fbcon: Use correct erase colour for clearing in fbcon

The erase colour calculation for fbcon clearing should use get_color instead
of attr_col_ec, like everything else. The latter is similar but is

fbcon: Use correct erase colour for clearing in fbcon

The erase colour calculation for fbcon clearing should use get_color instead
of attr_col_ec, like everything else. The latter is similar but is not correct.
For example it's missing the depth dependent remapping and doesn't care about
blanking.

The problem can be reproduced by setting up the background colour to grey
(vt.color=0x70) and having an fbcon console set to 2bpp (4 shades of gray).
Now the background attribute should be 1 (dark gray) on the console.

If the screen is scrolled when pressing enter in a shell prompt at the bottom
line then the new line is cleared using colour 7 instead of 1. That's not
something fillrect likes (at 2bbp it expect 0-3) so the result is interesting.

This patch switches to get_color with vc_video_erase_char to determine the
erase colour from attr_col_ec. That makes the latter function redundant as
no other users were left.

Use correct erase colour for clearing in fbcon

Signed-off-by: Zsolt Kajtar <[email protected]>
Signed-off-by: Helge Deller <[email protected]>

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tty: vt: remove CM_* constants

There is no difference between CM_MOVE and CM_DRAW. Either of them
enables the cursor. CM_ERASE then disables cursor.

So get rid of all of them and use simple "bool e

tty: vt: remove CM_* constants

There is no difference between CM_MOVE and CM_DRAW. Either of them
enables the cursor. CM_ERASE then disables cursor.

So get rid of all of them and use simple "bool enable".

Note that this propagates down to the fbcon code.

And document the hook.

Signed-off-by: "Jiri Slaby (SUSE)" <[email protected]>
Cc: Helge Deller <[email protected]>
Cc: "James E.J. Bottomley" <[email protected]>
Cc: Daniel Vetter <[email protected]>
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Tested-by: Helge Deller <[email protected]> # parisc STI console
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>

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fbcon: Replace FBCON_FLAGS_INIT with a boolean

It's only one flag and slightly tidier code.

Acked-by: Thomas Zimmermann <[email protected]>
Acked-by: Sam Ravnborg <[email protected]>
Signed-off-by

fbcon: Replace FBCON_FLAGS_INIT with a boolean

It's only one flag and slightly tidier code.

Acked-by: Thomas Zimmermann <[email protected]>
Acked-by: Sam Ravnborg <[email protected]>
Signed-off-by: Daniel Vetter <[email protected]>
Cc: Daniel Vetter <[email protected]>
Cc: Tetsuo Handa <[email protected]>
Cc: Greg Kroah-Hartman <[email protected]>
Cc: Du Cheng <[email protected]>
Cc: Thomas Zimmermann <[email protected]>
Cc: Claudio Suarez <[email protected]>
Link: https://patchwork.freedesktop.org/patch/msgid/[email protected]

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fbcon: Use delayed work for cursor

Allows us to delete a bunch of hand-rolled stuff using a timer plus a
separate work). Also to simplify the code we initialize the
cursor_work completely when we al

fbcon: Use delayed work for cursor

Allows us to delete a bunch of hand-rolled stuff using a timer plus a
separate work). Also to simplify the code we initialize the
cursor_work completely when we allocate the fbcon_ops structure,
instead of trying to cope with console re-initialization.

The motiviation here is that fbcon code stops using the fb_info.queue,
which helps with locking issues around cleanup and all that in a later
patch.

Also note that this allows us to ditch the hand-rolled work cleanup in
fbcon_exit - we already call fbcon_del_cursor_timer, which takes care
of everything. Plus this was racy anyway.

v2:
- Only INIT_DELAYED_WORK when kzalloc succeeded (Tetsuo)
- Explain that we replace both the timer and a work with the combined
delayed_work (Javier)

Reviewed-by: Javier Martinez Canillas <[email protected]>
Acked-by: Thomas Zimmermann <[email protected]>
Signed-off-by: Daniel Vetter <[email protected]>
Cc: Daniel Vetter <[email protected]>
Cc: Claudio Suarez <[email protected]>
Cc: Du Cheng <[email protected]>
Cc: Thomas Zimmermann <[email protected]>
Cc: Greg Kroah-Hartman <[email protected]>
Cc: Tetsuo Handa <[email protected]>
Link: https://patchwork.freedesktop.org/patch/msgid/[email protected]

