sparc64: refactor the ali DMA quirk

Do the quirk first in the dma_supported routines, as we don't need
any of the other checks for it, and remove the duplicate mask checking
that is already done by the callers.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: David S. Miller <davem@davemloft.net>

arch/sparc/kernel/iommu.c

@@ -745,14 +745,13 @@ static int dma_4u_supported(struct device *dev, u64 device_mask)
 {
 	struct iommu *iommu = dev->archdata.iommu;
 
+	if (ali_sound_dma_hack(dev, device_mask))
+		return 1;
+
 	if (device_mask > DMA_BIT_MASK(32))
 		return 0;
 	if ((device_mask & iommu->dma_addr_mask) == iommu->dma_addr_mask)
 		return 1;
-#ifdef CONFIG_PCI
-	if (dev_is_pci(dev))
-		return pci64_dma_supported(to_pci_dev(dev), device_mask);
-#endif
 	return 0;
 }
 

arch/sparc/kernel/kernel.h

@@ -45,7 +45,11 @@ void __irq_entry smp_receive_signal_client(int irq, struct pt_regs *regs);
 void __irq_entry smp_kgdb_capture_client(int irq, struct pt_regs *regs);
 
 /* pci.c */
-int pci64_dma_supported(struct pci_dev *pdev, u64 device_mask);
+#ifdef CONFIG_PCI
+int ali_sound_dma_hack(struct device *dev, u64 device_mask);
+#else
+#define ali_sound_dma_hack(dev, mask)	(0)
+#endif
 
 /* signal32.c */
 void do_sigreturn32(struct pt_regs *regs);

arch/sparc/kernel/pci.c

@@ -956,51 +956,35 @@ void arch_teardown_msi_irq(unsigned int irq)
 }
 #endif /* !(CONFIG_PCI_MSI) */
 
-static void ali_sound_dma_hack(struct pci_dev *pdev, int set_bit)
+/* ALI sound chips generate 31-bits of DMA, a special register
+ * determines what bit 31 is emitted as.
+ */
+int ali_sound_dma_hack(struct device *dev, u64 device_mask)
 {
+	struct iommu *iommu = dev->archdata.iommu;
 	struct pci_dev *ali_isa_bridge;
 	u8 val;
 
-	/* ALI sound chips generate 31-bits of DMA, a special register
-	 * determines what bit 31 is emitted as.
-	 */
+	if (!dev_is_pci(dev))
+		return 0;
+
+	if (to_pci_dev(dev)->vendor != PCI_VENDOR_ID_AL ||
+	    to_pci_dev(dev)->device != PCI_DEVICE_ID_AL_M5451 ||
+	    device_mask != 0x7fffffff)
+		return 0;
+
 	ali_isa_bridge = pci_get_device(PCI_VENDOR_ID_AL,
 					 PCI_DEVICE_ID_AL_M1533,
 					 NULL);
 
 	pci_read_config_byte(ali_isa_bridge, 0x7e, &val);
-	if (set_bit)
+	if (iommu->dma_addr_mask & 0x80000000)
 		val |= 0x01;
 	else
 		val &= ~0x01;
 	pci_write_config_byte(ali_isa_bridge, 0x7e, val);
 	pci_dev_put(ali_isa_bridge);
-}
-
-int pci64_dma_supported(struct pci_dev *pdev, u64 device_mask)
-{
-	u64 dma_addr_mask;
-
-	if (pdev == NULL) {
-		dma_addr_mask = 0xffffffff;
-	} else {
-		struct iommu *iommu = pdev->dev.archdata.iommu;
-
-		dma_addr_mask = iommu->dma_addr_mask;
-
-		if (pdev->vendor == PCI_VENDOR_ID_AL &&
-		    pdev->device == PCI_DEVICE_ID_AL_M5451 &&
-		    device_mask == 0x7fffffff) {
-			ali_sound_dma_hack(pdev,
-					   (dma_addr_mask & 0x80000000) != 0);
 	return 1;
-		}
-	}
-
-	if (device_mask >= (1UL << 32UL))
-		return 0;
-
-	return (device_mask & dma_addr_mask) == dma_addr_mask;
 }
 
 void pci_resource_to_user(const struct pci_dev *pdev, int bar,

arch/sparc/kernel/pci_sun4v.c

@@ -676,6 +676,9 @@ static int dma_4v_supported(struct device *dev, u64 device_mask)
 	struct iommu *iommu = dev->archdata.iommu;
 	u64 dma_addr_mask = iommu->dma_addr_mask;
 
+	if (ali_sound_dma_hack(dev, device_mask))
+		return 1;
+
 	if (device_mask > DMA_BIT_MASK(32)) {
 		if (iommu->atu)
 			dma_addr_mask = iommu->atu->dma_addr_mask;
@@ -685,7 +688,7 @@ static int dma_4v_supported(struct device *dev, u64 device_mask)
 
 	if ((device_mask & dma_addr_mask) == dma_addr_mask)
 		return 1;
-	return pci64_dma_supported(to_pci_dev(dev), device_mask);
+	return 0;
 }
 
 static const struct dma_map_ops sun4v_dma_ops = {