Allocating a shadow buffer of the height of the buffer object does
not support fbdev overallocation. Use surface height instead.
Signed-off-by: NThomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: NNoralf Trønnes <noralf@tronnes.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20211110103702.374-7-tzimmermann@suse.de

Clamp the fbdev surface size of the available maximumi height to avoid
failing to init console emulation. An example error is shown below.

  bad framebuffer height 2304, should be >= 768 && <= 768
  [drm] Initialized simpledrm 1.0.0 20200625 for simple-framebuffer.0 on minor 0
  simple-framebuffer simple-framebuffer.0: [drm] *ERROR* fbdev: Failed to setup generic emulation (ret=-22)

This is especially a problem with drivers that have very small screen
sizes and cannot over-allocate at all.

v2:
	* reduce warning level (Ville)
Signed-off-by: NThomas Zimmermann <tzimmermann@suse.de>
Fixes: 11e8f5fd ("drm: Add simpledrm driver")
Reviewed-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: NAlex Deucher <alexander.deucher@amd.com>
Reported-by: NAmanoel Dawod <kernel@amanoeldawod.com>
Reported-by: NZoltán Kővágó <dirty.ice.hu@gmail.com>
Reported-by: NMichael Stapelberg <michael+lkml@stapelberg.ch>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Maxime Ripard <maxime@cerno.tech>
Cc: dri-devel@lists.freedesktop.org
Cc: <stable@vger.kernel.org> # v5.14+
Link: https://patchwork.freedesktop.org/patch/msgid/20211005070355.7680-1-tzimmermann@suse.deSigned-off-by: NDave Airlie <airlied@redhat.com>

This reverts commit 7c5f2eec.

This patchset breaks on intel platforms and was previously NACK'd by
Ville.

Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: Fernando Ramos <greenfoo@u92.eu>
Acked-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: NSean Paul <seanpaul@chromium.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20211002154542.15800-13-sean@poorly.run

As requested in Documentation/gpu/todo.rst, replace driver calls to
drm_modeset_lock_all() with DRM_MODESET_LOCK_ALL_BEGIN() and
DRM_MODESET_LOCK_ALL_END()
Signed-off-by: NFernando Ramos <greenfoo@u92.eu>
Reviewed-by: NSean Paul <sean@poorly.run>
Signed-off-by: NSean Paul <seanpaul@chromium.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20210924064324.229457-5-greenfoo@u92.eu

fix typo for drm

v1->v2:
respin with the change "iff ==> implies that"
Signed-off-by: NCai Huoqing <caihuoqing@baidu.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20210730132729.376-1-caihuoqing@baidu.com

Framebuffer devices that are registered by DRM drivers for fbdev emulation
have a "drmfb" suffix in their name. But makes them to be quite confusing
for drivers that already have "drm" in their name:

$ cat /proc/fb
0 rockchipdrmdrmfb

$ cat /proc/fb
0 simpledrmdrmfb

Also, there isn't a lot of value in adding these "drmfb" suffices to their
names, since users shouldn't really care if the FB devices were registered
by a real fbdev driver or a DRM driver using the fbdev emulation.

What programs should be interested about is if there's a DRM device, and
there are better ways to query that info than reading this procfs entry.

So let's just remove the suffix, which leads to much better device names:

$ cat /proc/fb
0 rockchipdrm

$ cat /proc/fb
0 simpledrm
Suggested-by: NThomas Zimmermann <tzimmermann@suse.de>
Signed-off-by: NJavier Martinez Canillas <javierm@redhat.com>
Signed-off-by: NThomas Zimmermann <tzimmermann@suse.de>
Link: https://patchwork.freedesktop.org/patch/msgid/20210525151313.3379622-1-javierm@redhat.com

drm_fbdev_cleanup() can be called when fb_helper->buffer is null, hence
fb_helper->buffer should be checked before calling
drm_client_buffer_vunmap(). This buffer is also checked in
drm_client_framebuffer_delete(), so we should also do the same thing for
drm_client_buffer_vunmap().

