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-rw-r--r--kernel/arch/mips/mm/dma-default.c396
1 files changed, 396 insertions, 0 deletions
diff --git a/kernel/arch/mips/mm/dma-default.c b/kernel/arch/mips/mm/dma-default.c
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+++ b/kernel/arch/mips/mm/dma-default.c
@@ -0,0 +1,396 @@
+/*
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License. See the file "COPYING" in the main directory of this archive
+ * for more details.
+ *
+ * Copyright (C) 2000 Ani Joshi <ajoshi@unixbox.com>
+ * Copyright (C) 2000, 2001, 06 Ralf Baechle <ralf@linux-mips.org>
+ * swiped from i386, and cloned for MIPS by Geert, polished by Ralf.
+ */
+
+#include <linux/types.h>
+#include <linux/dma-mapping.h>
+#include <linux/mm.h>
+#include <linux/module.h>
+#include <linux/scatterlist.h>
+#include <linux/string.h>
+#include <linux/gfp.h>
+#include <linux/highmem.h>
+#include <linux/dma-contiguous.h>
+
+#include <asm/cache.h>
+#include <asm/cpu-type.h>
+#include <asm/io.h>
+
+#include <dma-coherence.h>
+
+#ifdef CONFIG_DMA_MAYBE_COHERENT
+int coherentio = 0; /* User defined DMA coherency from command line. */
+EXPORT_SYMBOL_GPL(coherentio);
+int hw_coherentio = 0; /* Actual hardware supported DMA coherency setting. */
+
+static int __init setcoherentio(char *str)
+{
+ coherentio = 1;
+ pr_info("Hardware DMA cache coherency (command line)\n");
+ return 0;
+}
+early_param("coherentio", setcoherentio);
+
+static int __init setnocoherentio(char *str)
+{
+ coherentio = 0;
+ pr_info("Software DMA cache coherency (command line)\n");
+ return 0;
+}
+early_param("nocoherentio", setnocoherentio);
+#endif
+
+static inline struct page *dma_addr_to_page(struct device *dev,
+ dma_addr_t dma_addr)
+{
+ return pfn_to_page(
+ plat_dma_addr_to_phys(dev, dma_addr) >> PAGE_SHIFT);
+}
+
+/*
+ * The affected CPUs below in 'cpu_needs_post_dma_flush()' can
+ * speculatively fill random cachelines with stale data at any time,
+ * requiring an extra flush post-DMA.
+ *
+ * Warning on the terminology - Linux calls an uncached area coherent;
+ * MIPS terminology calls memory areas with hardware maintained coherency
+ * coherent.
+ *
+ * Note that the R14000 and R16000 should also be checked for in this
+ * condition. However this function is only called on non-I/O-coherent
+ * systems and only the R10000 and R12000 are used in such systems, the
+ * SGI IP28 Indigo² rsp. SGI IP32 aka O2.
+ */
+static inline int cpu_needs_post_dma_flush(struct device *dev)
+{
+ return !plat_device_is_coherent(dev) &&
+ (boot_cpu_type() == CPU_R10000 ||
+ boot_cpu_type() == CPU_R12000 ||
+ boot_cpu_type() == CPU_BMIPS5000);
+}
+
+static gfp_t massage_gfp_flags(const struct device *dev, gfp_t gfp)
+{
+ gfp_t dma_flag;
+
+ /* ignore region specifiers */
+ gfp &= ~(__GFP_DMA | __GFP_DMA32 | __GFP_HIGHMEM);
+
+#ifdef CONFIG_ISA
+ if (dev == NULL)
+ dma_flag = __GFP_DMA;
+ else
+#endif
+#if defined(CONFIG_ZONE_DMA32) && defined(CONFIG_ZONE_DMA)
+ if (dev->coherent_dma_mask < DMA_BIT_MASK(32))
+ dma_flag = __GFP_DMA;
+ else if (dev->coherent_dma_mask < DMA_BIT_MASK(64))
+ dma_flag = __GFP_DMA32;
+ else
+#endif
