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Diffstat (limited to 'arch/mips/mm/dma-default.c')
-rw-r--r--arch/mips/mm/dma-default.c73
1 files changed, 49 insertions, 24 deletions
diff --git a/arch/mips/mm/dma-default.c b/arch/mips/mm/dma-default.c
index 46084912e58..44b6dff5aba 100644
--- a/arch/mips/mm/dma-default.c
+++ b/arch/mips/mm/dma-default.c
@@ -4,7 +4,7 @@
* for more details.
*
* Copyright (C) 2000 Ani Joshi <ajoshi@unixbox.com>
- * Copyright (C) 2000, 2001, 06 Ralf Baechle <ralf@linux-mips.org>
+ * Copyright (C) 2000, 2001, 06 Ralf Baechle <ralf@linux-mips.org>
* swiped from i386, and cloned for MIPS by Geert, polished by Ralf.
*/
@@ -18,10 +18,33 @@
#include <linux/highmem.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)
{
@@ -30,16 +53,20 @@ static inline struct page *dma_addr_to_page(struct device *dev,
}
/*
+ * 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.
*/
-
-static inline int cpu_is_noncoherent_r10000(struct device *dev)
+static inline int cpu_needs_post_dma_flush(struct device *dev)
{
return !plat_device_is_coherent(dev) &&
- (current_cpu_type() == CPU_R10000 ||
- current_cpu_type() == CPU_R12000);
+ (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)
@@ -98,7 +125,7 @@ void *dma_alloc_noncoherent(struct device *dev, size_t size,
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)
+ dma_addr_t * dma_handle, gfp_t gfp, struct dma_attrs *attrs)
{
void *ret;
@@ -115,7 +142,8 @@ static void *mips_dma_alloc_coherent(struct device *dev, size_t size,
if (!plat_device_is_coherent(dev)) {
dma_cache_wback_inv((unsigned long) ret, size);
- ret = UNCAC_ADDR(ret);
+ if (!hw_coherentio)
+ ret = UNCAC_ADDR(ret);
}
}
@@ -132,7 +160,7 @@ void dma_free_noncoherent(struct device *dev, size_t size, void *vaddr,
EXPORT_SYMBOL(dma_free_noncoherent);
static void mips_dma_free_coherent(struct device *dev, size_t size, void *vaddr,
- dma_addr_t dma_handle)
+ dma_addr_t dma_handle, struct dma_attrs *attrs)
{
unsigned long addr = (unsigned long) vaddr;
int order = get_order(size);
@@ -142,7 +170,7 @@ static void mips_dma_free_coherent(struct device *dev, size_t size, void *vaddr,
plat_unmap_dma_mem(dev, dma_handle, size, DMA_BIDIRECTIONAL);
- if (!plat_device_is_coherent(dev))
+ if (!plat_device_is_coherent(dev) && !hw_coherentio)
addr = CAC_ADDR(addr);
free_pages(addr, get_order(size));
@@ -209,7 +237,7 @@ static inline void __dma_sync(struct page *page,
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_is_noncoherent_r10000(dev))
+ if (cpu_needs_post_dma_flush(dev))
__dma_sync(dma_addr_to_page(dev, dma_addr),
dma_addr & ~PAGE_MASK, size, direction);
@@ -225,6 +253,9 @@ static int mips_dma_map_sg(struct device *dev, struct scatterlist *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;
}
@@ -260,7 +291,7 @@ static void mips_dma_unmap_sg(struct device *dev, struct scatterlist *sg,
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_is_noncoherent_r10000(dev))
+ if (cpu_needs_post_dma_flush(dev))
__dma_sync(dma_addr_to_page(dev, dma_handle),
dma_handle & ~PAGE_MASK, size, direction);
}
@@ -268,7 +299,6 @@ static void mips_dma_sync_single_for_cpu(struct device *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)
{
- plat_extra_sync_for_device(dev);
if (!plat_device_is_coherent(dev))
__dma_sync(dma_addr_to_page(dev, dma_handle),
dma_handle & ~PAGE_MASK, size, direction);
@@ -279,12 +309,10 @@ static void mips_dma_sync_sg_for_cpu(struct device *dev,
{
int i;
- /* Make sure that gcc doesn't leave the empty loop body. */
- for (i = 0; i < nelems; i++, sg++) {
- if (cpu_is_noncoherent_r10000(dev))
+ if (cpu_needs_post_dma_flush(dev))
+ for (i = 0; i < nelems; i++, sg++)
__dma_sync(sg_page(sg), sg->offset, sg->length,
direction);
- }
}
static void mips_dma_sync_sg_for_device(struct device *dev,
@@ -292,17 +320,15 @@ static void mips_dma_sync_sg_for_device(struct device *dev,
{
int i;
- /* Make sure that gcc doesn't leave the empty loop body. */
- for (i = 0; i < nelems; i++, sg++) {
- if (!plat_device_is_coherent(dev))
+ 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 plat_dma_mapping_error(dev, dma_addr);
+ return 0;
}
int mips_dma_supported(struct device *dev, u64 mask)
@@ -315,7 +341,6 @@ void dma_cache_sync(struct device *dev, void *vaddr, size_t size,
{
BUG_ON(direction == DMA_NONE);
- plat_extra_sync_for_device(dev);
if (!plat_device_is_coherent(dev))
__dma_sync_virtual(vaddr, size, direction);
}
@@ -323,8 +348,8 @@ void dma_cache_sync(struct device *dev, void *vaddr, size_t size,
EXPORT_SYMBOL(dma_cache_sync);
static struct dma_map_ops mips_default_dma_map_ops = {
- .alloc_coherent = mips_dma_alloc_coherent,
- .free_coherent = mips_dma_free_coherent,
+ .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,
generated by cgit v1.2.3-70-g09d2 (git 2.46.0) at 2025-11-09 17:36:17 +0000