[linux-sunxi] [PATCH v4 4/5] ARM: sunxi: h3/h5: switch apb0-related clocks to r_ccu
icenowy at aosc.io
icenowy at aosc.io
Wed Jul 19 22:15:15 PDT 2017
在 2017-07-20 10:03，icenowy at aosc.io 写道：
> 在 2017-07-20 06:59，Ondřej Jirman 写道：
>> Hi,
>>
>> Icenowy Zheng píše v Út 04. 04. 2017 v 17:50 +0800:
>>> From: Icenowy Zheng <icenowy at aosc.xyz>
>>>
>>> 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?
>>
>> thank you and regards,
>> o.
>
> It seems to be a very very very weird problem -- the CPUS_CFG register
> seems to be not accessible in non-secure mode on H3, and if the r_ccu
> driver reads it a value of 0x0 is read out (which means that the parent
> of ar100 is osc32k), but the real initial value of the register is
> 0x00010000 (which means the parent is osc24M).
>
> So the bus clock of r_i2c is wrongly claimed as 32kHz, not 24MHz, then
> the r_i2c fails to work.
The protection to AR100 registers can be removed by writing 1 to
0x01f015d0
(0x1d0 at PRCM memory region).
Interestingly this controlling register can be written in non-secure
world,
so it's still broken secure/non-secure division ;-)
>
> This clock problem doesn't exist for A64.
>
>>
>>> Signed-off-by: Icenowy Zheng <icenowy at aosc.xyz>
>>> ---
>>> 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 at 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 at 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 at 01f014b0 {
>>> - reg = <0x01f014b0 0x4>;
>>> - compatible = "allwinner,sun6i-a31-clock-reset";
>>> + r_ccu: clock at 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 at 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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