+#if defined(CONFIG_ZONE_DMA32) && !defined(CONFIG_ZONE_DMA)
+ if (dev->coherent_dma_mask < DMA_BIT_MASK(64))
+ dma_flag = __GFP_DMA32;
+ else
+#endif
+#if defined(CONFIG_ZONE_DMA) && !defined(CONFIG_ZONE_DMA32)
+ if (dev->coherent_dma_mask < DMA_BIT_MASK(64))
+ dma_flag = __GFP_DMA;
+ else
+#endif
+ dma_flag = 0;
+
+ /* Don't invoke OOM killer */
+ gfp |= __GFP_NORETRY;
+
+ return gfp | dma_flag;
+}
+
+void *dma_alloc_noncoherent(struct device *dev, size_t size,
+ dma_addr_t * dma_handle, gfp_t gfp)
+{
+ void *ret;
+
+ gfp = massage_gfp_flags(dev, gfp);
+
+ ret = (void *) __get_free_pages(gfp, get_order(size));
+
+ if (ret != NULL) {
+ memset(ret, 0, size);
+ *dma_handle = plat_map_dma_mem(dev, ret, size);
+ }
+
+ return ret;
+}
+EXPORT_SYMBOL(dma_alloc_noncoherent);
+
+static void *mips_dma_alloc_coherent(struct device *dev, size_t size,
+ dma_addr_t * dma_handle, gfp_t gfp, struct dma_attrs *attrs)
+{
+ void *ret;
+ struct page *page = NULL;
+ unsigned int count = PAGE_ALIGN(size) >> PAGE_SHIFT;
+
+ if (dma_alloc_from_coherent(dev, size, dma_handle, &ret))
+ return ret;
+
+ gfp = massage_gfp_flags(dev, gfp);
+
+ if (IS_ENABLED(CONFIG_DMA_CMA) && !(gfp & GFP_ATOMIC))
+ page = dma_alloc_from_contiguous(dev,
+ count, get_order(size));
+ if (!page)
+ page = alloc_pages(gfp, get_order(size));
+
+ if (!page)
+ return NULL;
+
+ ret = page_address(page);
+ memset(ret, 0, size);
+ *dma_handle = plat_map_dma_mem(dev, ret, size);
+ if (!plat_device_is_coherent(dev)) {
+ dma_cache_wback_inv((unsigned long) ret, size);
+ if (!hw_coherentio)
+ ret = UNCAC_ADDR(ret);
+ }
+
+ return ret;
+}
+
+
+void dma_free_noncoherent(struct device *dev, size_t size, void *vaddr,
+ dma_addr_t dma_handle)
+{
+ plat_unmap_dma_mem(dev, dma_handle, size, DMA_BIDIRECTIONAL);
+ free_pages((unsigned long) vaddr, get_order(size));
+}
+EXPORT_SYMBOL(dma_free_noncoherent);
+
+static void mips_dma_free_coherent(struct device *dev, size_t size, void *vaddr,
+ dma_addr_t dma_handle, struct dma_attrs *attrs)
+{
+ unsigned long addr = (unsigned long) vaddr;
+ int order = get_order(size);
+ unsigned int count = PAGE_ALIGN(size) >> PAGE_SHIFT;
+ struct page *page = NULL;
+
+ if (dma_release_from_coherent(dev, order, vaddr))
+ return;
+
+ plat_unmap_dma_mem(dev, dma_handle, size, DMA_BIDIRECTIONAL);
+
+ if (!plat_device_is_coherent(dev) && !hw_coherentio)
+ addr = CAC_ADDR(addr);
+
+ page = virt_to_page((void *) addr);
+
+ if (!dma_release_from_contiguous(dev, page, count))
+ __free_pages(page, get_order(size));
+}
+
+static inline void __dma_sync_virtual(void *addr, size_t size,
+ enum dma_data_direction direction)
+{
+ switch (direction) {
+ case DMA_TO_DEVICE:
+ dma_cache_wback((unsigned long)addr, size);
+ break;
+
+ case DMA_FROM_DEVICE:
+ dma_cache_inv((unsigned long)addr, size);
+ break;
+
+ case DMA_BIDIRECTIONAL:
+ dma_cache_wback_inv((unsigned long)addr, size);
+ break;
+
+ default:
+ BUG();
+ }
+}
+
+/*
+ * A single sg entry may refer to multiple physically contiguous
+ * pages. But we still need to process highmem pages individually.
+ * If highmem is not configured then the bulk of this loop gets
+ * optimized out.
