diff options
Diffstat (limited to 'arch/arm/mm/dma-mapping.c')
| -rw-r--r-- | arch/arm/mm/dma-mapping.c | 83 |
1 files changed, 68 insertions, 15 deletions
diff --git a/arch/arm/mm/dma-mapping.c b/arch/arm/mm/dma-mapping.c index 82a093cee09a..e4e7f6cba1ab 100644 --- a/arch/arm/mm/dma-mapping.c +++ b/arch/arm/mm/dma-mapping.c @@ -18,16 +18,20 @@ #include <linux/device.h> #include <linux/dma-mapping.h> #include <linux/highmem.h> +#include <linux/slab.h> #include <asm/memory.h> #include <asm/highmem.h> #include <asm/cacheflush.h> #include <asm/tlbflush.h> #include <asm/sizes.h> +#include <asm/mach/arch.h> + +#include "mm.h" static u64 get_coherent_dma_mask(struct device *dev) { - u64 mask = ISA_DMA_THRESHOLD; + u64 mask = (u64)arm_dma_limit; if (dev) { mask = dev->coherent_dma_mask; @@ -41,10 +45,10 @@ static u64 get_coherent_dma_mask(struct device *dev) return 0; } - if ((~mask) & ISA_DMA_THRESHOLD) { + if ((~mask) & (u64)arm_dma_limit) { dev_warn(dev, "coherent DMA mask %#llx is smaller " "than system GFP_DMA mask %#llx\n", - mask, (unsigned long long)ISA_DMA_THRESHOLD); + mask, (u64)arm_dma_limit); return 0; } } @@ -115,26 +119,36 @@ static void __dma_free_buffer(struct page *page, size_t size) } #ifdef CONFIG_MMU -/* Sanity check size */ -#if (CONSISTENT_DMA_SIZE % SZ_2M) -#error "CONSISTENT_DMA_SIZE must be multiple of 2MiB" -#endif -#define CONSISTENT_OFFSET(x) (((unsigned long)(x) - CONSISTENT_BASE) >> PAGE_SHIFT) -#define CONSISTENT_PTE_INDEX(x) (((unsigned long)(x) - CONSISTENT_BASE) >> PGDIR_SHIFT) -#define NUM_CONSISTENT_PTES (CONSISTENT_DMA_SIZE >> PGDIR_SHIFT) +#define CONSISTENT_OFFSET(x) (((unsigned long)(x) - consistent_base) >> PAGE_SHIFT) +#define CONSISTENT_PTE_INDEX(x) (((unsigned long)(x) - consistent_base) >> PMD_SHIFT) /* * These are the page tables (2MB each) covering uncached, DMA consistent allocations */ -static pte_t *consistent_pte[NUM_CONSISTENT_PTES]; +static pte_t **consistent_pte; + +#define DEFAULT_CONSISTENT_DMA_SIZE SZ_2M + +unsigned long consistent_base = CONSISTENT_END - DEFAULT_CONSISTENT_DMA_SIZE; + +void __init init_consistent_dma_size(unsigned long size) +{ + unsigned long base = CONSISTENT_END - ALIGN(size, SZ_2M); + + BUG_ON(consistent_pte); /* Check we're called before DMA region init */ + BUG_ON(base < VMALLOC_END); + + /* Grow region to accommodate specified size */ + if (base < consistent_base) + consistent_base = base; +} #include "vmregion.h" static struct arm_vmregion_head consistent_head = { .vm_lock = __SPIN_LOCK_UNLOCKED(&consistent_head.vm_lock), .vm_list = LIST_HEAD_INIT(consistent_head.vm_list), - .vm_start = CONSISTENT_BASE, .vm_end = CONSISTENT_END, }; @@ -153,7 +167,17 @@ static int __init consistent_init(void) pmd_t *pmd; pte_t *pte; int i = 0; - u32 base = CONSISTENT_BASE; + unsigned long base = consistent_base; + unsigned long num_ptes = (CONSISTENT_END - base) >> PGDIR_SHIFT; + + consistent_pte = kmalloc(num_ptes * sizeof(pte_t), GFP_KERNEL); + if (!consistent_pte) { + pr_err("%s: no memory\n", __func__); + return -ENOMEM; + } + + pr_debug("DMA memory: 0x%08lx - 0x%08lx:\n", base, CONSISTENT_END); + consistent_head.vm_start = base; do { pgd = pgd_offset(&init_mm, base); @@ -181,7 +205,7 @@ static int __init consistent_init(void) } consistent_pte[i++] = pte; - base += (1 << PGDIR_SHIFT); + base += PMD_SIZE; } while (base < CONSISTENT_END); return ret; @@ -196,7 +220,7 @@ __dma_alloc_remap(struct page *page, size_t size, gfp_t gfp, pgprot_t prot) size_t align; int bit; - if (!consistent_pte[0]) { + if (!consistent_pte) { printk(KERN_ERR "%s: not initialised\n", __func__); dump_stack(); return NULL; @@ -322,6 +346,8 @@ __dma_alloc(struct device *dev, size_t size, dma_addr_t *handle, gfp_t gfp, if (addr) *handle = pfn_to_dma(dev, page_to_pfn(page)); + else + __dma_free_buffer(page, size); return addr; } @@ -657,6 +683,33 @@ void dma_sync_sg_for_device(struct device *dev, struct scatterlist *sg, } EXPORT_SYMBOL(dma_sync_sg_for_device); +/* + * Return whether the given device DMA address mask can be supported + * properly. For example, if your device can only drive the low 24-bits + * during bus mastering, then you would pass 0x00ffffff as the mask + * to this function. + */ +int dma_supported(struct device *dev, u64 mask) +{ + if (mask < (u64)arm_dma_limit) + return 0; + return 1; +} +EXPORT_SYMBOL(dma_supported); + +int dma_set_mask(struct device *dev, u64 dma_mask) +{ + if (!dev->dma_mask || !dma_supported(dev, dma_mask)) + return -EIO; + +#ifndef CONFIG_DMABOUNCE + *dev->dma_mask = dma_mask; +#endif + + return 0; +} +EXPORT_SYMBOL(dma_set_mask); + #define PREALLOC_DMA_DEBUG_ENTRIES 4096 static int __init dma_debug_do_init(void) |