On Thu, Sep 02, 2021 at 05:57:48PM -0500, Samuel Holland wrote: > On existing SoCs, the watchdog has a single clock input: HOSC (OSC24M) > divided by 750. However, starting with R329, LOSC (OSC32k) is added as > an alternative clock source, with a bit to switch between them. > > Since 24 MHz / 750 == 32 kHz, not 32.768 kHz, the hardware adjusts the > cycle counts to keep the timeouts independent of the clock source. This > keeps the programming interface backward-compatible. > > Furthermore, the R329 has two watchdogs: one for use by the ARM CPUs > at 0x20000a0, and a second one for use by the DSPs at 0x7020400. The > first of these adds two more new registers, to allow software to > immediately assert the SoC reset signal. Add an additional "-reset" > suffix to signify the presence of this feature. > > Signed-off-by: Samuel Holland <samuel@xxxxxxxxxxxx> > Acked-by: Maxime Ripard <maxime@xxxxxxxxxx> > Reviewed-by: Rob Herring <robh@xxxxxxxxxx> Acked-by: Guenter Roeck <linux@xxxxxxxxxxxx> > --- > Changes v2 to v3: > - Add else case > - Add additional allwinner,sun50i-r329-wdt-reset compatible > Changes v1 to v2: > - Switch clock-names from enum to const > - Add descriptions to "clocks" items > > .../watchdog/allwinner,sun4i-a10-wdt.yaml | 42 ++++++++++++++++++- > 1 file changed, 41 insertions(+), 1 deletion(-) > > diff --git a/Documentation/devicetree/bindings/watchdog/allwinner,sun4i-a10-wdt.yaml b/Documentation/devicetree/bindings/watchdog/allwinner,sun4i-a10-wdt.yaml > index 9aa3c313c49f..877f47759814 100644 > --- a/Documentation/devicetree/bindings/watchdog/allwinner,sun4i-a10-wdt.yaml > +++ b/Documentation/devicetree/bindings/watchdog/allwinner,sun4i-a10-wdt.yaml > @@ -24,6 +24,8 @@ properties: > - allwinner,sun50i-a100-wdt > - allwinner,sun50i-h6-wdt > - allwinner,sun50i-h616-wdt > + - allwinner,sun50i-r329-wdt > + - allwinner,sun50i-r329-wdt-reset > - const: allwinner,sun6i-a31-wdt > - items: > - const: allwinner,suniv-f1c100s-wdt > @@ -33,7 +35,18 @@ properties: > maxItems: 1 > > clocks: > - maxItems: 1 > + minItems: 1 > + maxItems: 2 > + items: > + - description: High-frequency oscillator input, divided internally > + - description: Low-frequency oscillator input, only found on some variants > + > + clock-names: > + minItems: 1 > + maxItems: 2 > + items: > + - const: hosc > + - const: losc > > interrupts: > maxItems: 1 > @@ -44,6 +57,33 @@ required: > - clocks > - interrupts > > +if: > + properties: > + compatible: > + contains: > + enum: > + - allwinner,sun50i-r329-wdt > + - allwinner,sun50i-r329-wdt-reset > + > +then: > + properties: > + clocks: > + minItems: 2 > + > + clock-names: > + minItems: 2 > + > + required: > + - clock-names > + > +else: > + properties: > + clocks: > + maxItems: 1 > + > + clock-names: > + maxItems: 1 > + > unevaluatedProperties: false > > examples:
