diff options
Diffstat (limited to 'arch/powerpc/include/asm/page.h')
| -rw-r--r-- | arch/powerpc/include/asm/page.h | 154 |
1 files changed, 146 insertions, 8 deletions
diff --git a/arch/powerpc/include/asm/page.h b/arch/powerpc/include/asm/page.h index da4b2000854..32e4e212b9c 100644 --- a/arch/powerpc/include/asm/page.h +++ b/arch/powerpc/include/asm/page.h @@ -36,6 +36,18 @@ #define PAGE_SIZE (ASM_CONST(1) << PAGE_SHIFT) +#ifndef __ASSEMBLY__ +#ifdef CONFIG_HUGETLB_PAGE +extern unsigned int HPAGE_SHIFT; +#else +#define HPAGE_SHIFT PAGE_SHIFT +#endif +#define HPAGE_SIZE ((1UL) << HPAGE_SHIFT) +#define HPAGE_MASK (~(HPAGE_SIZE - 1)) +#define HUGETLB_PAGE_ORDER (HPAGE_SHIFT - PAGE_SHIFT) +#define HUGE_MAX_HSTATE (MMU_PAGE_COUNT-1) +#endif + /* We do define AT_SYSINFO_EHDR but don't use the gate mechanism */ #define __HAVE_ARCH_GATE_AREA 1 @@ -66,7 +78,7 @@ * * Also, KERNELBASE >= PAGE_OFFSET and PHYSICAL_START >= MEMORY_START * - * There are two was to determine a physical address from a virtual one: + * There are two ways to determine a physical address from a virtual one: * va = pa + PAGE_OFFSET - MEMORY_START * va = pa + KERNELBASE - PHYSICAL_START * @@ -80,27 +92,41 @@ #define PAGE_OFFSET ASM_CONST(CONFIG_PAGE_OFFSET) #define LOAD_OFFSET ASM_CONST((CONFIG_KERNEL_START-CONFIG_PHYSICAL_START)) -#if defined(CONFIG_RELOCATABLE) +#if defined(CONFIG_NONSTATIC_KERNEL) #ifndef __ASSEMBLY__ extern phys_addr_t memstart_addr; extern phys_addr_t kernstart_addr; + +#ifdef CONFIG_RELOCATABLE_PPC32 +extern long long virt_phys_offset; #endif + +#endif /* __ASSEMBLY__ */ #define PHYSICAL_START kernstart_addr -#else + +#else /* !CONFIG_NONSTATIC_KERNEL */ #define PHYSICAL_START ASM_CONST(CONFIG_PHYSICAL_START) #endif +/* See Description below for VIRT_PHYS_OFFSET */ +#ifdef CONFIG_RELOCATABLE_PPC32 +#define VIRT_PHYS_OFFSET virt_phys_offset +#else +#define VIRT_PHYS_OFFSET (KERNELBASE - PHYSICAL_START) +#endif + + #ifdef CONFIG_PPC64 #define MEMORY_START 0UL -#elif defined(CONFIG_RELOCATABLE) +#elif defined(CONFIG_NONSTATIC_KERNEL) #define MEMORY_START memstart_addr #else #define MEMORY_START (PHYSICAL_START + PAGE_OFFSET - KERNELBASE) #endif #ifdef CONFIG_FLATMEM -#define ARCH_PFN_OFFSET (MEMORY_START >> PAGE_SHIFT) +#define ARCH_PFN_OFFSET ((unsigned long)(MEMORY_START >> PAGE_SHIFT)) #define pfn_valid(pfn) ((pfn) >= ARCH_PFN_OFFSET && (pfn) < max_mapnr) #endif @@ -113,16 +139,91 @@ extern phys_addr_t kernstart_addr; * determine MEMORY_START until then. However we can determine PHYSICAL_START * from information at hand (program counter, TLB lookup). * + * On BookE with RELOCATABLE (RELOCATABLE_PPC32) + * + * With RELOCATABLE_PPC32, we support loading the kernel at any physical + * address without any restriction on the page alignment. + * + * We find the runtime address of _stext and relocate ourselves based on + * the following calculation: + * + * virtual_base = ALIGN_DOWN(KERNELBASE,256M) + + * MODULO(_stext.run,256M) + * and create the following mapping: + * + * ALIGN_DOWN(_stext.run,256M) => ALIGN_DOWN(KERNELBASE,256M) + * + * When we process relocations, we cannot depend on the + * existing equation for the __va()/__pa() translations: + * + * __va(x) = (x) - PHYSICAL_START + KERNELBASE + * + * Where: + * PHYSICAL_START = kernstart_addr = Physical address of _stext + * KERNELBASE = Compiled virtual address of _stext. + * + * This formula holds true iff, kernel load address is TLB page aligned. + * + * In our case, we need to also account for the shift in the kernel Virtual + * address. + * + * E.g., + * + * Let the kernel be loaded at 64MB and KERNELBASE be 0xc0000000 (same as PAGE_OFFSET). + * In this case, we would be mapping 0 to 0xc0000000, and kernstart_addr = 64M + * + * Now __va(1MB) = (0x100000) - (0x4000000) + 0xc0000000 + * = 0xbc100000 , which is wrong. + * + * Rather, it should be : 0xc0000000 + 0x100000 = 0xc0100000 + * according to our mapping. + * + * Hence we use the following formula to get the translations right: + * + * __va(x) = (x) - [ PHYSICAL_START - Effective KERNELBASE ] + * + * Where : + * PHYSICAL_START = dynamic load address.