Drop a few indirections, making the code simpler.
This also drops a RATELIMITED variant that is not in use.
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200214175919.GA14492@ravnborg.org
I don't understand what the DispID CEA data block revision
means. The spec doesn't say. I guess some DispID must have
a value of >= 3 in there or else we generally wouldn't
even parse the CEA data blocks. Or does all this code
actually not do anything?
Cc: Andres Rodriguez <andresx7@gmail.com>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200124200231.10517-6-ville.syrjala@linux.intel.com
Reviewed-by: Andres Rodriguez <andresx7@gmail.com>
Reviewed-by: Uma Shankar <uma.shankar@intel.com>
After much head scratching I managed to convince myself that
for_each_displayid_db() has already done the bounds checks for
the DispID CEA data block. Which is why we don't need to repeat
them in cea_db_offsets(). To avoid having to go through that
pain again in the future add a comment which explains this fact.
Cc: Andres Rodriguez <andresx7@gmail.com>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200124200231.10517-5-ville.syrjala@linux.intel.com
Acked-by: Alex Deucher <alexander.deucher@amd.com>
Reviewed-by: Uma Shankar <uma.shankar@intel.com>
Let's introduce is_detailed_timing_descritor() as the opposite
counterpart of is_display_descriptor().
Cc: Allen Chen <allen.chen@ite.com.tw>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200124200231.10517-3-ville.syrjala@linux.intel.com
Acked-by: Alex Deucher <alexander.deucher@amd.com>
Reviewed-by: Uma Shankar <uma.shankar@intel.com>
Currently we assume any 18 byte descriptor to be a display descritor
if only the tag byte matches the expected value. But for detailed
timing descriptors that same byte is just the lower 8 bits of
hblank, and as such can match any display descriptor tag. To
properly validate that the 18 byte descriptor is in fact a
display descriptor we must also examine bytes 0-2 (just byte 1
should actually suffice but the spec does say that bytes 0 and
2 must also always be zero for display descriptors so we check
those too).
Unlike Allen's original proposed patch to just fix is_rb() we
roll this out across the board to fix everything.
Cc: Allen Chen <allen.chen@ite.com.tw>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200124200231.10517-2-ville.syrjala@linux.intel.com
Acked-by: Alex Deucher <alexander.deucher@amd.com>
Reviewed-by: Uma Shankar <uma.shankar@intel.com>
CEA-861 says :
"d = offset for the byte following the reserved data block.
If no data is provided in the reserved data block, then d=4.
If no DTDs are provided, then d=0."
So let's not look for DTDs when d==0. In fact let's just make that
<4 since those values would just mean that he DTDs overlap the block
header. And let's also check that d isn't so big as to declare
the descriptors to live past the block end, although the code
does already survive that case as we'd just end up with a negative
number of descriptors and the loop would not do anything.
Cc: Allen Chen <allen.chen@ite.com.tw>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200124200231.10517-1-ville.syrjala@linux.intel.com
Acked-by: Alex Deucher <alexander.deucher@amd.com>
Reviewed-by: Uma Shankar <uma.shankar@intel.com>
We want to go over to the new lowercase ones, encourage that a bit
more.
v2: Remove the accidentally included hunk from some WIP branch this
was based on (Jani&Sam).
Cc: Jani Nikula <jani.nikula@intel.com>
Acked-by: Jani Nikula <jani.nikula@intel.com>
Reviewed-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200214090428.2929833-1-daniel.vetter@ffwll.ch
The driver currently uses runtime PM to perform some of the module
initialization and cleanup. This has three problems:
1) There is no Kconfig dependency on CONFIG_PM, so if runtime PM is
disabled, the driver will not work at all, since the module will
never be initialized.
2) The driver does not ensure that the device is suspended when
sun6i_dsi_probe() fails or when sun6i_dsi_remove() is called. It
simply disables runtime PM. From the docs of pm_runtime_disable():
The device can be either active or suspended after its runtime PM
has been disabled.
