powerpc/44x: Support 16K/64K base page sizes on 44x
This adds support for 16k and 64k page sizes on PowerPC 44x processors.
The PGDIR table is much smaller than a page when using 16k or 64k
pages (512 and 32 bytes respectively) so we allocate the PGDIR with
kzalloc() instead of __get_free_pages().
One PTE table covers rather a large memory area when using 16k or 64k
pages (32MB or 512MB respectively), so we can easily put FIXMAP and
PKMAP in the area covered by one PTE table.
Signed-off-by: Yuri Tikhonov <yur@emcraft.com>
Signed-off-by: Vladimir Panfilov <pvr@emcraft.com>
Signed-off-by: Ilya Yanok <yanok@emcraft.com>
Acked-by: Josh Boyer <jwboyer@linux.vnet.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
diff --git a/arch/powerpc/include/asm/page_32.h b/arch/powerpc/include/asm/page_32.h
index d77072a..1458d95 100644
--- a/arch/powerpc/include/asm/page_32.h
+++ b/arch/powerpc/include/asm/page_32.h
@@ -19,6 +19,8 @@
#define PTE_FLAGS_OFFSET 0
#endif
+#define PTE_SHIFT (PAGE_SHIFT - PTE_T_LOG2) /* full page */
+
#ifndef __ASSEMBLY__
/*
* The basic type of a PTE - 64 bits for those CPUs with > 32 bit
@@ -26,10 +28,8 @@
*/
#ifdef CONFIG_PTE_64BIT
typedef unsigned long long pte_basic_t;
-#define PTE_SHIFT (PAGE_SHIFT - 3) /* 512 ptes per page */
#else
typedef unsigned long pte_basic_t;
-#define PTE_SHIFT (PAGE_SHIFT - 2) /* 1024 ptes per page */
#endif
struct page;
@@ -39,6 +39,9 @@
#include <asm-generic/page.h>
+#define PGD_T_LOG2 (__builtin_ffs(sizeof(pgd_t)) - 1)
+#define PTE_T_LOG2 (__builtin_ffs(sizeof(pte_t)) - 1)
+
#endif /* __ASSEMBLY__ */
#endif /* _ASM_POWERPC_PAGE_32_H */