Hi All, this series tries to address one of the issues blocking us from upstreaming Broadcom's STB PCIe controller[1]. Namely, the fact that devices not represented in DT which sit behind a PCI bus fail to get the bus' DMA addressing constraints.
This is due to the fact that of_dma_configure() assumes it's receiving a DT node representing the device being configured, as opposed to the PCIe bridge node we currently pass. This causes the code to directly jump into PCI's parent node when checking for 'dma-ranges' and misses whatever was set there.
To address this I create a new API in OF - inspired from Robin Murphys original proposal[2] - which accepts a bus DT node as it's input in order to configure a device's DMA constraints. The changes go deep into of/address.c's implementation, as a device being having a DT node assumption was pretty strong.
On top of this work, I also cleaned up of_dma_configure() removing its redundant arguments and creating an alternative function for the special cases not applicable to either the above case or the default usage.
IMO the resulting functions are more explicit. They will probably surface some hacky usages that can be properly fixed as I show with the DT fixes on the Layerscape platform.
This was also tested on a Raspberry Pi 4 with a custom PCIe driver and on a Seattle AMD board.
Regards, Nicolas
[1] https://patchwork.kernel.org/patch/9650345/#20294961 [2] https://patchwork.kernel.org/patch/9650345/
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Nicolas Saenz Julienne (11): of: address: clean-up unused variable in of_dma_get_range() of: base: introduce __of_n_*_cells_parent() of: address: use parent DT node in bus->count_cells() of: address: introduce of_translate_dma_address_parent() of: expose __of_get_dma_parent() to OF subsystem of: address: use parent OF node in of_dma_get_range() dts: arm64: layerscape: add dma-ranges property to qoric-mc node dts: arm64: layerscape: add dma-ranges property to pcie nodes of: device: remove comment in of_dma_configure() of: device: introduce of_dma_configure_parent() of: simplify of_dma_config()'s arguments
.../arm64/boot/dts/freescale/fsl-ls1088a.dtsi | 1 + .../arm64/boot/dts/freescale/fsl-ls208xa.dtsi | 5 + .../arm64/boot/dts/freescale/fsl-lx2160a.dtsi | 1 + drivers/base/platform.c | 2 +- drivers/bcma/main.c | 2 +- drivers/bus/fsl-mc/fsl-mc-bus.c | 2 +- drivers/dma/qcom/hidma_mgmt.c | 2 +- drivers/gpu/drm/etnaviv/etnaviv_drv.c | 2 +- drivers/gpu/drm/msm/adreno/a6xx_gmu.c | 2 +- drivers/gpu/drm/sun4i/sun4i_backend.c | 2 +- drivers/gpu/drm/xen/xen_drm_front.c | 2 +- drivers/gpu/host1x/bus.c | 4 +- drivers/media/platform/qcom/venus/firmware.c | 2 +- drivers/media/platform/s5p-mfc/s5p_mfc.c | 2 +- drivers/of/address.c | 136 +++++++++--------- drivers/of/base.c | 69 +++++++-- drivers/of/device.c | 59 +++++++- drivers/of/of_private.h | 5 + drivers/pci/pci-driver.c | 3 +- drivers/xen/gntdev.c | 2 +- include/linux/of_address.h | 8 +- include/linux/of_device.h | 23 ++- 22 files changed, 223 insertions(+), 113 deletions(-)