From 4aa806b771d16b810771d86ce23c4c3160888db3 Mon Sep 17 00:00:00 2001 From: Russell King Date: Wed, 26 Jun 2013 13:49:44 +0100 Subject: DMA-API: provide a helper to set both DMA and coherent DMA masks Provide a helper to set both the DMA and coherent DMA masks to the same value - this avoids duplicated code in a number of drivers, sometimes with buggy error handling, and also allows us identify which drivers do things differently. Signed-off-by: Russell King --- include/linux/dma-mapping.h | 14 ++++++++++++++ 1 file changed, 14 insertions(+) (limited to 'include') diff --git a/include/linux/dma-mapping.h b/include/linux/dma-mapping.h index 3a8d0a2af607..ec951f98e3d9 100644 --- a/include/linux/dma-mapping.h +++ b/include/linux/dma-mapping.h @@ -97,6 +97,20 @@ static inline int dma_set_coherent_mask(struct device *dev, u64 mask) } #endif +/* + * Set both the DMA mask and the coherent DMA mask to the same thing. + * Note that we don't check the return value from dma_set_coherent_mask() + * as the DMA API guarantees that the coherent DMA mask can be set to + * the same or smaller than the streaming DMA mask. + */ +static inline int dma_set_mask_and_coherent(struct device *dev, u64 mask) +{ + int rc = dma_set_mask(dev, mask); + if (rc == 0) + dma_set_coherent_mask(dev, mask); + return rc; +} + extern u64 dma_get_required_mask(struct device *dev); static inline unsigned int dma_get_max_seg_size(struct device *dev) -- cgit v1.2.3 From 446b2a9380b64b9d7410d86ee8226031e03645cf Mon Sep 17 00:00:00 2001 From: Russell King Date: Thu, 27 Jun 2013 10:25:33 +0100 Subject: DMA-API: amba: get rid of separate dma_mask AMBA Primecell devices always treat streaming and coherent DMA exactly the same, so there's no point in having the masks separated. Acked-by: Grant Likely Signed-off-by: Russell King --- drivers/amba/bus.c | 6 +----- drivers/of/platform.c | 3 --- include/linux/amba/bus.h | 2 -- 3 files changed, 1 insertion(+), 10 deletions(-) (limited to 'include') diff --git a/drivers/amba/bus.c b/drivers/amba/bus.c index c6707278a6bb..c4876ac9151a 100644 --- a/drivers/amba/bus.c +++ b/drivers/amba/bus.c @@ -552,7 +552,6 @@ amba_aphb_device_add(struct device *parent, const char *name, if (!dev) return ERR_PTR(-ENOMEM); - dev->dma_mask = dma_mask; dev->dev.coherent_dma_mask = dma_mask; dev->irq[0] = irq1; dev->irq[1] = irq2; @@ -619,7 +618,7 @@ static void amba_device_initialize(struct amba_device *dev, const char *name) dev_set_name(&dev->dev, "%s", name); dev->dev.release = amba_device_release; dev->dev.bus = &amba_bustype; - dev->dev.dma_mask = &dev->dma_mask; + dev->dev.dma_mask = &dev->dev.coherent_dma_mask; dev->res.name = dev_name(&dev->dev); } @@ -663,9 +662,6 @@ int amba_device_register(struct amba_device *dev, struct resource *parent) amba_device_initialize(dev, dev->dev.init_name); dev->dev.init_name = NULL; - if (!dev->dev.coherent_dma_mask && dev->dma_mask) - dev_warn(&dev->dev, "coherent dma mask is unset\n"); - return amba_device_add(dev, parent); } diff --git a/drivers/of/platform.c b/drivers/of/platform.c index 9b439ac63d8e..54382ba4a6e9 100644 --- a/drivers/of/platform.c +++ b/drivers/of/platform.c @@ -284,9 +284,6 @@ static struct amba_device *of_amba_device_create(struct device_node *node, else of_device_make_bus_id(&dev->dev); - /* setup amba-specific device info */ - dev->dma_mask = ~0; - /* Allow the HW Peripheral ID to be overridden */ prop = of_get_property(node, "arm,primecell-periphid", NULL); if (prop) diff --git a/include/linux/amba/bus.h b/include/linux/amba/bus.h index 43ec7e247a80..682df0e1954a 100644 --- a/include/linux/amba/bus.h +++ b/include/linux/amba/bus.h @@ -30,7 +30,6 @@ struct amba_device { struct device dev; struct resource res; struct clk *pclk; - u64 dma_mask; unsigned int periphid; unsigned int irq[AMBA_NR_IRQS]; }; @@ -131,7 +130,6 @@ struct amba_device name##_device = { \ struct amba_device name##_device = { \ .dev = __AMBA_DEV(busid, data, ~0ULL), \ .res = DEFINE_RES_MEM(base, SZ_4K), \ - .dma_mask = ~0ULL, \ .irq = irqs, \ .periphid = id, \ } -- cgit v1.2.3 From fa6a8d6d65b19ab44e5244ea499bcd553cc72343 Mon Sep 17 00:00:00 2001 From: Russell King Date: Thu, 27 Jun 2013 12:21:45 +0100 Subject: DMA-API: provide a helper to setup DMA masks Many drivers contain code such as: dev->dma_mask = &dev->coherent_dma_mask; dev->coherent_dma_mask = MASK; Let's move this pattern out of drivers and have the DMA API provide a helper for it. This helper uses dma_set_mask_and_coherent() to allow platform issues to be properly dealt with via dma_set_mask()/ dma_is_supported(). Signed-off-by: Russell King --- include/linux/dma-mapping.h | 10 ++++++++++ 1 file changed, 10 insertions(+) (limited to 'include') diff --git a/include/linux/dma-mapping.h b/include/linux/dma-mapping.h index ec951f98e3d9..27d1421ad42c 100644 --- a/include/linux/dma-mapping.h +++ b/include/linux/dma-mapping.h @@ -111,6 +111,16 @@ static inline int dma_set_mask_and_coherent(struct device *dev, u64 mask) return rc; } +/* + * Similar to the above, except it deals with the case where the device + * does not have dev->dma_mask appropriately setup. + */ +static inline int dma_coerce_mask_and_coherent(struct device *dev, u64 mask) +{ + dev->dma_mask = &dev->coherent_dma_mask; + return dma_set_mask_and_coherent(dev, mask); +} + extern u64 dma_get_required_mask(struct device *dev); static inline unsigned int dma_get_max_seg_size(struct device *dev) -- cgit v1.2.3 From 00c8f1623658947a97345ecb86b71232ff540d0d Mon Sep 17 00:00:00 2001 From: Santosh Shilimkar Date: Mon, 29 Jul 2013 14:18:48 +0100 Subject: ARM: 7795/1: mm: dma-mapping: Add dma_max_pfn(dev) helper function Most of the kernel assumes that PFN0 is the start of the physical memory (RAM). This assumptions is not true on most of the ARM SOCs and hence and if one try to update the ARM port to follow the assumptions, we end of breaking the dma bounce limit for few block layer drivers. One such example is trying to unify the meaning of max*_pfn on ARM as the bootmem layer expects, breaks few block layer driver dma bounce limit. To fix this problem, we introduce dma_max_pfn(dev) generic helper with a possibility of override from the architecture code. The helper converts a DMA bitmask of bits to a block PFN number. In all the generic cases, it is just "dev->dma_mask >> PAGE_SHIFT" and hence default behavior is maintained as is. Subsequent patches will make use of the helper. No functional change. Cc: Jens Axboe Signed-off-by: Santosh Shilimkar Signed-off-by: Russell King --- include/linux/dma-mapping.h | 7 +++++++ 1 file changed, 7 insertions(+) (limited to 'include') diff --git a/include/linux/dma-mapping.h b/include/linux/dma-mapping.h index 27d1421ad42c..fd4aee29ad10 100644 --- a/include/linux/dma-mapping.h +++ b/include/linux/dma-mapping.h @@ -153,6 +153,13 @@ static inline int dma_set_seg_boundary(struct device *dev, unsigned long mask) return -EIO; } +#ifndef dma_max_pfn +static inline unsigned long dma_max_pfn(struct device *dev) +{ + return *dev->dma_mask >> PAGE_SHIFT; +} +#endif + static inline void *dma_zalloc_coherent(struct device *dev, size_t size, dma_addr_t *dma_handle, gfp_t flag) { -- cgit v1.2.3