From 7ad4263980826e8b02e121af22f4f4c9103fe86d Mon Sep 17 00:00:00 2001 From: Lorenzo Pieralisi Date: Mon, 7 Aug 2017 11:29:49 +0100 Subject: [PATCH] ACPI: Make acpi_dma_configure() DMA regions aware Current ACPI DMA configuration set-up device DMA capabilities through kernel defaults that do not take into account platform specific DMA configurations reported by firmware. By leveraging the ACPI acpi_dev_get_dma_resources() API, add code in acpi_dma_configure() to retrieve the DMA regions to correctly set-up PCI devices DMA parameters. Rework the ACPI IORT kernel API to make sure they can accommodate the DMA set-up required by firmware. By making PCI devices DMA set-up ACPI IORT specific, the kernel is shielded from unwanted regressions that could be triggered by parsing DMA resources on arches that were previously ignoring them (ie x86/ia64), leaving kernel behaviour unchanged on those arches. Signed-off-by: Lorenzo Pieralisi Acked-by: Will Deacon Tested-by: Nate Watterson Signed-off-by: Rafael J. Wysocki --- drivers/acpi/arm64/iort.c | 37 +++++++++++++++++++++++++++++++++++-- drivers/acpi/scan.c | 12 ++++-------- include/linux/acpi_iort.h | 5 +++-- 3 files changed, 42 insertions(+), 12 deletions(-) diff --git a/drivers/acpi/arm64/iort.c b/drivers/acpi/arm64/iort.c index a3215ee671c1..606af87c425f 100644 --- a/drivers/acpi/arm64/iort.c +++ b/drivers/acpi/arm64/iort.c @@ -681,12 +681,17 @@ static const struct iommu_ops *iort_iommu_xlate(struct device *dev, } /** - * iort_set_dma_mask - Set-up dma mask for a device. + * iort_dma_setup() - Set-up device DMA parameters. * * @dev: device to configure + * @dma_addr: device DMA address result pointer + * @size: DMA range size result pointer */ -void iort_set_dma_mask(struct device *dev) +void iort_dma_setup(struct device *dev, u64 *dma_addr, u64 *dma_size) { + u64 mask, dmaaddr = 0, size = 0, offset = 0; + int ret, msb; + /* * Set default coherent_dma_mask to 32 bit. Drivers are expected to * setup the correct supported mask. @@ -700,6 +705,34 @@ void iort_set_dma_mask(struct device *dev) */ if (!dev->dma_mask) dev->dma_mask = &dev->coherent_dma_mask; + + size = max(dev->coherent_dma_mask, dev->coherent_dma_mask + 1); + + if (dev_is_pci(dev)) { + ret = acpi_dma_get_range(dev, &dmaaddr, &offset, &size); + if (!ret) { + msb = fls64(dmaaddr + size - 1); + /* + * Round-up to the power-of-two mask or set + * the mask to the whole 64-bit address space + * in case the DMA region covers the full + * memory window. + */ + mask = msb == 64 ? U64_MAX : (1ULL << msb) - 1; + /* + * Limit coherent and dma mask based on size + * retrieved from firmware. + */ + dev->coherent_dma_mask = mask; + *dev->dma_mask = mask; + } + } + + *dma_addr = dmaaddr; + *dma_size = size; + + dev->dma_pfn_offset = PFN_DOWN(offset); + dev_dbg(dev, "dma_pfn_offset(%#08llx)\n", offset); } /** diff --git a/drivers/acpi/scan.c b/drivers/acpi/scan.c index 94500d99f2d6..0483d36433ac 100644 --- a/drivers/acpi/scan.c +++ b/drivers/acpi/scan.c @@ -1446,20 +1446,16 @@ int acpi_dma_get_range(struct device *dev, u64 *dma_addr, u64 *offset, int acpi_dma_configure(struct device *dev, enum dev_dma_attr attr) { const struct iommu_ops *iommu; - u64 size; + u64 dma_addr = 0, size = 0; - iort_set_dma_mask(dev); + iort_dma_setup(dev, &dma_addr, &size); iommu = iort_iommu_configure(dev); if (IS_ERR(iommu) && PTR_ERR(iommu) == -EPROBE_DEFER) return -EPROBE_DEFER; - size = max(dev->coherent_dma_mask, dev->coherent_dma_mask + 1); - /* - * Assume dma valid range starts at 0 and covers the whole - * coherent_dma_mask. - */ - arch_setup_dma_ops(dev, 0, size, iommu, attr == DEV_DMA_COHERENT); + arch_setup_dma_ops(dev, dma_addr, size, + iommu, attr == DEV_DMA_COHERENT); return 0; } diff --git a/include/linux/acpi_iort.h b/include/linux/acpi_iort.h index 8379d406ad2e..8d3f0bf80379 100644 --- a/include/linux/acpi_iort.h +++ b/include/linux/acpi_iort.h @@ -36,7 +36,7 @@ struct irq_domain *iort_get_device_domain(struct device *dev, u32 req_id); void acpi_configure_pmsi_domain(struct device *dev); int iort_pmsi_get_dev_id(struct device *dev, u32 *dev_id); /* IOMMU interface */ -void iort_set_dma_mask(struct device *dev); +void iort_dma_setup(struct device *dev, u64 *dma_addr, u64 *size); const struct iommu_ops *iort_iommu_configure(struct device *dev); #else static inline void acpi_iort_init(void) { } @@ -47,7 +47,8 @@ static inline struct irq_domain *iort_get_device_domain(struct device *dev, { return NULL; } static inline void acpi_configure_pmsi_domain(struct device *dev) { } /* IOMMU interface */ -static inline void iort_set_dma_mask(struct device *dev) { } +static inline void iort_dma_setup(struct device *dev, u64 *dma_addr, + u64 *size) { } static inline const struct iommu_ops *iort_iommu_configure(struct device *dev) { return NULL; }