Hi Christoph, Jim, On Wed, Sep 16, 2020 at 8:30 AM Christoph Hellwig <hch@xxxxxx> wrote: > From: Jim Quinlan <james.quinlan@xxxxxxxxxxxx> > > The new field 'dma_range_map' in struct device is used to facilitate the > use of single or multiple offsets between mapping regions of cpu addrs and > dma addrs. It subsumes the role of "dev->dma_pfn_offset" which was only > capable of holding a single uniform offset and had no region bounds > checking. > > The function of_dma_get_range() has been modified so that it takes a single > argument -- the device node -- and returns a map, NULL, or an error code. > The map is an array that holds the information regarding the DMA regions. > Each range entry contains the address offset, the cpu_start address, the > dma_start address, and the size of the region. > > of_dma_configure() is the typical manner to set range offsets but there are > a number of ad hoc assignments to "dev->dma_pfn_offset" in the kernel > driver code. These cases now invoke the function > dma_direct_set_offset(dev, cpu_addr, dma_addr, size). > > Signed-off-by: Jim Quinlan <james.quinlan@xxxxxxxxxxxx> > [hch: various interface cleanups] > Signed-off-by: Christoph Hellwig <hch@xxxxxx> > Tested-by: Nathan Chancellor <natechancellor@xxxxxxxxx> Thanks for your patch, which is now commit e0d072782c734d27 ("dma-mapping: introduce DMA range map, supplanting dma_pfn_offset") in v5.10-rc1, and to which I have bisected a PCIe failure on R-Car M2-W (r8a7791/koelsch). The first PCI host bridge, containing USB, probes fine: pci-rcar-gen2 ee090000.pci: host bridge /soc/pci@ee090000 ranges: pci-rcar-gen2 ee090000.pci: MEM 0x00ee080000..0x00ee08ffff -> 0x00ee080000 pci-rcar-gen2 ee090000.pci: PCI: revision 11 pci-rcar-gen2 ee090000.pci: PCI host bridge to bus 0000:00 pci_bus 0000:00: root bus resource [bus 00] pci_bus 0000:00: root bus resource [mem 0xee080000-0xee08ffff] pci 0000:00:00.0: [1033:0000] type 00 class 0x060000 pci 0000:00:00.0: reg 0x10: [mem 0xee090800-0xee090bff] pci 0000:00:00.0: reg 0x14: [mem 0x40000000-0x7fffffff pref] pci 0000:00:01.0: [1033:0035] type 00 class 0x0c0310 pci 0000:00:01.0: reg 0x10: [mem 0x00000000-0x00000fff] pci 0000:00:01.0: supports D1 D2 pci 0000:00:01.0: PME# supported from D0 D1 D2 D3hot pci 0000:00:02.0: [1033:00e0] type 00 class 0x0c0320 pci 0000:00:02.0: reg 0x10: [mem 0x00000000-0x000000ff] pci 0000:00:02.0: supports D1 D2 pci 0000:00:02.0: PME# supported from D0 D1 D2 D3hot PCI: bus0: Fast back to back transfers disabled pci 0000:00:01.0: BAR 0: assigned [mem 0xee080000-0xee080fff] pci 0000:00:02.0: BAR 0: assigned [mem 0xee081000-0xee0810ff] pci 0000:00:01.0: enabling device (0140 -> 0142) pci 0000:00:02.0: enabling device (0140 -> 0142) The second PCI host bridge, connected to an (empty) PCIe slot, fails: pci-rcar-gen2 ee0d0000.pci: host bridge /soc/pci@ee0d0000 ranges: pci-rcar-gen2 ee0d0000.pci: MEM 0x00ee0c0000..0x00ee0cffff -> 0x00ee0c0000 pci-rcar-gen2 ee0d0000.pci: PCI: revision 11 pci-rcar-gen2 ee0d0000.pci: PCI host bridge to bus 0001:01 pci_bus 0001:01: root bus resource [bus 01] pci_bus 0001:01: root bus resource [mem 0xee0c0000-0xee0cffff] pci 0001:01:00.0: [1033:0000] type 00 class 0x060000 pci 0001:01:00.0: reg 0x10: [mem 0xee0d0800-0xee0d0bff] pci 0001:01:00.0: reg 0x14: [mem 0x40000000-0x7fffffff pref] pci 0001:01:01.0: [1033:0035] type 00 class 0x0c0310 pci 0001:01:01.0: reg 0x10: [mem 0x00000000-0x00000fff] pci 0001:01:01.0: supports D1 D2 pci 0001:01:01.0: PME# supported from D0 D1 D2 D3hot pci 0001:01:02.0: [1033:00e0] type 00 class 0x0c0320 pci 0001:01:02.0: reg 0x10: [mem 0x00000000-0x000000ff] pci 0001:01:02.0: supports D1 D2 pci 0001:01:02.0: PME# supported from D0 D1 D2 D3hot PCI: bus1: Fast back to back transfers disabled pci 0001:01:01.0: BAR 0: assigned [mem 0xee0c0000-0xee0c0fff] pci 0001:01:02.0: BAR 0: assigned [mem 0xee0c1000-0xee0c10ff] pci 0001:01:01.0: enabling device (0140 -> 0142) pci 0001:01:02.0: enabling device (0140 -> 0142) -rcar-pcie fe000000.pcie: host bridge /soc/pcie@fe000000 ranges: -rcar-pcie fe000000.pcie: IO 0x00fe100000..0x00fe1fffff -> 0x0000000000 -rcar-pcie fe000000.pcie: MEM 0x00fe200000..0x00fe3fffff -> 0x00fe200000 -rcar-pcie fe000000.pcie: MEM 0x0030000000..0x0037ffffff -> 0x0030000000 -rcar-pcie fe000000.pcie: MEM 0x0038000000..0x003fffffff -> 0x0038000000 -rcar-pcie fe000000.pcie: IB MEM 0x0040000000..0x00bfffffff -> 0x0040000000 -rcar-pcie fe000000.pcie: IB MEM 0x0200000000..0x02ffffffff -> 0x0200000000 -rcar-pcie fe000000.pcie: PCIe link down +rcar-pcie fe000000.pcie: Adjusted size 0x0 invalid +rcar-pcie: probe of fe000000.pcie failed with error -22 I've posted a patch "[PATCH] dma-mapping: Fix 32-bit overflow with CONFIG_ARM_LPAE=n" (https://lore.kernel.org/linux-arm-kernel/20201026152755.3738293-1-geert+renesas@xxxxxxxxx/). Gr{oetje,eeting}s, Geert -- Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@xxxxxxxxxxxxxx In personal conversations with technical people, I call myself a hacker. But when I'm talking to journalists I just say "programmer" or something like that. -- Linus Torvalds