And indeed, the device will likely still be active if sun6i_dsi_probe
fails. For example, if the panel driver is not yet loaded, we have
the following sequence:
sun6i_dsi_probe()
pm_runtime_enable()
mipi_dsi_host_register()
of_mipi_dsi_device_add(child)
...device_add()...
__device_attach()
pm_runtime_get_sync(dev->parent) -> Causes resume
bus_for_each_drv()
__device_attach_driver() -> No match for panel
pm_runtime_put(dev->parent) -> Async idle request
component_add()
__component_add()
try_to_bring_up_masters()
try_to_bring_up_master()
sun4i_drv_bind()
component_bind_all()
component_bind()
sun6i_dsi_bind() -> Fails with -EPROBE_DEFER
mipi_dsi_host_unregister()
pm_runtime_disable()
__pm_runtime_disable()
__pm_runtime_barrier() -> Idle request is still pending
cancel_work_sync() -> DSI host is *not* suspended!
Since the device is not suspended, the clock and regulator are never
disabled. The imbalance causes a WARN at devres free time.
3) The driver relies on being suspended when sun6i_dsi_encoder_enable()
is called. The resume callback has a comment that says:
Some part of it can only be done once we get a number of
lanes, see sun6i_dsi_inst_init
And then part of the resume callback only runs if dsi->device is not
NULL (that is, if sun6i_dsi_attach() has been called). However, as
the above call graph shows, the resume callback is guaranteed to be
called before sun6i_dsi_attach(); it is called before child devices
get their drivers attached.
Therefore, part of the controller initialization will only run if the
device is suspended between the calls to mipi_dsi_host_register() and
component_add() (which ends up calling sun6i_dsi_encoder_enable()).
Again, as shown by the above call graph, this is not the case. It
appears that the controller happens to work because it is still
initialized by the bootloader.
Because the connector is hardcoded to always be connected, the
device's runtime PM reference is not dropped until system suspend,
when sun4i_drv_drm_sys_suspend() ends up calling
sun6i_dsi_encoder_disable(). However, that is done as a system sleep
PM hook, and at that point the system PM core has already taken
another runtime PM reference, so sun6i_dsi_runtime_suspend() is
not called. Likewise, by the time the PM core releases its reference,
sun4i_drv_drm_sys_resume() has already re-enabled the encoder.
So after system suspend and resume, we have *still never called*
sun6i_dsi_inst_init(), and now that the rest of the display pipeline
has been reset, the DSI host is unable to communicate with the panel,
causing VBLANK timeouts.
Fix all of these issues by inlining the runtime PM hooks into the
encoder enable/disable functions, which are guaranteed to run after a
panel is attached. This allows sun6i_dsi_inst_init() to be called
unconditionally. Furthermore, this causes the hardware to be turned off
during system suspend and reinitialized on resume, which was not
happening before.
Fixes: 133add5b5a ("drm/sun4i: Add Allwinner A31 MIPI-DSI controller support")
Signed-off-by: Samuel Holland <samuel@sholland.org>
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Link: https://patchwork.freedesktop.org/patch/msgid/20200211072858.30784-4-samuel@sholland.org
Currently, the DSI host blocks binding the display pipeline until the
panel is available. This unnecessarily prevents other display outpus
from working, and adds logspam to dmesg when the panel driver is built
as a module (the component master is unsuccessfully brought up several
times during boot).
Flip the dependency, instead requiring the host to be bound before the
panel is attached. The panel driver provides no functionality outside of
the display pipeline anyway.
Since the panel is now probed after the DRM connector, we need a hotplug
event to turn on the connector after the panel is attached.
This has the added benefit of fixing panel module removal/insertion.
Previously, the panel would be turned off when its module was removed.
But because the connector state was hardcoded, nothing knew to turn the
panel back on when it was re-attached. Now, with hotplug events
available, the connector state will follow the panel module state, and
the panel will be re-enabled properly.
