[PATCH 1/3] powerpc/32: Add ioremap_wt()

[PATCH 1/3] powerpc/32: Add ioremap_wt()

[Christophe Leroy]

Other arches have ioremap_wt() to map IO areas write-through.
Implement it on PPC as well in order to avoid drivers using
__ioremap(_PAGE_WRITETHRU)

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
---
 arch/powerpc/include/asm/io.h | 6 ++++++
 arch/powerpc/mm/pgtable_32.c  | 8 ++++++++
 2 files changed, 14 insertions(+)

diff --git a/arch/powerpc/include/asm/io.h b/arch/powerpc/include/asm/io.h
index e0331e754568..3380b5b22450 100644
--- a/arch/powerpc/include/asm/io.h
+++ b/arch/powerpc/include/asm/io.h
@@ -3,6 +3,9 @@
 #ifdef __KERNEL__
 
 #define ARCH_HAS_IOREMAP_WC
+#ifdef CONFIG_PPC32
+#define ARCH_HAS_IOREMAP_WT
+#endif
 
 /*
  * This program is free software; you can redistribute it and/or
@@ -746,6 +749,8 @@ static inline void iosync(void)
  *
  * * ioremap_wc enables write combining
  *
+ * * ioremap_wt enables write through
+ *
  * * iounmap undoes such a mapping and can be hooked
  *
  * * __ioremap_at (and the pending __iounmap_at) are low level functions to
@@ -767,6 +772,7 @@ extern void __iomem *ioremap(phys_addr_t address, unsigned long size);
 extern void __iomem *ioremap_prot(phys_addr_t address, unsigned long size,
 				  unsigned long flags);
 extern void __iomem *ioremap_wc(phys_addr_t address, unsigned long size);
+void __iomem *ioremap_wt(phys_addr_t address, unsigned long size);
 #define ioremap_nocache(addr, size)	ioremap((addr), (size))
 #define ioremap_uc(addr, size)		ioremap((addr), (size))
 #define ioremap_cache(addr, size) \
diff --git a/arch/powerpc/mm/pgtable_32.c b/arch/powerpc/mm/pgtable_32.c
index 2bbc22384f78..b2e73e82f8fc 100644
--- a/arch/powerpc/mm/pgtable_32.c
+++ b/arch/powerpc/mm/pgtable_32.c
@@ -90,6 +90,14 @@ ioremap_wc(phys_addr_t addr, unsigned long size)
 EXPORT_SYMBOL(ioremap_wc);
 
 void __iomem *
+ioremap_wt(phys_addr_t addr, unsigned long size)
+{
+	return __ioremap_caller(addr, size, _PAGE_WRITETHRU,
+				__builtin_return_address(0));
+}
+EXPORT_SYMBOL(ioremap_wt);
+
+void __iomem *
 ioremap_prot(phys_addr_t addr, unsigned long size, unsigned long flags)
 {
 	pte_t pte = __pte(flags);
-- 
2.13.3

[PATCH 2/3] drivers/video/fbdev: use ioremap_wt() instead of __ioremap(_PAGE_WRITETHRU)

[Christophe Leroy]

_PAGE_WRITETHRU is a target specific flag. Prefer generic functions.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
---
 drivers/video/fbdev/controlfb.c  |  3 +--
 drivers/video/fbdev/platinumfb.c |  3 +--
 drivers/video/fbdev/valkyriefb.c | 10 ++++++----
 3 files changed, 8 insertions(+), 8 deletions(-)

diff --git a/drivers/video/fbdev/controlfb.c b/drivers/video/fbdev/controlfb.c
index 8d14b29aafea..058093990218 100644
--- a/drivers/video/fbdev/controlfb.c
+++ b/drivers/video/fbdev/controlfb.c
@@ -715,8 +715,7 @@ static int __init control_of_init(struct device_node *dp)
 		goto error_out;
 	}
 	/* map at most 8MB for the frame buffer */
-	p->frame_buffer = __ioremap(p->frame_buffer_phys, 0x800000,
-				    _PAGE_WRITETHRU);
+	p->frame_buffer = ioremap_wt(p->frame_buffer_phys, 0x800000);
 
 	if (!p->control_regs_phys ||
 	    !request_mem_region(p->control_regs_phys, p->control_regs_size,
diff --git a/drivers/video/fbdev/platinumfb.c b/drivers/video/fbdev/platinumfb.c
index 377d3399a3ad..df79f102fbc6 100644
--- a/drivers/video/fbdev/platinumfb.c
+++ b/drivers/video/fbdev/platinumfb.c
@@ -577,8 +577,7 @@ static int platinumfb_probe(struct platform_device* odev)
 
