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/highmem.h b/arch/powerpc/include/asm/highmem.h
index fd97e50..04e4a62 100644
--- a/arch/powerpc/include/asm/highmem.h
+++ b/arch/powerpc/include/asm/highmem.h
@@ -38,9 +38,24 @@
* easily, subsequent pte tables have to be allocated in one physical
* chunk of RAM.
*/
-#define LAST_PKMAP (1 << PTE_SHIFT)
-#define LAST_PKMAP_MASK (LAST_PKMAP-1)
+/*
+ * We use one full pte table with 4K pages. And with 16K/64K pages pte
+ * table covers enough memory (32MB and 512MB resp.) that both FIXMAP
+ * and PKMAP can be placed in single pte table. We use 1024 pages for
+ * PKMAP in case of 16K/64K pages.
+ */
+#ifdef CONFIG_PPC_4K_PAGES
+#define PKMAP_ORDER PTE_SHIFT
+#else
+#define PKMAP_ORDER 10
+#endif
+#define LAST_PKMAP (1 << PKMAP_ORDER)
+#ifndef CONFIG_PPC_4K_PAGES
+#define PKMAP_BASE (FIXADDR_START - PAGE_SIZE*(LAST_PKMAP + 1))
+#else
#define PKMAP_BASE ((FIXADDR_START - PAGE_SIZE*(LAST_PKMAP + 1)) & PMD_MASK)
+#endif
+#define LAST_PKMAP_MASK (LAST_PKMAP-1)
#define PKMAP_NR(virt) ((virt-PKMAP_BASE) >> PAGE_SHIFT)
#define PKMAP_ADDR(nr) (PKMAP_BASE + ((nr) << PAGE_SHIFT))
diff --git a/arch/powerpc/include/asm/mmu-44x.h b/arch/powerpc/include/asm/mmu-44x.h
index b21af32..8a97cfb 100644
--- a/arch/powerpc/include/asm/mmu-44x.h
+++ b/arch/powerpc/include/asm/mmu-44x.h
@@ -4,6 +4,8 @@
* PPC440 support
*/
+#include <asm/page.h>
+
#define PPC44x_MMUCR_TID 0x000000ff
#define PPC44x_MMUCR_STS 0x00010000
@@ -74,4 +76,19 @@
/* Size of the TLBs used for pinning in lowmem */
#define PPC_PIN_SIZE (1 << 28) /* 256M */
+#if (PAGE_SHIFT == 12)
+#define PPC44x_TLBE_SIZE PPC44x_TLB_4K
+#elif (PAGE_SHIFT == 14)
+#define PPC44x_TLBE_SIZE PPC44x_TLB_16K
+#elif (PAGE_SHIFT == 16)
+#define PPC44x_TLBE_SIZE PPC44x_TLB_64K
+#else
+#error "Unsupported PAGE_SIZE"
+#endif
+
+#define PPC44x_PGD_OFF_SHIFT (32 - PGDIR_SHIFT + PGD_T_LOG2)
+#define PPC44x_PGD_OFF_MASK_BIT (PGDIR_SHIFT - PGD_T_LOG2)
+#define PPC44x_PTE_ADD_SHIFT (32 - PGDIR_SHIFT + PTE_SHIFT + PTE_T_LOG2)
+#define PPC44x_PTE_ADD_MASK_BIT (32 - PTE_T_LOG2 - PTE_SHIFT)
+
#endif /* _ASM_POWERPC_MMU_44X_H_ */
diff --git a/arch/powerpc/include/asm/page.h b/arch/powerpc/include/asm/page.h
index c0b8d4a..197d569 100644
--- a/arch/powerpc/include/asm/page.h
+++ b/arch/powerpc/include/asm/page.h
@@ -19,12 +19,15 @@
#include <asm/kdump.h>
/*
- * On PPC32 page size is 4K. For PPC64 we support either 4K or 64K software
+ * On regular PPC32 page size is 4K (but we support 4K/16K/64K pages
+ * on PPC44x). For PPC64 we support either 4K or 64K software
* page size. When using 64K pages however, whether we are really supporting
* 64K pages in HW or not is irrelevant to those definitions.
*/
-#ifdef CONFIG_PPC_64K_PAGES
+#if defined(CONFIG_PPC_64K_PAGES)
#define PAGE_SHIFT 16
+#elif defined(CONFIG_PPC_16K_PAGES)
+#define PAGE_SHIFT 14
#else
#define PAGE_SHIFT 12
#endif
@@ -151,7 +154,7 @@
/* 64k pages additionally define a bigger "real PTE" type that gathers
* the "second half" part of the PTE for pseudo 64k pages
*/
-#ifdef CONFIG_PPC_64K_PAGES
+#if defined(CONFIG_PPC_64K_PAGES) && defined(CONFIG_PPC_STD_MMU_64)
typedef struct { pte_t pte; unsigned long hidx; } real_pte_t;
#else
typedef struct { pte_t pte; } real_pte_t;
@@ -191,10 +194,10 @@
#define pte_val(x) (x)
#define __pte(x) (x)
-#ifdef CONFIG_PPC_64K_PAGES
+#if defined(CONFIG_PPC_64K_PAGES) && defined(CONFIG_PPC_STD_MMU_64)
typedef struct { pte_t pte; unsigned long hidx; } real_pte_t;
#else
-typedef unsigned long real_pte_t;
+typedef pte_t real_pte_t;
#endif
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 */