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| author | Andy Lutomirski <luto@amacapital.net> | 2013-05-13 23:58:46 +0000 |
|---|---|---|
| committer | Dave Airlie <airlied@redhat.com> | 2013-05-31 13:37:36 +1000 |
| commit | 63e28a7a5ffce59b645ca9cbcc01e1e8be56bd75 (patch) | |
| tree | 9f1772e41599f71bda18c71cc78480d7576e1b73 /Documentation | |
| parent | 07ebea251d08ae851d501f7402359f053d038862 (diff) | |
| download | lwn-63e28a7a5ffce59b645ca9cbcc01e1e8be56bd75.tar.gz lwn-63e28a7a5ffce59b645ca9cbcc01e1e8be56bd75.zip | |
uvesafb: Clean up MTRR code
The old code allowed very strange memory types. Now it works like
all the other video drivers: ioremap_wc is used unconditionally,
and MTRRs are set if PAT is unavailable (unless MTRR is disabled
by a module parameter).
UC, WB, and WT support is gone. If there are MTRR conflicts that prevent
addition of a WC MTRR, adding a non-conflicting MTRR is pointless; it's
better to just turn off MTRR support entirely.
As an added bonus, any MTRR added is freed on unload.
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Signed-off-by: Dave Airlie <airlied@redhat.com>
Diffstat (limited to 'Documentation')
| -rw-r--r-- | Documentation/fb/uvesafb.txt | 16 |
1 files changed, 5 insertions, 11 deletions
diff --git a/Documentation/fb/uvesafb.txt b/Documentation/fb/uvesafb.txt index eefdd91d298a..f6362d88763b 100644 --- a/Documentation/fb/uvesafb.txt +++ b/Documentation/fb/uvesafb.txt @@ -81,17 +81,11 @@ pmipal Use the protected mode interface for palette changes. mtrr:n Setup memory type range registers for the framebuffer where n: - 0 - disabled (equivalent to nomtrr) (default) - 1 - uncachable - 2 - write-back - 3 - write-combining - 4 - write-through - - If you see the following in dmesg, choose the type that matches - the old one. In this example, use "mtrr:2". -... -mtrr: type mismatch for e0000000,8000000 old: write-back new: write-combining -... + 0 - disabled (equivalent to nomtrr) + 3 - write-combining (default) + + Values other than 0 and 3 will result in a warning and will be + treated just like 3. nomtrr Do not use memory type range registers. |