[PATCH v2] ARM: dts: microchip: sam9x60: Fix rtc/rtt clocks

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The RTC and RTT peripherals use the "timing domain slow clock (TD_SLCK),
sourced from the 32.768 kHz crystal oscillator.

(The previously used Monitoring domain slow clock (MD_SLCK) is sourced
from an internal RC oscillator which is most probably not precise enough
for real time clock purposes.)

Fixes: 1e5f532c2737 ("ARM: dts: at91: sam9x60: add device tree for soc and board")
Fixes: 5f6b33f46346 ("ARM: dts: sam9x60: add rtt")
Signed-off-by: Alexander Dahl <ada@xxxxxxxxxxx>
---

Notes:
    Picked the wrong patch in the first try.  This v2 one has a slightly
    adapted commit message and more context below.
    
    This obviously requires a 32.768 kHz crystal oscillator to be present,
    but the sam9x60.dtsi does contain that, and the clock-controllers
    reference that, so I assume it's always present.
    
    /sys/kernel/debug/clk/clk_summary content excerpt before:
    
         slow_rc_osc                         1       1        0        32768       93750000   0     50000      Y   deviceless                      no_connection_id
            md_slck                          4       4        0        32768       0          0     50000      Y      fffffea8.rtc                    no_connection_id
                                                                                                                      fffffe20.rtc                    no_connection_id
                                                                                                                      fffffe10.poweroff               no_connection_id
                                                                                                                      fffffe00.reset-controller       no_connection_id
                                                                                                                      timer@f8008000                  slow_clk
                                                                                                                      deviceless                      no_connection_id
    …
         slow_xtal                           0       0        0        32768       0          0     50000      Y   deviceless                      no_connection_id
            slow_osc                         0       0        0        32768       0          0     50000      Y      deviceless                      no_connection_id
               td_slck                       0       0        0        32768       0          0     50000      Y         deviceless                      no_connection_id
    
    And after:
    
         slow_rc_osc                         1       1        0        32768       93750000   0     50000      Y   deviceless                      no_connection_id
            md_slck                          2       2        0        32768       0          0     50000      Y      fffffe10.poweroff               no_connection_id
                                                                                                                      fffffe00.reset-controller       no_connection_id
                                                                                                                      timer@f8008000                  slow_clk
                                                                                                                      deviceless                      no_connection_id
    …
         slow_xtal                           1       1        0        32768       0          0     50000      Y   deviceless                      no_connection_id
            slow_osc                         1       1        0        32768       0          0     50000      Y      deviceless                      no_connection_id
               td_slck                       2       2        0        32768       0          0     50000      Y         fffffea8.rtc                    no_connection_id
                                                                                                                         fffffe20.rtc                    no_connection_id
                                                                                                                         deviceless                      no_connection_id

 arch/arm/boot/dts/microchip/sam9x60.dtsi | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/arch/arm/boot/dts/microchip/sam9x60.dtsi b/arch/arm/boot/dts/microchip/sam9x60.dtsi
index 291540e5d81e..d077afd5024d 100644
--- a/arch/arm/boot/dts/microchip/sam9x60.dtsi
+++ b/arch/arm/boot/dts/microchip/sam9x60.dtsi
@@ -1312,7 +1312,7 @@ rtt: rtc@fffffe20 {
 				compatible = "microchip,sam9x60-rtt", "atmel,at91sam9260-rtt";
 				reg = <0xfffffe20 0x20>;
 				interrupts = <1 IRQ_TYPE_LEVEL_HIGH 7>;
-				clocks = <&clk32k 0>;
+				clocks = <&clk32k 1>;
 			};
 
 			pit: timer@fffffe40 {
@@ -1338,7 +1338,7 @@ rtc: rtc@fffffea8 {
 				compatible = "microchip,sam9x60-rtc", "atmel,at91sam9x5-rtc";
 				reg = <0xfffffea8 0x100>;
 				interrupts = <1 IRQ_TYPE_LEVEL_HIGH 7>;
-				clocks = <&clk32k 0>;
+				clocks = <&clk32k 1>;
 			};
 
 			watchdog: watchdog@ffffff80 {

base-commit: 47ac09b91befbb6a235ab620c32af719f8208399
-- 
2.39.2





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