Merge tag 'dma-mapping-4.19-2' of git://git.infradead.org/users/hch/dma-mapping

Pull dma-mapping fixes from Christoph Hellwig:
 "A few fixes for the fallout of being a little more pedantic about dma
  masks"

* tag 'dma-mapping-4.19-2' of git://git.infradead.org/users/hch/dma-mapping:
  of/platform: initialise AMBA default DMA masks
  sparc: set a default 32-bit dma mask for OF devices
  kernel/dma/direct: take DMA offset into account in dma_direct_supported

4 files changed, 13 insertions, 2 deletions

diff --git a/arch/sparc/kernel/of_device_32.c b/arch/sparc/kernel/of_device_32.c
index 3641a294ed54..e4abe9b8f97a 100644
--- a/arch/sparc/kernel/of_device_32.c
+++ b/arch/sparc/kernel/of_device_32.c
@@ -9,6 +9,7 @@
 #include <linux/irq.h>
 #include <linux/of_device.h>
 #include <linux/of_platform.h>
+#include <linux/dma-mapping.h>
 #include <asm/leon.h>
 #include <asm/leon_amba.h>
 
@@ -381,6 +382,9 @@ static struct platform_device * __init scan_one_device(struct device_node *dp,
         else
                 dev_set_name(&op->dev, "%08x", dp->phandle);
 
+        op->dev.coherent_dma_mask = DMA_BIT_MASK(32);
+        op->dev.dma_mask = &op->dev.coherent_dma_mask;
+
         if (of_device_register(op)) {
                 printk("%s: Could not register of device.\n",
                        dp->full_name);
diff --git a/arch/sparc/kernel/of_device_64.c b/arch/sparc/kernel/of_device_64.c
index 44e4d4435bed..6df6086968c6 100644
--- a/arch/sparc/kernel/of_device_64.c
+++ b/arch/sparc/kernel/of_device_64.c
@@ -2,6 +2,7 @@
 #include <linux/string.h>
 #include <linux/kernel.h>
 #include <linux/of.h>
+#include <linux/dma-mapping.h>
 #include <linux/init.h>
 #include <linux/export.h>
 #include <linux/mod_devicetable.h>
@@ -675,6 +676,8 @@ static struct platform_device * __init scan_one_device(struct device_node *dp,
                 dev_set_name(&op->dev, "root");
         else
                 dev_set_name(&op->dev, "%08x", dp->phandle);
+        op->dev.coherent_dma_mask = DMA_BIT_MASK(32);
+        op->dev.dma_mask = &op->dev.coherent_dma_mask;
 
         if (of_device_register(op)) {
                 printk("%s: Could not register of device.\n",
diff --git a/drivers/of/platform.c b/drivers/of/platform.c
index 7ba90c290a42..6c59673933e9 100644
--- a/drivers/of/platform.c
+++ b/drivers/of/platform.c
@@ -241,6 +241,10 @@ static struct amba_device *of_amba_device_create(struct device_node *node,
         if (!dev)
                 goto err_clear_flag;
 
+        /* AMBA devices only support a single DMA mask */
+        dev->dev.coherent_dma_mask = DMA_BIT_MASK(32);
+        dev->dev.dma_mask = &dev->dev.coherent_dma_mask;
+
         /* setup generic device info */
         dev->dev.of_node = of_node_get(node);
         dev->dev.fwnode = &node->fwnode;
diff --git a/kernel/dma/direct.c b/kernel/dma/direct.c
index 1c35b7b945d0..de87b0282e74 100644
--- a/kernel/dma/direct.c
+++ b/kernel/dma/direct.c
@@ -168,7 +168,7 @@ int dma_direct_map_sg(struct device *dev, struct scatterlist *sgl, int nents,
 int dma_direct_supported(struct device *dev, u64 mask)
 {
 #ifdef CONFIG_ZONE_DMA
-        if (mask < DMA_BIT_MASK(ARCH_ZONE_DMA_BITS))
+        if (mask < phys_to_dma(dev, DMA_BIT_MASK(ARCH_ZONE_DMA_BITS)))
                 return 0;
 #else
         /*
@@ -177,7 +177,7 @@ int dma_direct_supported(struct device *dev, u64 mask)
          * memory, or by providing a ZONE_DMA32.  If neither is the case, the
          * architecture needs to use an IOMMU instead of the direct mapping.
          */
-        if (mask < DMA_BIT_MASK(32))
+        if (mask < phys_to_dma(dev, DMA_BIT_MASK(32)))
                 return 0;
 #endif
         /*