[  199.128742] RIP: 0010:drm_client_buffer_vunmap+0xd/0x20
[  199.129031] Code: 43 18 48 8b 53 20 49 89 45 00 49 89 55 08 5b 44 89 e0 41 5c 41 5d 41 5e 5d
c3 0f 1f 00 53 48 89 fb 48 8d 7f 10 e8 73 7d a1 ff <48> 8b 7b 10 48 8d 73 18 5b e9 75 53 fc ff 0
f 1f 44 00 00 48 b8 00
[  199.130041] RSP: 0018:ffff888103f3fc88 EFLAGS: 00010282
[  199.130329] RAX: 0000000000000001 RBX: 0000000000000000 RCX: ffffffff8214d46d
[  199.130733] RDX: 1ffffffff079c6b9 RSI: 0000000000000246 RDI: ffffffff83ce35c8
[  199.131119] RBP: ffff888103d25458 R08: 0000000000000001 R09: fffffbfff0791761
[  199.131505] R10: ffffffff83c8bb07 R11: fffffbfff0791760 R12: 0000000000000000
[  199.131891] R13: ffff888103d25468 R14: ffff888103d25418 R15: ffff888103f18120
[  199.132277] FS:  00007f36fdcbb6a0(0000) GS:ffff88815b400000(0000) knlGS:0000000000000000
[  199.132721] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[  199.133033] CR2: 0000000000000010 CR3: 0000000103d26000 CR4: 00000000000006f0
[  199.133420] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[  199.133807] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[  199.134195] Call Trace:
[  199.134333]  drm_fbdev_cleanup+0x179/0x1a0
[  199.134562]  drm_fbdev_client_unregister+0x2b/0x40
[  199.134828]  drm_client_dev_unregister+0xa8/0x180
[  199.135088]  drm_dev_unregister+0x61/0x110
[  199.135315]  mgag200_pci_remove+0x38/0x52 [mgag200]
[  199.135586]  pci_device_remove+0x62/0xe0
[  199.135806]  device_release_driver_internal+0x148/0x270
[  199.136094]  driver_detach+0x76/0xe0
[  199.136294]  bus_remove_driver+0x7e/0x100
[  199.136521]  pci_unregister_driver+0x28/0xf0
[  199.136759]  __x64_sys_delete_module+0x268/0x300
[  199.137016]  ? __ia32_sys_delete_module+0x300/0x300
[  199.137285]  ? call_rcu+0x3e4/0x580
[  199.137481]  ? fpregs_assert_state_consistent+0x4d/0x60
[  199.137767]  ? exit_to_user_mode_prepare+0x2f/0x130
[  199.138037]  do_syscall_64+0x33/0x40
[  199.138237]  entry_SYSCALL_64_after_hwframe+0x44/0xae
[  199.138517] RIP: 0033:0x7f36fdc3dcf7
Signed-off-by: NTong Zhang <ztong0001@gmail.com>
Fixes: 763aea17 ("drm/fb-helper: Unmap client buffer during shutdown")
Cc: Thomas Zimmermann <tzimmermann@suse.de>
Cc: Sam Ravnborg <sam@ravnborg.org>
Cc: Maxime Ripard <mripard@kernel.org>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: David Airlie <airlied@linux.ie>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: dri-devel@lists.freedesktop.org
Cc: <stable@vger.kernel.org> # v5.11+
Signed-off-by: NThomas Zimmermann <tzimmermann@suse.de>
Link: https://patchwork.freedesktop.org/patch/msgid/20210228044625.171151-1-ztong0001@gmail.comSigned-off-by: NMaarten Lankhorst <maarten.lankhorst@linux.intel.com>

drm_fb_helper_modinit has a lot of boilerplate for what is not very
simple functionality.  Just open code it in the only caller using
IS_ENABLED and IS_MODULE, and skip the find_module check as a
request_module is harmless if the module is already loaded (and not
other caller has this find_module check either).
Acked-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NJessica Yu <jeyu@kernel.org>

I tried to fix this for real, but it's very sprawling and lots of
drivers get this mildly wrong one way or the other.
Signed-off-by: NDaniel Vetter <daniel.vetter@intel.com>
Acked-by: NSimon Ser <contact@emersion.fr>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Maxime Ripard <mripard@kernel.org>
Cc: Thomas Zimmermann <tzimmermann@suse.de>
Cc: David Airlie <airlied@linux.ie>
Cc: Daniel Vetter <daniel@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20201211161113.3350061-2-daniel.vetter@ffwll.ch

The DRM core handles legacy gamma-set ioctl by setting GAMMA_LUT and
clearing CTM and DEGAMMA_LUT.

