Linux 6.1-rc6

This is needed for drm-misc-next and tegra.

Signed-off-by: Dave Airlie <airlied@redhat.com>

Commit 6bed2ea3cb38 ("drm/vc4: hdmi: Reset link on hotplug") introduced
the vc4_hdmi_reset_link() function. This function dereferences the
"connector" pointer before checking whether it is NULL or not.

Rework variable assignment to avoid this issue.

Fixes: 6bed2ea3cb38 ("drm/vc4: hdmi: Reset link on hotplug")
Signed-off-by: José Expósito <jose.exposito89@gmail.com>
Link: https://lore.kernel.org/r/20221110134752.238820-3-jose.exposito89@gmail.com
Signed-off-by: Maxime Ripard <maxime@cerno.tech>

Simplify vc4_hdmi_supports_scrambling() by changing its first parameter
from struct drm_encoder to struct vc4_hdmi.

Signed-off-by: José Expósito <jose.exposito89@gmail.com>
Link: https://lore.kernel.org/r/20221110134752.238820-2-jose.exposito89@gmail.com
Signed-off-by: Maxime Ripard <maxime@cerno.tech>

The drm_atomic_get_new_private_obj_state() function returns NULL
on error path, drm_atomic_get_old_private_obj_state() function
returns NULL on error path, too, they does not return error pointers.

By the way, vc4_hvs_get_new/old_global_state() should return
ERR_PTR(-EINVAL), otherwise there will be null-ptr-defer issue,
such as follows:

In function vc4_atomic_commit_tail():
  |-- old_hvs_state = vc4_hvs_get_old_global_state(state); <-- return NULL
  |-- if (WARN_ON(IS_ERR(old_hvs_state))) <-- no return
  |-- unsigned long state_rate = max(old_hvs_state->core_clock_rate,
	new_hvs_state->core_clock_rate); <-- null-ptr-defer

Fixes: 9ec03d7f1ed3 ("drm/vc4: kms: Wait on previous FIFO users before a commit")
Signed-off-by: Gaosheng Cui <cuigaosheng1@huawei.com>
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Link: https://patchwork.freedesktop.org/patch/msgid/20221110094445.2930509-6-cuigaosheng1@huawei.com

A problem about modprobe vc4 failed is triggered with the following log
given:

 [  420.327987] Error: Driver 'vc4_hvs' is already registered, aborting...
 [  420.333904] failed to register platform driver vc4_hvs_driver [vc4]: -16
 modprobe: ERROR: could not insert 'vc4': Device or resource busy

The reason is that vc4_drm_register() returns platform_driver_register()
directly without checking its return value, if platform_driver_register()
fails, it returns without unregistering all the vc4 drivers, resulting the
vc4 can never be installed later.
A simple call graph is shown as below:

 vc4_drm_register()
   platform_register_drivers() # all vc4 drivers are registered
   platform_driver_register()
     driver_register()
       bus_add_driver()
         priv = kzalloc(...) # OOM happened
   # return without unregister drivers

Fixing this problem by checking the return value of
platform_driver_register() and do platform_unregister_drivers() if
error happened.

Fixes: c8b75bca92cb ("drm/vc4: Add KMS support for Raspberry Pi.")
Signed-off-by: Yuan Can <yuancan@huawei.com>
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Link: https://patchwork.freedesktop.org/patch/msgid/20221103014705.109322-1-yuancan@huawei.com

Move the generic fbdev implementation into its own source and header
file. Adapt drivers. No functional changes, but some of the internal
helpers have been renamed to fit into the drm_fbdev_ naming scheme.

v3:
	* rename drm_fbdev.{c,h} to drm_fbdev_generic.{c,h}
	* rebase onto vmwgfx changes
	* rebase onto xlnx changes
	* fix include statements in amdgpu

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20221103151446.2638-22-tzimmermann@suse.de

drm-misc-next for 6.2:

UAPI Changes:

Cross-subsystem Changes:
- dma-buf: locking improvements
- firmware: New API in the RaspberryPi firmware driver used by vc4

Core Changes:
- client: Null pointer dereference fix in drm_client_buffer_delete()
- mm/buddy: Add back random seed log
- ttm: Convert ttm_resource to use size_t for its size, fix for an
  undefined behaviour

Driver Changes:
- bridge:
  - adv7511: use dev_err_probe
  - it6505: Fix return value check of pm_runtime_get_sync
- panel:
  - sitronix: Fixes and clean-ups
- lcdif: Increase DMA burst size
- rockchip: runtime_pm improvements
- vc4: Fix for a regression preventing the use of 4k @ 60Hz, and
  further HDMI rate constraints check.
- vmwgfx: Cursor improvements

Signed-off-by: Dave Airlie <airlied@redhat.com>

From: Maxime Ripard <maxime@cerno.tech>
Link: https://patchwork.freedesktop.org/patch/msgid/20221103083437.ksrh3hcdvxaof62l@houat

Commit ae71ab585c81 ("drm/vc4: hdmi: Enforce the minimum rate at
runtime_resume") reintroduced the call to clk_set_min_rate in an attempt
to fix the boot without a monitor connected on the RaspberryPi3.