+ */
+static inline void __dma_sync(struct page *page,
+ unsigned long offset, size_t size, enum dma_data_direction direction)
+{
+ size_t left = size;
+
+ do {
+ size_t len = left;
+
+ if (PageHighMem(page)) {
+ void *addr;
+
+ if (offset + len > PAGE_SIZE) {
+ if (offset >= PAGE_SIZE) {
+ page += offset >> PAGE_SHIFT;
+ offset &= ~PAGE_MASK;
+ }
+ len = PAGE_SIZE - offset;
+ }
+
+ addr = kmap_atomic(page);
+ __dma_sync_virtual(addr + offset, len, direction);
+ kunmap_atomic(addr);
+ } else
+ __dma_sync_virtual(page_address(page) + offset,
+ size, direction);
+ offset = 0;
+ page++;
+ left -= len;
+ } while (left);
+}
+
+static void mips_dma_unmap_page(struct device *dev, dma_addr_t dma_addr,
+ size_t size, enum dma_data_direction direction, struct dma_attrs *attrs)
+{
+ if (cpu_needs_post_dma_flush(dev))
+ __dma_sync(dma_addr_to_page(dev, dma_addr),
+ dma_addr & ~PAGE_MASK, size, direction);
+ plat_post_dma_flush(dev);
+ plat_unmap_dma_mem(dev, dma_addr, size, direction);
+}
+
+static int mips_dma_map_sg(struct device *dev, struct scatterlist *sg,
+ int nents, enum dma_data_direction direction, struct dma_attrs *attrs)
+{
+ int i;
+
+ for (i = 0; i < nents; i++, sg++) {
+ if (!plat_device_is_coherent(dev))
+ __dma_sync(sg_page(sg), sg->offset, sg->length,
+ direction);
+#ifdef CONFIG_NEED_SG_DMA_LENGTH
+ sg->dma_length = sg->length;
+#endif
+ sg->dma_address = plat_map_dma_mem_page(dev, sg_page(sg)) +
+ sg->offset;
+ }
+
+ return nents;
+}
+
+static dma_addr_t mips_dma_map_page(struct device *dev, struct page *page,
+ unsigned long offset, size_t size, enum dma_data_direction direction,
+ struct dma_attrs *attrs)
+{
+ if (!plat_device_is_coherent(dev))
+ __dma_sync(page, offset, size, direction);
+
+ return plat_map_dma_mem_page(dev, page) + offset;
+}
+
+static void mips_dma_unmap_sg(struct device *dev, struct scatterlist *sg,
+ int nhwentries, enum dma_data_direction direction,
+ struct dma_attrs *attrs)
+{
+ int i;
+
+ for (i = 0; i < nhwentries; i++, sg++) {
+ if (!plat_device_is_coherent(dev) &&
+ direction != DMA_TO_DEVICE)
+ __dma_sync(sg_page(sg), sg->offset, sg->length,
+ direction);
+ plat_unmap_dma_mem(dev, sg->dma_address, sg->length, direction);
+ }
+}
+
+static void mips_dma_sync_single_for_cpu(struct device *dev,
+ dma_addr_t dma_handle, size_t size, enum dma_data_direction direction)
+{
+ if (cpu_needs_post_dma_flush(dev))
+ __dma_sync(dma_addr_to_page(dev, dma_handle),
+ dma_handle & ~PAGE_MASK, size, direction);
+ plat_post_dma_flush(dev);
+}
+
+static void mips_dma_sync_single_for_device(struct device *dev,
+ dma_addr_t dma_handle, size_t size, enum dma_data_direction direction)
+{
+ if (!plat_device_is_coherent(dev))
+ __dma_sync(dma_addr_to_page(dev, dma_handle),
+ dma_handle & ~PAGE_MASK, size, direction);
+}
+
+static void mips_dma_sync_sg_for_cpu(struct device *dev,
+ struct scatterlist *sg, int nelems, enum dma_data_direction direction)
+{
+ int i;
+
+ if (cpu_needs_post_dma_flush(dev))
+ for (i = 0; i < nelems; i++, sg++)
+ __dma_sync(sg_page(sg), sg->offset, sg->length,
+ direction);
+ plat_post_dma_flush(dev);
+}
+
+static void mips_dma_sync_sg_for_device(struct device *dev,
+ struct scatterlist *sg, int nelems, enum dma_data_direction direction)
+{
+ int i;
+
+ if (!plat_device_is_coherent(dev))
+ for (i = 0; i < nelems; i++, sg++)
+ __dma_sync(sg_page(sg), sg->offset, sg->length,
+ direction);
+}
+
+int mips_dma_mapping_error(struct device *dev, dma_addr_t dma_addr)
+{
+ return 0;
+}
+
+int mips_dma_supported(struct device *dev, u64 mask)
+{
+ return plat_dma_supported(dev, mask);
+}
+
+void dma_cache_sync(struct device *dev, void *vaddr, size_t size,
+ enum dma_data_direction direction)
+{
+ BUG_ON(direction == DMA_NONE);
+
+ if (!plat_device_is_coherent(dev))
+ __dma_sync_virtual(vaddr, size, direction);
+}
+
+EXPORT_SYMBOL(dma_cache_sync);
+
+static struct dma_map_ops mips_default_dma_map_ops = {
+ .alloc = mips_dma_alloc_coherent,
+ .free = mips_dma_free_coherent,
+ .map_page = mips_dma_map_page,
+ .unmap_page = mips_dma_unmap_page,
+ .map_sg = mips_dma_map_sg,
+ .unmap_sg = mips_dma_unmap_sg,
+ .sync_single_for_cpu = mips_dma_sync_single_for_cpu,
+ .sync_single_for_device = mips_dma_sync_single_for_device,
+ .sync_sg_for_cpu = mips_dma_sync_sg_for_cpu,
+ .sync_sg_for_device = mips_dma_sync_sg_for_device,
+ .mapping_error = mips_dma_mapping_error,
+ .dma_supported = mips_dma_supported
+};
+
+struct dma_map_ops *mips_dma_map_ops = &mips_default_dma_map_ops;
+EXPORT_SYMBOL(mips_dma_map_ops);
+
+#define PREALLOC_DMA_DEBUG_ENTRIES (1 << 16)
+
+static int __init mips_dma_init(void)
+{
+ dma_debug_init(PREALLOC_DMA_DEBUG_ENTRIES);
+
+ return 0;
+}
+fs_initcall(mips_dma_init);