This works fine on HW where we have either:

degamma -> ctm -> gamma -> out

or

ctm -> gamma -> out

However, if the HW has gamma table before ctm, the atomic property
should be DEGAMMA_LUT, and thus we have:

degamma -> ctm -> out

This is fine for userspace which sets gamma table using the properties,
as the userspace can check for the existence of gamma & degamma, but the
legacy gamma-set ioctl does not work.

Change the DRM core to use DEGAMMA_LUT instead of GAMMA_LUT when the
latter is unavailable.
Signed-off-by: NTomi Valkeinen <tomi.valkeinen@ti.com>
Reviewed-by: NLaurent Pinchart <laurent.pinchart@ideasonboard.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20201211114237.213288-3-tomi.valkeinen@ti.com

setcmap_legacy() does not call drm_modeset_unlock_all() in some exits,
add the missed unlocks with goto to fix it.

Fixes: 964c6006 ("drm/fb-helper: separate the fb_setcmap helper into atomic and legacy paths")
Signed-off-by: NChuhong Yuan <hslester96@gmail.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20201203144248.418281-1-hslester96@gmail.com

Flushing the fbdev's shadow buffer requires vmap'ing the BO memory, which
in turn requires pinning the BO. While being pinned, the BO cannot be moved
into VRAM for scanout. Consequently, a concurrent modeset operation that
involves the fbdev framebuffer would likely fail.

Resolve this problem be acquiring the modeset lock of the planes that use
the fbdev framebuffer. On non-atomic drivers, also acquire the mode-config
lock. This serializes the flushing of the framebuffer with concurrent
modeset operations.

v2:
	* only acquire struct drm_fb_helper.lock in damage blitter (Daniel,
	  Christian)
Signed-off-by: NThomas Zimmermann <tzimmermann@suse.de>
Acked-by: NMaxime Ripard <mripard@kernel.org>
Acked-by: NSam Ravnborg <sam@ravnborg.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20201120102545.4047-11-tzimmermann@suse.de

Copy the vmap()'ed instance of struct dma_buf_map before modifying it,
in case the implementation of vunmap() depends on the exact address.
Signed-off-by: NThomas Zimmermann <tzimmermann@suse.de>
Acked-by: NMaxime Ripard <mripard@kernel.org>
Acked-by: NSam Ravnborg <sam@ravnborg.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20201120102545.4047-10-tzimmermann@suse.de

If the damage handling fails, restore the damage area. The next invocation
of the damage worker will then perform the update.

v3:
	* Use drm_WARN_ONCE() with an error message to print warning
v2:
	* print a single warning if dirty callback fails (Daniel, Sebastian)
	* update comment
Signed-off-by: NThomas Zimmermann <tzimmermann@suse.de>
Acked-by: NMaxime Ripard <mripard@kernel.org>
Acked-by: NSam Ravnborg <sam@ravnborg.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20201120102545.4047-9-tzimmermann@suse.de

Introduce a separate function for the blit code and its vmap setup. Done
in preparation of additional changes. No functional changes are made.

v3:
	* Use drm_WARN_ONCE() with an error message to print warning
v2:
	* print a single warning if damage blitter fails
Signed-off-by: NThomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: NSam Ravnborg <sam@ravnborg.org>
Acked-by: NMaxime Ripard <mripard@kernel.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20201120102545.4047-8-tzimmermann@suse.de

Flushing the shadow framebuffer and invoking the dirty callback are two
separate operations, so do them separately. The flush operation is paired
with calls to vmap and vunmap. They are not needed for the dirty callback,
which performs its own invocations if necessary.
Signed-off-by: NThomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: NSam Ravnborg <sam@ravnborg.org>
Acked-by: NMaxime Ripard <mripard@kernel.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20201120102545.4047-7-tzimmermann@suse.de

Returning early in the damage worker if no update is required. Makes the
code more readable. No functional changes are being made.

v3:
	* s/dirty/damage in commit message (Sam)
Signed-off-by: NThomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: NSam Ravnborg <sam@ravnborg.org>
Acked-by: NMaxime Ripard <mripard@kernel.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20201120102545.4047-6-tzimmermann@suse.de

The dirty worker handles all damage updates, instead of just calling
the framebuffer's dirty callback. Rename it to damage worker. Also
rename related variables accordingly. No functional changes are made.
Signed-off-by: NThomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: NSam Ravnborg <sam@ravnborg.org>
Acked-by: NMaxime Ripard <mripard@kernel.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20201120102545.4047-5-tzimmermann@suse.de

The fbdev helper's generic probe function establishes a mapping for
framebuffers without shadow buffer. The clean-up function did not unmap
the buffer object. Add the unmap operation.

