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authorLorenzo Pieralisi <lorenzo.pieralisi@arm.com>2017-08-07 13:29:49 +0300
committerRafael J. Wysocki <rafael.j.wysocki@intel.com>2017-08-07 15:28:51 +0300
commit7ad4263980826e8b02e121af22f4f4c9103fe86d (patch)
tree436c849f4eb9c25377579743121d8b956ae2e57d /drivers/acpi/arm64
parentc04ac679c6b86e4e36fbb675c6c061b4091f5810 (diff)
downloadlinux-7ad4263980826e8b02e121af22f4f4c9103fe86d.tar.xz
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.c37
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);
}
/**