sh: Preliminary support for SH-X2 MMU.

This adds some preliminary support for the SH-X2 MMU, used by
newer SH-4A parts (particularly SH7785).

This MMU implements a 'compat' mode with SH-X MMUs and an
'extended' mode for SH-X2 extended features. Extended features
include additional page sizes (8kB, 4MB, 64MB), as well as the
addition of page execute permissions.

The extended mode attributes are placed in a second data array,
which requires us to switch to 64-bit PTEs when in X2 mode.

With the addition of the exec perms, we also overhaul the mmap
prots somewhat, now that it's possible to handle them more
intelligently.

Signed-off-by: Paul Mundt <lethal@linux-sh.org>

1 files changed, 2 insertions, 10 deletions

diff --git a/arch/sh/mm/pg-sh4.c b/arch/sh/mm/pg-sh4.c
index 07371ed7a313..e973ac3b13be 100644
--- a/arch/sh/mm/pg-sh4.c
+++ b/arch/sh/mm/pg-sh4.c
@@ -37,10 +37,6 @@ void clear_user_page(void *to, unsigned long address, struct page *page)
         if (((address ^ (unsigned long)to) & CACHE_ALIAS) == 0)
                 clear_page(to);
         else {
-                pgprot_t pgprot = __pgprot(_PAGE_PRESENT |
-                                           _PAGE_RW | _PAGE_CACHABLE |
-                                           _PAGE_DIRTY | _PAGE_ACCESSED |
-                                           _PAGE_HW_SHARED | _PAGE_FLAGS_HARD);
                 unsigned long phys_addr = PHYSADDR(to);
                 unsigned long p3_addr = P3SEG + (address & CACHE_ALIAS);
                 pgd_t *pgd = pgd_offset_k(p3_addr);
@@ -50,7 +46,7 @@ void clear_user_page(void *to, unsigned long address, struct page *page)
                 pte_t entry;
                 unsigned long flags;
 
-                entry = pfn_pte(phys_addr >> PAGE_SHIFT, pgprot);
+                entry = pfn_pte(phys_addr >> PAGE_SHIFT, PAGE_KERNEL);
                 down(&p3map_sem[(address & CACHE_ALIAS)>>12]);
                 set_pte(pte, entry);
                 local_irq_save(flags);
@@ -77,10 +73,6 @@ void copy_user_page(void *to, void *from, unsigned long address,
         if (((address ^ (unsigned long)to) & CACHE_ALIAS) == 0)
                 copy_page(to, from);
         else {
-                pgprot_t pgprot = __pgprot(_PAGE_PRESENT |
-                                           _PAGE_RW | _PAGE_CACHABLE |
-                                           _PAGE_DIRTY | _PAGE_ACCESSED |
-                                           _PAGE_HW_SHARED | _PAGE_FLAGS_HARD);
                 unsigned long phys_addr = PHYSADDR(to);
                 unsigned long p3_addr = P3SEG + (address & CACHE_ALIAS);
                 pgd_t *pgd = pgd_offset_k(p3_addr);
@@ -90,7 +82,7 @@ void copy_user_page(void *to, void *from, unsigned long address,
                 pte_t entry;
                 unsigned long flags;
 
-                entry = pfn_pte(phys_addr >> PAGE_SHIFT, pgprot);
+                entry = pfn_pte(phys_addr >> PAGE_SHIFT, PAGE_KERNEL);
                 down(&p3map_sem[(address & CACHE_ALIAS)>>12]);
                 set_pte(pte, entry);
                 local_irq_save(flags);