diff --git a/Documentation/DMA-API-HOWTO.txt b/Documentation/DMA-API-HOWTO.txt index 14129f149a75..5e983031cc11 100644 --- a/Documentation/DMA-API-HOWTO.txt +++ b/Documentation/DMA-API-HOWTO.txt @@ -101,14 +101,23 @@ style to do this even if your device holds the default setting, because this shows that you did think about these issues wrt. your device. -The query is performed via a call to dma_set_mask(): +The query is performed via a call to dma_set_mask_and_coherent(): - int dma_set_mask(struct device *dev, u64 mask); + int dma_set_mask_and_coherent(struct device *dev, u64 mask); -The query for consistent allocations is performed via a call to -dma_set_coherent_mask(): +which will query the mask for both streaming and coherent APIs together. +If you have some special requirements, then the following two separate +queries can be used instead: - int dma_set_coherent_mask(struct device *dev, u64 mask); + The query for streaming mappings is performed via a call to + dma_set_mask(): + + int dma_set_mask(struct device *dev, u64 mask); + + The query for consistent allocations is performed via a call + to dma_set_coherent_mask(): + + int dma_set_coherent_mask(struct device *dev, u64 mask); Here, dev is a pointer to the device struct of your device, and mask is a bit mask describing which bits of an address your device @@ -137,7 +146,7 @@ exactly why. The standard 32-bit addressing device would do something like this: - if (dma_set_mask(dev, DMA_BIT_MASK(32))) { + if (dma_set_mask_and_coherent(dev, DMA_BIT_MASK(32))) { printk(KERN_WARNING "mydev: No suitable DMA available.\n"); goto ignore_this_device; @@ -171,22 +180,20 @@ the case would look like this: int using_dac, consistent_using_dac; - if (!dma_set_mask(dev, DMA_BIT_MASK(64))) { + if (!dma_set_mask_and_coherent(dev, DMA_BIT_MASK(64))) { using_dac = 1; consistent_using_dac = 1; - dma_set_coherent_mask(dev, DMA_BIT_MASK(64)); - } else if (!dma_set_mask(dev, DMA_BIT_MASK(32))) { + } else if (!dma_set_mask_and_coherent(dev, DMA_BIT_MASK(32))) { using_dac = 0; consistent_using_dac = 0; - dma_set_coherent_mask(dev, DMA_BIT_MASK(32)); } else { printk(KERN_WARNING "mydev: No suitable DMA available.\n"); goto ignore_this_device; } -dma_set_coherent_mask() will always be able to set the same or a -smaller mask as dma_set_mask(). However for the rare case that a +The coherent coherent mask will always be able to set the same or a +smaller mask as the streaming mask. However for the rare case that a device driver only uses consistent allocations, one would have to check the return value from dma_set_coherent_mask(). @@ -199,9 +206,9 @@ address you might do something like: goto ignore_this_device; } -When dma_set_mask() is successful, and returns zero, the kernel saves -away this mask you have provided. The kernel will use this -information later when you make DMA mappings. +When dma_set_mask() or dma_set_mask_and_coherent() is successful, and +returns zero, the kernel saves away this mask you have provided. The +kernel will use this information later when you make DMA mappings. There is a case which we are aware of at this time, which is worth mentioning in this documentation. If your device supports multiple diff --git a/Documentation/DMA-API.txt b/Documentation/DMA-API.txt index 78a6c569d204..e865279cec58 100644 --- a/Documentation/DMA-API.txt +++ b/Documentation/DMA-API.txt @@ -141,6 +141,14 @@ won't change the current mask settings. It is more intended as an internal API for use by the platform than an external API for use by driver writers. +int +dma_set_mask_and_coherent(struct device *dev, u64 mask) + +Checks to see if the mask is possible and updates the device +streaming and coherent DMA mask parameters if it is. + +Returns: 0 if successful and a negative error if not. + int dma_set_mask(struct device *dev, u64 mask) diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig index 1308d8d1177c..5ee96e17c63c 100644 --- a/arch/arm64/Kconfig +++ b/arch/arm64/Kconfig @@ -82,7 +82,7 @@ config GENERIC_CSUM config GENERIC_CALIBRATE_DELAY def_bool y -config ZONE_DMA32 +config ZONE_DMA def_bool y config ARCH_DMA_ADDR_T_64BIT diff --git a/arch/arm64/mm/cache.S b/arch/arm64/mm/cache.S index 