Fixes: 133add5b5a ("drm/sun4i: Add Allwinner A31 MIPI-DSI controller support")
Signed-off-by: Samuel Holland <samuel@sholland.org>
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Link: https://patchwork.freedesktop.org/patch/msgid/20200211072858.30784-3-samuel@sholland.org
The continued use of an ERR_PTR to signify "no panel" outside of
sun6i_dsi_attach is confusing because it is a double negative. Because
the connector always reports itself as connected, there is also the
possibility of sending an ERR_PTR to drm_panel_get_modes(), which would
crash.
Solve both of these by only storing the panel pointer if it is valid.
Fixes: 133add5b5a ("drm/sun4i: Add Allwinner A31 MIPI-DSI controller support")
Signed-off-by: Samuel Holland <samuel@sholland.org>
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Link: https://patchwork.freedesktop.org/patch/msgid/20200211072858.30784-2-samuel@sholland.org
The >= compare op must happen in cpu byte order, doing it in
little endian fails on big endian machines like s390.
Reported-by: Sebastian Mitterle <smitterl@redhat.com>
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20200214080100.1273-1-kraxel@redhat.com
Unlike DP 1.2 edid corruption test, DP 1.4 requires to calculate
real CRC value of the last edid data block, and write it back.
Current edid CRC calculates routine adds the last CRC byte,
and check if non-zero.
This behavior is not accurate; actually, we need to return
the actual CRC value when corruption is detected.
This commit changes this issue by returning the calculated CRC,
and initiate the required sequence.
Change since v7
- Fix for CI.CHECKPATCH
Change since v6
- Add return check
Change since v5
- Obtain real CRC value before dumping bad edid
Change since v4
- Fix for CI.CHECKPATCH
Change since v3
- Fix a minor typo.
Change since v2
- Rewrite checksum computation routine to avoid duplicated code.
- Rename to avoid confusion.
Change since v1
- Have separate routine for returning real CRC.
Signed-off-by: Jerry (Fangzhi) Zuo <Jerry.Zuo@amd.com>
Reviewed-by: Harry Wentland <harry.wentland@amd.com>
Reviewed-by: Rodrigo Siqueira <Rodrigo.Siqueira@amd.com>
Signed-off-by: Rodrigo Siqueira <rodrigosiqueiramelo@gmail.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200211160832.24259-1-Jerry.Zuo@amd.com
The legacy version of get_scanout_position() was only useful while
drivers still used drm_driver.get_scanout_position(). With no such
drivers left, the related typedef and code can be removed
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200123135943.24140-23-tzimmermann@suse.de
All non-legacy users of VBLANK functions in struct drm_driver have been
converted to use the respective interfaces in struct drm_crtc_funcs. The
remaining users of VBLANK callbacks in struct drm_driver are legacy drivers
with userspace modesetting.
All users of struct drm_driver.get_scanout_position() have been
converted to the respective CRTC helper function. Remove the callback
from struct drm_driver.
There are no users left of get_vblank_timestamp(), so the callback is
being removed. The other VBLANK callbacks are being moved to the legacy
section at the end of struct drm_driver.
Also removed is drm_calc_vbltimestamp_from_scanoutpos(). Callers of this
function have been converted to use the CRTC instead.
v4:
* more readable code for setting high_prec (Ville, Jani)
v2:
* merge with removal of struct drm_driver.get_scanout_position()
* remove drm_calc_vbltimestamp_from_scanoutpos()
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Tested-by: Yannick Fertré <yannick.fertre@st.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200123135943.24140-22-tzimmermann@suse.de
VBLANK callbacks in struct drm_driver are deprecated in favor of
their equivalents in struct drm_crtc_funcs. Convert vmwgfx over.
v2:
* remove accidental whitespace fixes
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Acked-by: Thomas Hellstrom <thellstrom@vmware.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200123135943.24140-21-tzimmermann@suse.de
VBLANK callbacks in struct drm_driver are deprecated in favor of
their equivalents in struct drm_crtc_funcs. Convert vkms over.
