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authorDave Airlie <airlied@redhat.com>2017-09-28 05:45:27 +1000
committerDave Airlie <airlied@redhat.com>2017-09-28 05:46:15 +1000
commit29baa82aa55f40d67cfc8138c944fd8880c27e8e (patch)
tree19119a07d3ec8eb1407a68b48ec627239ee3e681 /Documentation/gpu
parente19b205be43d11bff638cad4487008c48d21c103 (diff)
parentac6c35a4d8c77083525044a192cb1a8711381e94 (diff)
downloadlinux-29baa82aa55f40d67cfc8138c944fd8880c27e8e.tar.bz2
Merge tag 'drm-misc-next-2017-09-20' of git://anongit.freedesktop.org/git/drm-misc into drm-next
UAPI Changes: Cross-subsystem Changes: Core Changes: - DP SDP defines (Ville) - polish for scdc helpers (Thierry Reding) - fix lifetimes for connector/plane state across crtc changes (Maarten Lankhorst). - sparse fixes (Ville+Thierry) - make legacy kms ioctls all interruptible (Maarten) - push edid override into the edid helpers (out of probe helpers) (Jani) - DP ESI defines for link status (DK) Driver Changes: - drm-panel is now in drm-misc! - minor panel-simple cleanups/refactoring by various folks - drm_bridge_add cleanup (Inki Dae) - constify a few i2c_device_id structs (Arvind Yadav) - More patches from Noralf's fb/gem helper cleanup - bridge/synopsis: reset fix (Philippe Cornu) - fix tracepoint include handling in drivers (Thierry) - rockchip: lvds support (Sandy Huang) - move sun4i into drm-misc fold (Maxime Ripard) - sun4i: refactor driver load + support TCON backend/layer muxing (Chen-Yu Tsai) - pl111: support more pl11x variants (Linus Walleij) - bridge/adv7511: robustify probing/edid handling (Lars-Petersen Clausen) New hw support: - S6E63J0X03 panel (Hoegeun Kwon) - OTM8009A panel (Philippe CORNU) - Seiko 43WVF1G panel (Marco Franchi) - tve200 driver (Linus Walleij) Plus assorted of tiny patches all over, including our first outreachy patches from applicants for the winter round! * tag 'drm-misc-next-2017-09-20' of git://anongit.freedesktop.org/git/drm-misc: (101 commits) drm: add backwards compatibility support for drm_kms_helper.edid_firmware drm: handle override and firmware EDID at drm_do_get_edid() level drm/dp: DPCD register defines for link status within ESI field drm/rockchip: Replace dev_* with DRM_DEV_* drm/tinydrm: Drop driver registered message drm/gem-fb-helper: Use debug message on gem lookup failure drm/imx: Use drm_gem_fb_create() and drm_gem_fb_prepare_fb() drm/bridge: adv7511: Constify HDMI CODEC platform data drm/bridge: adv7511: Enable connector polling when no interrupt is specified drm/bridge: adv7511: Remove private copy of the EDID drm/bridge: adv7511: Properly update EDID when no EDID was found drm/crtc: Convert setcrtc ioctl locking to interruptible. drm/atomic: Convert pageflip ioctl locking to interruptible. drm/legacy: Convert setplane ioctl locking to interruptible. drm/legacy: Convert cursor ioctl locking to interruptible. drm/atomic: Convert atomic ioctl locking to interruptible. drm/atomic: Prepare drm_modeset_lock infrastructure for interruptible waiting, v2. drm/tve200: Clean up panel bridging drm/doc: Update todo.rst drm/dp/mst: Sideband message transaction to power up/down nodes ...
Diffstat (limited to 'Documentation/gpu')
-rw-r--r--Documentation/gpu/drm-uapi.rst55
-rw-r--r--Documentation/gpu/index.rst1
-rw-r--r--Documentation/gpu/todo.rst26
-rw-r--r--Documentation/gpu/tve200.rst6
4 files changed, 77 insertions, 11 deletions
diff --git a/Documentation/gpu/drm-uapi.rst b/Documentation/gpu/drm-uapi.rst
index 679373b4a03f..a2214cc1f821 100644
--- a/Documentation/gpu/drm-uapi.rst
+++ b/Documentation/gpu/drm-uapi.rst
@@ -168,6 +168,61 @@ IOCTL Support on Device Nodes
.. kernel-doc:: drivers/gpu/drm/drm_ioctl.c
:doc: driver specific ioctls
+Recommended IOCTL Return Values
+-------------------------------
+
+In theory a driver's IOCTL callback is only allowed to return very few error
+codes. In practice it's good to abuse a few more. This section documents common
+practice within the DRM subsystem:
+
+ENOENT:
+ Strictly this should only be used when a file doesn't exist e.g. when
+ calling the open() syscall. We reuse that to signal any kind of object
+ lookup failure, e.g. for unknown GEM buffer object handles, unknown KMS
+ object handles and similar cases.
+
+ENOSPC:
+ Some drivers use this to differentiate "out of kernel memory" from "out
+ of VRAM". Sometimes also applies to other limited gpu resources used for
+ rendering (e.g. when you have a special limited compression buffer).
