diff options
| -rw-r--r-- | arch/xtensa/Kconfig | 18 | ||||
| -rw-r--r-- | arch/xtensa/include/asm/fixmap.h | 58 | ||||
| -rw-r--r-- | arch/xtensa/include/asm/highmem.h | 45 | ||||
| -rw-r--r-- | arch/xtensa/include/asm/pgtable.h | 4 | ||||
| -rw-r--r-- | arch/xtensa/mm/Makefile | 1 | ||||
| -rw-r--r-- | arch/xtensa/mm/cache.c | 7 | ||||
| -rw-r--r-- | arch/xtensa/mm/highmem.c | 72 | ||||
| -rw-r--r-- | arch/xtensa/mm/init.c | 45 | ||||
| -rw-r--r-- | arch/xtensa/mm/mmu.c | 36 |
9 files changed, 270 insertions, 16 deletions
diff --git a/arch/xtensa/Kconfig b/arch/xtensa/Kconfig index df6f86ca6c1a..17b31982c566 100644 --- a/arch/xtensa/Kconfig +++ b/arch/xtensa/Kconfig @@ -190,6 +190,24 @@ config INITIALIZE_XTENSA_MMU_INSIDE_VMLINUX If in doubt, say Y. +config HIGHMEM + bool "High Memory Support" + help + Linux can use the full amount of RAM in the system by + default. However, the default MMUv2 setup only maps the + lowermost 128 MB of memory linearly to the areas starting + at 0xd0000000 (cached) and 0xd8000000 (uncached). + When there are more than 128 MB memory in the system not + all of it can be "permanently mapped" by the kernel. + The physical memory that's not permanently mapped is called + "high memory". + + If you are compiling a kernel which will never run on a + machine with more than 128 MB total physical RAM, answer + N here. + + If unsure, say Y. + endmenu config XTENSA_CALIBRATE_CCOUNT diff --git a/arch/xtensa/include/asm/fixmap.h b/arch/xtensa/include/asm/fixmap.h new file mode 100644 index 000000000000..9f6c33d0428a --- /dev/null +++ b/arch/xtensa/include/asm/fixmap.h @@ -0,0 +1,58 @@ +/* + * fixmap.h: compile-time virtual memory allocation + * + * This file is subject to the terms and conditions of the GNU General Public + * License. See the file "COPYING" in the main directory of this archive + * for more details. + * + * Copyright (C) 1998 Ingo Molnar + * + * Support of BIGMEM added by Gerhard Wichert, Siemens AG, July 1999 + */ + +#ifndef _ASM_FIXMAP_H +#define _ASM_FIXMAP_H + +#include <asm/pgtable.h> +#ifdef CONFIG_HIGHMEM +#include <linux/threads.h> +#include <asm/kmap_types.h> +#endif + +/* + * Here we define all the compile-time 'special' virtual + * addresses. The point is to have a constant address at + * compile time, but to set the physical address only + * in the boot process. We allocate these special addresses + * from the end of the consistent memory region backwards. + * Also this lets us do fail-safe vmalloc(), we + * can guarantee that these special addresses and + * vmalloc()-ed addresses never overlap. + * + * these 'compile-time allocated' memory buffers are + * fixed-size 4k pages. (or larger if used with an increment + * higher than 1) use fixmap_set(idx,phys) to associate + * physical memory with fixmap indices. + */ +enum fixed_addresses { +#ifdef CONFIG_HIGHMEM + /* reserved pte's for temporary kernel mappings */ + FIX_KMAP_BEGIN, + FIX_KMAP_END = FIX_KMAP_BEGIN + (KM_TYPE_NR * NR_CPUS) - 1, +#endif + __end_of_fixed_addresses +}; + +#define FIXADDR_TOP (VMALLOC_START - PAGE_SIZE) +#define FIXADDR_SIZE (__end_of_fixed_addresses << PAGE_SHIFT) +#define FIXADDR_START ((FIXADDR_TOP - FIXADDR_SIZE) & PMD_MASK) + +#include <asm-generic/fixmap.h> + +#define kmap_get_fixmap_pte(vaddr) \ + pte_offset_kernel( \ + pmd_offset(pud_offset(pgd_offset_k(vaddr), (vaddr)), (vaddr)), \ + (vaddr) \ + ) + +#endif diff --git a/arch/xtensa/include/asm/highmem.h b/arch/xtensa/include/asm/highmem.h index 80be15124697..2653ef5d55f1 100644 --- a/arch/xtensa/include/asm/highmem.h +++ b/arch/xtensa/include/asm/highmem.h @@ -6,11 +6,54 @@ * this archive for more details. * * Copyright (C) 2003 - 2005 Tensilica Inc. + * Copyright (C) 2014 Cadence Design Systems Inc. */ #ifndef _XTENSA_HIGHMEM_H #define _XTENSA_HIGHMEM_H -extern void flush_cache_kmaps(void); +#include <asm/cacheflush.h> +#include <asm/fixmap.h> +#include <asm/kmap_types.h> +#include <asm/pgtable.h> + +#define PKMAP_BASE (FIXADDR_START - PMD_SIZE) +#define LAST_PKMAP PTRS_PER_PTE +#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)) + +#define kmap_prot PAGE_KERNEL + +extern pte_t *pkmap_page_table; + +void *kmap_high(struct page *page); +void kunmap_high(struct page *page); + +static inline void *kmap(struct page *page) +{ + BUG_ON(in_interrupt()); + if (!PageHighMem(page)) + return page_address(page); + return kmap_high(page); +} + +static inline void kunmap(struct page *page) +{ + BUG_ON(in_interrupt()); + if (!PageHighMem(page)) + return; + kunmap_high(page); +} + +static inline void flush_cache_kmaps(void) +{ + flush_cache_all(); +} + +void *kmap_atomic(struct page *page); +void __kunmap_atomic(void *kvaddr); + +void kmap_init(void); #endif diff --git a/arch/xtensa/include/asm/pgtable.h b/arch/xtensa/include/asm/pgtable.h index 216446295ada..4b0ca35a93b1 100644 --- a/arch/xtensa/include/asm/pgtable.h +++ b/arch/xtensa/include/asm/pgtable.h @@ -310,6 +310,10 @@ set_pte_at(struct mm_struct *mm, unsigned long addr, pte_t *ptep, pte_t pteval) update_pte(ptep, pteval); } +static inline void set_pte(pte_t *ptep, pte_t pteval) +{ + update_pte(ptep, pteval); +} static inline void set_pmd(pmd_t *pmdp, pmd_t pmdval) diff --git a/arch/xtensa/mm/Makefile b/arch/xtensa/mm/Makefile index f0b646d2f843..f54f78e24d7b 100644 --- a/arch/xtensa/mm/Makefile +++ b/arch/xtensa/mm/Makefile @@ -4,3 +4,4 @@ obj-y := init.o cache.o misc.o obj-$(CONFIG_MMU) += fault.o mmu.o tlb.o +obj-$(CONFIG_HIGHMEM) += highmem.o diff --git a/arch/xtensa/mm/cache.c b/arch/xtensa/mm/cache.c index ba4c47f291b1..63cbb867dadd 100644 --- a/arch/xtensa/mm/cache.c +++ b/arch/xtensa/mm/cache.c @@ -59,6 +59,10 @@ * */ +#if (DCACHE_WAY_SIZE > PAGE_SIZE) && defined(CONFIG_HIGHMEM) +#error "HIGHMEM is not supported on cores with aliasing cache." +#endif + #if (DCACHE_WAY_SIZE > PAGE_SIZE) && XCHAL_DCACHE_IS_WRITEBACK /* @@ -179,10 +183,11 @@ update_mmu_cache(struct vm_area_struct * vma, unsigned long addr, pte_t *ptep) #else if (!PageReserved(page) && !test_bit(PG_arch_1, &page->flags) && (vma->vm_flags & VM_EXEC) != 0) { - unsigned long paddr = (unsigned long) page_address(page); + unsigned long paddr = (unsigned long)kmap_atomic(page); __flush_dcache_page(paddr); __invalidate_icache_page(paddr); set_bit(PG_arch_1, &page->flags); + kunmap_atomic((void *)paddr); } #endif } diff --git a/arch/xtensa/mm/highmem.c b/arch/xtensa/mm/highmem.c new file mode 100644 index 000000000000..17a8c0d6fd17 --- /dev/null +++ b/arch/xtensa/mm/highmem.c @@ -0,0 +1,72 @@ +/* + * High memory support for Xtensa architecture + * + * This file is subject to the terms and conditions of the GNU General + * Public License. See the file "COPYING" in the main directory of + * this archive for more details. + * + * Copyright (C) 2014 Cadence Design Systems Inc. + */ + +#include <linux/export.h> +#include <linux/highmem.h> +#include <asm/tlbflush.h> + +static pte_t *kmap_pte; + +void *kmap_atomic(struct page *page) +{ + enum fixed_addresses idx; + unsigned long vaddr; + int type; + + pagefault_disable(); + if (!PageHighMem(page)) + return page_address(page); + + type = kmap_atomic_idx_push(); + idx = type + KM_TYPE_NR * smp_processor_id(); + vaddr = __fix_to_virt(FIX_KMAP_BEGIN + idx); +#ifdef CONFIG_DEBUG_HIGHMEM + BUG_ON(!pte_none(*(kmap_pte - idx))); +#endif + set_pte(kmap_pte - idx, mk_pte(page, PAGE_KERNEL_EXEC)); + + return (void *)vaddr; +} +EXPORT_SYMBOL(kmap_atomic); + +void __kunmap_atomic(void *kvaddr) +{ + int idx, type; + + if (kvaddr >= (void *)FIXADDR_START && + kvaddr < (void *)FIXADDR_TOP) { + type = kmap_atomic_idx(); + idx = type + KM_TYPE_NR * smp_processor_id(); + + /* + * Force other mappings to Oops if they'll try to access this + * pte without first remap it. Keeping stale mappings around + * is a bad idea also, in case the page changes cacheability + * attributes or becomes a protected page in a hypervisor. + */ + pte_clear(&init_mm, kvaddr, kmap_pte - idx); + local_flush_tlb_kernel_range((unsigned long)kvaddr, + (unsigned long)kvaddr + PAGE_SIZE); + + kmap_atomic_idx_pop(); + } + + pagefault_enable(); +} +EXPORT_SYMBOL(__kunmap_atomic); + +void __init kmap_init(void) +{ + unsigned long kmap_vstart; + + /* cache the first kmap pte */ + kmap_vstart = __fix_to_virt(FIX_KMAP_BEGIN); + kmap_pte = kmap_get_fixmap_pte(kmap_vstart); +} diff --git a/arch/xtensa/mm/init.c b/arch/xtensa/mm/init.c index 03bd025307e3..4224256bb215 100644 --- a/arch/xtensa/mm/init.c +++ b/arch/xtensa/mm/init.c @@ -20,6 +20,7 @@ #include <linux/errno.h> #include <linux/bootmem.h> #include <linux/gfp.h> +#include <linux/highmem.h> #include <linux/swap.h> #include <linux/mman.h> #include <linux/nodemask.h> @@ -296,19 +297,13 @@ void __init bootmem_init(void) void __init zones_init(void) { - unsigned long zones_size[MAX_NR_ZONES]; - int i; - /* All pages are