(kernstart_addr variable) + * Effective KERNELBASE = virtual_base = + * = ALIGN_DOWN(KERNELBASE,256M) + + * MODULO(PHYSICAL_START,256M) + * + * To make the cost of __va() / __pa() more light weight, we introduce + * a new variable virt_phys_offset, which will hold : + * + * virt_phys_offset = Effective KERNELBASE - PHYSICAL_START + * = ALIGN_DOWN(KERNELBASE,256M) - + * ALIGN_DOWN(PHYSICALSTART,256M) + * + * Hence : + * + * __va(x) = x - PHYSICAL_START + Effective KERNELBASE + * = x + virt_phys_offset + * + * and + * __pa(x) = x + PHYSICAL_START - Effective KERNELBASE + * = x - virt_phys_offset + * * On non-Book-E PPC64 PAGE_OFFSET and MEMORY_START are constants so use * the other definitions for __va & __pa. */ #ifdef CONFIG_BOOKE -#define __va(x) ((void *)(unsigned long)((phys_addr_t)(x) - PHYSICAL_START + KERNELBASE)) -#define __pa(x) ((unsigned long)(x) + PHYSICAL_START - KERNELBASE) +#define __va(x) ((void *)(unsigned long)((phys_addr_t)(x) + VIRT_PHYS_OFFSET)) +#define __pa(x) ((unsigned long)(x) - VIRT_PHYS_OFFSET) #else +#ifdef CONFIG_PPC64 +/* + * gcc miscompiles (unsigned long)(&static_var) - PAGE_OFFSET + * with -mcmodel=medium, so we use & and | instead of - and + on 64-bit. + */ +#define __va(x) ((void *)(unsigned long)((phys_addr_t)(x) | PAGE_OFFSET)) +#define __pa(x) ((unsigned long)(x) & 0x0fffffffffffffffUL) + +#else /* 32-bit, non book E */ #define __va(x) ((void *)(unsigned long)((phys_addr_t)(x) + PAGE_OFFSET - MEMORY_START)) #define __pa(x) ((unsigned long)(x) - PAGE_OFFSET + MEMORY_START) #endif +#endif /* * Unfortunately the PLT is in the BSS in the PPC32 ELF ABI, @@ -158,6 +259,26 @@ extern phys_addr_t kernstart_addr; #define is_kernel_addr(x) ((x) >= PAGE_OFFSET) #endif +#ifndef CONFIG_PPC_BOOK3S_64 +/* + * Use the top bit of the higher-level page table entries to indicate whether + * the entries we point to contain hugepages. This works because we know that + * the page tables live in kernel space. If we ever decide to support having + * page tables at arbitrary addresses, this breaks and will have to change. + */ +#ifdef CONFIG_PPC64 +#define PD_HUGE 0x8000000000000000 +#else +#define PD_HUGE 0x80000000 +#endif +#endif /* CONFIG_PPC_BOOK3S_64 */ + +/* + * Some number of bits at the level of the page table that points to + * a hugepte are used to encode the size. This masks those bits. + */ +#define HUGEPD_SHIFT_MASK 0x3f + #ifndef __ASSEMBLY__ #undef STRICT_MM_TYPECHECKS @@ -243,17 +364,29 @@ typedef unsigned long pgprot_t; #endif typedef struct { signed long pd; } hugepd_t; -#define HUGEPD_SHIFT_MASK 0x3f #ifdef CONFIG_HUGETLB_PAGE +#ifdef CONFIG_PPC_BOOK3S_64 +static inline int hugepd_ok(hugepd_t hpd) +{ + /* + * hugepd pointer, bottom two bits == 00 and next 4 bits + * indicate size of table + */ + return (((hpd.pd & 0x3) == 0x0) && ((hpd.pd & HUGEPD_SHIFT_MASK) != 0)); +} +#else static inline int hugepd_ok(hugepd_t hpd) { return (hpd.pd > 0); } +#endif #define is_hugepd(pdep) (hugepd_ok(*((hugepd_t *)(pdep)))) +int pgd_huge(pgd_t pgd); #else /* CONFIG_HUGETLB_PAGE */ #define is_hugepd(pdep) 0 +#define pgd_huge(pgd) 0 #endif /* CONFIG_HUGETLB_PAGE */ struct page; @@ -261,6 +394,7 @@ extern void clear_user_page(void *page, unsigned long vaddr, struct page *pg); extern void copy_user_page(void *to, void *from, unsigned long vaddr, struct page *p); extern int page_is_ram(unsigned long pfn); +extern int devmem_is_allowed(unsigned long pfn); #ifdef CONFIG_PPC_SMLPAR void arch_free_page(struct page *page, int order); @@ -269,7 +403,11 @@ void arch_free_page(struct page *page, int order); struct vm_area_struct; +#if defined(CONFIG_PPC_64K_PAGES) && defined(CONFIG_PPC64) +typedef pte_t *pgtable_t; +#else typedef struct page *pgtable_t; +#endif #include <asm-generic/memory_model.h> #endif /* __ASSEMBLY__ */ |