Re: [linux-sunxi] [PATCH v4 4/5] ARM: sunxi: h3/h5: switch apb0-related clocks to r_ccu

From: icenowy
Date: Thu Jul 20 2017 - 04:24:45 EST


å 2017-07-20 06:59ïOndÅej Jirman åéï
Hi,

Icenowy Zheng pÃÅe v Ãt 04. 04. 2017 v 17:50 +0800:
From: Icenowy Zheng <icenowy@xxxxxxxx>

Now we have driver for the PRCM CCU, switch to use it instead of
old-style clock nodes for apb0-related clocks in sunxi-h3-h5.dtsi .

The mux 3 of R_CCU is still the internal oscillator, which is said to be
16MHz plus minus 30%, and get a measured value of 15MHz~16MHz on my two
H3 boards and one H5 board.

There's issue with the new r_ccu that breaks r_i2c. (no devices can be
found on the bus). Reverting this patch fixes the issue with the I2C
controller. (everything else being the same)

Here's the code I'm using: https://github.com/megous/linux/commits/oran
ge-pi-4.12

The last commit is the revert.

The issue manifests itself by non-working DVFS, because kernel lacks
access to SY8106A regulator, because r_i2c doesn't work with sunxi-ng
clock driver (sun8i-r).

Relevant difference in registers between working/non-working state is
just this (diff -u):

0x01f02400 = 0x00000000
0x01f02404 = 0x00000000
-0x01f02408 = 0x00000091
+0x01f02408 = 0x00000095 DATA register inisde the I2C controller
0x01f0240c = 0x00000044
0x01f02410 = 0x000000f8
-0x01f02414 = 0x00000059
+0x01f02414 = 0x00000000 CLOCK setup register inside the I2C controller
0x01f02418 = 0x00000000
0x01f0241c = 0x00000000
0x01f02420 = 0x0000003a

It looks like the new sunxi-ng clock driver causes the I2C driver to
not correctly configure the CLOCK register. I don't know why and I'm
not sure how to deal with this. Any ideas what can I do next?

Could you apply the patches at [1] and [2] to U-Boot and re-try with
r_ccu? They switched the CPUs clock of r_ccu to non-secure mode, which
makes it possible to be accessed from the kernel running in non-secure.

I think these patches can solve this problem.

[1] https://patchwork.ozlabs.org/patch/791414/
[2] https://patchwork.ozlabs.org/patch/791415/


thank you and regards,
o.

Signed-off-by: Icenowy Zheng <icenowy@xxxxxxxx>
---
Changes in v4:
- Temporarily dropped the CCU headers.
Changes in v3:
- Change osc32000 to iosc.

arch/arm/boot/dts/sunxi-h3-h5.dtsi | 45 ++++++++++++--------------------------
1 file changed, 14 insertions(+), 31 deletions(-)

diff --git a/arch/arm/boot/dts/sunxi-h3-h5.dtsi b/arch/arm/boot/dts/sunxi-h3-h5.dtsi
index 6640ebfa6419..1aeeacb3a884 100644
--- a/arch/arm/boot/dts/sunxi-h3-h5.dtsi
+++ b/arch/arm/boot/dts/sunxi-h3-h5.dtsi
@@ -68,31 +68,12 @@
clock-output-names = "osc32k";
};

- apb0: apb0_clk {
- compatible = "fixed-factor-clock";
+ iosc: internal-osc-clk {
#clock-cells = <0>;
- clock-div = <1>;
- clock-mult = <1>;
- clocks = <&osc24M>;
- clock-output-names = "apb0";
- };
-
- apb0_gates: clk@01f01428 {
- compatible = "allwinner,sun8i-h3-apb0-gates-clk",
- "allwinner,sun4i-a10-gates-clk";
- reg = <0x01f01428 0x4>;
- #clock-cells = <1>;
- clocks = <&apb0>;
- clock-indices = <0>, <1>;
- clock-output-names = "apb0_pio", "apb0_ir";
- };
-
- ir_clk: ir_clk@01f01454 {
- compatible = "allwinner,sun4i-a10-mod0-clk";
- reg = <0x01f01454 0x4>;
- #clock-cells = <0>;
- clocks = <&osc32k>, <&osc24M>;
- clock-output-names = "ir";
+ compatible = "fixed-clock";
+ clock-frequency = <16000000>;
+ clock-accuracy = <300000000>;
+ clock-output-names = "iosc";
};
};

@@ -576,9 +557,12 @@
<GIC_SPI 41 IRQ_TYPE_LEVEL_HIGH>;
};

- apb0_reset: reset@01f014b0 {
- reg = <0x01f014b0 0x4>;
- compatible = "allwinner,sun6i-a31-clock-reset";
+ r_ccu: clock@1f01400 {
+ compatible = "allwinner,sun50i-a64-r-ccu";
+ reg = <0x01f01400 0x100>;
+ clocks = <&osc24M>, <&osc32k>, <&iosc>;
+ clock-names = "hosc", "losc", "iosc";
+ #clock-cells = <1>;
#reset-cells = <1>;
};

@@ -589,9 +573,9 @@

ir: ir@01f02000 {
compatible = "allwinner,sun5i-a13-ir";
- clocks = <&apb0_gates 1>, <&ir_clk>;
+ clocks = <&r_ccu 4>, <&r_ccu 11>;
clock-names = "apb", "ir";
- resets = <&apb0_reset 1>;
+ resets = <&r_ccu 0>;
interrupts = <GIC_SPI 37 IRQ_TYPE_LEVEL_HIGH>;
reg = <0x01f02000 0x40>;
status = "disabled";
@@ -601,9 +585,8 @@
compatible = "allwinner,sun8i-h3-r-pinctrl";
reg = <0x01f02c00 0x400>;
interrupts = <GIC_SPI 45 IRQ_TYPE_LEVEL_HIGH>;
- clocks = <&apb0_gates 0>, <&osc24M>, <&osc32k>;
+ clocks = <&r_ccu 3>, <&osc24M>, <&osc32k>;
clock-names = "apb", "hosc", "losc";
- resets = <&apb0_reset 0>;
gpio-controller;
#gpio-cells = <3>;
interrupt-controller;
--
2.12.2

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