Documentation: x86: convert usb-legacy-support.txt to reST

This converts the plain text documentation to reStructuredText format and
add it to Sphinx TOC tree. No essential content change.

Signed-off-by: Changbin Du <changbin.du@gmail.com>
Reviewed-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

diff --git a/Documentation/x86/index.rst b/Documentation/x86/index.rst
index 4535570..3eb0334 100644 (file)
--- a/Documentation/x86/index.rst
+++ b/Documentation/x86/index.rst
@@ -25,3 +25,4 @@ x86-specific Documentation
    pti
    microcode
    resctrl_ui
+   usb-legacy-support

diff --git a/Documentation/x86/usb-legacy-support.rst b/Documentation/x86/usb-legacy-support.rst
new file mode 100644 (file)
index 0000000..e01c08b
--- /dev/null
+++ b/Documentation/x86/usb-legacy-support.rst
@@ -0,0 +1,50 @@
+
+.. SPDX-License-Identifier: GPL-2.0
+
+==================
+USB Legacy support
+==================
+
+:Author: Vojtech Pavlik <vojtech@suse.cz>, January 2004
+
+
+Also known as "USB Keyboard" or "USB Mouse support" in the BIOS Setup is a
+feature that allows one to use the USB mouse and keyboard as if they were
+their classic PS/2 counterparts.  This means one can use an USB keyboard to
+type in LILO for example.
+
+It has several drawbacks, though:
+
+1) On some machines, the emulated PS/2 mouse takes over even when no USB
+   mouse is present and a real PS/2 mouse is present.  In that case the extra
+   features (wheel, extra buttons, touchpad mode) of the real PS/2 mouse may
+   not be available.
+
+2) If CONFIG_HIGHMEM64G is enabled, the PS/2 mouse emulation can cause
+   system crashes, because the SMM BIOS is not expecting to be in PAE mode.
+   The Intel E7505 is a typical machine where this happens.
+
+3) If AMD64 64-bit mode is enabled, again system crashes often happen,
+   because the SMM BIOS isn't expecting the CPU to be in 64-bit mode.  The
+   BIOS manufacturers only test with Windows, and Windows doesn't do 64-bit
+   yet.
+
+Solutions:
+
+Problem 1)
+  can be solved by loading the USB drivers prior to loading the
+  PS/2 mouse driver. Since the PS/2 mouse driver is in 2.6 compiled into
+  the kernel unconditionally, this means the USB drivers need to be
+  compiled-in, too.
+
+Problem 2)
+  can currently only be solved by either disabling HIGHMEM64G
+  in the kernel config or USB Legacy support in the BIOS. A BIOS update
+  could help, but so far no such update exists.
+
+Problem 3)
+  is usually fixed by a BIOS update. Check the board
+  manufacturers web site. If an update is not available, disable USB
+  Legacy support in the BIOS. If this alone doesn't help, try also adding
+  idle=poll on the kernel command line. The BIOS may be entering the SMM
+  on the HLT instruction as well.

diff --git a/Documentation/x86/usb-legacy-support.txt b/Documentation/x86/usb-legacy-support.txt
deleted file mode 100644 (file)
index 1894cdf..0000000
--- a/Documentation/x86/usb-legacy-support.txt
+++ /dev/null
@@ -1,44 +0,0 @@
-USB Legacy support
-~~~~~~~~~~~~~~~~~~
-
-Vojtech Pavlik <vojtech@suse.cz>, January 2004
-
-
-Also known as "USB Keyboard" or "USB Mouse support" in the BIOS Setup is a
-feature that allows one to use the USB mouse and keyboard as if they were
-their classic PS/2 counterparts.  This means one can use an USB keyboard to
-type in LILO for example.
-
-It has several drawbacks, though:
-
-1) On some machines, the emulated PS/2 mouse takes over even when no USB
-   mouse is present and a real PS/2 mouse is present.  In that case the extra
-   features (wheel, extra buttons, touchpad mode) of the real PS/2 mouse may
-   not be available.
-
-2) If CONFIG_HIGHMEM64G is enabled, the PS/2 mouse emulation can cause
-   system crashes, because the SMM BIOS is not expecting to be in PAE mode.
-   The Intel E7505 is a typical machine where this happens.
-
-3) If AMD64 64-bit mode is enabled, again system crashes often happen,
-   because the SMM BIOS isn't expecting the CPU to be in 64-bit mode.  The
-   BIOS manufacturers only test with Windows, and Windows doesn't do 64-bit
-   yet.
-
-Solutions:
-
-Problem 1) can be solved by loading the USB drivers prior to loading the
-PS/2 mouse driver. Since the PS/2 mouse driver is in 2.6 compiled into
-the kernel unconditionally, this means the USB drivers need to be
-compiled-in, too.
-
-Problem 2) can currently only be solved by either disabling HIGHMEM64G
-in the kernel config or USB Legacy support in the BIOS. A BIOS update
-could help, but so far no such update exists.
-
-Problem 3) is usually fixed by a BIOS update. Check the board
-manufacturers web site. If an update is not available, disable USB
-Legacy support in the BIOS. If this alone doesn't help, try also adding
-idle=poll on the kernel command line. The BIOS may be entering the SMM
-on the HLT instruction as well.
-