| Message ID | cover.1721999833.git.geert+renesas@glider.be |
|---|---|
| Headers | show |
| Series | Add Renesas R-Car Gen4 E-FUSE support | expand |
Hi Srinivas, Gentle ping, any comments from the nvmem side? Thank you! On Fri, Jul 26, 2024 at 3:38 PM Geert Uytterhoeven <geert+renesas@glider.be> wrote: > R-Car Gen3/Gen4 SoCs contain fuses indicating hardware support or > hardware parameters. Unfortunately the various SoCs require different > mechanisms to read the state of the fuses: > - On R-Car Gen3, the fuse monitor registers are in the middle of the > Pin Function Controller (PFC) register block, > - On R-Car V3U and S4-8, the E-FUSE non-volatile memory is accessible > through a separate register block in the PFC, > - On R-Car V4H and V4M, the E-FUSE non-volatile memory is accessible > through the second register block of OTP_MEM. > > As the first variant is quite different from the other two, and there is > currently no use case requiring support for it, this patch series adds > support for the last 2 variants only. > > Note that the first two revisions of this series implemented only basic > nvmem support, and a custom in-kernel API, mimicked after the > fuse-tregra driver. Then, Arnd told me on IRC that the R-Car E-FUSE > driver should use the nvmem framework fully. > > The fuses' states can be read using the nvmem subsystem: > - In kernelspace, through the nvmem_cell_*() API. > A first known use case is reading tuning parameters for the > Universal Flash Storage controller on R-Car S4-8 ES1.2. > - In userspace, through sysfs. E.g. on R-Car S4-8 ES1.2: > / # hd /sys/bus/nvmem/devices/rcar-fuse/nvmem > 00000000 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 |................| > * > 000000e0 00 00 00 00 fe 00 00 00 00 00 00 00 00 00 00 00 |....�...........| > 000000f0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 |................| > * > 00000140 00 00 00 00 23 51 23 51 52 98 52 98 00 00 00 00 |....#Q#QR�R�....| > 00000150 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 |................| > * > 00000200 > > Changes compared to v2[1]: > - Dropped accepted dt-bindings, > - Drop "pinctrl: renesas: Add R-Car Gen3 fuse support", > - New patch "dt-bindings: fuse: Move renesas,rcar-{efuse,otp} to > nvmem", > - Drop superfluous semicolon, > - Drop the custom rcar_fuse_read() kernel API, in favor of the > standard nvmem_cell_*() API, > - Drop support for explicitly-instantiated platform devices with > accompanying platform data, which would be needed to support fuses > tightly integrated with the Pin Function Controller on R-Car Gen3 > SoCs. It can be added when a use case shows up. > - Move from drivers/soc/renesas/ to drivers/nvmem/, > - Register the full register block that contains the E-FUSE data > registers with the nvmem subsystem, but use keepouts to ignore all > registers before the first or after the last documented data > register. Undocumented registers in between are still accessible. > - Replace offset/nregs in rcar_fuse_data by start/end, > - Use __ioread32_copy() helper, > - Initialize most fields of struct nvmem_config in its declaration, > - Rename nvmem device from "fuse" to "rcar-fuse", > - Use NVMEM_DEVID_NONE, > - Add an entry to the MAINTAINERS file, > - Fix reg size, > - New patch "arm64: dts: renesas: r8a779f4: Add UFS tuning parameters > in E-FUSE". > > Changes compared to v1[2]: > - Drop RFC state and broaden audience, > - Fix typo in one-line summary, > - Add Reviewed-by. > > This has been tested on R-Car V3U, S4-8 ES1.0 and ES1.2, V4H, and V4M. > > Thanks for your comments! > > [1] https://lore.kernel.org/cover.1716974502.git.geert+renesas@glider.be > [2] https://lore.kernel.org/cover.1714642390.git.geert+renesas@glider.be > > Geert Uytterhoeven (7): > dt-bindings: fuse: Move renesas,rcar-{efuse,otp} to nvmem > nvmem: Add R-Car E-FUSE driver > arm64: dts: renesas: r8a779a0: Add E-FUSE node > arm64: dts: renesas: r8a779f0: Add E-FUSE node > arm64: dts: renesas: r8a779f4: Add UFS tuning parameters in E-FUSE > arm64: dts: renesas: r8a779g0: Add OTP_MEM node > arm64: dts: renesas: r8a779h0: Add OTP_MEM node > > .../{fuse => nvmem}/renesas,rcar-efuse.yaml | 35 +++-- > .../{fuse => nvmem}/renesas,rcar-otp.yaml | 17 ++- > MAINTAINERS | 2 + > arch/arm64/boot/dts/renesas/r8a779a0.dtsi | 8 + > arch/arm64/boot/dts/renesas/r8a779f0.dtsi | 8 + > arch/arm64/boot/dts/renesas/r8a779f4.dtsi | 12 ++ > arch/arm64/boot/dts/renesas/r8a779g0.dtsi | 5 + > arch/arm64/boot/dts/renesas/r8a779h0.dtsi | 5 + > drivers/nvmem/Kconfig | 11 ++ > drivers/nvmem/Makefile | 2 + > drivers/nvmem/rcar-efuse.c | 142 ++++++++++++++++++ > 11 files changed, 230 insertions(+), 17 deletions(-) > rename Documentation/devicetree/bindings/{fuse => nvmem}/renesas,rcar-efuse.yaml (54%) > rename Documentation/devicetree/bindings/{fuse => nvmem}/renesas,rcar-otp.yaml (60%) > create mode 100644 drivers/nvmem/rcar-efuse.c > > -- > 2.34.1