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fbcon: Add option to enable legacy hardware acceleration

Add a config option CONFIG_FRAMEBUFFER_CONSOLE_LEGACY_ACCELERATION to
enable bitblt and fillrect hardware acceleration in the framebuffer
con

fbcon: Add option to enable legacy hardware acceleration

Add a config option CONFIG_FRAMEBUFFER_CONSOLE_LEGACY_ACCELERATION to
enable bitblt and fillrect hardware acceleration in the framebuffer
console. If disabled, such acceleration will not be used, even if it is
supported by the graphics hardware driver.

If you plan to use DRM as your main graphics output system, you should
disable this option since it will prevent compiling in code which isn't
used later on when DRM takes over.

For all other configurations, e.g. if none of your graphic cards support
DRM (yet), DRM isn't available for your architecture, or you can't be
sure that the graphic card in the target system will support DRM, you
most likely want to enable this option.

In the non-accelerated case (e.g. when DRM is used), the inlined
fb_scrollmode() function is hardcoded to return SCROLL_REDRAW and as such the
compiler is able to optimize much unneccesary code away.

In this v3 patch version I additionally changed the GETVYRES() and GETVXRES()
macros to take a pointer to the fbcon_display struct. This fixes the build when
console rotation is enabled and helps the compiler again to optimize out code.

Signed-off-by: Helge Deller <[email protected]>
Cc: [email protected] # v5.10+
Signed-off-by: Helge Deller <[email protected]>
Signed-off-by: Daniel Vetter <[email protected]>
Link: https://patchwork.freedesktop.org/patch/msgid/[email protected]

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Revert "fbdev: Garbage collect fbdev scrolling acceleration, part 1 (from TODO list)"

This reverts commit b3ec8cdf457e5e63d396fe1346cc788cf7c1b578.

Revert the second (of 2) commits which disabled s

Revert "fbdev: Garbage collect fbdev scrolling acceleration, part 1 (from TODO list)"

This reverts commit b3ec8cdf457e5e63d396fe1346cc788cf7c1b578.

Revert the second (of 2) commits which disabled scrolling acceleration
in fbcon/fbdev. It introduced a regression for fbdev-supported graphic
cards because of the performance penalty by doing screen scrolling by
software instead of using the existing graphic card 2D hardware
acceleration.

Console scrolling acceleration was disabled by dropping code which
checked at runtime the driver hardware capabilities for the
BINFO_HWACCEL_COPYAREA or FBINFO_HWACCEL_FILLRECT flags and if set, it
enabled scrollmode SCROLL_MOVE which uses hardware acceleration to move
screen contents. After dropping those checks scrollmode was hard-wired
to SCROLL_REDRAW instead, which forces all graphic cards to redraw every
character at the new screen position when scrolling.

This change effectively disabled all hardware-based scrolling acceleration for
ALL drivers, because now all kind of 2D hardware acceleration (bitblt,
fillrect) in the drivers isn't used any longer.

The original commit message mentions that only 3 DRM drivers (nouveau, omapdrm
and gma500) used hardware acceleration in the past and thus code for checking
and using scrolling acceleration is obsolete.

This statement is NOT TRUE, because beside the DRM drivers there are around 35
other fbdev drivers which depend on fbdev/fbcon and still provide hardware
acceleration for fbdev/fbcon.

The original commit message also states that syzbot found lots of bugs in fbcon
and thus it's "often the solution to just delete code and remove features".
This is true, and the bugs - which actually affected all users of fbcon,
including DRM - were fixed, or code was dropped like e.g. the support for
software scrollback in vgacon (commit 973c096f6a85).

So to further analyze which bugs were found by syzbot, I've looked through all
patches in drivers/video which were tagged with syzbot or syzkaller back to
year 2005. The vast majority fixed the reported issues on a higher level, e.g.
when screen is to be resized, or when font size is to be changed. The few ones
which touched driver code fixed a real driver bug, e.g. by adding a check.

But NONE of those patches touched code of either the SCROLL_MOVE or the
SCROLL_REDRAW case.