However, that introduced a regression breaking the display output
entirely (black screen but no vblank timeout) on the Pi4.

This is due to the fact that we now have in a typical modeset at boot,
in vc4_hdmi_encoder_pre_crtc_configure(), we have a first call to
clk_set_min_rate() asking for the minimum rate of the HSM clock for our
given resolution, and then a call to pm_runtime_resume_and_get(). We
will thus execute vc4_hdmi_runtime_resume() which, since the commit
mentioned above, will call clk_set_min_rate() a second time with the
absolute minimum rate we want to enforce on the HSM clock.

We're thus effectively erasing the minimum mandated by the mode we're
trying to set. The fact that only the Pi4 is affected is due to the fact
that it uses a different clock driver that tries to minimize the HSM
clock at all time. It will thus lower the HSM clock rate to 120MHz on
the second clk_set_min_rate() call.

The Pi3 doesn't use the same driver and will not change the frequency on
the second clk_set_min_rate() call since it's still within the new
boundaries and it doesn't have the code to minimize the clock rate as
needed. So even though the boundaries are still off, the clock rate is
still the right one for our given mode, so everything works.

There is a lot of moving parts, so I couldn't find any obvious
solution:

  - Reverting the original is not an option, as that would break the Pi3
    again.

  - We can't move the clk_set_min_rate() call in _pre_crtc_configure()
    since because, on the Pi3, the HSM clock has the CLK_SET_RATE_GATE
    flag which prevents the clock rate from being changed after it's
    been enabled. Our calls to clk_set_min_rate() can change it, so they
    need to be done before clk_prepare_enable().

  - We can't remove the call to clk_prepare_enable() from the
    runtime_resume hook to put it into _pre_crtc_configure() either,
    since we need that clock to be enabled to access the registers, and
    we can't count on the fact that the display will be active in all
    situations (doing any CEC operation, or listing the modes while
    inactive are valid for example()).

  - We can't drop the call to clk_set_min_rate() in
    _pre_crtc_configure() since we would need to still enforce the
    minimum rate for a given resolution, and runtime_resume doesn't have
    access to the current mode, if there's any.

  - We can't copy the TMDS character rate into vc4_hdmi and reuse it
    since, because it's part of the KMS atomic state, it needs to be
    protected by a mutex. Unfortunately, some functions (CEC operations,
    mostly) can be reentrant (through the CEC framework) and still need
    a pm_runtime_get.

However, we can work around this issue by leveraging the fact that the
clk_set_min_rate() calls set boundaries for its given struct clk, and
that each different clk_get() call will return a different instance of
struct clk. The clock framework will then aggregate the boundaries for
each struct clk instances linked to a given clock, plus its hardware
boundaries, and will use that.

We can thus get an extra HSM clock user for runtime_pm use only, and use
our different clock instances depending on the context: runtime_pm will
use its own to set the absolute minimum clock setup so that we never
lock the CPU waiting for a register access, and the modeset part will
set its requirement for the current resolution. And we let the CCF do
the coordination.

It's not an ideal solution, but it's fairly unintrusive and doesn't
really change any part of the logic so it looks like a rather safe fix.

Link: https://bugzilla.redhat.com/show_bug.cgi?id=2136234
Fixes: ae71ab585c81 ("drm/vc4: hdmi: Enforce the minimum rate at runtime_resume")
Reported-by: Peter Robinson <pbrobinson@gmail.com>
Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
Tested-by: Peter Robinson <pbrobinson@gmail.com>
Link: https://lore.kernel.org/r/20221021131339.2203291-1-maxime@cerno.tech
Signed-off-by: Maxime Ripard <maxime@cerno.tech>

A comment introduced by commit 6bed2ea3cb38 ("drm/vc4: hdmi: Reset link
on hotplug") mentions a drm_atomic_helper_connector_hdmi_reset_link()
function that was part of the earlier versions but got moved internally
and is now named vc4_hdmi_reset_link(). Let's fix the function name.

Fixes: 6bed2ea3cb38 ("drm/vc4: hdmi: Reset link on hotplug")
Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
Link: https://lore.kernel.org/r/20221024093634.118190-2-maxime@cerno.tech
Signed-off-by: Maxime Ripard <maxime@cerno.tech>

We access some fields protected by our internal mutex in
vc4_hdmi_reset_link() (saved_adjusted_mode, output_bpc, output_format)
and are calling functions that need to have that lock taken
(vc4_hdmi_supports_scrambling()).

However, the current code doesn't lock that mutex. Let's make sure it
does.

Fixes: 6bed2ea3cb38 ("drm/vc4: hdmi: Reset link on hotplug")
Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
Link: https://lore.kernel.org/r/20221024093634.118190-1-maxime@cerno.tech
Signed-off-by: Maxime Ripard <maxime@cerno.tech>