[PATCH 1/4] docs: fb: Remove framebuffer scrollback boot option

From: Bhaskar Chowdhury
Date: Thu Sep 17 2020 - 06:32:43 EST

In commit 50145474f6ef ("fbcon: remove soft scrollback code"), the
framebuffer scrollback mode was removed, but the documentation was not
updated. Properly update the documentation by removing the option that
is no longer present, and update the section numbering because of the

Signed-off-by: Bhaskar Chowdhury <unixbhaskar@xxxxxxxxx>
Change since V3:
Following the suggestions from Willy and Greg.In this version remove the not
relevant commit hash and messages from the changelog.
Documentation/fb/fbcon.rst | 21 +++++++--------------
1 file changed, 7 insertions(+), 14 deletions(-)

diff --git a/Documentation/fb/fbcon.rst b/Documentation/fb/fbcon.rst
index e57a3d1d085a..328f6980698c 100644
--- a/Documentation/fb/fbcon.rst
+++ b/Documentation/fb/fbcon.rst
@@ -87,15 +87,8 @@ C. Boot options
Note, not all drivers can handle font with widths not divisible by 8,
such as vga16fb.

-2. fbcon=scrollback:<value>[k]

- The scrollback buffer is memory that is used to preserve display
- contents that has already scrolled past your view. This is accessed
- by using the Shift-PageUp key combination. The value 'value' is any
- integer. It defaults to 32KB. The 'k' suffix is optional, and will
- multiply the 'value' by 1024.
-3. fbcon=map:<0123>
+2. fbcon=map:<0123>

This is an interesting option. It tells which driver gets mapped to
which console. The value '0123' is a sequence that gets repeated until
@@ -116,7 +109,7 @@ C. Boot options
Later on, when you want to map the console the to the framebuffer
device, you can use the con2fbmap utility.

-4. fbcon=vc:<n1>-<n2>
+3. fbcon=vc:<n1>-<n2>

This option tells fbcon to take over only a range of consoles as
specified by the values 'n1' and 'n2'. The rest of the consoles
@@ -127,7 +120,7 @@ C. Boot options
is typically located on the same video card. Thus, the consoles that
are controlled by the VGA console will be garbled.

-5. fbcon=rotate:<n>
+4. fbcon=rotate:<n>

This option changes the orientation angle of the console display. The
value 'n' accepts the following:
@@ -152,21 +145,21 @@ C. Boot options
Actually, the underlying fb driver is totally ignorant of console

-6. fbcon=margin:<color>
+5. fbcon=margin:<color>

This option specifies the color of the margins. The margins are the
leftover area at the right and the bottom of the screen that are not
used by text. By default, this area will be black. The 'color' value
is an integer number that depends on the framebuffer driver being used.

-7. fbcon=nodefer
+6. fbcon=nodefer

If the kernel is compiled with deferred fbcon takeover support, normally
the framebuffer contents, left in place by the firmware/bootloader, will
be preserved until there actually is some text is output to the console.
This option causes fbcon to bind immediately to the fbdev device.

-8. fbcon=logo-pos:<location>
+7. fbcon=logo-pos:<location>

The only possible 'location' is 'center' (without quotes), and when
given, the bootup logo is moved from the default top-left corner
@@ -174,7 +167,7 @@ C. Boot options
displayed due to multiple CPUs, the collected line of logos is moved
as a whole.

-9. fbcon=logo-count:<n>
+8. fbcon=logo-count:<n>

The value 'n' overrides the number of bootup logos. 0 disables the
logo, and -1 gives the default which is the number of online CPUs.