That means, there was no real reason why SCROLL_MOVE had to be ripped-out and
just SCROLL_REDRAW had to be used instead. The only reason I can imagine so far
was that SCROLL_MOVE wasn't used by DRM and as such it was assumed that it
could go away. That argument completely missed the fact that SCROLL_MOVE is
still heavily used by fbdev (non-DRM) drivers.

Some people mention that using memcpy() instead of the hardware acceleration is
pretty much the same speed. But that's not true, at least not for older graphic
cards and machines where we see speed decreases by factor 10 and more and thus
this change leads to console responsiveness way worse than before.

That's why the original commit is to be reverted. By reverting we
reintroduce hardware-based scrolling acceleration and fix the
performance regression for fbdev drivers.

There isn't any impact on DRM when reverting those patches.

Signed-off-by: Helge Deller <[email protected]>
Acked-by: Geert Uytterhoeven <[email protected]>
Acked-by: Sven Schnelle <[email protected]>
Cc: [email protected] # v5.16+
Signed-off-by: Helge Deller <[email protected]>
Signed-off-by: Daniel Vetter <[email protected]>
Link: https://patchwork.freedesktop.org/patch/msgid/[email protected]

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fbdev: Garbage collect fbdev scrolling acceleration, part 1 (from TODO list)

Scroll acceleration is disabled in fbcon by hard-wiring
p->scrollmode = SCROLL_REDRAW. Remove the obsolete code in fbcon.

fbdev: Garbage collect fbdev scrolling acceleration, part 1 (from TODO list)

Scroll acceleration is disabled in fbcon by hard-wiring
p->scrollmode = SCROLL_REDRAW. Remove the obsolete code in fbcon.c
and fbdev/core/

Signed-off-by: Claudio Suarez <[email protected]>
Signed-off-by: Thomas Zimmermann <[email protected]>
Link: https://patchwork.freedesktop.org/patch/msgid/[email protected]

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fbdev, newport_con: Move FONT_EXTRA_WORDS macros into linux/font.h

drivers/video/console/newport_con.c is borrowing FONT_EXTRA_WORDS macros
from drivers/video/fbdev/core/fbcon.h. To keep things simp

fbdev, newport_con: Move FONT_EXTRA_WORDS macros into linux/font.h

drivers/video/console/newport_con.c is borrowing FONT_EXTRA_WORDS macros
from drivers/video/fbdev/core/fbcon.h. To keep things simple, move all
definitions into <linux/font.h>.

Since newport_con now uses four extra words, initialize the fourth word in
newport_set_font() properly.

Cc: [email protected]
Signed-off-by: Peilin Ye <[email protected]>
Reviewed-by: Greg Kroah-Hartman <[email protected]>
Signed-off-by: Daniel Vetter <[email protected]>
Link: https://patchwork.freedesktop.org/patch/msgid/7fb8bc9b0abc676ada6b7ac0e0bd443499357267.1600953813.git.yepeilin.cs@gmail.com

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fbcon: remove now unusued 'softback_lines' cursor() argument

Since the softscroll code got removed, this argument is always zero and
makes no sense any more.

Tested-by: Yuan Ming <yuanmingbuaa@gmai

fbcon: remove now unusued 'softback_lines' cursor() argument

Since the softscroll code got removed, this argument is always zero and
makes no sense any more.

Tested-by: Yuan Ming <[email protected]>
Tested-by: Willy Tarreau <[email protected]>
Reviewed-by: Greg Kroah-Hartman <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

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fbcon: s/struct display/struct fbcon_display/

This was formerly used in fbdev drivers (not sure why, predates most
git history), but now it's entirely an fbcon internal thing. Give it a
more specifi

fbcon: s/struct display/struct fbcon_display/

This was formerly used in fbdev drivers (not sure why, predates most
git history), but now it's entirely an fbcon internal thing. Give it a
more specific name.

Signed-off-by: Daniel Vetter <[email protected]>
Reviewed-by: Sam Ravnborg <[email protected]>
Reviewed-by: Maarten Lankhorst <[email protected]>
Cc: Bartlomiej Zolnierkiewicz <[email protected]>
Cc: Daniel Vetter <[email protected]>
Cc: Hans de Goede <[email protected]>
Cc: Greg Kroah-Hartman <[email protected]>
Cc: Kees Cook <[email protected]>
Cc: Prarit Bhargava <[email protected]>
Cc: Konstantin Khorenko <[email protected]>
Cc: Peter Rosin <[email protected]>
Cc: Yisheng Xie <[email protected]>
Link: https://patchwork.freedesktop.org/patch/msgid/[email protected]

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fbcon: Remove dmi quirk table

This is now all handled in the drivers and communicated through
fb_info.fbcon_rotate_hint.