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Rodrigo Siqueira <rodrigosiqueira@gmail.com>
Tested-by: Rodrigo Siqueira <rodrigosiqueira@gmail.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200123135943.24140-20-tzimmermann@suse.de
VBLANK callbacks in struct drm_driver are deprecated in favor of
their equivalents in struct drm_crtc_funcs. Convert sti over.
v2:
* remove unnecessary include of sti_crtc.h from sti_drv.c
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Acked-by: Benjamin Gaignard <benjamin.gaignard@linaro.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20200123135943.24140-17-tzimmermann@suse.de
VBLANK callbacks in struct drm_driver are deprecated in favor of
their equivalents in struct drm_crtc_funcs. Convert stm over.
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Tested-by: Yannick Fertré <yannick.fertre@st.com>
Acked-by: Philippe Cornu <philippe.cornu@st.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200123135943.24140-16-tzimmermann@suse.de
The callback struct drm_driver.get_scanout_position() is deprecated in
favor of struct drm_crtc_helper_funcs.get_scanout_position(). Convert stm
over.
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Acked-by: Philippe Cornu <philippe.cornu@st.com>
Tested-by: Yannick Fertré <yannick.fertre@st.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200123135943.24140-15-tzimmermann@suse.de
VBLANK callbacks in struct drm_driver are deprecated in favor of
their equivalents in struct drm_crtc_funcs. Convert msm over.
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Tested-by: Yannick Fertré <yannick.fertre@st.com>
Acked-by: Rob Clark <robdclark@gmail.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200123135943.24140-14-tzimmermann@suse.de
The callback struct drm_driver.get_scanout_position() is deprecated in
favor of struct drm_crtc_helper_funcs.get_scanout_position(). Convert
radeon over.
v4:
* 80-character line fixes
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200123135943.24140-11-tzimmermann@suse.de
VBLANK callbacks in struct drm_driver are deprecated in favor of
their equivalents in struct drm_crtc_funcs. Convert nouvean over.
v4:
* add argument names in function declaration
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200123135943.24140-10-tzimmermann@suse.de
The callback struct drm_driver.get_scanout_position() is deprecated in
favor of struct drm_crtc_helper_funcs.get_scanout_position(). Convert
nouveau over.
v4:
* add argument names in function declaration
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Ben Skeggs <bskeggs@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200123135943.24140-9-tzimmermann@suse.de
VBLANK callbacks in struct drm_driver are deprecated in favor of their
equivalents in struct drm_crtc_funcs. Convert i915 over.
The callback struct drm_driver.get_scanout_position() is deprecated
in favor of struct drm_crtc_helper_funcs.get_scanout_position().
i915 doesn't use CRTC helpers. Instead pass i915's implementation of
get_scanout_position() to DRM core's
drm_crtc_vblank_helper_get_vblank_timestamp_internal().
v3:
* rename dcrtc to _crtc
* use intel_ prefix for i915_crtc_get_vblank_timestamp()
* update for drm_crtc_vblank_helper_get_vblank_timestamp_internal()
v2:
* use DRM's implementation of get_vblank_timestamp()
* simplify function names
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Acked-by: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200123135943.24140-8-tzimmermann@suse.de
VBLANK callbacks in struct drm_driver are deprecated in favor of
their equivalents in struct drm_crtc_funcs. Convert amdgpu over.
v2:
* don't wrap existing functions; change signature instead
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200123135943.24140-6-tzimmermann@suse.de
The callback struct drm_driver.get_scanout_position() is deprecated in
favor of struct drm_crtc_helper_funcs.get_scanout_position(). Convert
amdgpu over.
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200123135943.24140-5-tzimmermann@suse.de
The callback get_vblank_timestamp() is currently located in struct
drm_driver, but really belongs into struct drm_crtc_funcs. Add an
equivalent there. Driver will be converted in separate patches.
