sh/PCI: Pass GAPSPCI_DMA_BASE CPU & bus address to dma_declare_coherent_memory()
dma_declare_coherent_memory() needs both the CPU physical address and the
bus address of the device memory. They are the same on this platform, but
in general we should use pcibios_resource_to_bus() to account for any
address translation done by the PCI host bridge.
This makes no difference on Dreamcast, but is safer if the usage is copied
to future drivers.
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
CC: Magnus Damm <damm@opensource.se>
CC: linux-sh@vger.kernel.org
diff --git a/arch/sh/drivers/pci/fixups-dreamcast.c b/arch/sh/drivers/pci/fixups-dreamcast.c
index d6cde70..1d1c5a2 100644
--- a/arch/sh/drivers/pci/fixups-dreamcast.c
+++ b/arch/sh/drivers/pci/fixups-dreamcast.c
@@ -31,6 +31,8 @@
static void gapspci_fixup_resources(struct pci_dev *dev)
{
struct pci_channel *p = dev->sysdata;
+ struct resource res;
+ struct pci_bus_region region;
printk(KERN_NOTICE "PCI: Fixing up device %s\n", pci_name(dev));
@@ -50,11 +52,21 @@
/*
* Redirect dma memory allocations to special memory window.
+ *
+ * If this GAPSPCI region were mapped by a BAR, the CPU
+ * phys_addr_t would be pci_resource_start(), and the bus
+ * address would be pci_bus_address(pci_resource_start()).
+ * But apparently there's no BAR mapping it, so we just
+ * "know" its CPU address is GAPSPCI_DMA_BASE.
*/
+ res.start = GAPSPCI_DMA_BASE;
+ res.end = GAPSPCI_DMA_BASE + GAPSPCI_DMA_SIZE - 1;
+ res.flags = IORESOURCE_MEM;
+ pcibios_resource_to_bus(dev->bus, ®ion, &res);
BUG_ON(!dma_declare_coherent_memory(&dev->dev,
- GAPSPCI_DMA_BASE,
- GAPSPCI_DMA_BASE,
- GAPSPCI_DMA_SIZE,
+ res.start,
+ region.start,
+ resource_size(&res),
DMA_MEMORY_MAP |
DMA_MEMORY_EXCLUSIVE));
break;