As fbdev devices are usally released during system shutdown, this has
not been a problem in practice.
Signed-off-by: NThomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: NSam Ravnborg <sam@ravnborg.org>
Acked-by: NMaxime Ripard <mripard@kernel.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20201120102545.4047-3-tzimmermann@suse.de

If fbdev uses a shadow framebuffer, call the damage handler. Otherwise
the update might not make it to the screen.

v2:
	* mark virtual screen as dirty (Ville)
Signed-off-by: NThomas Zimmermann <tzimmermann@suse.de>
Fixes: 222ec45f ("drm/fb_helper: Support framebuffers in I/O memory")
Acked-by: NMaxime Ripard <mripard@kernel.org>
Acked-by: NSam Ravnborg <sam@ravnborg.org>
Cc: Thomas Zimmermann <tzimmermann@suse.de>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Sam Ravnborg <sam@ravnborg.org>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Maxime Ripard <mripard@kernel.org>
Cc: David Airlie <airlied@linux.ie>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: Gerd Hoffmann <kraxel@redhat.com>
Cc: dri-devel@lists.freedesktop.org
Cc: virtualization@lists.linux-foundation.org
Link: https://patchwork.freedesktop.org/patch/msgid/20201120102545.4047-2-tzimmermann@suse.de

On arm32:

    drivers/gpu/drm/drm_fb_helper.c: In function ‘fb_read_screen_base’:
    include/linux/minmax.h:18:28: warning: comparison of distinct pointer types lacks a cast
    ...
    drivers/gpu/drm/drm_fb_helper.c:2041:22: note: in expansion of macro ‘min’
     2041 |  size_t alloc_size = min(count, PAGE_SIZE);
	  |                      ^~~
    drivers/gpu/drm/drm_fb_helper.c: In function ‘fb_write_screen_base’:
    include/linux/minmax.h:18:28: warning: comparison of distinct pointer types lacks a cast
    ...
    drivers/gpu/drm/drm_fb_helper.c:2115:22: note: in expansion of macro ‘min’
     2115 |  size_t alloc_size = min(count, PAGE_SIZE);
	  |                      ^~~

Indeed, on 32-bit size_t is "unsigned int", not "unsigned long".

Fixes: 222ec45f ("drm/fb_helper: Support framebuffers in I/O memory")
Signed-off-by: NGeert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: NThomas Zimmermann <tzimmermann@suse.de>
Link: https://patchwork.freedesktop.org/patch/msgid/20201110090119.2667326-1-geert+renesas@glider.be

At least sparc64 requires I/O-specific access to framebuffers. This
patch updates the fbdev console accordingly.

For drivers with direct access to the framebuffer memory, the callback
functions in struct fb_ops test for the type of memory and call the rsp
fb_sys_ of fb_cfb_ functions. Read and write operations are implemented
internally by DRM's fbdev helper.

For drivers that employ a shadow buffer, fbdev's blit function retrieves
the framebuffer address as struct dma_buf_map, and uses dma_buf_map
interfaces to access the buffer.

The bochs driver on sparc64 uses a workaround to flag the framebuffer as
I/O memory and avoid a HW exception. With the introduction of struct
dma_buf_map, this is not required any longer. The patch removes the rsp
code from both, bochs and fbdev.

v7:
	* use min_t(size_t,) (kernel test robot)
	* return the number of bytes read/written, if any (fbdev testcase)
v5:
	* implement fb_read/fb_write internally (Daniel, Sam)
v4:
	* move dma_buf_map changes into separate patch (Daniel)
	* TODO list: comment on fbdev updates (Daniel)
Signed-off-by: NThomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Reviewed-by: NSam Ravnborg <sam@ravnborg.org>
Tested-by: NSam Ravnborg <sam@ravnborg.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20201103093015.1063-11-tzimmermann@suse.de

Kernel DRM clients now store their framebuffer address in an instance
of struct dma_buf_map. Depending on the buffer's location, the address
refers to system or I/O memory.