Acked-by: Bartlomiej Zolnierkiewicz <[email protected]>
Signed-off-by

fbcon: Remove dmi quirk table

This is now all handled in the drivers and communicated through
fb_info.fbcon_rotate_hint.

Acked-by: Bartlomiej Zolnierkiewicz <[email protected]>
Signed-off-by: Hans de Goede <[email protected]>
Link: https://patchwork.freedesktop.org/patch/msgid/[email protected]

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video: fbdev: Convert timers to use timer_setup()

In preparation for unconditionally passing the struct timer_list pointer to
all timer callbacks, switch to using the new timer_setup() and from_time

video: fbdev: Convert timers to use timer_setup()

In preparation for unconditionally passing the struct timer_list pointer to
all timer callbacks, switch to using the new timer_setup() and from_timer()
to pass the timer pointer explicitly. One tracking pointer was added.

Signed-off-by: Kees Cook <[email protected]>
Cc: Benjamin Herrenschmidt <[email protected]>
Cc: Tomi Valkeinen <[email protected]>
Cc: David Lechner <[email protected]>
Cc: Daniel Vetter <[email protected]>
Cc: Sean Paul <[email protected]>
Cc: Jean Delvare <[email protected]>
Cc: Hans de Goede <[email protected]>
Cc: "Gustavo A. R. Silva" <[email protected]>
[b.zolnierkie: ported it over pxa3xx_gcu changes]
Signed-off-by: Bartlomiej Zolnierkiewicz <[email protected]>

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fbcon: add fbcon=margin:<color> command line option

This adds a new command line option to select the fbcon margin color.

The motivation for this is screens where black does not blend into the
phys

fbcon: add fbcon=margin:<color> command line option

This adds a new command line option to select the fbcon margin color.

The motivation for this is screens where black does not blend into the
physical surroundings of the screen. For example, using an LCD (not the
backlit kind), white text on a black background is hard to read, so
inverting the colors is preferred. However, when you do this, most of the
screen is filled with white but the margins are still filled with black.
This makes a big, black, backwards 'L' on the screen. By setting
fbcon=margin:7, the margins will be filled with white and the LCD looks as
expected.

Signed-off-by: David Lechner <[email protected]>
[b.zolnierkie: ported over fbcon changes]
Signed-off-by: Bartlomiej Zolnierkiewicz <[email protected]>

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video/console: Add dmi quirk table for x86 systems which need fbcon rotation

Some x86 clamshell design devices use portrait tablet screens and a
display engine which cannot rotate in hardware, so we

video/console: Add dmi quirk table for x86 systems which need fbcon rotation

Some x86 clamshell design devices use portrait tablet screens and a
display engine which cannot rotate in hardware, so we need to rotate
the fbcon to compensate.

This commit adds a DMI based quirk table which is initially populated with
4 such devices: The Asus T100HA, GPD Pocket, the GPD win and the I.T.Works
TW891, so that the console comes up in the right orientation on these
devices OOTB.

Unfortunately these (cheap) devices also typically have quite generic DMI
data, so we match on a combination of DMI data, screen resolution and a
list of known BIOS dates to avoid false positives.

Suggested-by: Jean Delvare <[email protected]>
Signed-off-by: Hans de Goede <[email protected]>
Reviewed-by: Jean Delvare <[email protected]>
[b.zolnierkie: ported over fbcon changes]
Signed-off-by: Bartlomiej Zolnierkiewicz <[email protected]>

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fbcon: Make fbcon a built-time depency for fbdev

There's a bunch of folks who're trying to make printk less
contended and faster, but there's a problem: printk uses the
console_lock, and the console

fbcon: Make fbcon a built-time depency for fbdev

There's a bunch of folks who're trying to make printk less
contended and faster, but there's a problem: printk uses the
console_lock, and the console lock has become the BKL for all things
fbdev/fbcon, which in turn pulled in half the drm subsystem under that
lock. That's awkward.

