[143/272] sh: Fix up legacy PTEA space attribute mapping.

Greg KH
2011-02-16T01:27:29Z

From: Paul Mundt <lethal@linux-sh.org>

commit efb3e34b6176d30c4fe8635fa8e1beb6280cc2cd upstream.

When p3_ioremap() was converted to ioremap_prot() there was some breakage
introduced where the 29-bit segmentation logic would trap the area range
and return an identity mapping without having allowed the area
specification to force mapping through page tables. This wires up a PCC
mask for pgprot verification to work out whether to short-circuit the
identity mapping on legacy parts, restoring the previous behaviour.

Reported-by: Nobuhiro Iwamatsu <iwamatsu@nigauri.org>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

---
arch/sh/include/asm/io.h | 10 +++++++++-
arch/sh/include/asm/pgtable_32.h | 7 ++++++-
2 files changed, 15 insertions(+), 2 deletions(-)

--- a/arch/sh/include/asm/io.h
+++ b/arch/sh/include/asm/io.h
@@ -322,7 +322,15 @@ __ioremap_29bit(phys_addr_t offset, unsi
* mapping must be done by the PMB or by using page tables.
*/
if (likely(PXSEG(offset) < P3SEG && PXSEG(last_addr) < P3SEG)) {
- if (unlikely(pgprot_val(prot) & _PAGE_CACHABLE))
+ u64 flags = pgprot_val(prot);
+
+ /*
+ * Anything using the legacy PTEA space attributes needs
+ * to be kicked down to page table mappings.
+ */
+ if (unlikely(flags & _PAGE_PCC_MASK))
+ return NULL;
+ if (unlikely(flags & _PAGE_CACHABLE))
return (void __iomem *)P1SEGADDR(offset);

return (void __iomem *)P2SEGADDR(offset);
--- a/arch/sh/include/asm/pgtable_32.h
+++ b/arch/sh/include/asm/pgtable_32.h
@@ -76,6 +76,10 @@
/* Wrapper for extended mode pgprot twiddling */
#define _PAGE_EXT(x) ((unsigned long long)(x) << 32)

+#ifdef CONFIG_X2TLB
+#define _PAGE_PCC_MASK 0x00000000 /* No legacy PTEA support */
+#else
+
/* software: moves to PTEA.TC (Timing Control) */
#define _PAGE_PCC_AREA5 0x00000000 /* use BSC registers for area5 */
#define _PAGE_PCC_AREA6 0x80000000 /* use BSC registers for area6 */
@@ -89,7 +93,8 @@
#define _PAGE_PCC_ATR8 0x60000000 /* Attribute Memory space, 8 bit bus */
#define _PAGE_PCC_ATR16 0x60000001 /* Attribute Memory space, 6 bit bus */

-#ifndef CONFIG_X2TLB
+#define _PAGE_PCC_MASK 0xe0000001
+
/* copy the ptea attributes */
static inline unsigned long copy_ptea_attributes(unsigned long x)
{