diff options
Diffstat (limited to 'arch/ppc/kernel/dma-mapping.c')
-rw-r--r-- | arch/ppc/kernel/dma-mapping.c | 442 |
1 files changed, 0 insertions, 442 deletions
diff --git a/arch/ppc/kernel/dma-mapping.c b/arch/ppc/kernel/dma-mapping.c deleted file mode 100644 index 10fec736396..00000000000 --- a/arch/ppc/kernel/dma-mapping.c +++ /dev/null @@ -1,442 +0,0 @@ -/* - * PowerPC version derived from arch/arm/mm/consistent.c - * Copyright (C) 2001 Dan Malek (dmalek@jlc.net) - * - * Copyright (C) 2000 Russell King - * - * Consistent memory allocators. Used for DMA devices that want to - * share uncached memory with the processor core. The function return - * is the virtual address and 'dma_handle' is the physical address. - * Mostly stolen from the ARM port, with some changes for PowerPC. - * -- Dan - * - * Reorganized to get rid of the arch-specific consistent_* functions - * and provide non-coherent implementations for the DMA API. -Matt - * - * Added in_interrupt() safe dma_alloc_coherent()/dma_free_coherent() - * implementation. This is pulled straight from ARM and barely - * modified. -Matt - * - * This program is free software; you can redistribute it and/or modify - * it under the terms of the GNU General Public License version 2 as - * published by the Free Software Foundation. - */ - -#include <linux/module.h> -#include <linux/signal.h> -#include <linux/sched.h> -#include <linux/kernel.h> -#include <linux/errno.h> -#include <linux/string.h> -#include <linux/types.h> -#include <linux/ptrace.h> -#include <linux/mman.h> -#include <linux/mm.h> -#include <linux/swap.h> -#include <linux/stddef.h> -#include <linux/vmalloc.h> -#include <linux/init.h> -#include <linux/delay.h> -#include <linux/bootmem.h> -#include <linux/highmem.h> -#include <linux/dma-mapping.h> -#include <linux/hardirq.h> - -#include <asm/pgalloc.h> -#include <asm/prom.h> -#include <asm/io.h> -#include <asm/mmu_context.h> -#include <asm/pgtable.h> -#include <asm/mmu.h> -#include <asm/uaccess.h> -#include <asm/smp.h> -#include <asm/machdep.h> - -int map_page(unsigned long va, phys_addr_t pa, int flags); - -#include <asm/tlbflush.h> - -/* - * This address range defaults to a value that is safe for all - * platforms which currently set CONFIG_NOT_COHERENT_CACHE. It - * can be further configured for specific applications under - * the "Advanced Setup" menu. -Matt - */ -#define CONSISTENT_BASE (CONFIG_CONSISTENT_START) -#define CONSISTENT_END (CONFIG_CONSISTENT_START + CONFIG_CONSISTENT_SIZE) -#define CONSISTENT_OFFSET(x) (((unsigned long)(x) - CONSISTENT_BASE) >> PAGE_SHIFT) - -/* - * This is the page table (2MB) covering uncached, DMA consistent allocations - */ -static pte_t *consistent_pte; -static DEFINE_SPINLOCK(consistent_lock); - -/* - * VM region handling support. - * - * This should become something generic, handling VM region allocations for - * vmalloc and similar (ioremap, module space, etc). - * - * I envisage vmalloc()'s supporting vm_struct becoming: - * - * struct vm_struct { - * struct vm_region region; - * unsigned long flags; - * struct page **pages; - * unsigned int nr_pages; - * unsigned long phys_addr; - * }; - * - * get_vm_area() would then call vm_region_alloc with an appropriate - * struct vm_region head (eg): - * - * struct vm_region vmalloc_head = { - * .vm_list = LIST_HEAD_INIT(vmalloc_head.vm_list), - * .vm_start = VMALLOC_START, - * .vm_end = VMALLOC_END, - * }; - * - * However, vmalloc_head.vm_start is variable (typically, it is dependent on - * the amount of RAM found at boot time.) I would imagine that get_vm_area() - * would have to initialise this each time prior to calling vm_region_alloc(). - */ -struct vm_region { - struct list_head vm_list; - unsigned long vm_start; - unsigned long vm_end; -}; - -static struct vm_region consistent_head = { - .vm_list = LIST_HEAD_INIT(consistent_head.vm_list), - .vm_start = CONSISTENT_BASE, - .vm_end = CONSISTENT_END, -}; - -static struct vm_region * -vm_region_alloc(struct vm_region *head, size_t size, gfp_t gfp) -{ - unsigned long addr = head->vm_start, end = head->vm_end - size; - unsigned long flags; - struct vm_region *c, *new; - - new = kmalloc(sizeof(struct vm_region), gfp); - if (!new) - goto out; - - spin_lock_irqsave(&consistent_lock, flags); - - list_for_each_entry(c, &head->vm_list, vm_list) { - if ((addr + size) < addr) - goto nospc; - if ((addr + size) <= c->vm_start) - goto found; - addr = c->vm_end; - if (addr > end) - goto nospc; - } - - found: - /* - * Insert this entry _before_ the one we found. - */ - list_add_tail(&new->vm_list, &c->vm_list); - new->vm_start = addr; - new->vm_end = addr + size; - - spin_unlock_irqrestore(&consistent_lock, flags); - return new; - - nospc: - spin_unlock_irqrestore(&consistent_lock, flags); - kfree(new); - out: - return NULL; -} - -static struct vm_region *vm_region_find(struct vm_region *head, unsigned long addr) -{ - struct vm_region *c; - - list_for_each_entry(c, &head->vm_list, vm_list) { - if (c->vm_start == addr) - goto out; - } - c = NULL; - out: - return c; -} - -/* - * Allocate DMA-coherent memory space and return both the kernel remapped - * virtual and bus address for that space. - */ -void * -__dma_alloc_coherent(size_t size, dma_addr_t *handle, gfp_t gfp) -{ - struct page *page; - struct vm_region *c; - unsigned long order; - u64 mask = 0x00ffffff, limit; /* ISA default */ - - if (!consistent_pte) { - printk(KERN_ERR "%s: not initialised\n", __func__); - dump_stack(); - return NULL; - } - - size = PAGE_ALIGN(size); - limit = (mask + 1) & ~mask; - if ((limit && size >= limit) || size >= (CONSISTENT_END - CONSISTENT_BASE)) { - printk(KERN_WARNING "coherent allocation too big (requested %#x mask %#Lx)\n", - size, mask); - return NULL; - } - - order = get_order(size); - - if (mask != 0xffffffff) - gfp |= GFP_DMA; - - page = alloc_pages(gfp, order); - if (!page) - goto no_page; - - /* - * Invalidate any data that might be lurking in the - * kernel direct-mapped region for device DMA. - */ - { - unsigned long kaddr = (unsigned long)page_address(page); - memset(page_address(page), 0, size); - flush_dcache_range(kaddr, kaddr + size); - } - - /* - * Allocate a virtual address in the consistent mapping region. - */ - c = vm_region_alloc(&consistent_head, size, - gfp & ~(__GFP_DMA | __GFP_HIGHMEM)); - if (c) { - unsigned long vaddr = c->vm_start; - pte_t *pte = consistent_pte + CONSISTENT_OFFSET(vaddr); - struct page *end = page + (1 << order); - - split_page(page, order); - - /* - * Set the "dma handle" - */ - *handle = page_to_bus(page); - - do { - BUG_ON(!pte_none(*pte)); - - SetPageReserved(page); - set_pte_at(&init_mm, vaddr, - pte, mk_pte(page, pgprot_noncached(PAGE_KERNEL))); - page++; - pte++; - vaddr += PAGE_SIZE; - } while (size -= PAGE_SIZE); - - /* - * Free the otherwise unused pages. - */ - while (page < end) { - __free_page(page); - page++; - } - - return (void *)c->vm_start; - } - - if (page) - __free_pages(page, order); - no_page: - return NULL; -} -EXPORT_SYMBOL(__dma_alloc_coherent); - -/* - * free a page as defined by the above mapping. - */ -void __dma_free_coherent(size_t size, void *vaddr) -{ - struct vm_region *c; - unsigned long flags, addr; - pte_t *ptep; - - size = PAGE_ALIGN(size); - - spin_lock_irqsave(&consistent_lock, flags); - - c = vm_region_find(&consistent_head, (unsigned long)vaddr); - if (!c) - goto no_area; - - if ((c->vm_end - c->vm_start) != size) { - printk(KERN_ERR "%s: freeing wrong coherent size (%ld != %d)\n", - __func__, c->vm_end - c->vm_start, size); - dump_stack(); - size = c->vm_end - c->vm_start; - } - - ptep = consistent_pte + CONSISTENT_OFFSET(c->vm_start); - addr = c->vm_start; - do { - pte_t pte = ptep_get_and_clear(&init_mm, addr, ptep); - unsigned long pfn; - - ptep++; - addr += PAGE_SIZE; - - if (!pte_none(pte) && pte_present(pte)) { - pfn = pte_pfn(pte); - - if (pfn_valid(pfn)) { - struct page *page = pfn_to_page(pfn); - ClearPageReserved(page); - - __free_page(page); - continue; - } - } - - printk(KERN_CRIT "%s: bad page in kernel page table\n", - __func__); - } while (size -= PAGE_SIZE); - - flush_tlb_kernel_range(c->vm_start, c->vm_end); - - list_del(&c->vm_list); - - spin_unlock_irqrestore(&consistent_lock, flags); - - kfree(c); - return; - - no_area: - spin_unlock_irqrestore(&consistent_lock, flags); - printk(KERN_ERR "%s: trying to free invalid coherent area: %p\n", - __func__, vaddr); - dump_stack(); -} -EXPORT_SYMBOL(__dma_free_coherent); - -/* - * Initialise the consistent memory allocation. - */ -static int __init dma_alloc_init(void) -{ - pgd_t *pgd; - pmd_t *pmd; - pte_t *pte; - int ret = 0; - - do { - pgd = pgd_offset(&init_mm, CONSISTENT_BASE); - pmd = pmd_alloc(&init_mm, pgd, CONSISTENT_BASE); - if (!pmd) { - printk(KERN_ERR "%s: no pmd tables\n", __func__); - ret = -ENOMEM; - break; - } - WARN_ON(!pmd_none(*pmd)); - - pte = pte_alloc_kernel(pmd, CONSISTENT_BASE); - if (!pte) { - printk(KERN_ERR "%s: no pte tables\n", __func__); - ret = -ENOMEM; - break; - } - - consistent_pte = pte; - } while (0); - - return ret; -} - -core_initcall(dma_alloc_init); - -/* - * make an area consistent. - */ -void __dma_sync(void *vaddr, size_t size, int direction) -{ - unsigned long start = (unsigned long)vaddr; - unsigned long end = start + size; - - switch (direction) { - case DMA_NONE: - BUG(); - case DMA_FROM_DEVICE: /* invalidate only */ - invalidate_dcache_range(start, end); - break; - case DMA_TO_DEVICE: /* writeback only */ - clean_dcache_range(start, end); - break; - case DMA_BIDIRECTIONAL: /* writeback and invalidate */ - flush_dcache_range(start, end); - break; - } -} -EXPORT_SYMBOL(__dma_sync); - -#ifdef CONFIG_HIGHMEM -/* - * __dma_sync_page() implementation for systems using highmem. - * In this case, each page of a buffer must be kmapped/kunmapped - * in order to have a virtual address for __dma_sync(). This must - * not sleep so kmap_atomic()/kunmap_atomic() are used. - * - * Note: yes, it is possible and correct to have a buffer extend - * beyond the first page. - */ -static inline void __dma_sync_page_highmem(struct page *page, - unsigned long offset, size_t size, int direction) -{ - size_t seg_size = min((size_t)(PAGE_SIZE - offset), size); - size_t cur_size = seg_size; - unsigned long flags, start, seg_offset = offset; - int nr_segs = 1 + ((size - seg_size) + PAGE_SIZE - 1)/PAGE_SIZE; - int seg_nr = 0; - - local_irq_save(flags); - - do { - start = (unsigned long)kmap_atomic(page + seg_nr, - KM_PPC_SYNC_PAGE) + seg_offset; - - /* Sync this buffer segment */ - __dma_sync((void *)start, seg_size, direction); - kunmap_atomic((void *)start, KM_PPC_SYNC_PAGE); - seg_nr++; - - /* Calculate next buffer segment size */ - seg_size = min((size_t)PAGE_SIZE, size - cur_size); - - /* Add the segment size to our running total */ - cur_size += seg_size; - seg_offset = 0; - } while (seg_nr < nr_segs); - - local_irq_restore(flags); -} -#endif /* CONFIG_HIGHMEM */ - -/* - * __dma_sync_page makes memory consistent. identical to __dma_sync, but - * takes a struct page instead of a virtual address - */ -void __dma_sync_page(struct page *page, unsigned long offset, - size_t size, int direction) -{ -#ifdef CONFIG_HIGHMEM - __dma_sync_page_highmem(page, offset, size, direction); -#else - unsigned long start = (unsigned long)page_address(page) + offset; - __dma_sync((void *)start, size, direction); -#endif -} -EXPORT_SYMBOL(__dma_sync_page); |