Hi Marek,
On Wed, 29 Feb 2012 16:04:22 +0100
Marek Szyprowski <m.szyprowski@xxxxxxxxxxx> wrote:
> This patch add a complete implementation of DMA-mapping API for
> devices that have IOMMU support. All DMA-mapping calls are supported.
>
> This patch contains some of the code kindly provided by Krishna Reddy
> <vdumpa@xxxxxxxxxx> and Andrzej Pietrasiewicz <andrzej.p@xxxxxxxxxxx>
>
> Signed-off-by: Marek Szyprowski <m.szyprowski@xxxxxxxxxxx>
> Signed-off-by: Kyungmin Park <kyungmin.park@xxxxxxxxxxx>
> Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@xxxxxxxxxx>
> ---
> arch/arm/Kconfig | 8 +
> arch/arm/include/asm/device.h | 3 +
> arch/arm/include/asm/dma-iommu.h | 34 ++
> arch/arm/mm/dma-mapping.c | 726 +++++++++++++++++++++++++++++++++++++-
> arch/arm/mm/vmregion.h | 2 +-
> 5 files changed, 758 insertions(+), 15 deletions(-)
> create mode 100644 arch/arm/include/asm/dma-iommu.h
>
<snip>
> +/*
> + * Map a part of the scatter-gather list into contiguous io address space
> + */
> +static int __map_sg_chunk(struct device *dev, struct scatterlist *sg,
> + size_t size, dma_addr_t *handle,
> + enum dma_data_direction dir)
> +{
> + struct dma_iommu_mapping *mapping = dev->archdata.mapping;
> + dma_addr_t iova, iova_base;
> + int ret = 0;
> + unsigned int count;
> + struct scatterlist *s;
> +
> + size = PAGE_ALIGN(size);
> + *handle = ARM_DMA_ERROR;
> +
> + iova_base = iova = __alloc_iova(mapping, size);
> + if (iova == ARM_DMA_ERROR)
> + return -ENOMEM;
> +
> + for (count = 0, s = sg; count < (size >> PAGE_SHIFT); s = sg_next(s))
> + {
> + phys_addr_t phys = page_to_phys(sg_page(s));
> + unsigned int len = PAGE_ALIGN(s->offset + s->length);
> +
> + if (!arch_is_coherent())
> + __dma_page_cpu_to_dev(sg_page(s), s->offset, s->length, dir);
> +
> + ret = iommu_map(mapping->domain, iova, phys, len, 0);
> + if (ret < 0)
> + goto fail;
> + count += len >> PAGE_SHIFT;
> + iova += len;
> + }
> + *handle = iova_base;
> +
> + return 0;
> +fail:
> + iommu_unmap(mapping->domain, iova_base, count * PAGE_SIZE);
> + __free_iova(mapping, iova_base, size);
> + return ret;
> +}
Do we need to set dma_address as below?
>From e8bcc3cdac5375b5d7f5ac5b3f716a11c1008f38 Mon Sep 17 00:00:00 2001
From: Hiroshi DOYU <hdoyu@xxxxxxxxxx>
Date: Thu, 29 Mar 2012 09:59:04 +0300
Subject: [PATCH 1/1] ARM: dma-mapping: Fix dma_address in sglist
s->dma_address wasn't set at mapping.
Signed-off-by: Hiroshi DOYU <hdoyu@xxxxxxxxxx>
---
arch/arm/mm/dma-mapping.c | 2 ++
1 files changed, 2 insertions(+), 0 deletions(-)
diff --git a/arch/arm/mm/dma-mapping.c b/arch/arm/mm/dma-mapping.c
index 3347c37..11a9d65 100644
--- a/arch/arm/mm/dma-mapping.c
+++ b/arch/arm/mm/dma-mapping.c
@@ -1111,6 +1111,8 @@ static int __map_sg_chunk(struct device *dev, struct scatterlist *sg,
ret = iommu_map(mapping->domain, iova, phys, len, 0);
if (ret < 0)
goto fail;
+ s->dma_address = iova;
+
count += len >> PAGE_SHIFT;
iova += len;
}
--
1.7.5.4
--
To unsubscribe, send a message with 'unsubscribe linux-mm' in
the body to majordomo@xxxxxxxxx. For more info on Linux MM,
see: http://www.linux-mm.org/ .
Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/
Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>