The resume helpers wait for a vblank to occurre hence IRQ need
to be enabled. This avoids a warning as follows during resume:
WARNING: CPU: 0 PID: 314 at drivers/gpu/drm/drm_atomic_helper.c:1249 drm_atomic_helper_wait_for_vblanks.part.1+0x284/0x288
[CRTC:28:crtc-0] vblank wait timed out
Signed-off-by: Stefan Agner <stefan@agner.ch>
With commit 0a70c998d0 ("drm/fsl-dcu: enable pixel clock when
enabling CRTC") the pixel clock is controlled by the CRTC code.
Disabling the pixel clock in suspend leads to a warning due to
the second clk_disable_unprepare call:
WARNING: CPU: 0 PID: 359 at drivers/clk/clk.c:594 clk_core_disable+0x8c/0x90
Remove clk_disable_unprepare call for pixel clock to avoid
unbalanced clock disable on suspend.
Fixes: 0a70c998d0 ("drm/fsl-dcu: enable pixel clock when enabling CRTC")
Signed-off-by: Stefan Agner <stefan@agner.ch>
Commit 18dddadc78 ("drm/atomic: Introduce drm_atomic_helper_shutdown")
introduced a new helper to shutdown all CRTCs to replace the buggy
drm_crtc_force_disable_all() function. Make use of the new atomic
helper drm_atomic_helper_shutdown() to shutdown CRTCs.
Signed-off-by: Stefan Agner <stefan@agner.ch>
Make use of the irq_preinstall/uninstall callback to clear and
mask all interrupts. Use write 1 to clear as documented by the
data sheet (writing a 0 seems to have cleared interrupt status
too). Remove fsl_dcu_drm_irq_init and call drm_irq_install
directly from fsl_dcu_load makes error handling a bit simpler.
Do not set irq_enabled since drm_irq_install is taking care of
it.
Signed-off-by: Stefan Agner <stefan@agner.ch>
Again cleanup before irq disabling doesn't really stop the races,
so just drop it. Proper fix would be to put drm_atomic_helper_shutdown
before everything gets cleaned up.
Cc: Stefan Agner <stefan@agner.ch>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Stefan Agner <stefan@agner.ch>
Less code ftw.
This converts all drivers except the tinydrm helper module. That one
needs more work, since it gets the THIS_MODULE reference from
tinydrm.ko instead of the actual driver module like it should.
Probably needs a similar trick like I used here with generating the
entire struct with a macro.
Cc: Noralf Trønnes <noralf@tronnes.org>
Reviewed-by: Sean Paul <seanpaul@chromium.org>
Reviewed-by: Liviu Dudau <Liviu.Dudau@arm.com>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20170308141257.12119-24-daniel.vetter@ffwll.ch
The vblank hooks in struct drm_driver are deprecated and only meant for
legacy drivers. For modern drivers with DRIVER_MODESET flag, the hooks
in struct drm_crtc_funcs should be used instead.
Signed-off-by: Shawn Guo <shawn.guo@linaro.org>
Cc: Stefan Agner <stefan@agner.ch>
Acked-by: Stefan Agner <stefan@agner.ch>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/1486458995-31018-10-git-send-email-shawnguo@kernel.org
Core code already makes drm_driver.get_vblank_counter hook optional by
letting drm_vblank_no_hw_counter be the default implementation for the
function hook. So the drm_vblank_no_hw_counter assignment in the driver
code becomes redundant and can be removed now.
