diff options
authorThomas Petazzoni <>2017-12-04 16:09:07 +0100
committerRich Felker <>2018-04-12 19:47:58 -0400
commitbf9c7e3d7924f72225f8f9c28438b4a711192ad3 (patch)
parent79e1c5e70b2a0fadb7b61c69de8442703e7d0dc4 (diff)
arch/sh: pcie-sh7786: handle non-zero DMA offsetsh-for-4.17
On SuperH, the base of the physical memory might be different from zero. In this case, PCI address zero will map to a non-zero physical address. In order to make sure that the DMA mapping API takes care of this DMA offset, we must fill in the dev->dma_pfn_offset field for PCI devices. This gets done in the pcibios_bus_add_device() hook, called for each new PCI device detected. The dma_pfn_offset global variable is re-calculated for every PCI controller available on the platform, but that's not an issue because its value will each time be exactly the same, as it only depends on the memory start address and memory size. Signed-off-by: Thomas Petazzoni <> Signed-off-by: Rich Felker <>
1 files changed, 8 insertions, 0 deletions
diff --git a/arch/sh/drivers/pci/pcie-sh7786.c b/arch/sh/drivers/pci/pcie-sh7786.c
index b8f411451647..382e7ecf4c82 100644
--- a/arch/sh/drivers/pci/pcie-sh7786.c
+++ b/arch/sh/drivers/pci/pcie-sh7786.c
@@ -33,6 +33,7 @@ struct sh7786_pcie_port {
static struct sh7786_pcie_port *sh7786_pcie_ports;
static unsigned int nr_ports;
+static unsigned long dma_pfn_offset;
static struct sh7786_pcie_hwops {
int (*core_init)(void);
@@ -370,6 +371,8 @@ static int __init pcie_init(struct sh7786_pcie_port *port)
memstart = ALIGN_DOWN(memstart, memsize);
memsize = roundup_pow_of_two(memend - memstart);
+ dma_pfn_offset = memstart >> PAGE_SHIFT;
* If there's more than 512MB of memory, we need to roll over to
@@ -485,6 +488,11 @@ int pcibios_map_platform_irq(const struct pci_dev *pdev, u8 slot, u8 pin)
return evt2irq(0xae0);
+void pcibios_bus_add_device(struct pci_dev *pdev)
+ pdev->dev.dma_pfn_offset = dma_pfn_offset;
static int __init sh7786_pcie_core_init(void)
/* Return the number of ports */