Callers of drm_client_buffer_vmap() receive a copy of the value in
the call's supplied arguments. It can be accessed and modified with
dma_buf_map interfaces.

v6:
	* don't call page_to_phys() on framebuffers in I/O memory;
	  warn instead (Daniel)
Signed-off-by: NThomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Tested-by: NSam Ravnborg <sam@ravnborg.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20201103093015.1063-9-tzimmermann@suse.de

We didn't take the kernel_fb_helper_lock mutex, which protects that
code. While at it, simplify the code
- inline the function (originally shared with kgdb I think)
- drop the error tracking and all the complications
- drop the pointless early out, it served nothing
Acked-by: NThomas Zimmermann <tzimmermann@suse.de>
Signed-off-by: NDaniel Vetter <daniel.vetter@intel.com>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Maxime Ripard <mripard@kernel.org>
Cc: Thomas Zimmermann <tzimmermann@suse.de>
Cc: David Airlie <airlied@linux.ie>
Cc: Daniel Vetter <daniel@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20201007133036.1541639-1-daniel.vetter@ffwll.ch

All slots in sysrq_key_table[] are either used, reserved or at least
commented with their intended use. This patch adds capital letter versions
available, which means adding 26 more entries.

For already existing SysRq operations the user presses Alt-SysRq-<key>, and
for the newly added ones Alt-Shift-SysRq-<key>.
Signed-off-by: NAndrzej Pietrasiewicz <andrzej.p@collabora.com>
Acked-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Link: https://lore.kernel.org/r/20200818112825.6445-2-andrzej.p@collabora.comSigned-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Recent kernels have been reported to panic using the bochs_drm
framebuffer under qemu-system-sparc64 which was bisected to
commit 7a0483ac ("drm/bochs: switch to generic drm fbdev emulation").

The backtrace indicates that the shadow framebuffer copy in
drm_fb_helper_dirty_blit_real() is trying to access the real
framebuffer using a virtual address rather than use an IO access
typically implemented using a physical (ASI_PHYS) access on SPARC.

The fix is to replace the memcpy with memcpy_toio() from io.h.

memcpy_toio() uses writeb() where the original fbdev code
used sbus_memcpy_toio(). The latter uses sbus_writeb().

The difference between writeb() and sbus_memcpy_toio() is
that writeb() writes bytes in little-endian, where sbus_writeb() writes
bytes in big-endian. As endian does not matter for byte writes they are
the same. So we can safely use memcpy_toio() here.

Note that this only fixes bochs, in general fbdev helpers still have
issues with mixing up system memory and __iomem space. Fixing that will
require a lot more work.

v3:
  - Improved changelog (Daniel)
  - Added FIXME to fbdev_use_iomem (Daniel)

v2:
  - Added missing __iomem cast (kernel test robot)
  - Made changelog readable and fix typos (Mark)
  - Add flag to select iomem - and set it in the bochs driver
Signed-off-by: NSam Ravnborg <sam@ravnborg.org>
Reported-by: NMark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
Reported-by: Nkernel test robot <lkp@intel.com>
Tested-by: NMark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
Reviewed-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Cc: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
Cc: Thomas Zimmermann <tzimmermann@suse.de>
Cc: Gerd Hoffmann <kraxel@redhat.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: sparclinux@vger.kernel.org
Link: https://patchwork.freedesktop.org/patch/msgid/20200709193016.291267-1-sam@ravnborg.org
Link: https://patchwork.freedesktop.org/patch/msgid/20200725191012.GA434957@ravnborg.org

Change logging information from dev_info() to drm_info().
Signed-off-by: NSuraj Upadhyay <usuraj35@gmail.com>
Signed-off-by: NSam Ravnborg <sam@ravnborg.org>
Link: https://patchwork.freedesktop.org/patch/msgid/0d37c7a614eb0885f0f0bed18e48a4d26b345a8e.1594136880.git.usuraj35@gmail.com

In the past we had a pile of hacks to orchestrate access between fbdev
emulation and native kms clients. We've tried to streamline this, by
always preferring the kms side above fbdev calls when a drm master
exists, because drm master controls access to the display resources.

Unfortunately this breaks existing userspace, specifically Xorg. When
exiting Xorg first restores the console to text mode using the KDSET
ioctl on the vt. This does nothing, because a drm master is still
around. Then it drops the drm master status, which again does nothing,
because logind is keeping additional drm fd open to be able to
orchestrate vt switches. In the past this is the point where fbdev was
restored, as part of the ->lastclose hook on the drm side.

