• Luis R. Rodriguez's avatar
    x86/mm/mtrr, pat: Document Write Combining MTRR type effects on PAT / non-PAT pages · 2f9e8973
    Luis R. Rodriguez authored
    As part of the effort to phase out MTRR use document
    write-combining MTRR effects on pages with different non-PAT
    page attributes flags and different PAT entry values. Extend
    arch_phys_wc_add() documentation to clarify power of two sizes /
    boundary requirements as we phase out mtrr_add() use.
    Lastly hint towards ioremap_uc() for corner cases on device
    drivers working with devices with mixed regions where MTRR size
    requirements would otherwise not enable write-combining
    effective memory types.
    Signed-off-by: default avatarLuis R. Rodriguez <mcgrof@suse.com>
    Signed-off-by: default avatarBorislav Petkov <bp@suse.de>
    Cc: Andy Lutomirski <luto@amacapital.net>
    Cc: Antonino Daplas <adaplas@gmail.com>
    Cc: Borislav Petkov <bp@alien8.de>
    Cc: Brian Gerst <brgerst@gmail.com>
    Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
    Cc: Dave Airlie <airlied@redhat.com>
    Cc: Dave Hansen <dave.hansen@linux.intel.com>
    Cc: Davidlohr Bueso <dbueso@suse.de>
    Cc: Denys Vlasenko <dvlasenk@redhat.com>
    Cc: H. Peter Anvin <hpa@zytor.com>
    Cc: Jean-Christophe Plagniol-Villard <plagnioj@jcrosoft.com>
    Cc: Jonathan Corbet <corbet@lwn.net>
    Cc: Juergen Gross <jgross@suse.com>
    Cc: Linus Torvalds <torvalds@linux-foundation.org>
    Cc: Mel Gorman <mgorman@suse.de>
    Cc: Peter Zijlstra <peterz@infradead.org>
    Cc: Suresh Siddha <sbsiddha@gmail.com>
    Cc: Thomas Gleixner <tglx@linutronix.de>
    Cc: Tomi Valkeinen <tomi.valkeinen@ti.com>
    Cc: Ville Syrjälä <syrjala@sci.fi>
    Cc: Vlastimil Babka <vbabka@suse.cz>
    Cc: linux-fbdev@vger.kernel.org
    Link: http://lkml.kernel.org/r/1430343851-967-3-git-send-email-mcgrof@do-not-panic.com
    Link: http://lkml.kernel.org/r/1432628901-18044-10-git-send-email-bp@alien8.deSigned-off-by: default avatarIngo Molnar <mingo@kernel.org>
mtrr.txt 10.8 KB