+ Sometimes resource allocation/reservation issues in command submission
+ IOCTLs are also signalled through EDEADLK.
+
+ Simply running out of kernel/system memory is signalled through ENOMEM.
+
+EPERM/EACCESS:
+ Returned for an operation that is valid, but needs more privileges.
+ E.g. root-only or much more common, DRM master-only operations return
+ this when when called by unpriviledged clients. There's no clear
+ difference between EACCESS and EPERM.
+
+ENODEV:
+ Feature (like PRIME, modesetting, GEM) is not supported by the driver.
+
+ENXIO:
+ Remote failure, either a hardware transaction (like i2c), but also used
+ when the exporting driver of a shared dma-buf or fence doesn't support a
+ feature needed.
+
+EINTR:
+ DRM drivers assume that userspace restarts all IOCTLs. Any DRM IOCTL can
+ return EINTR and in such a case should be restarted with the IOCTL
+ parameters left unchanged.
+
+EIO:
+ The GPU died and couldn't be resurrected through a reset. Modesetting
+ hardware failures are signalled through the "link status" connector
+ property.
+
+EINVAL:
+ Catch-all for anything that is an invalid argument combination which
+ cannot work.
+
+IOCTL also use other error codes like ETIME, EFAULT, EBUSY, ENOTTY but their
+usage is in line with the common meanings. The above list tries to just document
+DRM specific patterns. Note that ENOTTY has the slightly unintuitive meaning of
+"this IOCTL does not exist", and is used exactly as such in DRM.
+
.. kernel-doc:: include/drm/drm_ioctl.h
:internal:
diff --git a/Documentation/gpu/index.rst b/Documentation/gpu/index.rst
index 35d673bf9b56..c36586dad29d 100644
--- a/Documentation/gpu/index.rst
+++ b/Documentation/gpu/index.rst
@@ -15,6 +15,7 @@ Linux GPU Driver Developer's Guide
pl111
tegra
tinydrm
+ tve200
vc4
vga-switcheroo
vgaarbiter
diff --git a/Documentation/gpu/todo.rst b/Documentation/gpu/todo.rst
index 22af55d06ab8..de9512afd611 100644
--- a/Documentation/gpu/todo.rst
+++ b/Documentation/gpu/todo.rst
@@ -75,17 +75,6 @@ helpers.
Contact: Ville Syrjälä, Daniel Vetter, driver maintainers
-Implement deferred fbdev setup in the helper
---------------------------------------------
-
-Many (especially embedded drivers) want to delay fbdev setup until there's a
-real screen plugged in. This is to avoid the dreaded fallback to the low-res
-fbdev default. Many drivers have a hacked-up (and often broken) version of this,
-better to do it once in the shared helpers. Thierry has a patch series, but that
-one needs to be rebased and final polish applied.
-
-Contact: Thierry Reding, Daniel Vetter, driver maintainers
-
Convert early atomic drivers to async commit helpers
----------------------------------------------------
@@ -138,6 +127,8 @@ interfaces to fix these issues:
the acquire context explicitly on stack and then also pass it down into
drivers explicitly so that the legacy-on-atomic functions can use them.
+ Except for some driver code this is done.
+
* A bunch of the vtable hooks are now in the wrong place: DRM has a split
between core vfunc tables (named ``drm_foo_funcs``), which are used to
implement the userspace ABI. And then there's the optional hooks for the
@@ -151,6 +142,8 @@ interfaces to fix these issues:
connector at runtime. That's almost all of them, and would allow us to get
rid of a lot of ``best_encoder`` boilerplate in drivers.
+ This was almost done, but new drivers added a few more cases again.
+
Contact: Daniel Vetter
Get rid of dev->struct_mutex from GEM drivers
@@ -177,6 +170,17 @@ following drivers still use ``struct_mutex``: ``msm``, ``omapdrm`` and
Contact: Daniel Vetter, respective driver maintainers
+Convert instances of dev_info/dev_err/dev_warn to their DRM_DEV_* equivalent
+----------------------------------------------------------------------------
+
+For drivers which could have multiple instances, it is necessary to
+differentiate between which is which in the logs. Since DRM_INFO/WARN/ERROR
+don't do this, drivers used dev_info/warn/err to make this differentiation. We
+now have DRM_DEV_* variants of the drm print macros, so we can start to convert
+those drivers back to using drm-formwatted specific log messages.
+
+Contact: Sean Paul, Maintainer of the driver you plan to convert
+
Core refactorings
=================
diff --git a/Documentation/gpu/tve200.rst b/Documentation/gpu/tve200.rst
new file mode 100644
index 000000000000..69b17b324e12
--- /dev/null
+++ b/Documentation/gpu/tve200.rst
@@ -0,0 +1,6 @@
+==================================
+ drm/tve200 Faraday TV Encoder 200
+==================================
+
+.. kernel-doc:: drivers/gpu/drm/tve200/tve200_drv.c
+ :doc: Faraday TV Encoder 200