Hello Samuel, On Mon, Aug 19, 2019 at 10:23:01PM -0500, Samuel Holland wrote: > This series adds support for the "hardware message box" in sun8i, sun9i, > and sun50i SoCs, used for communication with the ARISC management > processor (the platform's equivalent of the ARM SCP). The end goal is to > use the arm_scpi driver as a client, communicating with firmware running > on the AR100 CPU, or to use the mailbox to forward NMIs that the > firmware picks up from R_INTC. > > Unfortunately, the ARM SCPI client no longer works with this driver > since it now exposes all 8 hardware FIFOs individually. The SCPI client > could be made to work (and I posted proof-of-concept code to that effect > with v1 of this series), but that is a low priority, as Linux does not > directly use SCPI with the current firmware version; all SCPI use goes > through ATF via PSCI. > > As requested in the comments to v3 of this patchset, a demo client is > provided in the final patch. This demo goes along with a toy firmware > which shows that the driver does indeed work for two-way communication > on all channels. To build the firmware component, run: I've tried using this driver with mainline arm_scpi driver (which is probably an expected future use, since crust provides SCPI interface). The problem I've found is that arm_scpi expects message box to be bi-directional, but this driver provides uni-directional interface. What do you think about making this driver provide bi-directional interface? We could halve the number of channels to 4 and mandate TX/RX configuration (from main CPU's PoV) as ABI. Otherwise it's impossible to use it with the arm_scpi driver. Or do you have any other ideas? I guess arm_scpi can be fixed to add a property that would make it possible to use single shmem with two mailboxes, one for rx and one for tx, but making sun6i mailbox have bi-directional interface sounds easier. regards, o. > git clone https://github.com/crust-firmware/meta meta > git clone -b mailbox-demo https://github.com/crust-firmware/crust meta/crust > cd meta > make > > That will by default produce a U-Boot + ATF + SCP firmware image in > [meta/]build/pinebook/u-boot-sunxi-with-spl.bin. See the top-level > README.md for more information, such as cross-compiler setup. > > I've now used this driver with three separate clients over the past two > years, and they all work. If there are no remaining concerns with the > driver, I'd like it to get merged. > > Even without the driver, the clock patches (1-2) can go in at any time. > > Changes from v3: > - Rebased on sunxi-next > - Added Rob's Reviewed-by for patch 3 > - Fixed a crash when receiving a message on a disabled channel > - Cleaned up some comments/formatting in the driver > - Fixed #mbox-cells in sunxi-h3-h5.dtsi (patch 7) > - Removed the irqchip example (no longer relevant to the fw design) > - Added a demo/example client that uses the driver and a toy firmware > > Changes from v2: > - Merge patches 1-3 > - Add a comment in the code explaining the CLK_IS_CRITICAL usage > - Add a patch to mark the AR100 clocks as critical > - Use YAML for the device tree binding > - Include a not-for-merge example usage of the mailbox > > Changes from v1: > - Marked message box clocks as critical instead of hacks in the driver > - 8 unidirectional channels instead of 4 bidirectional pairs > - Use per-SoC compatible strings and an A31 fallback compatible > - Dropped the mailbox framework patch > - Include DT patches for SoCs that document the message box > > Samuel Holland (10): > clk: sunxi-ng: Mark msgbox clocks as critical > clk: sunxi-ng: Mark AR100 clocks as critical > dt-bindings: mailbox: Add a sunxi message box binding > mailbox: sunxi-msgbox: Add a new mailbox driver > ARM: dts: sunxi: a80: Add msgbox node > ARM: dts: sunxi: a83t: Add msgbox node > ARM: dts: sunxi: h3/h5: Add msgbox node > arm64: dts: allwinner: a64: Add msgbox node > arm64: dts: allwinner: h6: Add msgbox node > [DO NOT MERGE] drivers: firmware: msgbox demo > > .../mailbox/allwinner,sunxi-msgbox.yaml | 79 +++++ > arch/arm/boot/dts/sun8i-a83t.dtsi | 10 + > arch/arm/boot/dts/sun9i-a80.dtsi | 10 + > arch/arm/boot/dts/sunxi-h3-h5.dtsi | 10 + > arch/arm64/boot/dts/allwinner/sun50i-a64.dtsi | 34 ++ > arch/arm64/boot/dts/allwinner/sun50i-h5.dtsi | 24 ++ > arch/arm64/boot/dts/allwinner/sun50i-h6.dtsi | 10 + > drivers/clk/sunxi-ng/ccu-sun50i-a64.c | 3 +- > drivers/clk/sunxi-ng/ccu-sun50i-h6-r.c | 2 +- > drivers/clk/sunxi-ng/ccu-sun50i-h6.c | 3 +- > drivers/clk/sunxi-ng/ccu-sun8i-a23.c | 3 +- > drivers/clk/sunxi-ng/ccu-sun8i-a33.c | 3 +- > drivers/clk/sunxi-ng/ccu-sun8i-a83t.c | 3 +- > drivers/clk/sunxi-ng/ccu-sun8i-h3.c | 3 +- > drivers/clk/sunxi-ng/ccu-sun8i-r.c | 2 +- > drivers/clk/sunxi-ng/ccu-sun9i-a80.c | 3 +- > drivers/firmware/Kconfig | 6 + > drivers/firmware/Makefile | 1 + > drivers/firmware/sunxi_msgbox_demo.c | 307 +++++++++++++++++ > drivers/mailbox/Kconfig | 10 + > drivers/mailbox/Makefile | 2 + > drivers/mailbox/sunxi-msgbox.c | 323 ++++++++++++++++++ > 22 files changed, 842 insertions(+), 9 deletions(-) > create mode 100644 Documentation/devicetree/bindings/mailbox/allwinner,sunxi-msgbox.yaml > create mode 100644 drivers/firmware/sunxi_msgbox_demo.c > create mode 100644 drivers/mailbox/sunxi-msgbox.c > > -- > 2.21.0 > > _______________________________________________ > linux-arm-kernel mailing list > linux-arm-kernel@xxxxxxxxxxxxxxxxxxx > http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
