| Message ID | a85c534af867534e6693ce50a746fda096426586.1452010803.git.brian.starkey@arm.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Tue, Jan 05 2016, Brian Starkey wrote: > When the DMA_MEMORY_MAP flag is used, memory which can be accessed > directly should be returned, so use memremap(..., MEMREMAP_WC) to > provide a writecombine mapping. > > Signed-off-by: Brian Starkey <brian.starkey@arm.com> > Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Acked-by: Michal Nazarewicz <mina86@mina86.com> > --- > drivers/base/dma-coherent.c | 20 ++++++++++++++++---- > 1 file changed, 16 insertions(+), 4 deletions(-) > > diff --git a/drivers/base/dma-coherent.c b/drivers/base/dma-coherent.c > index 55b8398..f98359a 100644 > --- a/drivers/base/dma-coherent.c > +++ b/drivers/base/dma-coherent.c > @@ -2,6 +2,7 @@ > * Coherent per-device memory handling. > * Borrowed from i386 > */ > +#include <linux/io.h> > #include <linux/slab.h> > #include <linux/kernel.h> > #include <linux/module.h> > @@ -31,7 +32,10 @@ static int dma_init_coherent_memory(phys_addr_t phys_addr, dma_addr_t device_add > if (!size) > goto out; > > - mem_base = ioremap(phys_addr, size); > + if (flags & DMA_MEMORY_MAP) > + mem_base = memremap(phys_addr, size, MEMREMAP_WC); > + else > + mem_base = ioremap(phys_addr, size); > if (!mem_base) > goto out; > > @@ -58,8 +62,12 @@ static int dma_init_coherent_memory(phys_addr_t phys_addr, dma_addr_t device_add > > out: > kfree(dma_mem); > - if (mem_base) > - iounmap(mem_base); > + if (mem_base) { > + if (flags & DMA_MEMORY_MAP) > + memunmap(mem_base); > + else > + iounmap(mem_base); > + } > return 0; > } > > @@ -67,7 +75,11 @@ static void dma_release_coherent_memory(struct dma_coherent_mem *mem) > { > if (!mem) > return; > - iounmap(mem->virt_base); > + > + if (mem->flags & DMA_MEMORY_MAP) > + memunmap(mem->virt_base); > + else > + iounmap(mem->virt_base); > kfree(mem->bitmap); > kfree(mem); > } > -- > 1.7.9.5 >
diff --git a/drivers/base/dma-coherent.c b/drivers/base/dma-coherent.c index 55b8398..f98359a 100644 --- a/drivers/base/dma-coherent.c +++ b/drivers/base/dma-coherent.c @@ -2,6 +2,7 @@ * Coherent per-device memory handling. * Borrowed from i386 */ +#include <linux/io.h> #include <linux/slab.h> #include <linux/kernel.h> #include <linux/module.h> @@ -31,7 +32,10 @@ static int dma_init_coherent_memory(phys_addr_t phys_addr, dma_addr_t device_add if (!size) goto out; - mem_base = ioremap(phys_addr, size); + if (flags & DMA_MEMORY_MAP) + mem_base = memremap(phys_addr, size, MEMREMAP_WC); + else + mem_base = ioremap(phys_addr, size); if (!mem_base) goto out; @@ -58,8 +62,12 @@ static int dma_init_coherent_memory(phys_addr_t phys_addr, dma_addr_t device_add out: kfree(dma_mem); - if (mem_base) - iounmap(mem_base); + if (mem_base) { + if (flags & DMA_MEMORY_MAP) + memunmap(mem_base); + else + iounmap(mem_base); + } return 0; } @@ -67,7 +75,11 @@ static void dma_release_coherent_memory(struct dma_coherent_mem *mem) { if (!mem) return; - iounmap(mem->virt_base); + + if (mem->flags & DMA_MEMORY_MAP) + memunmap(mem->virt_base); + else + iounmap(mem->virt_base); kfree(mem->bitmap); kfree(mem); }