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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
This commit is contained in:
Bjorn Helgaas 2014-05-20 16:54:23 -06:00
parent 88a984ba07
commit ace4b3fd67
1 changed files with 15 additions and 3 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

18
arch/sh/drivers/pci/fixups-dreamcast.c
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@ -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 @@ static void gapspci_fixup_resources(struct pci_dev *dev)
/*
* 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, &region, &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;