Signed-off-by: Shawn Guo <shawn.guo@linaro.org>
Cc: Alexey Brodkin <abrodkin@synopsys.com>
Cc: Liviu Dudau <liviu.dudau@arm.com>
Cc: Mali DP Maintainers <malidp@foss.arm.com>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Boris Brezillon <boris.brezillon@free-electrons.com>
Cc: Inki Dae <inki.dae@samsung.com>
Cc: Stefan Agner <stefan@agner.ch>
Cc: Xinliang Liu <z.liuxinliang@hisilicon.com>
Cc: Daniel Vetter <daniel.vetter@intel.com>
Cc: Philipp Zabel <p.zabel@pengutronix.de>
Cc: CK Hu <ck.hu@mediatek.com>
Cc: Neil Armstrong <narmstrong@baylibre.com>
Cc: Rob Clark <robdclark@gmail.com>
Cc: Marek Vasut <marex@denx.de>
Cc: Ben Skeggs <bskeggs@redhat.com>
Cc: Tomi Valkeinen <tomi.valkeinen@ti.com>
Cc: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Cc: Mark Yao <mark.yao@rock-chips.com>
Cc: Benjamin Gaignard <benjamin.gaignard@linaro.org>
Cc: Maxime Ripard <maxime.ripard@free-electrons.com>
Cc: Jyri Sarha <jsarha@ti.com>
Cc: Eric Anholt <eric@anholt.net>
Acked-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Acked-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Acked-by: Neil Armstrong <narmstrong@baylibre.com>
Acked-by: Russell King <rmk+kernel@armlinux.org.uk>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Acked-by: Alexey Brodkin <abrodkin@synopsys.com>
Acked-by: Liviu Dudau <liviu.dudau@arm.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/1486458995-31018-3-git-send-email-shawnguo@kernel.org
Instead of receiving the num_crts as a parameter, we can read it
directly from the mode_config structure. I audited the drivers that
invoke this helper and I believe all of them initialize the mode_config
struct accordingly, prior to calling the fb_helper.
I used the following coccinelle hack to make this transformation, except
for the function headers and comment updates. The first and second
rules are split because I couldn't find a way to remove the unused
temporary variables at the same time I removed the parameter.
// <smpl>
@r@
expression A,B,D,E;
identifier C;
@@
(
- drm_fb_helper_init(A,B,C,D)
+ drm_fb_helper_init(A,B,D)
|
- drm_fbdev_cma_init_with_funcs(A,B,C,D,E)
+ drm_fbdev_cma_init_with_funcs(A,B,D,E)
|
- drm_fbdev_cma_init(A,B,C,D)
+ drm_fbdev_cma_init(A,B,D)
)
@@
expression A,B,C,D,E;
@@
(
- drm_fb_helper_init(A,B,C,D)
+ drm_fb_helper_init(A,B,D)
|
- drm_fbdev_cma_init_with_funcs(A,B,C,D,E)
+ drm_fbdev_cma_init_with_funcs(A,B,D,E)
|
- drm_fbdev_cma_init(A,B,C,D)
+ drm_fbdev_cma_init(A,B,D)
)
@@
identifier r.C;
type T;
expression V;
@@
- T C;
<...
when != C
- C = V;
...>
// </smpl>
Changes since v1:
- Rebased on top of the tip of drm-misc-next.
- Remove mention to sti since a proper fix got merged.
Suggested-by: Daniel Vetter <daniel.vetter@intel.com>
Signed-off-by: Gabriel Krisman Bertazi <krisman@collabora.co.uk>
Reviewed-by: Eric Anholt <eric@anholt.net>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/20170202162640.27261-1-krisman@collabora.co.uk
The integer returned by the unload hook is ignored by the drm core, so
let's make it void.
This patch was created using the following Coccinelle semantic script
(except for the declaration and comment in drm_drv.h):
Compile-tested only.
// <smpl>
@ get_name @
struct drm_driver drv;
identifier fn;
@@
drv.unload = fn;
@ replace_type @
identifier get_name.fn;
@@
- int
+ void
fn (...)
{
...
}
@ remove_return_param @
identifier get_name.fn;
@@
void fn (...)
{
<...
if (...)
return
- ...
;
...>
}
@ drop_final_return @
identifier get_name.fn;
@@
void fn (...)
{
...
- return 0;
}
// </smpl>
Suggested-by: Daniel Vetter <daniel.vetter@intel.com>
Signed-off-by: Gabriel Krisman Bertazi <krisman@collabora.co.uk>
Acked-by: Christian König <christian.koenig@amd.com>.
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/20170106175731.29196-1-krisman@collabora.co.uk
Several DRM drivers print the same initialization message right after
drm_dev_register, so move that to common code. The exception is i915,
which uses its own register handle, so let it keep its own message.
Notice that this was tested only with Exynos, but looks simple enough
for the other drivers.
Signed-off-by: Gabriel Krisman Bertazi <krisman@collabora.co.uk>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/20161228143216.26821-2-krisman@collabora.co.uk
fsl is already fully demidlayered in the probe function, but for
convenience stuck with drm_put_dev. Call the unregister/unref parts
separately, to make sure this driver works correct.
v2: Rebase.
