diff options
Diffstat (limited to 'meta-rcar-gen3-adas/recipes-kernel/linux/linux-renesas/0008-arm64-do-not-set-dma-masks-that-device-connection-ca.patch')
| -rw-r--r-- | meta-rcar-gen3-adas/recipes-kernel/linux/linux-renesas/0008-arm64-do-not-set-dma-masks-that-device-connection-ca.patch | 132 |
1 files changed, 132 insertions, 0 deletions
diff --git a/meta-rcar-gen3-adas/recipes-kernel/linux/linux-renesas/0008-arm64-do-not-set-dma-masks-that-device-connection-ca.patch b/meta-rcar-gen3-adas/recipes-kernel/linux/linux-renesas/0008-arm64-do-not-set-dma-masks-that-device-connection-ca.patch new file mode 100644 index 0000000..14612cd --- /dev/null +++ b/meta-rcar-gen3-adas/recipes-kernel/linux/linux-renesas/0008-arm64-do-not-set-dma-masks-that-device-connection-ca.patch @@ -0,0 +1,132 @@ +From e3218ab51b0bf3f193a9f64e5c0dafe74e292ad2 Mon Sep 17 00:00:00 2001 +From: Nikita Yushchenko <nikita.yoush@cogentembedded.com> +Date: Fri, 6 Jan 2017 17:12:49 +0300 +Subject: [PATCH] arm64: do not set dma masks that device connection can't + handle + +It is possible that device is capable of 64-bit DMA addresses, and +device driver tries to set wide DMA mask, but bridge or bus used to +connect device to the system can't handle wide addresses. + +With swiotlb, memory above 4G still can be used by drivers for streaming +DMA, but *dev->mask and dev->dma_coherent_mask must still keep values +that hardware handles physically. + +This patch enforces that. Based on original version by +Arnd Bergmann <arnd@arndb.de>, extended with coherent mask hadnling. + +Signed-off-by: Nikita Yushchenko <nikita.yoush@cogentembedded.com> +CC: Arnd Bergmann <arnd@arndb.de> +--- + arch/arm64/Kconfig | 3 +++ + arch/arm64/include/asm/device.h | 1 + + arch/arm64/mm/dma-mapping.c | 51 +++++++++++++++++++++++++++++++++++++++++ + 3 files changed, 55 insertions(+) + +diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig +index 76747d92bc72..9513d2eb5c8a 100644 +--- a/arch/arm64/Kconfig ++++ b/arch/arm64/Kconfig +@@ -191,6 +191,9 @@ config NEED_DMA_MAP_STATE + config NEED_SG_DMA_LENGTH + def_bool y + ++config ARCH_HAS_DMA_SET_COHERENT_MASK ++ def_bool y ++ + config SMP + def_bool y + +diff --git a/arch/arm64/include/asm/device.h b/arch/arm64/include/asm/device.h +index 243ef256b8c9..a57e7bb10e71 100644 +--- a/arch/arm64/include/asm/device.h ++++ b/arch/arm64/include/asm/device.h +@@ -22,6 +22,7 @@ struct dev_archdata { + void *iommu; /* private IOMMU data */ + #endif + bool dma_coherent; ++ u64 parent_dma_mask; + }; + + struct pdev_archdata { +diff --git a/arch/arm64/mm/dma-mapping.c b/arch/arm64/mm/dma-mapping.c +index 46a4157adc17..04b9bce96f1b 100644 +--- a/arch/arm64/mm/dma-mapping.c ++++ b/arch/arm64/mm/dma-mapping.c +@@ -351,6 +351,30 @@ static int __swiotlb_dma_supported(struct device *hwdev, u64 mask) + return 1; + } + ++static int __swiotlb_set_dma_mask(struct device *dev, u64 mask) ++{ ++ /* device is not DMA capable */ ++ if (!dev->dma_mask) ++ return -EIO; ++ ++ /* mask is below swiotlb bounce buffer, so fail */ ++ if (!swiotlb_dma_supported(dev, mask)) ++ return -EIO; ++ ++ /* ++ * because of the swiotlb, we can return success for ++ * larger masks, but need to ensure that bounce buffers ++ * are used above parent_dma_mask, so set that as ++ * the effective mask. ++ */ ++ if (mask > dev->archdata.parent_dma_mask) ++ mask = dev->archdata.parent_dma_mask; ++ ++ *dev->dma_mask = mask; ++ ++ return 0; ++} ++ + static struct dma_map_ops swiotlb_dma_ops = { + .alloc = __dma_alloc, + .free = __dma_free, +@@ -366,8 +390,23 @@ static struct dma_map_ops swiotlb_dma_ops = { + .sync_sg_for_device = __swiotlb_sync_sg_for_device, + .dma_supported = __swiotlb_dma_supported, + .mapping_error = swiotlb_dma_mapping_error, ++ .set_dma_mask = __swiotlb_set_dma_mask, + }; + ++int dma_set_coherent_mask(struct device *dev, u64 mask) ++{ ++ if (!dma_supported(dev, mask)) ++ return -EIO; ++ ++ if (get_dma_ops(dev) == &swiotlb_dma_ops && ++ mask > dev->archdata.parent_dma_mask) ++ mask = dev->archdata.parent_dma_mask; ++ ++ dev->coherent_dma_mask = mask; ++ return 0; ++} ++EXPORT_SYMBOL(dma_set_coherent_mask); ++ + static int __init atomic_pool_init(void) + { + pgprot_t prot = __pgprot(PROT_NORMAL_NC); +@@ -971,6 +1010,18 @@ void arch_setup_dma_ops(struct device *dev, u64 dma_base, u64 size, + if (!dev->archdata.dma_ops) + dev->archdata.dma_ops = &swiotlb_dma_ops; + ++ /* ++ * we don't yet support buses that have a non-zero mapping. ++ * Let's hope we won't need it ++ */ ++ WARN_ON(dma_base != 0); ++ ++ /* ++ * Whatever the parent bus can set. A device must not set ++ * a DMA mask larger than this. ++ */ ++ dev->archdata.parent_dma_mask = size - 1; ++ + dev->archdata.dma_coherent = coherent; + __iommu_setup_dma_ops(dev, dma_base, size, iommu); + } +-- +2.11.0 + |