From: Phil Edworthy <[email protected]> The PCIe DMA controller on RCar Gen2 and earlier is on 32bit bus, so limit the DMA range to 32bit.
Signed-off-by: Phil Edworthy <[email protected]> Signed-off-by: Marek Vasut <[email protected]> Cc: Arnd Bergmann <[email protected]> Cc: Geert Uytterhoeven <[email protected]> Cc: Phil Edworthy <[email protected]> Cc: Simon Horman <[email protected]> Cc: Wolfram Sang <[email protected]> Cc: [email protected] To: [email protected] --- NOTE: I'm aware of https://patchwork.kernel.org/patch/9495895/ , but the discussion seems to have gone way off, so I'm sending this as a RFC. Any feedback on how to do this limiting properly would be nice. --- drivers/pci/host/pcie-rcar.c | 28 ++++++++++++++++++++++++++++ 1 file changed, 28 insertions(+) diff --git a/drivers/pci/host/pcie-rcar.c b/drivers/pci/host/pcie-rcar.c index c3eab0b95290..db2b16f40bc1 100644 --- a/drivers/pci/host/pcie-rcar.c +++ b/drivers/pci/host/pcie-rcar.c @@ -1325,3 +1325,31 @@ static struct platform_driver rcar_pcie_driver = { .probe = rcar_pcie_probe, }; builtin_platform_driver(rcar_pcie_driver); + +static int rcar_pcie_pci_notifier(struct notifier_block *nb, + unsigned long action, void *data) +{ + struct device *dev = data; + + switch (action) { + case BUS_NOTIFY_BOUND_DRIVER: + /* Force the DMA mask to lower 32-bits */ + dma_set_mask_and_coherent(dev, DMA_BIT_MASK(32)); + break; + default: + return NOTIFY_DONE; + } + + return NOTIFY_OK; +} + +static struct notifier_block device_nb = { + .notifier_call = rcar_pcie_pci_notifier, +}; + +static int __init register_rcar_pcie_pci_notifier(void) +{ + return bus_register_notifier(&pci_bus_type, &device_nb); +} + +arch_initcall(register_rcar_pcie_pci_notifier); -- 2.16.2
