drm_debug_enabled for jump-label
  drm-print: add drm_dbg_driver to improve namespace symmetry
  drm-print.h: include dyndbg header
  drm_print: wrap drm_*_dbg in dyndbg descriptor factory macro
  drm_print: interpose drm_*dbg with forwarding macros
  drm: POC drm on dyndbg - use in core, 2 helpers, 3 drivers.
  drm_print: condense enum drm_debug_category
  debugfs: use DEFINE_SHOW_ATTRIBUTE to define debugfs_regset32_fops
  driver core: use IS_ERR_OR_NULL() helper in device_create_groups_vargs()
  Documentation: ENI155_MAGIC isn't a magic number
  Documentation: NBD_REPLY_MAGIC isn't a magic number
  nbd: remove define-only NBD_MAGIC, previously magic number
  Documentation: FW_HEADER_MAGIC isn't a magic number
  Documentation: EEPROM_MAGIC_VALUE isn't a magic number
  ...
2022-10-07 17:04:10 -07:00
Khaled Almahallawy
7b4d8db657 drm/dp: Don't rewrite link config when setting phy test pattern
The sequence for Source DP PHY CTS automation is [2][1]:
1- Emulate successful Link Training(LT)
2- Short HPD and change link rates and number of lanes by LT.
(This is same flow for Link Layer CTS)
3- Short HPD and change PHY test pattern and swing/pre-emphasis
levels (This step should not trigger LT)

The problem is with DP PHY compliance setup as follow:

     [DPTX + on board LTTPR]------Main Link--->[Scope]
     	     	        ^                         |
			|                         |
			|                         |
			----------Aux Ch------>[Aux Emulator]

At step 3, before writing TRAINING_LANEx_SET/LINK_QUAL_PATTERN_SET
to declare the pattern/swing requested by scope, we write link
config in LINK_BW_SET/LANE_COUNT_SET on a port that has LTTPR.
As LTTPR snoops aux transaction, LINK_BW_SET/LANE_COUNT_SET writes
indicate a LT will start [Check DP 2.0 E11 -Sec 3.6.8.2 & 3.6.8.6.3],
and LTTPR will reset the link and stop sending DP signals to
DPTX/Scope causing the measurements to fail. Note that step 3 will
not trigger LT and DP link will never recovered by the
Aux Emulator/Scope.

The reset of link can be tested with a monitor connected to LTTPR
port simply by writing to LINK_BW_SET or LANE_COUNT_SET as follow

  igt/tools/dpcd_reg write --offset=0x100 --value 0x14 --device=2

OR

  printf '\x14' | sudo dd of=/dev/drm_dp_aux2 bs=1 count=1 conv=notrunc
  seek=$((0x100))

This single aux write causes the screen to blank, sending short HPD to
DPTX, setting LINK_STATUS_UPDATE = 1 in DPCD 0x204, and triggering LT.

As stated in [1]:
"Before any TX electrical testing can be performed, the link between a
DPTX and DPRX (in this case, a piece of test equipment), including all
LTTPRs within the path, shall be trained as defined in this Standard."

In addition, changing Phy pattern/Swing/Pre-emphasis (Step 3) uses the
same link rate and lane count applied on step 2, so no need to redo LT.

The fix is to not rewrite link config in step 3, and just writes
TRAINING_LANEx_SET and LINK_QUAL_PATTERN_SET

[1]: DP 2.0 E11 - 3.6.11.1 LTTPR DPTX_PHY Electrical Compliance

[2]: Configuring UnigrafDPTC Controller - Automation Test Sequence
https://www.keysight.com/us/en/assets/9922-01244/help-files/
D9040DPPC-DisplayPort-Test-Software-Online-Help-latest.chm

Cc: Imre Deak <imre.deak@intel.com>
Cc: Jani Nikula <jani.nikula@intel.com>
Cc: Or Cochvi <or.cochvi@intel.com>
Signed-off-by: Khaled Almahallawy <khaled.almahallawy@intel.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220916054900.415804-1-khaled.almahallawy@intel.com
2022-09-28 12:22:31 +03:00
Jim Cromie
f158936b60 drm: POC drm on dyndbg - use in core, 2 helpers, 3 drivers.
Use DECLARE_DYNDBG_CLASSMAP across DRM:

 - in .c files, since macro defines/initializes a record

 - in drivers, $mod_{drv,drm,param}.c
   ie where param setup is done, since a classmap is param related

 - in drm/drm_print.c
   since existing __drm_debug param is defined there,
   and we ifdef it, and provide an elaborated alternative.

 - in drm_*_helper modules:
   dp/drm_dp - 1st item in makefile target
   drivers/gpu/drm/drm_crtc_helper.c - random pick iirc.

