video: fbdev: sisfb: use arch_phys_wc_add() and ioremap_wc()
This driver uses the same area for MTRR as for the ioremap(). 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() (see commit de33c442 titled "x86 PAT: fix performance drop for glx, use UC minus for ioremap(), ioremap_nocache() and pci_mmap_page_range()") 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: Thomas Winischhofer <thomas@winischhofer.net> Cc: Jean-Christophe Plagniol-Villard <plagnioj@jcrosoft.com> Cc: Tomi Valkeinen <tomi.valkeinen@ti.com> Cc: Suresh Siddha <sbsiddha@gmail.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Juergen Gross <jgross@suse.com> Cc: Daniel Vetter <daniel.vetter@ffwll.ch> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Dave Airlie <airlied@redhat.com> Cc: Antonino Daplas <adaplas@gmail.com> Cc: linux-fbdev@vger.kernel.org Cc: linux-kernel@vger.kernel.org Signed-off-by: Luis R. Rodriguez <mcgrof@suse.com> Reviewed-by: Dave Airlie <airlied@redhat.com> Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
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