From be7f3f901c619e24c93b8044c074306feedd8ee9 Mon Sep 17 00:00:00 2001 From: Arnd Bergmann Date: Thu, 25 Aug 2022 10:51:42 +0200 Subject: ARM: footbridge: remove custom DMA address handling Footbridge is the last Arm platform that has its own __virt_to_bus()/__bus_to_virt()/phys_to_dma()/dma_to_phys() abstraction, but this is just a simple offset now. For PCI devices, the offset that is programmed into the PCI bridge must also be set in each device using dma_direct_set_offset(). As Arm does not have a pcibios_bus_add_device() helper yet, just use a bus notifier for this. For the ISA DMA, drivers now pass a non-translated physical address into set_dma_addr(), so they have to be converted back with the corresponding isa_bus_to_virt() function and then into the correct bus address with the offset using the isa_dma_dev. Tested-by: Marc Zyngier Signed-off-by: Arnd Bergmann --- arch/arm/include/asm/hardware/dec21285.h | 7 +++++++ 1 file changed, 7 insertions(+) (limited to 'arch/arm/include/asm/hardware') diff --git a/arch/arm/include/asm/hardware/dec21285.h b/arch/arm/include/asm/hardware/dec21285.h index eee390e8d4dc..894f2a635cbb 100644 --- a/arch/arm/include/asm/hardware/dec21285.h +++ b/arch/arm/include/asm/hardware/dec21285.h @@ -22,6 +22,13 @@ #define DC21285_IO(x) (x) #endif +/* + * The footbridge is programmed to expose the system RAM at 0xe0000000. + * The requirement is that the RAM isn't placed at bus address 0, which + * would clash with VGA cards. + */ +#define BUS_OFFSET 0xe0000000 + #define CSR_PCICMD DC21285_IO(0x0004) #define CSR_CLASSREV DC21285_IO(0x0008) #define CSR_PCICACHELINESIZE DC21285_IO(0x000c) -- cgit v1.2.3