[OpenWrt-Devel] [PATCH] staging: mt7621-dts: correct various clock frequencies.

[Rosen Penev]

From: NeilBrown <neil at brown.name>

The MT7621 documentation says that the sys clock - also known
as OCP clock for the Open Core Protocol - can be configured to
1/3 or 1/4 of the CPU clock.
Testing on my hardware, using the fact that the SPI clock is
based on the OCP clock and measuring transfer rates, shows
a clock of a little over 200MHz with a CPU clock of 900MHz.
So assume 1/4 is the default.

Also, the nor-flash in the gbpc1 is documented as accepting 50MHz
for request requests, and higher for other requests.  So set
maximum to 50MHz.

Signed-off-by: NeilBrown <neil at brown.name>
Signed-off-by: Greg Kroah-Hartman <gregkh at linuxfoundation.org>
---
 target/linux/ramips/dts/GB-PC1.dts  | 8 +++++++-
 target/linux/ramips/dts/mt7621.dtsi | 4 ++--
 2 files changed, 9 insertions(+), 3 deletions(-)

diff --git a/target/linux/ramips/dts/GB-PC1.dts b/target/linux/ramips/dts/GB-PC1.dts
index 3b29d335b9..db6c3a86b0 100644
--- a/target/linux/ramips/dts/GB-PC1.dts
+++ b/target/linux/ramips/dts/GB-PC1.dts
@@ -71,7 +71,7 @@
 		#size-cells = <1>;
 		compatible = "jedec,spi-nor";
 		reg = <0>;
-		spi-max-frequency = <10000000>;
+		spi-max-frequency = <50000000>;
 		m25p,chunked-io = <32>;
 
 		partition at 0 {
@@ -99,6 +99,12 @@
 	};
 };
 
+&sysclock {
+	compatible = "fixed-clock";
+	/* This is normally 1/4 of cpuclock */
+	clock-frequency = <225000000>;
+};
+
 &cpuclock {
 	compatible = "fixed-clock";
 	clock-frequency = <900000000>;
diff --git a/target/linux/ramips/dts/mt7621.dtsi b/target/linux/ramips/dts/mt7621.dtsi
index 0655e35301..dd8e87f7ce 100644
--- a/target/linux/ramips/dts/mt7621.dtsi
+++ b/target/linux/ramips/dts/mt7621.dtsi
@@ -45,8 +45,8 @@
 		#clock-cells = <0>;
 		compatible = "fixed-clock";
 
-		/* FIXME: there should be way to detect this */
-		clock-frequency = <50000000>;
+		/* This is normally 1/4 of cpuclock */
+		clock-frequency = <220000000>;
 	};
 
 
-- 
2.17.1


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