ARM: dma: replace ISA_DMA_THRESHOLD with a variable

ISA_DMA_THRESHOLD has been unused by non-arch code, so lets now get
rid of it from ARM by replacing it with arm_dma_zone_mask.  Move
dma_supported() and dma_set_mask() out of line, and have
dma_supported() check this new variable instead.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
This commit is contained in:
Russell King 2011-07-08 21:26:59 +01:00
parent 3973c33775
commit 022ae537b2
5 changed files with 50 additions and 42 deletions

View File

@ -115,33 +115,8 @@ static inline void __dma_page_dev_to_cpu(struct page *page, unsigned long off,
___dma_page_dev_to_cpu(page, off, size, dir);
}
/*
* 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.
*
* FIXME: This should really be a platform specific issue - we should
* return false if GFP_DMA allocations may not satisfy the supplied 'mask'.
*/
static inline int dma_supported(struct device *dev, u64 mask)
{
if (mask < ISA_DMA_THRESHOLD)
return 0;
return 1;
}
static inline 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;
}
extern int dma_supported(struct device *, u64);
extern int dma_set_mask(struct device *, u64);
/*
* DMA errors are defined by all-bits-set in the DMA address.

View File

@ -203,18 +203,6 @@ static inline unsigned long __phys_to_virt(unsigned long x)
#define PHYS_OFFSET PLAT_PHYS_OFFSET
#endif
/*
* The DMA mask corresponding to the maximum bus address allocatable
* using GFP_DMA. The default here places no restriction on DMA
* allocations. This must be the smallest DMA mask in the system,
* so a successful GFP_DMA allocation will always satisfy this.
*/
#ifndef ARM_DMA_ZONE_SIZE
#define ISA_DMA_THRESHOLD (0xffffffffULL)
#else
#define ISA_DMA_THRESHOLD (PHYS_OFFSET + ARM_DMA_ZONE_SIZE - 1)
#endif
/*
* PFNs are used to describe any physical page; this means
* PFN 0 == physical address 0.

View File

@ -25,9 +25,11 @@
#include <asm/tlbflush.h>
#include <asm/sizes.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 +43,10 @@ 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;
}
}
@ -657,6 +659,33 @@ 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)

View File

@ -212,6 +212,14 @@ static void __init arm_bootmem_init(unsigned long start_pfn,
}
#ifdef CONFIG_ZONE_DMA
/*
* The DMA mask corresponding to the maximum bus address allocatable
* using GFP_DMA. The default here places no restriction on DMA
* allocations. This must be the smallest DMA mask in the system,
* so a successful GFP_DMA allocation will always satisfy this.
*/
u32 arm_dma_limit;
static void __init arm_adjust_dma_zone(unsigned long *size, unsigned long *hole,
unsigned long dma_size)
{
@ -278,6 +286,8 @@ static void __init arm_bootmem_free(unsigned long min, unsigned long max_low,
*/
arm_adjust_dma_zone(zone_size, zhole_size,
ARM_DMA_ZONE_SIZE >> PAGE_SHIFT);
arm_dma_limit = PHYS_OFFSET + ARM_DMA_ZONE_SIZE - 1;
#endif
free_area_init_node(0, zone_size, min, zhole_size);

View File

@ -23,5 +23,11 @@ extern void __flush_dcache_page(struct address_space *mapping, struct page *page
#endif
#ifdef CONFIG_ZONE_DMA
extern u32 arm_dma_limit;
#else
#define arm_dma_limit ((u32)~0)
#endif
void __init bootmem_init(void);
void arm_mm_memblock_reserve(void);