The default implementation is drm_calc_vbltimestamp_from_scanoutpos().
The patch adds drm_crtc_vblank_helper_get_vblank_timestamp(), which is
an implementation for the CRTC callback.
v4:
* more readable code for setting high_prec (Ville, Jani)
v3:
* use refactored timestamp calculation to minimize duplicated code
* do more checks for crtc != NULL to support legacy drivers
v2:
* rename helper to drm_crtc_vblank_helper_get_vblank_timestamp()
* replace drm_calc_vbltimestamp_from_scanoutpos() with
drm_crtc_vblank_helper_get_vblank_timestamp() in docs
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200123135943.24140-4-tzimmermann@suse.de
The new callback get_scanout_position() reads the current location
of the scanout process. The operation is currently located in struct
drm_driver, but really belongs to the CRTC. Drivers will be converted
in separate patches.
To help with the conversion, the timestamp calculation has been
moved from drm_calc_vbltimestamp_from_scanoutpos() to
drm_crtc_vblank_helper_get_vblank_timestamp_internal(). The helper
function supports the new and old interface of get_scanout_position().
drm_calc_vbltimestamp_from_scanoutpos() remains as a wrapper around
the new function.
Callback functions return the scanout position from the CRTC. The
legacy version of the interface receives the device and pipe index,
the modern version receives a pointer to the CRTC. We keep the
legacy version until all drivers have been converted.
v4:
* 80-character line fixes
v3:
* refactor drm_calc_vbltimestamp_from_scanoutpos() to minimize
code duplication
* define types for get_scanout_position() callbacks
v2:
* fix logical op in drm_calc_vbltimestamp_from_scanoutpos()
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Tested-by: Yannick Fertré <yannick.fertre@st.com>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200123135943.24140-3-tzimmermann@suse.de
VBLANK interrupts can be disabled immediately or with a delay, where the
latter is the default. The former option can be selected by setting
get_vblank_timestamp and enabling vblank_disable_immediate in struct
drm_device. Simplify the code in preparation of the removal of struct
drm_device.get_vblank_timestamp.
v3:
* remove internal setup of vblank_disable_immediate
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200123135943.24140-2-tzimmermann@suse.de
The current codebase makes use of the zero-length array language
extension to the C90 standard, but the preferred mechanism to declare
variable-length types such as these ones is a flexible array member[1][2],
introduced in C99:
struct foo {
int stuff;
struct boo array[];
};
By making use of the mechanism above, we will get a compiler warning
in case the flexible array does not occur last in the structure, which
will help us prevent some kind of undefined behavior bugs from being
inadvertenly introduced[3] to the codebase from now on.
Also, notice that, dynamic memory allocations won't be affected by
this change:
"Flexible array members have incomplete type, and so the sizeof operator
may not be applied. As a quirk of the original implementation of
zero-length arrays, sizeof evaluates to zero."[1]
This issue was found with the help of Coccinelle.
[1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html
[2] https://github.com/KSPP/linux/issues/21
[3] commit 7649773293 ("cxgb3/l2t: Fix undefined behaviour")
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20200212193344.GA27929@embeddedor
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
both crtc_state->adjusted_mode.hdisplay and
crtc_state->adjusted_mode.vdisplay are 0 when switch dpms off,
return -EINVAL cause switch dpms off fail.
Signed-off-by: Zhihui Chen <chenzhihui4@huawei.com>
Signed-off-by: Xinliang Liu <xinliang.liu@linaro.org>
Acked-by: Xinliang Liu <xinliang.liu@linaro.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20191220023004.2658-1-chenzhihui4@huawei.com
Based on work by Bjorn Andersson <bjorn.andersson@linaro.org>,
Jeffrey Hugo <jeffrey.l.hugo@gmail.com>, and
Rob Clark <robdclark@chromium.org>.