4726b8209d37..39b6542b138e 100644 --- a/arch/arm64/mm/cache.S +++ b/arch/arm64/mm/cache.S @@ -175,12 +175,19 @@ ENDPROC(__flush_dcache_area) __dma_inv_range: dcache_line_size x2, x3 sub x3, x2, #1 - bic x0, x0, x3 + tst x1, x3 // end cache line aligned? bic x1, x1, x3 -1: dc ivac, x0 // invalidate D / U line - add x0, x0, x2 + b.eq 1f + dc civac, x1 // clean & invalidate D / U line +1: tst x0, x3 // start cache line aligned? + bic x0, x0, x3 + b.eq 2f + dc civac, x0 // clean & invalidate D / U line + b 3f +2: dc ivac, x0 // invalidate D / U line +3: add x0, x0, x2 cmp x0, x1 - b.lo 1b + b.lo 2b dsb sy ret ENDPROC(__dma_inv_range) diff --git a/arch/arm64/mm/dma-mapping.c b/arch/arm64/mm/dma-mapping.c index 550873ace597..d3d9bf5884f8 100644 --- a/arch/arm64/mm/dma-mapping.c +++ b/arch/arm64/mm/dma-mapping.c @@ -34,9 +34,9 @@ static void *__dma_alloc_coherent(struct device *dev, size_t size, dma_addr_t *dma_handle, gfp_t flags, struct dma_attrs *attrs) { - if (IS_ENABLED(CONFIG_ZONE_DMA32) && + if (IS_ENABLED(CONFIG_ZONE_DMA) && dev->coherent_dma_mask <= DMA_BIT_MASK(32)) - flags |= GFP_DMA32; + flags |= GFP_DMA; if (IS_ENABLED(CONFIG_DMA_CMA)) { struct page *page; @@ -248,11 +248,17 @@ struct dma_map_ops coherent_swiotlb_dma_ops = { }; EXPORT_SYMBOL(coherent_swiotlb_dma_ops); -void __init arm64_swiotlb_init(void) +extern int swiotlb_late_init_with_default_size(size_t default_size); + +static int __init swiotlb_late_init(void) { - dma_ops = &coherent_swiotlb_dma_ops; - swiotlb_init(1); + size_t swiotlb_size = min(SZ_64M, MAX_ORDER_NR_PAGES << PAGE_SHIFT); + + dma_ops = &noncoherent_swiotlb_dma_ops; + + return swiotlb_late_init_with_default_size(swiotlb_size); } +subsys_initcall(swiotlb_late_init); #define PREALLOC_DMA_DEBUG_ENTRIES 4096 diff --git a/arch/arm64/mm/init.c b/arch/arm64/mm/init.c index 851d3c137e03..fa3651855334 100644 --- a/arch/arm64/mm/init.c +++ b/arch/arm64/mm/init.c @@ -30,6 +30,7 @@ #include #include #include +#include #include #include @@ -68,22 +69,22 @@ static int __init early_initrd(char *p) } early_param("initrd", early_initrd); -#define MAX_DMA32_PFN ((4UL * 1024 * 1024 * 1024) >> PAGE_SHIFT) - static void __init zone_sizes_init(unsigned long min, unsigned long max) { struct memblock_region *reg; unsigned long zone_size[MAX_NR_ZONES], zhole_size[MAX_NR_ZONES]; - unsigned long max_dma32 = min; + unsigned long max_dma = min; memset(zone_size, 0, sizeof(zone_size)); -#ifdef CONFIG_ZONE_DMA32 /* 4GB maximum for 32-bit only capable devices */ - max_dma32 = max(min, min(max, MAX_DMA32_PFN)); - zone_size[ZONE_DMA32] = max_dma32 - min; -#endif - zone_size[ZONE_NORMAL] = max - max_dma32; + if (IS_ENABLED(CONFIG_ZONE_DMA)) { + unsigned long max_dma_phys = + (unsigned long)dma_to_phys(NULL, DMA_BIT_MASK(32) + 1); + max_dma = max(min, min(max, max_dma_phys >> PAGE_SHIFT)); + zone_size[ZONE_DMA] = max_dma - min; + } + zone_size[ZONE_NORMAL] = max - max_dma; memcpy(zhole_size, zone_size, sizeof(zhole_size)); @@ -93,15 +94,15 @@ static void __init zone_sizes_init(unsigned long min, unsigned long max) if (start >= max) continue; -#ifdef CONFIG_ZONE_DMA32 - if (start < max_dma32) { - unsigned long dma_end = min(end, max_dma32); - zhole_size[ZONE_DMA32] -= dma_end - start; + + if (IS_ENABLED(CONFIG_ZONE_DMA) && start < max_dma) { + unsigned long dma_end = min(end, max_dma); + zhole_size[ZONE_DMA] -= dma_end - start; } -#endif - if (end > max_dma32) { + + if (end > max_dma) { unsigned long normal_end = min(end, max); - unsigned long normal_start = max(start, max_dma32); + unsigned long normal_start = max(start, max_dma); zhole_size[ZONE_NORMAL] -= normal_end - normal_start; } } @@ -286,8 +287,6 @@ void __init mem_init(void) unsigned long reserved_pages, free_pages; struct memblock_region *reg; - arm64_swiotlb_init(); - max_mapnr = pfn_to_page(max_pfn + PHYS_PFN_OFFSET) - mem_map; #ifndef CONFIG_SPARSEMEM_VMEMMAP diff --git a/include/linux/dma-mapping.h b/include/linux/dma-mapping.h index 94af41858513..48ef6f50d86c 100644 --- a/include/linux/dma-mapping.h +++ b/include/linux/dma-mapping.h @@ -97,6 +97,30 @@ 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; +} + +/* + * 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)