ACPI/IORT: Add IORT named component memory address limits

IORT named components provide firmware configuration describing
how many address bits a given device is capable of generating
to address memory.

Add code to the kernel to retrieve memory address limits
configuration for IORT named components and configure DMA masks
accordingly.

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>

diff --git a/drivers/acpi/arm64/iort.c b/drivers/acpi/arm64/iort.c
index 606af87c425fb6521aa15f30daf6215a94873e96..5b9e8dc29c090781ccfc1dd3e1c71c5bf1a4bd03 100644 (file)
--- a/drivers/acpi/arm64/iort.c
+++ b/drivers/acpi/arm64/iort.c
@@ -680,6 +680,24 @@ static const struct iommu_ops *iort_iommu_xlate(struct device *dev,
        return ret ? NULL : ops;
 }
 
+static int nc_dma_get_range(struct device *dev, u64 *size)
+{
+       struct acpi_iort_node *node;
+       struct acpi_iort_named_component *ncomp;
+
+       node = iort_scan_node(ACPI_IORT_NODE_NAMED_COMPONENT,
+                             iort_match_node_callback, dev);
+       if (!node)
+               return -ENODEV;
+
+       ncomp = (struct acpi_iort_named_component *)node->node_data;
+
+       *size = ncomp->memory_address_limit >= 64 ? U64_MAX :
+                       1ULL<<ncomp->memory_address_limit;
+
+       return 0;
+}
+
 /**
  * iort_dma_setup() - Set-up device DMA parameters.
  *
@@ -708,24 +726,26 @@ void iort_dma_setup(struct device *dev, u64 *dma_addr, u64 *dma_size)
 
        size = max(dev->coherent_dma_mask, dev->coherent_dma_mask + 1);
 
-       if (dev_is_pci(dev)) {
+       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;
-               }
+       else
+               ret = nc_dma_get_range(dev, &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;