Cc: Lucas Stach <l.stach@pengutronix.de>
Cc: Stefan Agner <stefan@agner.ch>
Reviewed-by: Lucas Stach <l.stach@pengutronix.de>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20161213175449.24525-1-daniel.vetter@ffwll.ch
Some fixes and cleanup, mainly around fbdev emulation. It also adds a
new module parameter which allows to specify the color depth/bpp for
the fbdev emulation (like the IMX DRM driver).
* tag 'drm-fsl-dcu-for-next' of http://git.agner.ch/git/linux-drm-fsl-dcu:
drm/fsl-dcu: introduce kernel parameter to specify fbdev depth
drm/fsl-dcu: remove separate compilation unit for fbdev emulation
drm/fsl-dcu: Propagate the real error code
drm/fsl-dcu: Remove unneeded NULL check
drm/fsl-dcu: disable outputs before unloading driver
drm/fsl-dcu: unload driver before disabling clocks
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Backmerge tag 'v4.9-rc8' into drm-next
Linux 4.9-rc8
Daniel requested this so we could apply some follow on fixes cleanly to -next.
Add a kernel parameter legancyfb_depth (like the i.MX drm driver)
to control the legancy fbdev depth. Default to the so far hard
coded depth of 24-bit. Currently changing the framebuffer depth
is not possible from user space when using the fbdev emulation
layer... This provides a rudimentary mechanism to change depth
without having to change kernel code.
Signed-off-by: Stefan Agner <stefan@agner.ch>
The separate file fsl_dcu_drm_fbdev.c only initialized fbdev
emulation which is a one-line operation. There is not much more
code on sight which justifies a separate file, hence call the
initialization helper directly from the drv file.
Signed-off-by: Stefan Agner <stefan@agner.ch>
In case of platform_get_irq() failure, let's propagate the real
error code, instead of a 'fake' one.
Signed-off-by: Fabio Estevam <fabio.estevam@nxp.com>
Signed-off-by: Stefan Agner <stefan@agner.ch>
devm_ioremap_resource() performs NULL check for the 'res' argument,
so remove the unneeded check.
Signed-off-by: Fabio Estevam <fabio.estevam@nxp.com>
Signed-off-by: Stefan Agner <stefan@agner.ch>
Make sure that all outputs are disabled before unloading the DRM
driver. Otherwise vblank handling is not shut down properly and
warnings such as this appear:
WARNING: CPU: 0 PID: 540 at drivers/gpu/drm/drm_irq.c:339 drm_vblank_cleanup+0x5c/0x94
Signed-off-by: Stefan Agner <stefan@agner.ch>
Use drm_put_dev to unload the driver before disabling clocks.
Otherwise the driver might read a register during unload which
leads to an external abort.
Signed-off-by: Stefan Agner <stefan@agner.ch>
The IRQ status and mask registers are not "double buffered" according
to the reference manual. Hence, there is no extra transfer/update
write needed when modifying these registers.
Signed-off-by: Stefan Agner <stefan@agner.ch>
The pixel clock should not be on if the CRTC is not in use, hence
move clock enable/disable calls into CRTC callbacks.
Signed-off-by: Stefan Agner <stefan@agner.ch>
Tested-By: Meng Yi <meng.yi@nxp.com>
Do not use encoder disable/enable callbacks to control bypass
mode as this seems to mess with the signals not liked by
displays. This also makes more sense since the encoder is
already defined to be parallel RGB/LVDS at creation time.
Signed-off-by: Stefan Agner <stefan@agner.ch>
Tested-By: Meng Yi <meng.yi@nxp.com>
- more core cleanup patches to prep drm_file to be used for
kernel-internal contexts (David Herrmann)
- more split-up+docs for drm_crtc.c
- lots of small fixes and polish all over
* tag 'topic/drm-misc-2016-09-25' of git://anongit.freedesktop.org/drm-intel: (37 commits)
drm: bridge: analogix/dp: mark symbols static where possible
drm/bochs: mark bochs_connector_get_modes() static
drm/bridge: analogix_dp: Improve panel on time
drm/bridge: analogix_dp: Don't read EDID if panel present
drm/bridge: analogix_dp: Remove duplicated code
Revert "drm/i2c: tda998x: don't register the connector"
drm: Fix plane type uabi breakage
dma-buf/sync_file: free fences array in num_fences is 1
drm/i2c: tda998x: don't register the connector
drm: Don't swallow error codes in drm_dev_alloc()
drm: Distinguish no name from ENOMEM in set_unique()
drm: Remove dirty property from docs
drm/doc: Document color space handling
drm: Extract drm_color_mgmt.[hc]
drm/doc: Polish plane composition property docs
drm: Conslidate blending properties in drm_blend.[hc]
drm/doc: Polish for drm_plane.[hc]
drm: Extract drm_plane.[hc]
drm/tilcdc: Add atomic and crtc headers to crtc.c
drm: Fix typo in encoder docs
...
