diff options
Diffstat (limited to 'arm-of-restrict-dma-configuration.patch')
| -rw-r--r-- | arm-of-restrict-dma-configuration.patch | 121 |
1 files changed, 0 insertions, 121 deletions
diff --git a/arm-of-restrict-dma-configuration.patch b/arm-of-restrict-dma-configuration.patch deleted file mode 100644 index cc9ddd965..000000000 --- a/arm-of-restrict-dma-configuration.patch +++ /dev/null @@ -1,121 +0,0 @@ -From 723288836628bc1c0855f3bb7b64b1803e4b9e4a Mon Sep 17 00:00:00 2001 -From: Robin Murphy <robin.murphy@arm.com> -Date: Thu, 31 Aug 2017 11:32:54 +0100 -Subject: of: restrict DMA configuration - -Moving DMA configuration to happen later at driver probe time had the -unnoticed side-effect that we now perform DMA configuration for *every* -device represented in DT, rather than only those explicitly created by -the of_platform and PCI code. - -As Christoph points out, this is not really the best thing to do. Whilst -there may well be other DMA-capable buses that can benefit from having -their children automatically configured after the bridge has probed, -there are also plenty of others like USB, MDIO, etc. that definitely do -not support DMA and should not be indiscriminately processed. - -The good news is that in most cases the DT "dma-ranges" property serves -as an appropriate indicator - per a strict interpretation of the spec, -anything lacking a "dma-ranges" property should be considered not to -have a mapping of DMA address space from its children to its parent, -thus anything for which of_dma_get_range() does not succeed does not -need DMA configuration. Certain bus types have a general expectation of -DMA capability and carry a well-established precedent that an absent -"dma-ranges" implies the same as the empty property, so we automatically -opt those in to DMA configuration regardless, to avoid regressing most -existing platforms. - -Fixes: 09515ef5ddad ("of/acpi: Configure dma operations at probe time for platform/amba/pci bus devices") -Reported-by: Christoph Hellwig <hch@lst.de> -Signed-off-by: Robin Murphy <robin.murphy@arm.com> -Acked-by: Rob Herring <robh@kernel.org> -Signed-off-by: Christoph Hellwig <hch@lst.de> ---- - drivers/of/device.c | 48 ++++++++++++++++++++++++++++++++---------------- - 1 file changed, 32 insertions(+), 16 deletions(-) - -diff --git a/drivers/of/device.c b/drivers/of/device.c -index e0a28ea..04c4c95 100644 ---- a/drivers/of/device.c -+++ b/drivers/of/device.c -@@ -9,6 +9,9 @@ - #include <linux/module.h> - #include <linux/mod_devicetable.h> - #include <linux/slab.h> -+#include <linux/pci.h> -+#include <linux/platform_device.h> -+#include <linux/amba/bus.h> - - #include <asm/errno.h> - #include "of_private.h" -@@ -84,31 +87,28 @@ int of_device_add(struct platform_device *ofdev) - */ - int of_dma_configure(struct device *dev, struct device_node *np) - { -- u64 dma_addr, paddr, size; -+ u64 dma_addr, paddr, size = 0; - int ret; - bool coherent; - unsigned long offset; - const struct iommu_ops *iommu; - u64 mask; - -- /* -- * Set default coherent_dma_mask to 32 bit. Drivers are expected to -- * setup the correct supported mask. -- */ -- if (!dev->coherent_dma_mask) -- dev->coherent_dma_mask = DMA_BIT_MASK(32); -- -- /* -- * Set it to coherent_dma_mask by default if the architecture -- * code has not set it. -- */ -- if (!dev->dma_mask) -- dev->dma_mask = &dev->coherent_dma_mask; -- - ret = of_dma_get_range(np, &dma_addr, &paddr, &size); - if (ret < 0) { -+ /* -+ * For legacy reasons, we have to assume some devices need -+ * DMA configuration regardless of whether "dma-ranges" is -+ * correctly specified or not. -+ */ -+ if (!dev_is_pci(dev) && -+#ifdef CONFIG_ARM_AMBA -+ dev->bus != &amba_bustype && -+#endif -+ dev->bus != &platform_bus_type) -+ return ret == -ENODEV ? 0 : ret; -+ - dma_addr = offset = 0; -- size = max(dev->coherent_dma_mask, dev->coherent_dma_mask + 1); - } else { - offset = PFN_DOWN(paddr - dma_addr); - -@@ -129,6 +129,22 @@ int of_dma_configure(struct device *dev, struct device_node *np) - dev_dbg(dev, "dma_pfn_offset(%#08lx)\n", offset); - } - -+ /* -+ * Set default coherent_dma_mask to 32 bit. Drivers are expected to -+ * setup the correct supported mask. -+ */ -+ if (!dev->coherent_dma_mask) -+ dev->coherent_dma_mask = DMA_BIT_MASK(32); -+ /* -+ * Set it to coherent_dma_mask by default if the architecture -+ * code has not set it. -+ */ -+ if (!dev->dma_mask) -+ dev->dma_mask = &dev->coherent_dma_mask; -+ -+ if (!size) -+ size = max(dev->coherent_dma_mask, dev->coherent_dma_mask + 1); -+ - dev->dma_pfn_offset = offset; - - /* --- -cgit v1.1 - |