[RFC PATCH 5/7] dma-mapping: detect and configure IOMMU in of_dma_configure
From: Will Deacon <hidden>
Date: 2014-08-29 15:54:28
Also in:
linux-iommu
Subsystem:
arm port, dma mapping helpers, open firmware and flattened device tree, the rest · Maintainers:
Russell King, Marek Szyprowski, Rob Herring, Saravana Kannan, Linus Torvalds
This patch extends of_dma_configure so that it sets up the IOMMU for a device, as well as the coherent/non-coherent DMA mapping ops. Signed-off-by: Will Deacon <redacted> --- arch/arm/include/asm/dma-mapping.h | 4 +++- drivers/of/platform.c | 37 ++++++++++++++++++++++--------------- include/linux/dma-mapping.h | 4 +++- 3 files changed, 28 insertions(+), 17 deletions(-)
diff --git a/arch/arm/include/asm/dma-mapping.h b/arch/arm/include/asm/dma-mapping.h
index 936125ef3f3f..48adace87d6d 100644
--- a/arch/arm/include/asm/dma-mapping.h
+++ b/arch/arm/include/asm/dma-mapping.h@@ -122,7 +122,9 @@ static inline unsigned long dma_max_pfn(struct device *dev) #define dma_max_pfn(dev) dma_max_pfn(dev) static inline void arch_setup_dma_ops(struct device *dev, u64 mask, - unsigned long offset, bool coherent) + u64 dma_base, u64 size, + unsigned long offset, bool coherent, + bool iommu) { dev->coherent_dma_mask = mask;
diff --git a/drivers/of/platform.c b/drivers/of/platform.c
index 484c558c63a6..826beffdc50d 100644
--- a/drivers/of/platform.c
+++ b/drivers/of/platform.c@@ -19,6 +19,7 @@ #include <linux/slab.h> #include <linux/of_address.h> #include <linux/of_device.h> +#include <linux/of_iommu.h> #include <linux/of_irq.h> #include <linux/of_platform.h> #include <linux/platform_device.h>
@@ -162,25 +163,36 @@ EXPORT_SYMBOL(of_device_alloc); */ static void of_dma_configure(struct platform_device *pdev) { - u64 dma_addr, paddr, size; + u64 dma_addr, paddr, size, mask; int ret; - bool coherent; + bool coherent, iommu; unsigned long offset; struct device *dev = &pdev->dev; + /* + * Set default dma-mask to 32 bit. Drivers are expected to setup + * the correct supported dma_mask. + */ + mask = DMA_BIT_MASK(32); + ret = of_dma_get_range(dev->of_node, &dma_addr, &paddr, &size); - offset = ret < 0 ? 0 : PFN_DOWN(paddr - dma_addr); - dev_dbg(dev, "dma_pfn_offset(%#08lx)\n", dev->dma_pfn_offset); + if (ret < 0) { + dma_addr = offset = 0; + size = mask; + } else { + offset = PFN_DOWN(paddr - dma_addr); + dev_dbg(dev, "dma_pfn_offset(%#08lx)\n", dev->dma_pfn_offset); + } coherent = of_dma_is_coherent(dev->of_node); dev_dbg(dev, "device is%sdma coherent\n", coherent ? " " : " not "); - /* - * Set default dma-mask to 32 bit. Drivers are expected to setup - * the correct supported dma_mask. - */ - arch_setup_dma_ops(dev, DMA_BIT_MASK(32), offset, coherent); + iommu = !of_iommu_configure(dev); + dev_dbg(dev, "device is%sbehind an iommu\n", + iommu ? " " : " not "); + + arch_setup_dma_ops(dev, mask, dma_addr, size, offset, coherent, iommu); } /**
@@ -209,14 +221,9 @@ static struct platform_device *of_platform_device_create_pdata( if (!dev) goto err_clear_flag; - of_dma_configure(dev); dev->dev.bus = &platform_bus_type; dev->dev.platform_data = platform_data; - - /* We do not fill the DMA ops for platform devices by default. - * This is currently the responsibility of the platform code - * to do such, possibly using a device notifier - */ + of_dma_configure(dev); if (of_device_add(dev) != 0) { platform_device_put(dev);
diff --git a/include/linux/dma-mapping.h b/include/linux/dma-mapping.h
index 0f7f7b68b0db..348ab66c7e0c 100644
--- a/include/linux/dma-mapping.h
+++ b/include/linux/dma-mapping.h@@ -131,7 +131,9 @@ extern u64 dma_get_required_mask(struct device *dev); #ifndef arch_setup_dma_ops static inline void arch_setup_dma_ops(struct device *dev, u64 mask, - unsigned long offset, bool coherent) { } + u64 dma_base, u64 size, + unsigned long offset, bool coherent, + bool iommu) { } #endif static inline unsigned int dma_get_max_seg_size(struct device *dev)
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2.1.0