On Fri, Mar 20, 2015 at 4:18 PM, Luis R. Rodriguez <[email protected]> wrote: > The same area used for ioremap() is used for the MTRR area. > Convert the driver from using the x86 specific MTRR code to > the architecture agnostic arch_phys_wc_add(). arch_phys_wc_add() > will avoid MTRR if write-combining is available, in order to > take advantage of that also ensure the ioremap'd area is requested > as write-combining. > > There are a few motivations for this: > > a) Take advantage of PAT when available > > b) Help bury MTRR code away, MTRR is architecture specific and on > x86 its replaced by PAT > > c) Help with the goal of eventually using _PAGE_CACHE_UC over > _PAGE_CACHE_UC_MINUS on x86 on ioremap_nocache() (de33c442e) > > The conversion done is expressed by the following Coccinelle > SmPL patch, it additionally required manual intervention to > address all the #ifdery and removal of redundant things which > arch_phys_wc_add() already addresses such as verbose message > about when MTRR fails and doing nothing when we didn't get > an MTRR. > > @ mtrr_found @ > expression index, base, size; > @@ > > -index = mtrr_add(base, size, MTRR_TYPE_WRCOMB, 1); > +index = arch_phys_wc_add(base, size); > > @ mtrr_rm depends on mtrr_found @ > expression mtrr_found.index, mtrr_found.base, mtrr_found.size; > @@ > > -mtrr_del(index, base, size); > +arch_phys_wc_del(index); > > @ mtrr_rm_zero_arg depends on mtrr_found @ > expression mtrr_found.index; > @@ > > -mtrr_del(index, 0, 0); > +arch_phys_wc_del(index); > > @ mtrr_rm_fb_info depends on mtrr_found @ > struct fb_info *info; > expression mtrr_found.index; > @@ > > -mtrr_del(index, info->fix.smem_start, info->fix.smem_len); > +arch_phys_wc_del(index); > > @ ioremap_replace_nocache depends on mtrr_found @ > struct fb_info *info; > expression base, size; > @@ > > -info->screen_base = ioremap_nocache(base, size); > +info->screen_base = ioremap_wc(base, size); > > @ ioremap_replace_default depends on mtrr_found @ > struct fb_info *info; > expression base, size; > @@ > > -info->screen_base = ioremap(base, size); > +info->screen_base = ioremap_wc(base, size); > > Generated-by: Coccinelle SmPL > Cc: Suresh Siddha <[email protected]> > Cc: Venkatesh Pallipadi <[email protected]> > Cc: Ingo Molnar <[email protected]> > Cc: Thomas Gleixner <[email protected]> > Cc: Juergen Gross <[email protected]> > Cc: Daniel Vetter <[email protected]> > Cc: Andy Lutomirski <[email protected]> > Cc: Dave Airlie <[email protected]> > Cc: Antonino Daplas <[email protected]> > Cc: Jean-Christophe Plagniol-Villard <[email protected]> > Cc: Tomi Valkeinen <[email protected]> > Cc: [email protected] > Cc: [email protected] > Signed-off-by: Luis R. Rodriguez <[email protected]>
Hey folks, can this be considered to be merged. Thanks, Luis -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
