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authorLinus Torvalds <torvalds@linux-foundation.org>2022-03-25 10:11:38 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2022-03-25 10:11:38 -0700
commitaa5b537b0ecc16992577b013f11112d54c7ce869 (patch)
treeac9f6ce6c8c5b4722501cb36e95b3c0a35aa933e /Documentation/devicetree/bindings/pwm
parentMerge tag 's390-5.18-1' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux (diff)
parentRISC-V: add support for restartable sequences (diff)
downloadlinux-dev-aa5b537b0ecc16992577b013f11112d54c7ce869.tar.xz
linux-dev-aa5b537b0ecc16992577b013f11112d54c7ce869.zip
Merge tag 'riscv-for-linus-5.18-mw0' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux
Pull RISC-V updates from Palmer Dabbelt: - Support for Sv57-based virtual memory. - Various improvements for the MicroChip PolarFire SOC and the associated Icicle dev board, which should allow upstream kernels to boot without any additional modifications. - An improved memmove() implementation. - Support for the new Ssconfpmf and SBI PMU extensions, which allows for a much more useful perf implementation on RISC-V systems. - Support for restartable sequences. * tag 'riscv-for-linus-5.18-mw0' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux: (36 commits) rseq/selftests: Add support for RISC-V RISC-V: Add support for restartable sequence MAINTAINERS: Add entry for RISC-V PMU drivers Documentation: riscv: Remove the old documentation RISC-V: Add sscofpmf extension support RISC-V: Add perf platform driver based on SBI PMU extension RISC-V: Add RISC-V SBI PMU extension definitions RISC-V: Add a simple platform driver for RISC-V legacy perf RISC-V: Add a perf core library for pmu drivers RISC-V: Add CSR encodings for all HPMCOUNTERS RISC-V: Remove the current perf implementation RISC-V: Improve /proc/cpuinfo output for ISA extensions RISC-V: Do no continue isa string parsing without correct XLEN RISC-V: Implement multi-letter ISA extension probing framework RISC-V: Extract multi-letter extension names from "riscv, isa" RISC-V: Minimal parser for "riscv, isa" strings RISC-V: Correctly print supported extensions riscv: Fixed misaligned memory access. Fixed pointer comparison. MAINTAINERS: update riscv/microchip entry riscv: dts: microchip: add new peripherals to icicle kit device tree ...
Diffstat (limited to 'Documentation/devicetree/bindings/pwm')
-rw-r--r--Documentation/devicetree/bindings/pwm/microchip,corepwm.yaml81
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diff --git a/Documentation/devicetree/bindings/pwm/microchip,corepwm.yaml b/Documentation/devicetree/bindings/pwm/microchip,corepwm.yaml
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+++ b/Documentation/devicetree/bindings/pwm/microchip,corepwm.yaml
@@ -0,0 +1,81 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/pwm/microchip,corepwm.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Microchip IP corePWM controller bindings
+
+maintainers:
+ - Conor Dooley <conor.dooley@microchip.com>
+
+description: |
+ corePWM is an 16 channel pulse width modulator FPGA IP
+
+ https://www.microsemi.com/existing-parts/parts/152118
+
+allOf:
+ - $ref: pwm.yaml#
+
+properties:
+ compatible:
+ items:
+ - const: microchip,corepwm-rtl-v4
+
+ reg:
+ maxItems: 1
+
+ clocks:
+ maxItems: 1
+
+ "#pwm-cells":
+ const: 2
+
+ microchip,sync-update-mask:
+ description: |
+ Depending on how the IP is instantiated, there are two modes of operation.
+ In synchronous mode, all channels are updated at the beginning of the PWM period,
+ and in asynchronous mode updates happen as the control registers are written.
+ A 16 bit wide "SHADOW_REG_EN" parameter of the IP core controls whether synchronous
+ mode is possible for each channel, and is set by the bitstream programmed to the
+ FPGA. If the IP core is instantiated with SHADOW_REG_ENx=1, both registers that
+ control the duty cycle for channel x have a second "shadow"/buffer reg synthesised.
+ At runtime a bit wide register exposed to APB can be used to toggle on/off
+ synchronised mode for all channels it has been synthesised for.
+ Each bit of "microchip,sync-update-mask" corresponds to a PWM channel & represents
+ whether synchronous mode is possible for the PWM channel.
+
+ $ref: /schemas/types.yaml#/definitions/uint32
+ default: 0
+
+ microchip,dac-mode-mask:
+ description: |
+ Optional, per-channel Low Ripple DAC mode is possible on this IP core. It creates
+ a minimum period pulse train whose High/Low average is that of the chosen duty
+ cycle. This "DAC" will have far better bandwidth and ripple performance than the
+ standard PWM algorithm can achieve. A 16 bit DAC_MODE module parameter of the IP
+ core, set at instantiation and by the bitstream programmed to the FPGA, determines
+ whether a given channel operates in regular PWM or DAC mode.
+ Each bit corresponds to a PWM channel & represents whether DAC mode is enabled
+ for that channel.
+
+ $ref: /schemas/types.yaml#/definitions/uint32
+ default: 0
+
+required:
+ - compatible
+ - reg
+ - clocks
+
+additionalProperties: false
+
+examples:
+ - |
+ pwm@41000000 {
+ compatible = "microchip,corepwm-rtl-v4";
+ microchip,sync-update-mask = /bits/ 32 <0>;
+ clocks = <&clkcfg 30>;
+ reg = <0x41000000 0xF0>;
+ #pwm-cells = <2>;
+ };