 	/* frame buffer - map only 4MB */
 	pinfo->frame_buffer_phys = pinfo->rsrc_fb.start;
-	pinfo->frame_buffer = __ioremap(pinfo->rsrc_fb.start, 0x400000,
-					_PAGE_WRITETHRU);
+	pinfo->frame_buffer = ioremap_wt(pinfo->rsrc_fb.start, 0x400000);
 	pinfo->base_frame_buffer = pinfo->frame_buffer;
 
 	/* registers */
diff --git a/drivers/video/fbdev/valkyriefb.c b/drivers/video/fbdev/valkyriefb.c
index 275fb98236d3..0c6c1eede800 100644
--- a/drivers/video/fbdev/valkyriefb.c
+++ b/drivers/video/fbdev/valkyriefb.c
@@ -318,7 +318,7 @@ static void __init valkyrie_choose_mode(struct fb_info_valkyrie *p)
 int __init valkyriefb_init(void)
 {
 	struct fb_info_valkyrie	*p;
-	unsigned long frame_buffer_phys, cmap_regs_phys, flags;
+	unsigned long frame_buffer_phys, cmap_regs_phys;
 	int err;
 	char *option = NULL;
 
@@ -337,7 +337,6 @@ int __init valkyriefb_init(void)
 	/* Hardcoded addresses... welcome to 68k Macintosh country :-) */
 	frame_buffer_phys = 0xf9000000;
 	cmap_regs_phys = 0x50f24000;
-	flags = IOMAP_NOCACHE_SER; /* IOMAP_WRITETHROUGH?? */
 #else /* ppc (!CONFIG_MAC) */
 	{
 		struct device_node *dp;
@@ -354,7 +353,6 @@ int __init valkyriefb_init(void)
 
 		frame_buffer_phys = r.start;
 		cmap_regs_phys = r.start + 0x304000;
-		flags = _PAGE_WRITETHRU;
 	}
 #endif /* ppc (!CONFIG_MAC) */
 
@@ -369,7 +367,11 @@ int __init valkyriefb_init(void)
 	}
 	p->total_vram = 0x100000;
 	p->frame_buffer_phys = frame_buffer_phys;
-	p->frame_buffer = __ioremap(frame_buffer_phys, p->total_vram, flags);
+#ifdef CONFIG_MAC
+	p->frame_buffer = ioremap_nocache(frame_buffer_phys, p->total_vram);
+#else
+	p->frame_buffer = ioremap_wt(frame_buffer_phys, p->total_vram);
+#endif
 	p->cmap_regs_phys = cmap_regs_phys;
 	p->cmap_regs = ioremap(p->cmap_regs_phys, 0x1000);
 	p->valkyrie_regs_phys = cmap_regs_phys+0x6000;
-- 
2.13.3

[PATCH 3/3] drivers/block/z2ram: use ioremap_wt() instead of __ioremap(_PAGE_WRITETHRU)

[Christophe Leroy]

_PAGE_WRITETHRU is a target specific flag. Prefer generic functions.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
---
 drivers/block/z2ram.c | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/drivers/block/z2ram.c b/drivers/block/z2ram.c
index d0c5bc4e0703..cfbd70520eeb 100644
--- a/drivers/block/z2ram.c
+++ b/drivers/block/z2ram.c
@@ -190,8 +190,7 @@ static int z2_open(struct block_device *bdev, fmode_t mode)
 			vfree(vmalloc (size));
 		}
 
-		vaddr = (unsigned long) __ioremap (paddr, size, 
-						   _PAGE_WRITETHRU);
+		vaddr = (unsigned long)ioremap_wt(paddr, size);
 
 #else
 		vaddr = (unsigned long)z_remap_nocache_nonser(paddr, size);
-- 
2.13.3