dt-bindings: clock: u8500: Rewrite in YAML and extend

This rewrites the ux500/u8500 clock bindings in YAML schema and extends them
with the PRCC reset controller.

The bindings are a bit idiomatic but it just reflects their age, the ux500
platform was used as guinea pig for early device tree conversion of platforms
in 2015. The new subnode for the reset controller follows the pattern of the
old bindings and adds a node with reset-cells for this.

Cc: devicetree@vger.kernel.org
Cc: Philipp Zabel <p.zabel@pengutronix.de>
Reviewed-by: Rob Herring <robh@kernel.org>
Acked-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Link: https://lore.kernel.org/r/20210921184803.1757916-1-linus.walleij@linaro.org
Signed-off-by: Stephen Boyd <sboyd@kernel.org>

1 files changed, 121 insertions, 0 deletions

diff --git a/Documentation/devicetree/bindings/clock/stericsson,u8500-clks.yaml b/Documentation/devicetree/bindings/clock/stericsson,u8500-clks.yaml
new file mode 100644
index 000000000000..9bc95a308477
--- /dev/null
+++ b/Documentation/devicetree/bindings/clock/stericsson,u8500-clks.yaml
@@ -0,0 +1,121 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/clock/stericsson,u8500-clks.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: ST-Ericsson DB8500 (U8500) clocks
+
+maintainers:
+  - Ulf Hansson <ulf.hansson@linaro.org>
+  - Linus Walleij <linus.walleij@linaro.org>
+
+description: While named "U8500 clocks" these clocks are inside the
+  DB8500 digital baseband system-on-chip and its siblings such as
+  DB8520. These bindings consider the clocks present in the SoC
+  itself, not off-chip clocks. There are four different on-chip
+  clocks - RTC (32 kHz), CPU clock (SMP TWD), PRCMU (power reset and
+  control management unit) clocks and PRCC (peripheral reset and
+  clock controller) clocks. For some reason PRCC 4 does not exist so
+  the itemization can be a bit unintuitive.
+
+properties:
+  compatible:
+    enum:
+      - stericsson,u8500-clks
+      - stericsson,u8540-clks
+      - stericsson,u9540-clks
+
+  reg:
+    items:
+      - description: PRCC 1 register area
+      - description: PRCC 2 register area
+      - description: PRCC 3 register area
+      - description: PRCC 5 register area
+      - description: PRCC 6 register area
+
+  prcmu-clock:
+    description: A subnode with one clock cell for PRCMU (power, reset, control
+      management unit) clocks. The cell indicates which PRCMU clock in the
+      prcmu-clock node the consumer wants to use.
+    type: object
+
+    properties:
+      '#clock-cells':
+        const: 1
+
+    additionalProperties: false
+
+  prcc-periph-clock:
+    description: A subnode with two clock cells for PRCC (peripheral
+      reset and clock controller) peripheral clocks. The first cell indicates
+      which PRCC block the consumer wants to use, possible values are 1, 2, 3,
+      5, 6. The second cell indicates which clock inside the PRCC block it
+      wants, possible values are 0 thru 31.
+    type: object
+
+    properties:
+      '#clock-cells':
+        const: 2
+
+    additionalProperties: false
+
+  prcc-kernel-clock:
+    description: A subnode with two clock cells for PRCC (peripheral reset
+      and clock controller) kernel clocks. The first cell indicates which PRCC
+      block the consumer wants to use, possible values are 1, 2, 3, 5, 6. The
+      second cell indicates which clock inside the PRCC block it wants, possible
+      values are 0 thru 31.
+    type: object
+
+    properties:
+      '#clock-cells':
+        const: 2
+
+    additionalProperties: false
+
+  prcc-reset-controller:
+    description: A subnode with two reset cells for the reset portions of the
+      PRCC (peripheral reset and clock controller). The first cell indicates
+      which PRCC block the consumer wants to use, possible values are 1, 2, 3
+      5 and 6. The second cell indicates which reset line inside the PRCC block
+      it wants to control, possible values are 0 thru 31.
+    type: object
+
+    properties:
+      '#reset-cells':
+        const: 2
+
+    additionalProperties: false
+
+  rtc32k-clock:
+    description: A subnode with zero clock cells for the 32kHz RTC clock.
+    type: object
+
+    properties:
+      '#clock-cells':
+        const: 0
+
+    additionalProperties: false
+
+  smp-twd-clock:
+    description: A subnode for the ARM SMP Timer Watchdog cluster with zero
+      clock cells.
+    type: object
+
+    properties:
+      '#clock-cells':
+        const: 0
+
+    additionalProperties: false
+
+required:
+  - compatible
+  - reg
+  - prcmu-clock
+  - prcc-periph-clock
+  - prcc-kernel-clock
+  - rtc32k-clock
+  - smp-twd-clock
+
+additionalProperties: false