DMA-able, so we put them all in the DMA zone. */ - - zones_size[ZONE_DMA] = max_low_pfn - ARCH_PFN_OFFSET; - for (i = 1; i < MAX_NR_ZONES; i++) - zones_size[i] = 0; - + unsigned long zones_size[MAX_NR_ZONES] = { + [ZONE_DMA] = max_low_pfn - ARCH_PFN_OFFSET, #ifdef CONFIG_HIGHMEM - zones_size[ZONE_HIGHMEM] = max_pfn - max_low_pfn; + [ZONE_HIGHMEM] = max_pfn - max_low_pfn, #endif - + }; free_area_init_node(0, zones_size, ARCH_PFN_OFFSET, NULL); } @@ -318,16 +313,38 @@ void __init zones_init(void) void __init mem_init(void) { - max_mapnr = max_low_pfn - ARCH_PFN_OFFSET; - high_memory = (void *) __va(max_low_pfn << PAGE_SHIFT); - #ifdef CONFIG_HIGHMEM -#error HIGHGMEM not implemented in init.c + unsigned long tmp; + + reset_all_zones_managed_pages(); + for (tmp = max_low_pfn; tmp < max_pfn; tmp++) + free_highmem_page(pfn_to_page(tmp)); #endif + max_mapnr = max_pfn - ARCH_PFN_OFFSET; + high_memory = (void *)__va(max_low_pfn << PAGE_SHIFT); + free_all_bootmem(); mem_init_print_info(NULL); + pr_info("virtual kernel memory layout:\n" +#ifdef CONFIG_HIGHMEM + " pkmap : 0x%08lx - 0x%08lx (%5lu kB)\n" + " fixmap : 0x%08lx - 0x%08lx (%5lu kB)\n" +#endif + " vmalloc : 0x%08x - 0x%08x (%5u MB)\n" + " lowmem : 0x%08x - 0x%08lx (%5lu MB)\n", +#ifdef CONFIG_HIGHMEM + PKMAP_BASE, PKMAP_BASE + LAST_PKMAP * PAGE_SIZE, + (LAST_PKMAP*PAGE_SIZE) >> 10, + FIXADDR_START, FIXADDR_TOP, + (FIXADDR_TOP - FIXADDR_START) >> 10, +#endif + VMALLOC_START, VMALLOC_END, + (VMALLOC_END - VMALLOC_START) >> 20, + PAGE_OFFSET, PAGE_OFFSET + + (max_low_pfn - min_low_pfn) * PAGE_SIZE, + ((max_low_pfn - min_low_pfn) * PAGE_SIZE) >> 20); } #ifdef CONFIG_BLK_DEV_INITRD diff --git a/arch/xtensa/mm/mmu.c b/arch/xtensa/mm/mmu.c index 861203e958da..3429b483d9f8 100644 --- a/arch/xtensa/mm/mmu.c +++ b/arch/xtensa/mm/mmu.c @@ -3,6 +3,7 @@ * * Extracted from init.c */ +#include <linux/bootmem.h> #include <linux/percpu.h> #include <linux/init.h> #include <linux/string.h> @@ -16,9 +17,44 @@ #include <asm/initialize_mmu.h> #include <asm/io.h> +#if defined(CONFIG_HIGHMEM) +static void * __init init_pmd(unsigned long vaddr) +{ + pgd_t *pgd = pgd_offset_k(vaddr); + pmd_t *pmd = pmd_offset(pgd, vaddr); + + if (pmd_none(*pmd)) { + unsigned i; + pte_t *pte = alloc_bootmem_low_pages(PAGE_SIZE); + + for (i = 0; i < 1024; i++) + pte_clear(NULL, 0, pte + i); + + set_pmd(pmd, __pmd(((unsigned long)pte) & PAGE_MASK)); + BUG_ON(pte != pte_offset_kernel(pmd, 0)); + pr_debug("%s: vaddr: 0x%08lx, pmd: 0x%p, pte: 0x%p\n", + __func__, vaddr, pmd, pte); + return pte; + } else { + return pte_offset_kernel(pmd, 0); + } +} + +static void __init fixedrange_init(void) +{ + BUILD_BUG_ON(FIXADDR_SIZE > PMD_SIZE); + init_pmd(__fix_to_virt(__end_of_fixed_addresses - 1) & PMD_MASK); +} +#endif + void __init paging_init(void) { memset(swapper_pg_dir, 0, PAGE_SIZE); +#ifdef CONFIG_HIGHMEM + fixedrange_init(); + pkmap_page_table = init_pmd(PKMAP_BASE); + kmap_init(); +#endif } /* |