Hi all, R-Car Gen3/Gen4 SoCs contain fuses indicating hardware support or hardware parameters. Unfortunately the various SoCs require different mechanisms to read the state of the fuses: - On R-Car Gen3, the fuse monitor registers are in the middle of the Pin Function Controller (PFC) register block, - On R-Car V3U and S4-8, the E-FUSE non-volatile memory is accessible through a separate register block in the PFC, - On R-Car V4H and V4M, the E-FUSE non-volatile memory is accessible through the second register block of OTP_MEM. As the first variant is quite different from the other two, and there is currently no use case requiring support for it, this patch series adds support for the last 2 variants only. Note that the first two revisions of this series implemented only basic nvmem support, and a custom in-kernel API, mimicked after the fuse-tregra driver. Then, Arnd told me on IRC that the R-Car E-FUSE driver should use the nvmem framework fully. The fuses' states can be read using the nvmem subsystem: - In kernelspace, through the nvmem_cell_*() API. A first known use case is reading tuning parameters for the Universal Flash Storage controller on R-Car S4-8 ES1.2. - In userspace, through sysfs. E.g. on R-Car S4-8 ES1.2: / # hd /sys/bus/nvmem/devices/rcar-fuse/nvmem 00000000 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 |................| * 000000e0 00 00 00 00 fe 00 00 00 00 00 00 00 00 00 00 00 |....�...........| 000000f0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 |................| * 00000140 00 00 00 00 23 51 23 51 52 98 52 98 00 00 00 00 |....#Q#QR�R�....| 00000150 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 |................| * 00000200 Changes compared to v2[1]: - Dropped accepted dt-bindings, - Drop "pinctrl: renesas: Add R-Car Gen3 fuse support", - New patch "dt-bindings: fuse: Move renesas,rcar-{efuse,otp} to nvmem", - Drop superfluous semicolon, - Drop the custom rcar_fuse_read() kernel API, in favor of the standard nvmem_cell_*() API, - Drop support for explicitly-instantiated platform devices with accompanying platform data, which would be needed to support fuses tightly integrated with the Pin Function Controller on R-Car Gen3 SoCs. It can be added when a use case shows up. - Move from drivers/soc/renesas/ to drivers/nvmem/, - Register the full register block that contains the E-FUSE data registers with the nvmem subsystem, but use keepouts to ignore all registers before the first or after the last documented data register. Undocumented registers in between are still accessible. - Replace offset/nregs in rcar_fuse_data by start/end, - Use __ioread32_copy() helper, - Initialize most fields of struct nvmem_config in its declaration, - Rename nvmem device from "fuse" to "rcar-fuse", - Use NVMEM_DEVID_NONE, - Add an entry to the MAINTAINERS file, - Fix reg size, - New patch "arm64: dts: renesas: r8a779f4: Add UFS tuning parameters in E-FUSE". Changes compared to v1[2]: - Drop RFC state and broaden audience, - Fix typo in one-line summary, - Add Reviewed-by. This has been tested on R-Car V3U, S4-8 ES1.0 and ES1.2, V4H, and V4M. Thanks for your comments! [1] https://lore.kernel.org/cover.1716974502.git.geert+renesas@glider.be [2] https://lore.kernel.org/cover.1714642390.git.geert+renesas@glider.be Geert Uytterhoeven (7): dt-bindings: fuse: Move renesas,rcar-{efuse,otp} to nvmem nvmem: Add R-Car E-FUSE driver arm64: dts: renesas: r8a779a0: Add E-FUSE node arm64: dts: renesas: r8a779f0: Add E-FUSE node arm64: dts: renesas: r8a779f4: Add UFS tuning parameters in E-FUSE arm64: dts: renesas: r8a779g0: Add OTP_MEM node arm64: dts: renesas: r8a779h0: Add OTP_MEM node .../{fuse => nvmem}/renesas,rcar-efuse.yaml | 35 +++-- .../{fuse => nvmem}/renesas,rcar-otp.yaml | 17 ++- MAINTAINERS | 2 + arch/arm64/boot/dts/renesas/r8a779a0.dtsi | 8 + arch/arm64/boot/dts/renesas/r8a779f0.dtsi | 8 + arch/arm64/boot/dts/renesas/r8a779f4.dtsi | 12 ++ arch/arm64/boot/dts/renesas/r8a779g0.dtsi | 5 + arch/arm64/boot/dts/renesas/r8a779h0.dtsi | 5 + drivers/nvmem/Kconfig | 11 ++ drivers/nvmem/Makefile | 2 + drivers/nvmem/rcar-efuse.c | 142 ++++++++++++++++++ 11 files changed, 230 insertions(+), 17 deletions(-) rename Documentation/devicetree/bindings/{fuse => nvmem}/renesas,rcar-efuse.yaml (54%) rename Documentation/devicetree/bindings/{fuse => nvmem}/renesas,rcar-otp.yaml (60%) create mode 100644 drivers/nvmem/rcar-efuse.c