[PARISC] Further work for multiple page sizes
More work towards supporing multiple page sizes on 64-bit. Convert
some assumptions that 64bit uses 3 level page tables into testing
PT_NLEVELS. Also some BUG() to BUG_ON() conversions and some cleanups
to assembler.
Signed-off-by: Helge Deller <deller@parisc-linux.org>
Signed-off-by: Kyle McMartin <kyle@parisc-linux.org>
diff --git a/include/asm-parisc/page.h b/include/asm-parisc/page.h
index 45e02aa..c0dd461 100644
--- a/include/asm-parisc/page.h
+++ b/include/asm-parisc/page.h
@@ -1,13 +1,30 @@
#ifndef _PARISC_PAGE_H
#define _PARISC_PAGE_H
-/* PAGE_SHIFT determines the page size */
-#define PAGE_SHIFT 12
-#define PAGE_SIZE (1UL << PAGE_SHIFT)
-#define PAGE_MASK (~(PAGE_SIZE-1))
+#if !defined(__KERNEL__)
+/* this is for userspace applications (4k page size) */
+# define PAGE_SHIFT 12 /* 4k */
+# define PAGE_SIZE (1UL << PAGE_SHIFT)
+# define PAGE_MASK (~(PAGE_SIZE-1))
+#endif
+
#ifdef __KERNEL__
#include <linux/config.h>
+
+#if defined(CONFIG_PARISC_PAGE_SIZE_4KB)
+# define PAGE_SHIFT 12 /* 4k */
+#elif defined(CONFIG_PARISC_PAGE_SIZE_16KB)
+# define PAGE_SHIFT 14 /* 16k */
+#elif defined(CONFIG_PARISC_PAGE_SIZE_64KB)
+# define PAGE_SHIFT 16 /* 64k */
+#else
+# error "unknown default kernel page size"
+#endif
+#define PAGE_SIZE (1UL << PAGE_SHIFT)
+#define PAGE_MASK (~(PAGE_SIZE-1))
+
+
#ifndef __ASSEMBLY__
#include <asm/types.h>
diff --git a/include/asm-parisc/pgtable.h b/include/asm-parisc/pgtable.h
index 4e34c6b..aec089e 100644
--- a/include/asm-parisc/pgtable.h
+++ b/include/asm-parisc/pgtable.h
@@ -59,16 +59,15 @@
#define ISTACK_SIZE 32768 /* Interrupt Stack Size */
#define ISTACK_ORDER 3
-/* This is the size of the initially mapped kernel memory (i.e. currently
- * 0 to 1<<23 == 8MB */
+/* This is the size of the initially mapped kernel memory */
#ifdef CONFIG_64BIT
-#define KERNEL_INITIAL_ORDER 24
+#define KERNEL_INITIAL_ORDER 24 /* 0 to 1<<24 = 16MB */
#else
-#define KERNEL_INITIAL_ORDER 23
+#define KERNEL_INITIAL_ORDER 23 /* 0 to 1<<23 = 8MB */
#endif
#define KERNEL_INITIAL_SIZE (1 << KERNEL_INITIAL_ORDER)
-#ifdef CONFIG_64BIT
+#if defined(CONFIG_64BIT) && defined(CONFIG_PARISC_PAGE_SIZE_4KB)
#define PT_NLEVELS 3
#define PGD_ORDER 1 /* Number of pages per pgd */
#define PMD_ORDER 1 /* Number of pages per pmd */
@@ -111,11 +110,15 @@
#define MAX_ADDRBITS (PGDIR_SHIFT + BITS_PER_PGD)
#define MAX_ADDRESS (1UL << MAX_ADDRBITS)
-#define SPACEID_SHIFT (MAX_ADDRBITS - 32)
+#define SPACEID_SHIFT (MAX_ADDRBITS - 32)
/* This calculates the number of initial pages we need for the initial
* page tables */
-#define PT_INITIAL (1 << (KERNEL_INITIAL_ORDER - PMD_SHIFT))
+#if (KERNEL_INITIAL_ORDER) >= (PMD_SHIFT)
+# define PT_INITIAL (1 << (KERNEL_INITIAL_ORDER - PMD_SHIFT))
+#else
+# define PT_INITIAL (1) /* all initial PTEs fit into one page */
+#endif
/*
* pgd entries used up by user/kernel:
@@ -160,6 +163,10 @@
* to zero */
#define PTE_SHIFT xlate_pabit(_PAGE_USER_BIT)
+/* PFN_PTE_SHIFT defines the shift of a PTE value to access the PFN field */
+#define PFN_PTE_SHIFT 12
+
+
/* this is how many bits may be used by the file functions */
#define PTE_FILE_MAX_BITS (BITS_PER_LONG - PTE_SHIFT)
@@ -188,7 +195,8 @@
/* The pgd/pmd contains a ptr (in phys addr space); since all pgds/pmds
* are page-aligned, we don't care about the PAGE_OFFSET bits, except
* for a few meta-information bits, so we shift the address to be
- * able to effectively address 40-bits of physical address space. */
