Re: [Linux-fbdev-devel] Re: [PATCH] fbdev: Fix IO access in rivafb

[Guido Guenther <agx@sigxcpu.org>]

On Fri, Nov 12, 2004 at 11:32:07AM -0800, Linus Torvalds wrote:
> 
> 
> On Fri, 12 Nov 2004, Guido Guenther wrote:
> >
> > O.k., it was the __raw_{write,read}b which broke things, not the
> > "alignment". This one works:
> 
> All right, that's as expected. However, it does seem to point out that the 
> riva driver depends on _different_ memory ordering guarantees for the 
> 8-bit accesses as opposed to the other ones. Whee. Can you say "UGGLEE"?

Aglie. This scared me too, so I had another look. It seems P{V,C}IO
areas are only accessed using VGA_{RD,WR}8 macros. NV_{RW,WR}08 are
never actually used directly. So this patch makes at least usage
consistent. VGA_{RD,WR}8 to access "I/O areas" in an ordered way. NV_*
for the rest. Please apply.
Cheers,
 -- Guido

--- linux-2.6.10-rc1-mm5/drivers/video/riva/riva_hw.orig.2	2004-11-13 12:24:48.000000000 +0100
+++ linux-2.6.10-rc1-mm5/drivers/video/riva/riva_hw.h	2004-11-13 12:24:56.000000000 +0100
@@ -75,15 +75,15 @@
  */
 #include <asm/io.h>
 
-#define NV_WR08(p,i,d)  (writeb((d), (void __iomem *)(p) + (i)))
-#define NV_RD08(p,i)    (readb((void __iomem *)(p) + (i)))
+#define NV_WR08(p,i,d)  (__raw_writeb((d), (void __iomem *)(p) + (i)))
+#define NV_RD08(p,i)    (__raw_readb((void __iomem *)(p) + (i)))
 #define NV_WR16(p,i,d)  (__raw_writew((d), (void __iomem *)(p) + (i)))
 #define NV_RD16(p,i)    (__raw_readw((void __iomem *)(p) + (i)))
 #define NV_WR32(p,i,d)  (__raw_writel((d), (void __iomem *)(p) + (i)))
 #define NV_RD32(p,i)    (__raw_readl((void __iomem *)(p) + (i)))
 
-#define VGA_WR08(p,i,d) NV_WR08(p,i,d)
-#define VGA_RD08(p,i)   NV_RD08(p,i)
+#define VGA_WR08(p,i,d) (writeb((d), (void __iomem *)(p) + (i)))
+#define VGA_RD08(p,i)   (readb((void __iomem *)(p) + (i)))
 
 /*
  * Define different architectures.

Signed-Off-By: Guido Guenther <agx@sigxcpu.org>