sh: Fix up legacy PTEA space attribute mapping.

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>
Cc: stable@kernel.org
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This commit is contained in:
Paul Mundt 2011-01-11 15:02:59 +09:00
parent 11e1ed6e88
commit efb3e34b61
2 changed files with 15 additions and 2 deletions

View File

@ -290,7 +290,15 @@ __ioremap_29bit(phys_addr_t offset, unsigned long size, pgprot_t prot)
* 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);

View File

@ -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)
{