fbcon: Fix accelerated fbdev scrolling while logo is still shown
authorHelge Deller <deller@gmx.de>
Thu, 2 Jun 2022 20:08:38 +0000 (22:08 +0200)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Wed, 17 Aug 2022 12:22:51 +0000 (14:22 +0200)
commit 3866cba87dcd0162fb41e9b3b653d0af68fad5ec upstream.

There is no need to directly skip over to the SCROLL_REDRAW case while
the logo is still shown.

When using DRM, this change has no effect because the code will reach
the SCROLL_REDRAW case immediately anyway.

But if you run an accelerated fbdev driver and have
FRAMEBUFFER_CONSOLE_LEGACY_ACCELERATION enabled, console scrolling is
slowed down by factors so that it feels as if you use a 9600 baud
terminal.

So, drop those unnecessary checks and speed up fbdev console
acceleration during bootup.

Cc: stable@vger.kernel.org # v5.10+
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Helge Deller <deller@gmx.de>
Link: https://patchwork.freedesktop.org/patch/msgid/YpkYxk7wsBPx3po+@p100
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
drivers/video/fbdev/core/fbcon.c

index c1362c1..fb02105 100644 (file)
@@ -1706,8 +1706,6 @@ static bool fbcon_scroll(struct vc_data *vc, unsigned int t, unsigned int b,
        case SM_UP:
                if (count > vc->vc_rows)        /* Maximum realistic size */
                        count = vc->vc_rows;
-               if (logo_shown >= 0)
-                       goto redraw_up;
                switch (fb_scrollmode(p)) {
                case SCROLL_MOVE:
                        fbcon_redraw_blit(vc, info, p, t, b - t - count,
@@ -1796,8 +1794,6 @@ static bool fbcon_scroll(struct vc_data *vc, unsigned int t, unsigned int b,
        case SM_DOWN:
                if (count > vc->vc_rows)        /* Maximum realistic size */
                        count = vc->vc_rows;
-               if (logo_shown >= 0)
-                       goto redraw_down;
                switch (fb_scrollmode(p)) {
                case SCROLL_MOVE:
                        fbcon_redraw_blit(vc, info, p, b - 1, b - t - count,