Now to fix this regression we don't want to go back to letting fbdev
restore things whenever it feels like, or to the pile of hacks we've
had before. Instead try and go with a minimal exception to make the
KDSET case work again, and nothing else.

This means that if userspace does a KDSET call when switching between
graphical compositors, there will be some flickering with fbcon
showing up for a bit. But a) that's not a regression and b) userspace
can fix it by improving the vt switching dance - logind should have
all the information it needs.

While pondering all this I'm also wondering wheter we should have a
SWITCH_MASTER ioctl to allow race-free master status handover. But
that's for another day.

v2: Somehow forgot to cc all the fbdev people.

v3: Fix typo Alex spotted.
Reviewed-by: NAlex Deucher <alexander.deucher@amd.com>
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=208179
Cc: shlomo@fastmail.com
Reported-and-Tested-by: shlomo@fastmail.com
Cc: Michel Dänzer <michel@daenzer.net>
Fixes: 64914da2 ("drm/fbdev-helper: don't force restores")
Cc: Noralf Trønnes <noralf@tronnes.org>
Cc: Thomas Zimmermann <tzimmermann@suse.de>
Cc: Daniel Vetter <daniel.vetter@intel.com>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Maxime Ripard <mripard@kernel.org>
Cc: David Airlie <airlied@linux.ie>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: dri-devel@lists.freedesktop.org
Cc: <stable@vger.kernel.org> # v5.7+
Cc: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Nathan Chancellor <natechancellor@gmail.com>
Cc: Qiujun Huang <hqjagain@gmail.com>
Cc: Peter Rosin <peda@axentia.se>
Cc: linux-fbdev@vger.kernel.org
Signed-off-by: NDaniel Vetter <daniel.vetter@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200624092910.3280448-1-daniel.vetter@ffwll.ch

With earlier commits, the API no longer discards the const-ness of the
sysrq_key_op. As such we can add the notation.

Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jiri Slaby <jslaby@suse.com>
Cc: linux-kernel@vger.kernel.org
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Maxime Ripard <mripard@kernel.org>
Cc: Thomas Zimmermann <tzimmermann@suse.de>
Cc: dri-devel@lists.freedesktop.org
Reviewed-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Acked-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: NEmil Velikov <emil.l.velikov@gmail.com>
Link: https://lore.kernel.org/r/20200513214351.2138580-8-emil.l.velikov@gmail.comSigned-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Generic fbdev emulation is a DRM client. Drivers should invoke the
setup function, but not depend on its success. Hence remove the return
value.

v3:
	* document stricter requirements for call sequence
v2:
	* warn if fbdev device has not been registered yet
	* document the new behavior
	* convert the existing warning to the new dev_ interface
Signed-off-by: NThomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: NSam Ravnborg <sam@ravnborg.org>
Reviewed-by: NNoralf Trønnes <noralf@tronnes.org>
Acked-by: NSam Ravnborg <sam@ravnborg.org>
Acked-by: NGerd Hoffmann <kraxel@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200408082641.590-11-tzimmermann@suse.de

Currently drivers using drm_fbdev_generic_setup() end up with a single
empty aperture in their fb_info struct.

Not having the proper info in the apertures list causes
register_framebuffer to not remove conflicting framebuffers,
which some drivers currently workaround by manually calling
drm_fb_helper_remove_conflicting_pci_framebuffers().

Add a TODO as a reminder that we need to fix this.
Signed-off-by: NHans de Goede <hdegoede@redhat.com>
Reviewed-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20200326151009.102377-1-hdegoede@redhat.com

The max connector argument for drm_fb_helper_init() isn't used anymore
hence remove it.

All the drm_fb_helper_init() calls are modified with below sementic
patch.

@@
expression E1, E2, E3;
@@
-  drm_fb_helper_init(E1,E2, E3)
+  drm_fb_helper_init(E1,E2)
Signed-off-by: NPankaj Bharadiya <pankaj.laxminarayan.bharadiya@intel.com>
Reviewed-by: NEmil Velikov <emil.velikov@collabora.com>
Reviewed-by: NThomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: NAlex Deucher <alexander.deucher@amd.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20200305120434.111091-2-pankaj.laxminarayan.bharadiya@intel.com

Plus extend the kerneldoc a bit to explain how this should be used.
With the previous patch to drop the force restore the main user of
this function is not emphasis on the "I hold the internal master lock
already" aspect, so rename the function to match.