There reasons for that is probably just a historical accident:

- fbcon is a runtime option of fbdev, i.e. at runtime you can pick
whether your fbdev driver instances are used as kernel consoles.
Unfortunately this wasn't implemented with some module option, but
through some module loading magic: As long as you don't load
fbcon.ko, there's no fbdev console support, but loading it (in any
order wrt fbdev drivers) will create console instances for all fbdev
drivers.

- This was implemented through a notifier chain. fbcon.ko enumerates
all fbdev instances at load time and also registers itself as
listener in the fbdev notifier. The fbdev core tries to register new
fbdev instances with fbcon using the notifier.

- On top of that the modifier chain is also used at runtime by the
fbdev subsystem to e.g. control backlights for panels.

- The problem is that the notifier puts a mutex locking context
between fbdev and fbcon, which mixes up the locking contexts for
both the runtime usage and the register time usage to notify fbcon.
And at runtime fbcon (through the fbdev core) might call into the
notifier from a printk critical section while console_lock is held.

- This means console_lock must be an outer lock for the entire fbdev
subsystem, which also means it must be acquired when registering a
new framebuffer driver as the outermost lock since we might call
into fbcon (through the notifier) which would result in a locking
inversion if fbcon would acquire the console_lock from its notifier
callback (which it needs to register the console).

- console_lock can be held anywhere, since printk can be called
anywhere, and through the above story, plus drm/kms being an fbdev
driver, we pull in a shocking amount of locking hiercharchy
underneath the console_lock. Which makes cleaning up printk really
hard (not even splitting console_lock into an rwsem is all that
useful due to this).

There's various ways to address this, but the cleanest would be to
make fbcon a compile-time option, where fbdev directly calls the fbcon
register functions from register_framebuffer, or dummy static inline
versions if fbcon is disabled. Maybe augmented with a runtime knob to
disable fbcon, if that's needed (for debugging perhaps).

But this could break some users who rely on the magic "loading
fbcon.ko enables/disables fbdev framebuffers at runtime" thing, even
if that's unlikely. Hence we must be careful:

1. Create a compile-time dependency between fbcon and fbdev in the
least minimal way. This is what this patch does.

2. Wait at least 1 year to give possible users time to scream about
how we broke their setup. Unlikely, since all distros make fbcon
compile-in, and embedded platforms only compile stuff they know they
need anyway. But still.

3. Convert the notifier to direct functions calls, with dummy static
inlines if fbcon is disabled. We'll still need the fb notifier for the
other uses (like backlights), but we can probably move it into the fb
core (atm it must be built-into vmlinux).

4. Push console_lock down the call-chain, until it is down in
console_register again.

5. Finally start to clean up and rework the printk/console locking.

For context of this saga see

commit 50e244cc793d511b86adea24972f3a7264cae114
Author: Alan Cox <[email protected]>
Date: Fri Jan 25 10:28:15 2013 +1000

fb: rework locking to fix lock ordering on takeover

plus the pile of commits on top that tried to make this all work
without terminally upsetting lockdep. We've uncovered all this when
console_lock lockdep annotations where added in

commit daee779718a319ff9f83e1ba3339334ac650bb22
Author: Daniel Vetter <[email protected]>
Date: Sat Sep 22 19:52:11 2012 +0200

console: implement lockdep support for console_lock

On the patch itself:
- Switch CONFIG_FRAMEBUFFER_CONSOLE to be a boolean, using the overall
CONFIG_FB tristate to decided whether it should be a module or
built-in.

- At first I thought I could force the build depency with just a dummy
symbol that fbcon.ko exports and fb.ko uses. But that leads to a
module depency cycle (it works fine when built-in).

Since this tight binding is the entire goal the simplest solution is
to move all the fbcon modules (and there's a bunch of optinal
source-files which are each modules of their own, for no good
reason) into the overall fb.ko core module. That's a bit more than
what I would have liked to do in this patch, but oh well.

Signed-off-by: Daniel Vetter <[email protected]>
Cc: Alan Cox <[email protected]>
Cc: Sergey Senozhatsky <[email protected]>
Cc: Steven Rostedt <[email protected]>
Reviewed-by: Sean Paul <[email protected]>
Signed-off-by: Bartlomiej Zolnierkiewicz <[email protected]>

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