powerpc: Add ioremap_wc

Add ioremap_wc so drivers can request write combining on kernel
mappings.

Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

2 files changed, 19 insertions, 0 deletions

diff --git a/arch/powerpc/mm/pgtable_32.c b/arch/powerpc/mm/pgtable_32.c
index 8dc41c0157fe..fca98f8fb600 100644
--- a/arch/powerpc/mm/pgtable_32.c
+++ b/arch/powerpc/mm/pgtable_32.c
@@ -133,6 +133,14 @@ ioremap(phys_addr_t addr, unsigned long size)
 EXPORT_SYMBOL(ioremap);
 
 void __iomem *
+ioremap_wc(phys_addr_t addr, unsigned long size)
+{
+	return __ioremap_caller(addr, size, _PAGE_NO_CACHE,
+				__builtin_return_address(0));
+}
+EXPORT_SYMBOL(ioremap_wc);
+
+void __iomem *
 ioremap_flags(phys_addr_t addr, unsigned long size, unsigned long flags)
 {
 	/* writeable implies dirty for kernel addresses */
diff --git a/arch/powerpc/mm/pgtable_64.c b/arch/powerpc/mm/pgtable_64.c
index 88927a05cdc2..1146fc6e8921 100644
--- a/arch/powerpc/mm/pgtable_64.c
+++ b/arch/powerpc/mm/pgtable_64.c
@@ -255,6 +255,16 @@ void __iomem * ioremap(phys_addr_t addr, unsigned long size)
 	return __ioremap_caller(addr, size, flags, caller);
 }
 
+void __iomem * ioremap_wc(phys_addr_t addr, unsigned long size)
+{
+	unsigned long flags = _PAGE_NO_CACHE;
+	void *caller = __builtin_return_address(0);
+
+	if (ppc_md.ioremap)
+		return ppc_md.ioremap(addr, size, flags, caller);
+	return __ioremap_caller(addr, size, flags, caller);
+}
+
 void __iomem * ioremap_flags(phys_addr_t addr, unsigned long size,
 			     unsigned long flags)
 {
@@ -311,6 +321,7 @@ void iounmap(volatile void __iomem *token)
 }
 
 EXPORT_SYMBOL(ioremap);
+EXPORT_SYMBOL(ioremap_wc);
 EXPORT_SYMBOL(ioremap_flags);
 EXPORT_SYMBOL(__ioremap);
 EXPORT_SYMBOL(__ioremap_at);