Suggested by Noralf.

Cc: Noralf Trønnes <noralf@tronnes.org>
Reviewed-by: NNoralf Trønnes <noralf@tronnes.org>
Tested-by: NThomas Zimmermann <tzimmermann@suse.de>
Acked-by: NThomas Zimmermann <tzimmermann@suse.de>
Signed-off-by: NDaniel Vetter <daniel.vetter@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200204150146.2006481-4-daniel.vetter@ffwll.ch

Instead check for master status, in case we've raced.

This is the last exception to the general rule that we restore fbcon
only when there's no master active. Compositors are supposed to drop
their master status before they switch to a different console back to
text mode (or just switch to text mode directly, without a vt switch).

This is known to break some subtests of kms_fbcon_fbt in igt, but they're
just wrong - it does a graphics/text mode switch for the vt without
updating the master status.

Also add a comment to the drm_client->restore hook that this is expected
going forward from all clients (there's currently just one).

v2: Also drop the force in pan_display

v3: Restore the _force to pan_display, this actually means _locked in that
path. Spotted by Noralf.

Cc: Noralf Trønnes <noralf@tronnes.org>
Reviewed-by: NNoralf Trønnes <noralf@tronnes.org>
Tested-by: NThomas Zimmermann <tzimmermann@suse.de>
Acked-by: NThomas Zimmermann <tzimmermann@suse.de>
Signed-off-by: NDaniel Vetter <daniel.vetter@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200204150146.2006481-3-daniel.vetter@ffwll.ch

When userspace requests a video mode parameter value that is not
supported, frame buffer device drivers should round it up to a supported
value, if possible, instead of just rejecting it.  This allows
applications to quickly scan for supported video modes.

Currently this rule is not followed for the number of bits per pixel,
causing e.g. "fbset -depth N" to fail, if N is smaller than the current
number of bits per pixel.

Fix this by returning an error only if bits per pixel is too large, and
setting it to the current value otherwise.

See also Documentation/fb/framebuffer.rst, Section 2 (Programmer's View
of /dev/fb*").

Fixes: 865afb11 ("drm/fb-helper: reject any changes to the fbdev")
Cc: stable@vger.kernel.org
Signed-off-by: NGeert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20191230132734.4538-1-geert+renesas@glider.be

DRM Fb driver expects multiple CRTCs if it sees connector->has_tile
is set, but we need to handle tile support and look for multiple CRTCs
only for the modes that match the tile size. The other modes should
be able to be displayed without tile support or uisng single CRTC.

This patch adds the check to match the tile size with requested mode
to handle the tile support.

Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Jani Nikula <jani.nikula@intel.com>
Cc: Dave Airlie <airlied@redhat.com>
Signed-off-by: NManasi Navare <manasi.d.navare@intel.com>
Reviewed-by: NDave Airlie <airlied@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191211212433.18185-1-manasi.d.navare@intel.com

Prefer drm_dbg_kms(), drm_info(), and drm_err() over all other
logging. This is about KMS so switch to the KMS category while at it.
Reviewed-by: NSam Ravnborg <sam@ravnborg.org>
Signed-off-by: NJani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191210123050.8799-3-jani.nikula@intel.com

Now that the fbops member of struct fb_info is const, we can start
making the ops const as well.

Cc: dri-devel@lists.freedesktop.org
Reviewed-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: NJani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/59b43629ac60031c5bbf961d8c49695019bc9c6f.1575390740.git.jani.nikula@intel.com

Deferred IO now preserves the fb_ops.

v2: Remove the no-op vfree, drop a local var  (Noralf)

Cc: Noralf Trønnes <noralf@tronnes.org>
Cc: dri-devel@lists.freedesktop.org
Reviewed-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Reviewed-by: NNoralf Trønnes <noralf@tronnes.org>
Signed-off-by: NJani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/1eae0b23d4724d5702b886b6a061ec8219eb9284.1575022735.git.jani.nikula@intel.com

There are no callers of drm_fb_helper_unlink_fbi() left. Remove the
function.
Signed-off-by: NThomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: NNoralf Trønnes <noralf@tronnes.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20191114125106.28347-3-tzimmermann@suse.de