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ARM: dts: koelsch: Correct clock frequency of X2 DU clock input

PATCH New Geert Uytterhoeven 5 participants 5 messages Apr 3, 2017 – Apr 4, 2017 Device tree bindings

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Geert Uytterhoeven

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#0 lore raw

PATCH 1/1 ARM: dts: koelsch: Correct clock frequency of X2 DU clock input

The X2 crystal oscillator on the Koelsch development board provides a 74.25 MHz clock, not a 148.5 MHz clock.

Fixes cd21cb46e14aae3a ("ARM: shmobile: koelsch: Add DU external pixel clocks to DT")
Signed-off-by Geert Uytterhoeven <[email protected]>

---
Confirmed by schematics, user manual, and physical inspection of 2 Koelsch instances (my scope has not enough bandwidth to measure the actual frequency).

Probably this was copied from r8a7790-lager.dts, as Lager does have two identical crystal oscillators X2 and X13.

Note that X2 is socketed, so it can be changed.

---
 arch/arm/boot/dts/r8a7791-koelsch.dts | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
arch/arm/boot/dts/r8a7791-koelsch.dts +1 -1
index 59beb8402a36007b..001e6116c47c7c3b 100644
@@ -292,7 +292,7 @@
 	x2_clk: x2-clock {
 		compatible = "fixed-clock";
 		#clock-cells = <0>;
-		clock-frequency = <148500000>;
+		clock-frequency = <74250000>;
 	};
 
 	x13_clk: x13-clock {
Signature · 1 line
2.7.4
#1 lore raw

PATCH 1/1 ARM: dts: koelsch: Correct clock frequency of X2 DU clock input

Quoted 10 lines · Geert Uytterhoeven

The X2 crystal oscillator on the Koelsch development board provides a 74.25 MHz clock, not a 148.5 MHz clock.

Fixes cd21cb46e14aae3a ("ARM: shmobile: koelsch: Add DU external pixel clocks to DT")
Signed-off-by Geert Uytterhoeven <[email protected]>

---
Confirmed by schematics, user manual, and physical inspection of 2 Koelsch instances (my scope has not enough bandwidth to measure the actual frequency).

Quoted 4 lines

Probably this was copied from r8a7790-lager.dts, as Lager does have two identical crystal oscillators X2 and X13.

Note that X2 is socketed, so it can be changed.

Thanks, I have queued this up.

#2 lore raw

PATCH 1/1 ARM: dts: koelsch: Correct clock frequency of X2 DU clock input

In reply to Geert Uytterhoeven

Hi Geert,

Thank you for the patch.

Quoted 9 lines · On Monday 03 Apr 2017 11:55:19 Geert Uytterhoeven wrote:

The X2 crystal oscillator on the Koelsch development board provides a 74.25 MHz clock, not a 148.5 MHz clock.

Fixes cd21cb46e14aae3a ("ARM: shmobile: koelsch: Add DU external pixel

clocks to DT") Signed-off-by: Geert Uytterhoeven <[email protected]>
---
Confirmed by schematics, user manual, and physical inspection of 2 Koelsch instances (my scope has not enough bandwidth to measure the actual frequency).

Stupid question, have you tested the corresponding (HDMI) DU output ? If so,

Acked-by Laurent Pinchart <[email protected]>
Quoted 22 lines

Probably this was copied from r8a7790-lager.dts, as Lager does have two identical crystal oscillators X2 and X13.

Note that X2 is socketed, so it can be changed.

---
 arch/arm/boot/dts/r8a7791-koelsch.dts | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
(quoted diff) +0 -0

b/arch/arm/boot/dts/r8a7791-koelsch.dts index
59beb8402a36007b..001e6116c47c7c3b 100644

arch/arm/boot/dts/r8a7791-koelsch.dts +1 -1
@@ -292,7 +292,7 @@
 	x2_clk: x2-clock {
 		compatible = "fixed-clock";
 		#clock-cells = <0>;
-		clock-frequency = <148500000>;
+		clock-frequency = <74250000>;
 	};
 
 	x13_clk: x13-clock {
Signature · 3 lines
Regards,

Laurent Pinchart
#3 lore raw

PATCH 1/1 ARM: dts: koelsch: Correct clock frequency of X2 DU clock input

Hi Laurent,

Quoted 4 lines · Laurent Pinchart
Quoted 3 lines · On Monday 03 Apr 2017 11:55:19 Geert Uytterhoeven wrote:

The X2 crystal oscillator on the Koelsch development board provides a 74.25 MHz clock, not a 148.5 MHz clock.

Quoted 8 lines
Quoted 6 lines
Fixes cd21cb46e14aae3a ("ARM: shmobile: koelsch: Add DU external pixel

clocks to DT") Signed-off-by: Geert Uytterhoeven <[email protected]>
---
Confirmed by schematics, user manual, and physical inspection of 2 Koelsch instances (my scope has not enough bandwidth to measure the actual frequency).

Stupid question, have you tested the corresponding (HDMI) DU output ? If so,

No I haven't.

Niklas, can you please fire up your display? Thanks!

Quoted 1 line
Acked-by Laurent Pinchart <[email protected]>

Thanks ;-)

Gr{oetje,eeting}s,

Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert at linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But when I'm talking to journalists I just say "programmer" or something like that.
-- Linus Torvalds

#4 lore raw

PATCH 1/1 ARM: dts: koelsch: Correct clock frequency of X2 DU clock input

Hi Geert,

Quoted 15 lines · Geert Uytterhoeven

Hi Laurent,

Quoted 11 lines · Laurent Pinchart
Quoted 9 lines · On Monday 03 Apr 2017 11:55:19 Geert Uytterhoeven wrote:

The X2 crystal oscillator on the Koelsch development board provides a 74.25 MHz clock, not a 148.5 MHz clock.

Fixes cd21cb46e14aae3a ("ARM: shmobile: koelsch: Add DU external pixel

clocks to DT") Signed-off-by: Geert Uytterhoeven <[email protected]>
---
Confirmed by schematics, user manual, and physical inspection of 2 Koelsch instances (my scope has not enough bandwidth to measure the actual frequency).

Quoted 5 lines
Quoted 1 line

Stupid question, have you tested the corresponding (HDMI) DU output ? If so,

No I haven't.

Niklas, can you please fire up your display? Thanks!

Console during boot works and

modetest -M rcar-du -s 46:1920x1080-60Hz
modetest -M rcar-du -s 46:1280x720-60Hz
modetest -M rcar-du -s 46:720x480-60Hz

Produce stable test patterns.

Tested-by Niklas S?derlund <[email protected]>
Quoted 15 lines
Quoted 2 lines
Acked-by Laurent Pinchart <[email protected]>

Thanks ;-)

Gr{oetje,eeting}s,

Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert at linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But when I'm talking to journalists I just say "programmer" or something like that.
-- Linus Torvalds

Signature · 2 lines
Regards,
Niklas S?derlund