+ * able to effectively address 40/42/44-bits of physical address space
+ * depending on 4k/16k/64k PAGE_SIZE */
#define _PxD_PRESENT_BIT 31
#define _PxD_ATTACHED_BIT 30
#define _PxD_VALID_BIT 29
@@ -198,7 +206,7 @@
#define PxD_FLAG_VALID (1 << xlate_pabit(_PxD_VALID_BIT))
#define PxD_FLAG_MASK (0xf)
#define PxD_FLAG_SHIFT (4)
-#define PxD_VALUE_SHIFT (8)
+#define PxD_VALUE_SHIFT (8) /* (PAGE_SHIFT-PxD_FLAG_SHIFT) */
#ifndef __ASSEMBLY__
@@ -246,6 +254,7 @@
#define __S110 PAGE_RWX
#define __S111 PAGE_RWX
+
extern pgd_t swapper_pg_dir[]; /* declared in init_task.c */
/* initial page tables for 0-8MB for kernel */
@@ -272,7 +281,7 @@
#define pgd_flag(x) (pgd_val(x) & PxD_FLAG_MASK)
#define pgd_address(x) ((unsigned long)(pgd_val(x) &~ PxD_FLAG_MASK) << PxD_VALUE_SHIFT)
-#ifdef CONFIG_64BIT
+#if PT_NLEVELS == 3
/* The first entry of the permanent pmd is not there if it contains
* the gateway marker */
#define pmd_none(x) (!pmd_val(x) || pmd_flag(x) == PxD_FLAG_ATTACHED)
@@ -282,7 +291,7 @@
#define pmd_bad(x) (!(pmd_flag(x) & PxD_FLAG_VALID))
#define pmd_present(x) (pmd_flag(x) & PxD_FLAG_PRESENT)
static inline void pmd_clear(pmd_t *pmd) {
-#ifdef CONFIG_64BIT
+#if PT_NLEVELS == 3
if (pmd_flag(*pmd) & PxD_FLAG_ATTACHED)
/* This is the entry pointing to the permanent pmd
* attached to the pgd; cannot clear it */
@@ -303,7 +312,7 @@
#define pgd_bad(x) (!(pgd_flag(x) & PxD_FLAG_VALID))
#define pgd_present(x) (pgd_flag(x) & PxD_FLAG_PRESENT)
static inline void pgd_clear(pgd_t *pgd) {
-#ifdef CONFIG_64BIT
+#if PT_NLEVELS == 3
if(pgd_flag(*pgd) & PxD_FLAG_ATTACHED)
/* This is the permanent pmd attached to the pgd; cannot
* free it */
@@ -351,7 +360,7 @@
({ \
pte_t __pte; \
\
- pte_val(__pte) = ((addr)+pgprot_val(pgprot)); \
+ pte_val(__pte) = ((((addr)>>PAGE_SHIFT)<<PFN_PTE_SHIFT) + pgprot_val(pgprot)); \
\
__pte; \
})
@@ -361,20 +370,16 @@
static inline pte_t pfn_pte(unsigned long pfn, pgprot_t pgprot)
{
pte_t pte;
- pte_val(pte) = (pfn << PAGE_SHIFT) | pgprot_val(pgprot);
+ pte_val(pte) = (pfn << PFN_PTE_SHIFT) | pgprot_val(pgprot);
return pte;
}
-/* This takes a physical page address that is used by the remapping functions */
-#define mk_pte_phys(physpage, pgprot) \
-({ pte_t __pte; pte_val(__pte) = physpage + pgprot_val(pgprot); __pte; })
-
extern inline pte_t pte_modify(pte_t pte, pgprot_t newprot)
{ pte_val(pte) = (pte_val(pte) & _PAGE_CHG_MASK) | pgprot_val(newprot); return pte; }
/* Permanent address of a page. On parisc we don't have highmem. */
-#define pte_pfn(x) (pte_val(x) >> PAGE_SHIFT)
+#define pte_pfn(x) (pte_val(x) >> PFN_PTE_SHIFT)
#define pte_page(pte) (pfn_to_page(pte_pfn(pte)))
@@ -499,6 +504,26 @@
#endif /* !__ASSEMBLY__ */
+
+/* TLB page size encoding - see table 3-1 in parisc20.pdf */
+#define _PAGE_SIZE_ENCODING_4K 0
+#define _PAGE_SIZE_ENCODING_16K 1
+#define _PAGE_SIZE_ENCODING_64K 2
+#define _PAGE_SIZE_ENCODING_256K 3
+#define _PAGE_SIZE_ENCODING_1M 4
+#define _PAGE_SIZE_ENCODING_4M 5
+#define _PAGE_SIZE_ENCODING_16M 6
+#define _PAGE_SIZE_ENCODING_64M 7
+
+#if defined(CONFIG_PARISC_PAGE_SIZE_4KB)
+# define _PAGE_SIZE_ENCODING_DEFAULT _PAGE_SIZE_ENCODING_4K
+#elif defined(CONFIG_PARISC_PAGE_SIZE_16KB)
+# define _PAGE_SIZE_ENCODING_DEFAULT _PAGE_SIZE_ENCODING_16K
+#elif defined(CONFIG_PARISC_PAGE_SIZE_64KB)
+# define _PAGE_SIZE_ENCODING_DEFAULT _PAGE_SIZE_ENCODING_64K
+#endif
+
+
#define io_remap_pfn_range(vma, vaddr, pfn, size, prot) \
remap_pfn_range(vma, vaddr, pfn, size, prot)