Since these modules all use identical CLASSMAP declarations (ie: names
and .class_id's) they will all respond together to "class DRM_UT_*"
query-commands:

  :#> echo class DRM_UT_KMS +p > /proc/dynamic_debug/control

NOTES:

This changes __drm_debug from int to ulong, so BIT() is usable on it.

DRM's enum drm_debug_category values need to sync with the index of
their respective class-names here.  Then .class_id == category, and
dyndbg's class FOO mechanisms will enable drm_dbg(DRM_UT_KMS, ...).

Though DRM needs consistent categories across all modules, thats not
generally needed; modules X and Y could define FOO differently (ie a
different NAME => class_id mapping), changes are made according to
each module's private class-map.

No callsites are actually selected by this patch, since none are
class'd yet.

Signed-off-by: Jim Cromie <jim.cromie@gmail.com>
Link: https://lore.kernel.org/r/20220912052852.1123868-3-jim.cromie@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-09-24 15:02:01 +02:00
Jani Nikula
5b04aab6d4 drm/dp: add drm_dp_phy_name() for getting DP PHY name
Add a helper for getting the DP PHY name. In the interest of caller
simplicity and to avoid allocations and passing in of buffers, duplicate
the const strings to return. It's a minor penalty to pay for simplicity
in all the call sites.

v2: Rebase, add kernel-doc, ensure non-NULL always

Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/b08dc12a7e621a48ec35546d6cd1ed4b1434810d.1660553850.git.jani.nikula@intel.com
2022-08-30 11:02:42 +03:00
shaomin Deng
71eed8a9ba drm:delete the repeated word "the" in comments
remove the rebundant word "the" from comments.

Signed-off-by: shaomin Deng <dengshaomin@cdjrlc.com>
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Link: https://patchwork.freedesktop.org/patch/msgid/20220718151154.9628-1-dengshaomin@cdjrlc.com
2022-07-19 09:03:24 +02:00
Ville Syrjälä
73289afe03 drm: Remove linux/fb.h from drm_crtc.h
drm_crtc.h has no need for linux/fb.h, so don't include it.
Avoids useless rebuilds of the entire universe when
touching linux/fb.h.

Quite a few placs do currently depend on linux/fb.h or other
headers pulled in by it without actually including any of it
directly. All of those need to be fixed up.

v2: Split the vmwgfx change out

Acked-by: Sam Ravnborg <sam@ravnborg.org>
Acked-by: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220630195114.17407-3-ville.syrjala@linux.intel.com
2022-07-05 21:14:02 +03:00
Jiang Jian
e1b7234b4a drm/display: Remove duplicate 'the' in two places.
there is an unexpected word "the" in the comments that need to be dropped
file: drivers/gpu/drm/display/drm_dp_helper.c
line: 1600
  * Doesn't account the the "MOT" bit, and instead assumes each
changed to
  * Doesn't account the "MOT" bit, and instead assumes eac

Signed-off-by: Jiang Jian <jiangjian@cdjrlc.com>
Signed-off-by: Lyude Paul <lyude@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220621190055.8323-1-jiangjian@cdjrlc.com
2022-06-21 15:29:45 -04:00
Ville Syrjälä
255490f915 drm: Drop drm_edid.h from drm_crtc.h
drm_crtc.h has no need for drm_edid.h, so don't include it.
Avoids useless rebuilds of the entire universe when
touching drm_edid.h.

Quite a few placs do currently depend on drm_edid.h without
actually including it directly. All of those need to be fixed
up.

v2: Fix up i915 and msm some more
v3: Fix alphabetical ordering (Sam)

Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220614090245.30283-1-ville.syrjala@linux.intel.com
Acked-by: Sam Ravnborg <sam@ravnborg.org>
Acked-by: Jani Nikula <jani.nikula@intel.com>
2022-06-20 23:53:55 +03:00
Thomas Zimmermann
1e0f66420b drm/display: Introduce a DRM display-helper module
Replace the DP-helper module with a display-helper module. The
support for DisplayPort becomes an internal option that drivers
have to select. Update all related Kconfig and Makefile rules.

Besides the existing code for DisplayPort, the new module will
contain helpers for other video-output standards, such as HDMI.
Drivers will have to select their required video-output helpers.

Linking all display-related code into a single module avoids the
proliferation of small kernel modules.

The module parameters drm_dp_cec_unregister_delay, dp_aux_i2c_speed_khz,
and dp_aux_i2c_transfer_size are moving from the drm_dp_helper namespace
to drm_display_helper.

v2:
	* mention module parameters in commit message (Javier)
	* distiguish between display module and DP support in Kconfig
	* update Makefile rules for DP helpers
	* move Kconfig rules into separate file under display/

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Lyude Paul <lyude@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220421073108.19226-4-tzimmermann@suse.de
2022-04-25 11:19:21 +02:00