diff options
Diffstat (limited to 'arch/powerpc/mm/dma-noncoherent.c')
-rw-r--r-- | arch/powerpc/mm/dma-noncoherent.c | 108 |
1 files changed, 41 insertions, 67 deletions
diff --git a/arch/powerpc/mm/dma-noncoherent.c b/arch/powerpc/mm/dma-noncoherent.c index b7dc4c1..36692f5 100644 --- a/arch/powerpc/mm/dma-noncoherent.c +++ b/arch/powerpc/mm/dma-noncoherent.c @@ -32,20 +32,21 @@ #include <asm/tlbflush.h> +#include "mmu_decl.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_BASE (IOREMAP_TOP) +#define CONSISTENT_END (CONSISTENT_BASE + 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); /* @@ -148,22 +149,38 @@ static struct ppc_vm_region *ppc_vm_region_find(struct ppc_vm_region *head, unsi * virtual and bus address for that space. */ void * -__dma_alloc_coherent(size_t size, dma_addr_t *handle, gfp_t gfp) +__dma_alloc_coherent(struct device *dev, size_t size, dma_addr_t *handle, gfp_t gfp) { struct page *page; struct ppc_vm_region *c; unsigned long order; - u64 mask = 0x00ffffff, limit; /* ISA default */ + u64 mask = ISA_DMA_THRESHOLD, limit; - if (!consistent_pte) { - printk(KERN_ERR "%s: not initialised\n", __func__); - dump_stack(); - return NULL; + if (dev) { + mask = dev->coherent_dma_mask; + + /* + * Sanity check the DMA mask - it must be non-zero, and + * must be able to be satisfied by a DMA allocation. + */ + if (mask == 0) { + dev_warn(dev, "coherent DMA mask is unset\n"); + goto no_page; + } + + if ((~mask) & ISA_DMA_THRESHOLD) { + dev_warn(dev, "coherent DMA mask %#llx is smaller " + "than system GFP_DMA mask %#llx\n", + mask, (unsigned long long)ISA_DMA_THRESHOLD); + goto no_page; + } } + size = PAGE_ALIGN(size); limit = (mask + 1) & ~mask; - if ((limit && size >= limit) || size >= (CONSISTENT_END - CONSISTENT_BASE)) { + 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; @@ -171,6 +188,7 @@ __dma_alloc_coherent(size_t size, dma_addr_t *handle, gfp_t gfp) order = get_order(size); + /* Might be useful if we ever have a real legacy DMA zone... */ if (mask != 0xffffffff) gfp |= GFP_DMA; @@ -195,7 +213,6 @@ __dma_alloc_coherent(size_t size, dma_addr_t *handle, gfp_t gfp) 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); @@ -206,13 +223,10 @@ __dma_alloc_coherent(size_t size, dma_addr_t *handle, gfp_t gfp) *handle = page_to_phys(page); do { - BUG_ON(!pte_none(*pte)); - SetPageReserved(page); - set_pte_at(&init_mm, vaddr, - pte, mk_pte(page, pgprot_noncached(PAGE_KERNEL))); + map_page(vaddr, page_to_phys(page), + pgprot_noncached(PAGE_KERNEL)); page++; - pte++; vaddr += PAGE_SIZE; } while (size -= PAGE_SIZE); @@ -241,8 +255,7 @@ void __dma_free_coherent(size_t size, void *vaddr) { struct ppc_vm_region *c; unsigned long flags, addr; - pte_t *ptep; - + size = PAGE_ALIGN(size); spin_lock_irqsave(&consistent_lock, flags); @@ -258,29 +271,26 @@ void __dma_free_coherent(size_t size, void *vaddr) 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); + pte_t *ptep; unsigned long pfn; - ptep++; - addr += PAGE_SIZE; - - if (!pte_none(pte) && pte_present(pte)) { - pfn = pte_pfn(pte); - + ptep = pte_offset_kernel(pmd_offset(pud_offset(pgd_offset_k(addr), + addr), + addr), + addr); + if (!pte_none(*ptep) && pte_present(*ptep)) { + pfn = pte_pfn(*ptep); + pte_clear(&init_mm, addr, ptep); if (pfn_valid(pfn)) { struct page *page = pfn_to_page(pfn); - ClearPageReserved(page); + ClearPageReserved(page); __free_page(page); - continue; } } - - printk(KERN_CRIT "%s: bad page in kernel page table\n", - __func__); + addr += PAGE_SIZE; } while (size -= PAGE_SIZE); flush_tlb_kernel_range(c->vm_start, c->vm_end); @@ -301,42 +311,6 @@ void __dma_free_coherent(size_t size, void *vaddr) EXPORT_SYMBOL(__dma_free_coherent); /* - * Initialise the consistent memory allocation. - */ -static int __init dma_alloc_init(void) -{ - pgd_t *pgd; - pud_t *pud; - pmd_t *pmd; - pte_t *pte; - int ret = 0; - - do { - pgd = pgd_offset(&init_mm, CONSISTENT_BASE); - pud = pud_alloc(&init_mm, pgd, CONSISTENT_BASE); - pmd = pmd_alloc(&init_mm, pud, CONSISTENT_BASE); - if (!pmd) { - printk(KERN_ERR "%s: no pmd tables\n", __func__); - ret = -ENOMEM; - break; - } - - 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) |