There are many reasons other than ENOMEM that drm_dev_init() can
fail. Return ERR_PTR rather than NULL to be able to distinguish
these in the caller.
Signed-off-by: Tom Gundersen <teg@jklm.no>
Signed-off-by: Sean Paul <seanpaul@chromium.org>
Link: http://patchwork.freedesktop.org/patch/msgid/20160921145919.13754-2-teg@jklm.no
In fsl_dcu_drm_pm_resume() we should disable the previously enabled
clock (fsl_dev->clk) when enabling fsl_dev->pix_clk fails.
Signed-off-by: Fabio Estevam <fabio.estevam@nxp.com>
Signed-off-by: Stefan Agner <stefan@agner.ch>
Since using clk_register_divider to setup the pixel clock, regmap
is no longer used. Regmap did take care of DCU using different
endianness. Check endianness using the device-tree property
"big-endian" to determine the location of DIV_RATIO.
Cc: stable@vger.kernel.org
Fixes: 2d701449bc ("drm/fsl-dcu: use common clock framework for pixel clock divider")
Reported-by: Meng Yi <meng.yi@nxp.com>
Signed-off-by: Stefan Agner <stefan@agner.ch>
Tested-by: Meng Yi <meng.yi@nxp.com>
The patchset contains a new helper in drm_fb_cma_helper.c for suspend/
resume when using cma backed framebuffers.
* 'for-next' of http://git.agner.ch/git/linux-drm-fsl-dcu:
drm/fsl-dcu: disable vblank events on CRTC disable
drm/fsl-dcu: implement suspend/resume using atomic helpers
drm/fsl-dcu: use clk helpers
drm/fsl-dcu: move layer initialization to plane file
drm/fsl-dcu: store layer registers in soc_data
drm/fb_cma_helper: add suspend helper
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Back-merge tag 'v4.7-rc5' into drm-next
Linux 4.7-rc5
The fsl-dcu pull needs -rc3 so go to -rc5 for now.
Use the drm_atomic_helper_suspend() and drm_atomic_helper_resume()
helpers to implement subsystem-level suspend/resume. This replaces
the (non-functional) regmap cache based suspend resume functionality.
Signed-off-by: Stefan Agner <stefan@agner.ch>
Use clk_prepare_enable and clk_disable_unprepare helpers. This also
fixes a sequence issue in the enable path which lead to a warning
on resume.
Signed-off-by: Stefan Agner <stefan@agner.ch>
Store the number of registers per layer in soc_data. This is
more consistent with how the rest of SoC specific data are
handled.
Signed-off-by: Stefan Agner <stefan@agner.ch>
Using flat regmap cache instead of RB-tree to avoid the following
lockdep warning on driver load:
WARNING: CPU: 0 PID: 1 at kernel/locking/lockdep.c:2755 lockdep_trace_alloc+0x15c/0x160()
DEBUG_LOCKS_WARN_ON(irqs_disabled_flags(flags))
The RB-tree regmap cache needs to allocate new space on first
writes. However, allocations in an atomic context (e.g. when a
spinlock is held) are not allowed. The function regmap_write
calls map->lock, which acquires a spinlock in the fast_io case.
Since the FSL DCU driver uses MMIO, the regmap bus of type
regmap_mmio is being used which has fast_io set to true.
Use flat regmap cache and specify max register to be large
enouth to cover all registers available in LS1021a and Vybrids
register space.
Signed-off-by: Stefan Agner <stefan@agner.ch>
Cc: Mark Brown <broonie@kernel.org>
Cc: stable@vger.kernel.org
This was added in
commit 0a3e67a4ca
Author: Jesse Barnes <jbarnes@virtuousgeek.org>
Date: Tue Sep 30 12:14:26 2008 -0700
drm: Rework vblank-wait handling to allow interrupt reduction.
to stay backwards-compatible with old UMS code that didn't even tell
the kernel when it did a modeset, so that the kernel could
save/restore vblank counters. At worst this means vblanks will be
somewhat funky on a setup that very likely no one still runs.
