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* [PATCH v2] ARM: dts: lpc32xx: Revert set default clock rate of HCLK PLL
@ 2019-10-10 20:57 Alexandre Belloni
  0 siblings, 0 replies; only message in thread
From: Alexandre Belloni @ 2019-10-10 20:57 UTC (permalink / raw)
  To: Vladimir Zapolskiy
  Cc: Sylvain Lemieux, linux-arm-kernel, linux-kernel,
	Alexandre Belloni, Gregory CLEMENT

This reverts commit c17e9377aa81664d94b4f2102559fcf2a01ec8e7.

The lpc32xx clock driver is not able to actually change the PLL rate as
this would require reparenting ARM_CLK, DDRAM_CLK, PERIPH_CLK to SYSCLK,
then stop the PLL, update the register, restart the PLL and wait for the
PLL to lock and finally reparent ARM_CLK, DDRAM_CLK, PERIPH_CLK to HCLK
PLL.

Currently, the HCLK driver simply updates the registers but this has no
real effect and all the clock rate calculation end up being wrong. This is
especially annoying for the peripheral (e.g. UARTs, I2C, SPI).

Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Tested-by: Gregory CLEMENT <gregory.clement@bootlin.com>
---

Changes in v2:
  - rebase on v5.4-rc1
  - collected tested-by

 arch/arm/boot/dts/lpc32xx.dtsi | 3 ---
 1 file changed, 3 deletions(-)

diff --git a/arch/arm/boot/dts/lpc32xx.dtsi b/arch/arm/boot/dts/lpc32xx.dtsi
index a9a016620468..2508e9a3250a 100644
--- a/arch/arm/boot/dts/lpc32xx.dtsi
+++ b/arch/arm/boot/dts/lpc32xx.dtsi
@@ -329,9 +329,6 @@
 
 					clocks = <&xtal_32k>, <&xtal>;
 					clock-names = "xtal_32k", "xtal";
-
-					assigned-clocks = <&clk LPC32XX_CLK_HCLK_PLL>;
-					assigned-clock-rates = <208000000>;
 				};
 			};
 
-- 
2.21.0


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