ACPI/IORT: Make dma masks set-up IORT specific (18b709be) · Commits · 戴 / test

The introduction of acpi_dma_configure() allows to configure DMA and related IOMMU for any device that is DMA capable. To achieve that goal it ensures DMA masks are set-up to sane default values before proceeding with IOMMU and DMA ops configuration. On x86/ia64 systems, through acpi_bind_one(), acpi_dma_configure() is called for every device that has an ACPI companion, in that every device is considered DMA capable on x86/ia64 systems (ie acpi_get_dma_attr() API), which has the side effect of initializing dma masks also for pseudo-devices (eg CPUs and memory nodes) and potentially for devices whose dma masks were not set-up before the acpi_dma_configure() API was introduced, which may have noxious side effects. Therefore, in preparation for IORT firmware specific DMA masks set-up, wrap the default DMA masks set-up in acpi_dma_configure() inside an IORT specific wrapper that reverts to a NOP on x86/ia64 systems, restoring the default expected behaviour on x86/ia64 systems and keeping DMA default masks set-up on IORT based (ie ARM) arch configurations. Signed-off-by:

Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> Acked-by:

Will Deacon <will.deacon@arm.com> Acked-by:

Rafael J. Wysocki <rafael.j.wysocki@intel.com> Reviewed-by:

Hanjun Guo <hanjun.guo@linaro.org> Tested-by:

Hanjun Guo <hanjun.guo@linaro.org> Cc: Will Deacon <will.deacon@arm.com> Cc: Hanjun Guo <hanjun.guo@linaro.org> Cc: Bjorn Helgaas <bhelgaas@google.com> Cc: Robin Murphy <robin.murphy@arm.com> Cc: Tomasz Nowicki <tn@semihalf.com> Cc: Joerg Roedel <joro@8bytes.org> Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net> Cc: Sricharan R <sricharan@codeaurora.org> Signed-off-by:

Joerg Roedel <jroedel@suse.de>

drivers/acpi/arm64/iort.c

+22 −0

Original line number	Diff line number	Diff line
		@@ -546,6 +546,28 @@ static const struct iommu_ops iort_iommu_xlate(struct device dev,
		return ret ? NULL : ops;
		}

		/**
		* iort_set_dma_mask - Set-up dma mask for a device.
		*
		* @dev: device to configure
		*/
		void iort_set_dma_mask(struct device *dev)
		{
		/*
		* 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;
		}

		/**
		* iort_iommu_configure - Set-up IOMMU configuration for a device.
		*

drivers/acpi/scan.c

+1 −13

Original line number	Diff line number	Diff line
		@@ -1380,19 +1380,7 @@ void acpi_dma_configure(struct device *dev, enum dev_dma_attr attr)
		{
		const struct iommu_ops *iommu;

		/*
		* 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;
		iort_set_dma_mask(dev);

		iommu = iort_iommu_configure(dev);

include/linux/acpi_iort.h

+2 −0

Original line number	Diff line number	Diff line
		@@ -35,6 +35,7 @@ bool iort_node_match(u8 type);
		u32 iort_msi_map_rid(struct device *dev, u32 req_id);
		struct irq_domain iort_get_device_domain(struct device dev, u32 req_id);
		/* IOMMU interface */
		void iort_set_dma_mask(struct device *dev);
		const struct iommu_ops iort_iommu_configure(struct device dev);
		#else
		static inline void acpi_iort_init(void) { }
		@@ -45,6 +46,7 @@ static inline struct irq_domain iort_get_device_domain(struct device dev,
		u32 req_id)
		{ return NULL; }
		/* IOMMU interface */
		static inline void iort_set_dma_mask(struct device *dev) { }
		static inline
		const struct iommu_ops iort_iommu_configure(struct device dev)
		{ return NULL; }

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