So let's just nuke it.
Plan B would be to set it unconditionally in drm_vblank_init for kms
drivers, instead of in each driver separately. So if this patch breaks
anything please only restore the hunks in drmP.h and drm_irq.c, plus
add a check for DRIVER_MODESET in drm_vblank_init.
Stumbled over this in a discussion on irc with Chris.
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Alex Deucher <alexander.deucher@amd.com>
Cc: Liviu Dudau <liviu.dudau@arm.com>
Cc: Russell King <rmk+kernel@arm.linux.org.uk>
Cc: Thierry Reding <thierry.reding@gmail.com>
Cc: Eric Anholt <eric@anholt.net>
Cc: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Cc: Inki Dae <inki.dae@samsung.com>
Cc: Tomi Valkeinen <tomi.valkeinen@ti.com>
Cc: Mark Yao <mark.yao@rock-chips.com>
Cc: Sascha Hauer <s.hauer@pengutronix.de>
Cc: Philipp Zabel <p.zabel@pengutronix.de>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Acked-by: Liviu Dudau <Liviu.Dudau@arm.com>
Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Tested-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
The driver supports now a second platform and received several
fixes, hence a version increment is justified.
Signed-off-by: Stefan Agner <stefan@agner.ch>
Free fbdev CMA using drm_fbdev_cma_fini on unload. This fixes
a warning when unloading the driver:
WARNING: CPU: 0 PID: 164 at drivers/gpu/drm/drm_crtc.c:5930 drm_mode_config_cleanup+0x204/0x208
Signed-off-by: Stefan Agner <stefan@agner.ch>
The driver uses different variable names for struct drm_device
across functions which is confusing. Stick to the more common
variable name dev. While at it, remove unnecessary if statement
in error handling.
Signed-off-by: Stefan Agner <stefan@agner.ch>
Add driver for the TCON (timing controller) module. The TCON module
is a separate module attached after the DCU (display controller
unit). Each DCU instance has its own, directly connected TCON
instance. The DCU's RGB and timing signals are passing through
the TCON module. TCON can provide timing signals for raw TFT panels
or operate in a bypass mode which leaves all signals unaltered.
The driver currently only supports the bypass mode.
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Stefan Agner <stefan@agner.ch>
Use the common clock framework to calculate the pixel clock
dividier. The previous implementation rounded down the calculated
factor. Thanks to the CLK_DIVIDER_ROUND_CLOSEST flag using the
common clock framework divider implementation improves the pixel
clock accuracy in some cases. Ontop of that it also allows to see
the actual pixel clock in the sysfs clock summary.
Signed-off-by: Stefan Agner <stefan@agner.ch>
The Vybrid DCU variant has two independent clock inputs, one
for the registers (IPG bus clock) and one for the pixel clock.
Support this distinction in the DCU DRM driver while staying
backward compatible for old device trees.
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Stefan Agner <stefan@agner.ch>
Fix error handling during probe by reordering initialization and
adding a error path which disables clock again. Also disable the
clock on remove.
Signed-off-by: Stefan Agner <stefan@agner.ch>
The state of the interrupt mask register on initialization is
unknown, e.g. U-Boot could already used the DCU. So depending on
the boot loader, the outcome of the interrupt mask register could
be different. A defined state is much more preferable. Also, there
is no value in keeping interrupts enabled which we don't need.
Therefor, mask all interrupts on initialization.
Signed-off-by: Stefan Agner <stefan@agner.ch>
It is not common to do regmap return value checks, especially not
for memory mapped device. We can rule out most error returns since
the conditions are static and we know they are ok (e.g. offset
aligned to register stride). Also without proper error handling
they are not really valuable for the user. Hence remove most of
them.
The check in the interrupt handler is worth keeping since a
volatile register won't be readable in case register caching is
still enabled.
Signed-off-by: Stefan Agner <stefan@agner.ch>
Since we are using cached registers, we need to specify volatile
registers explicitly to avoid reading their value from the cache.
This allows to read the correct interrupt status in fsl_dcu_drm_irq
and clear the asserted bits only.
Signed-off-by: Stefan Agner <stefan@agner.ch>
