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author | Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> | 2017-08-07 11:29:49 +0100 |
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committer | Rafael J. Wysocki <rafael.j.wysocki@intel.com> | 2017-08-07 14:28:51 +0200 |
commit | 7ad4263980826e8b02e121af22f4f4c9103fe86d (patch) | |
tree | 436c849f4eb9c25377579743121d8b956ae2e57d /drivers/acpi/arm64 | |
parent | c04ac679c6b86e4e36fbb675c6c061b4091f5810 (diff) | |
download | linux-7ad4263980826e8b02e121af22f4f4c9103fe86d.tar.gz linux-7ad4263980826e8b02e121af22f4f4c9103fe86d.tar.bz2 linux-7ad4263980826e8b02e121af22f4f4c9103fe86d.zip |
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 <lorenzo.pieralisi@arm.com>
Acked-by: Will Deacon <will.deacon@arm.com>
Tested-by: Nate Watterson <nwatters@codeaurora.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Diffstat (limited to 'drivers/acpi/arm64')
-rw-r--r-- | drivers/acpi/arm64/iort.c | 37 |
1 files changed, 35 insertions, 2 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); } /** |