2017-01-13 20:25 GMT+01:00 David Lechner <david@xxxxxxxxxxxxxx>: > On 01/13/2017 06:37 AM, Bartosz Golaszewski wrote: >> >> Add DT bindings for the TI DA850 AHCI SATA controller. >> >> Signed-off-by: Bartosz Golaszewski <bgolaszewski@xxxxxxxxxxxx> >> --- >> .../devicetree/bindings/ata/ahci-da850.txt | 21 >> +++++++++++++++++++++ >> 1 file changed, 21 insertions(+) >> create mode 100644 Documentation/devicetree/bindings/ata/ahci-da850.txt >> >> diff --git a/Documentation/devicetree/bindings/ata/ahci-da850.txt >> b/Documentation/devicetree/bindings/ata/ahci-da850.txt >> new file mode 100644 >> index 0000000..d07c241 >> --- /dev/null >> +++ b/Documentation/devicetree/bindings/ata/ahci-da850.txt >> @@ -0,0 +1,21 @@ >> +Device tree binding for the TI DA850 AHCI SATA Controller >> +--------------------------------------------------------- >> + >> +Required properties: >> + - compatible: must be "ti,da850-ahci" >> + - reg: physical base addresses and sizes of the controller's register >> areas >> + - interrupts: interrupt specifier (refer to the interrupt binding) >> + >> +Optional properties: >> + - clocks: clock specifier (refer to the common clock binding) >> + - da850,clk_multiplier: the multiplier for the reference clock needed >> + for 1.5GHz PLL output > > > A clock multiplier property seems redundant if you are specifying a clock. > It should be possible to get the rate from the clock to determine which > multiplier is needed. > I probably should have named it differently. This is not a multiplier of a clock derived from PLL0 or PLL1. Instead it's a value set by writing to the Port PHY Control Register (MPY bits) of the SATA controller that configures the multiplier for the external low-jitter clock. On the lcdk the signals (REFCLKP, REFCLKN) are provided by CDCM61001 (SATA OSCILLATOR component on the schematics). I'll find a better name and comment the property accordingly. FYI: the da850 platform does not use the common clock framework, so I don't specify the clock property on the sata node in the device tree. Instead I add the clock lookup entry in patch [01/10]. This is transparent for AHCI which can get the clock as usual by calling clk_get() in ahci_platform_get_resources(). Thanks, Bartosz Golaszewski -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