Let's read the SUPPORTED_LINK_RATES and/or MAX_LINK_RATE (depending on
the eDP version of the sink) to figure out what eDP rates are
supported and pick the ideal one.
NOTE: I have only personally tested this code on eDP panels that are
1.3 or older. Code reading SUPPORTED_LINK_RATES for DP 1.4+ was
tested by hacking the code to pretend that a table was there.
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Reviewed-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191218143416.v3.9.Ib59207b66db377380d13748752d6fce5596462c5@changeid
If we fail training at a lower DP link rate let's now keep trying
until we run out of rates to try. Basically the algorithm here is to
start at the link rate that is the theoretical minimum and then slowly
bump up until we run out of rates or hit the max rate of the sink. We
query the sink using a DPCD read.
This is, in fact, important in practice. Specifically at least one
panel hooked up to the bridge (AUO B116XAK01) had a theoretical min
rate more than 1.62 GHz (if run at 24 bpp) and fails to train at the
next rate (2.16 GHz). It would train at 2.7 GHz, though.
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Tested-by: Rob Clark <robdclark@gmail.com>
Reviewed-by: Rob Clark <robdclark@gmail.com>
Reviewed-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191218143416.v3.8.I251add713bc5c97225200894ab110ea9183434fd@changeid
We'll re-organize the ti_sn_bridge_enable() function a bit to group
together all the parts relating to link training and split them into a
sub-function. This is not intended to have any functional change and
is in preparation for trying link training several times at different
rates. One small side effect here is that if link training fails
we'll now leave the DP PLL disabled, but that seems like a sane thing
to do.
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Tested-by: Rob Clark <robdclark@gmail.com>
Reviewed-by: Rob Clark <robdclark@gmail.com>
Reviewed-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191218143416.v3.7.I1fc75ad11db9048ef08cfe1ab7322753d9a219c7@changeid
The current bridge driver always forced us to use 24 bits per pixel
over the DP link. This is a waste if you are hooked up to a panel
that only supports 6 bits per color or fewer, since in that case you
can run at 18 bits per pixel and thus end up at a lower DP clock rate.
Let's support this.
While at it, let's clean up the math in the function to avoid rounding
errors (and round in the correct direction when we have to round).
Numbers are sufficiently small (because mode->clock is in kHz) that we
don't need to worry about integer overflow.
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Tested-by: Rob Clark <robdclark@gmail.com>
Reviewed-by: Rob Clark <robdclark@gmail.com>
Reviewed-by: Bjorn Andersson <bjorn.andersson@linaro.org>
[narmstrong: s/ran/can/]
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191218143416.v3.6.Iaf8d698f4e5253d658ae283d2fd07268076a7c27@changeid
At least one panel hooked up to the bridge (AUO B116XAK01) only
supports 1 lane of DP. Let's read this information and stop
hardcoding 4 DP lanes.
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Tested-by: Rob Clark <robdclark@gmail.com>
Reviewed-by: Rob Clark <robdclark@gmail.com>
Reviewed-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191218143416.v3.5.Idbd0051d0de53f7e9d18a291ea33011c0854fcc6@changeid
The driver used to say that the value to program into bridge register
0x93 was dp_lanes - 1. Looking at the datasheet for the bridge, this
is wrong. The data sheet says:
* 1 = 1 lane
* 2 = 2 lanes
* 3 = 4 lanes
A more proper way to express this encoding is min(dp_lanes, 3).
At the moment this change has zero effect because we've hardcoded the
number of DP lanes to 4. ...and (4 - 1) == min(4, 3). How fortunate!
...but soon we'll stop hardcoding the number of lanes.
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Tested-by: Rob Clark <robdclark@gmail.com>
Reviewed-by: Rob Clark <robdclark@gmail.com>
Reviewed-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191218143416.v3.4.If3e2d0493e7b6e8b510ea90d8724ff760379b3ba@changeid
