Re: [PATCH] clk: rockchip: mark pclk_uart2 as critical on rk3328

elaine.zhang
2020-07-10T01:29:02Z

在 2020/7/9 下午8:04, Johan Jonker 写道:
> Hi Elaine, Robin,
>
> Thank you for your help!
> This patch can go in the garbage bin.
> It turns out that with SERIAL_8250 also SERIAL_8250_DW must be
> selected... ;)
>
> It's not in the Kconfig help description.
> Shouldn't that be automatically be included for Rockchip?
> Example:
>
> config SERIAL_8250
> tristate "8250/16550 and compatible serial support"
> depends on !S390
> select SERIAL_CORE
> select SERIAL_MCTRL_GPIO if GPIOLIB
> select SERIAL_8250_DW if ARCH_ROCKCHIP

Our  Konfig:

config SERIAL_8250
tristate "8250/16550 and compatible serial support"
depends on !S390
select SERIAL_CORE

config SERIAL_8250_DW
tristate "Support for Synopsys DesignWare 8250 quirks"
depends on SERIAL_8250

So SERIAL_8250 and SERIAL_8250_DW must be selected.

If you use select SERIAL_8250_DW if ARCH_ROCKCHIP, check the CONIF_ARCH_ROCKCHIP=y.
In our rockchip_defconfig the CONIF_ARCH_ROCKCHIP=y by default.

> Thank Robin for the introduction to FTRACE!
>
> mount -t tracefs tracefs /sys/kernel/tracing
>
> cd /sys/kernel/tracing
>
> # Without SERIAL_8250_DW
>
> /sys/kernel/tracing # cat trace | grep uart2
> <idle>-0 [000] d..2 0.000000: clk_enable: clk_uart2_div
> <idle>-0 [000] d..2 0.000000: clk_enable: clk_uart2_frac
> <idle>-0 [000] d..2 0.000000: clk_disable: clk_uart2_frac
> <idle>-0 [000] d..2 0.000000: clk_disable: clk_uart2_div
> swapper/0-1 [002] d..1 1.916746: clk_disable: pclk_uart2
>
>
> /sys/kernel/tracing # cat trace | grep uart
> <idle>-0 [000] d..2 0.000000: clk_enable: clk_uart2_div
> <idle>-0 [000] d..2 0.000000: clk_enable: clk_uart2_frac
> <idle>-0 [000] d..2 0.000000: clk_disable: clk_uart2_frac
> <idle>-0 [000] d..2 0.000000: clk_disable: clk_uart2_div
> <idle>-0 [000] d..2 0.000000: clk_enable: clk_uart1_div
> <idle>-0 [000] d..2 0.000000: clk_enable: clk_uart1_frac
> <idle>-0 [000] d..2 0.000000: clk_disable: clk_uart1_frac
> <idle>-0 [000] d..2 0.000000: clk_disable: clk_uart1_div
> <idle>-0 [000] d..2 0.000000: clk_enable: clk_uart0_div
> <idle>-0 [000] d..2 0.000000: clk_enable: clk_uart0_frac
> <idle>-0 [000] d..2 0.000000: clk_disable: clk_uart0_frac
> <idle>-0 [000] d..2 0.000000: clk_disable: clk_uart0_div
> swapper/0-1 [002] d..1 1.916746: clk_disable: pclk_uart2
> swapper/0-1 [002] d..1 1.923959: clk_disable: pclk_uart1
> swapper/0-1 [002] d..1 1.930741: clk_disable: pclk_uart0
>
> # With SERIAL_8250_DW
>
> /sys/kernel/tracing # cat trace | grep uart2
> <idle>-0 [000] d..2 0.000000: clk_enable: clk_uart2_div
> <idle>-0 [000] d..2 0.000000: clk_enable: clk_uart2_frac
> <idle>-0 [000] d..2 0.000000: clk_disable: clk_uart2_frac
> <idle>-0 [000] d..2 0.000000: clk_disable: clk_uart2_div
> swapper/0-1 [002] d..1 0.923180: clk_enable: sclk_uart2
> swapper/0-1 [002] d..1 0.923224: clk_enable: pclk_uart2
> swapper/0-1 [002] d..1 0.925259: clk_disable: sclk_uart2
> swapper/0-1 [002] d..1 0.925295: clk_enable: sclk_uart2
> swapper/0-1 [003] d..1 2.208605: clk_disable: sclk_uart2
> swapper/0-1 [003] d..1 2.208646: clk_enable: sclk_uart2
>
> /sys/kernel/tracing # cat trace | grep uart
> <idle>-0 [000] d..2 0.000000: clk_enable: clk_uart2_div
> <idle>-0 [000] d..2 0.000000: clk_enable: clk_uart2_frac
> <idle>-0 [000] d..2 0.000000: clk_disable: clk_uart2_frac
> <idle>-0 [000] d..2 0.000000: clk_disable: clk_uart2_div
> <idle>-0 [000] d..2 0.000000: clk_enable: clk_uart1_div
> <idle>-0 [000] d..2 0.000000: clk_enable: clk_uart1_frac
> <idle>-0 [000] d..2 0.000000: clk_disable: clk_uart1_frac
> <idle>-0 [000] d..2 0.000000: clk_disable: clk_uart1_div
> <idle>-0 [000] d..2 0.000000: clk_enable: clk_uart0_div
> <idle>-0 [000] d..2 0.000000: clk_enable: clk_uart0_frac
> <idle>-0 [000] d..2 0.000000: clk_disable: clk_uart0_frac
> <idle>-0 [000] d..2 0.000000: clk_disable: clk_uart0_div
> swapper/0-1 [002] d..1 0.920034: clk_enable: sclk_uart0
> swapper/0-1 [002] d..1 0.920085: clk_enable: pclk_uart0
> kworker/2:1-32 [002] d..1 0.922596: clk_disable: sclk_uart0
> kworker/2:1-32 [002] d..1 0.922613: clk_disable: pclk_uart0
> swapper/0-1 [002] d..1 0.923180: clk_enable: sclk_uart2
> swapper/0-1 [002] d..1 0.923224: clk_enable: pclk_uart2
> swapper/0-1 [002] d..1 0.925259: clk_disable: sclk_uart2
> swapper/0-1 [002] d..1 0.925295: clk_enable: sclk_uart2
> swapper/0-1 [003] d..1 1.914158: clk_disable: pclk_uart1
> swapper/0-1 [003] d..1 2.208605: clk_disable: sclk_uart2
> swapper/0-1 [003] d..1 2.208646: clk_enable: sclk_uart2
>
>
>
> On 7/9/20 3:32 AM, elaine.zhang wrote:
>> 在 2020/7/8 下午10:45, Johan Jonker 写道:
>>> The rk3328 uart2 port is used as boot console and to debug.
>>> During the boot pclk_uart2 is disabled by a clk_disable_unused
>>> initcall. Fix the uart2 function by marking pclk_uart2
>>> as critical on rk3328. Also add sclk_uart2 as that is needed
>>> for the same DT node.
>>>
>>> Signed-off-by: Johan Jonker <jbx6244@gmail.com>
>>> ---
>>>   drivers/clk/rockchip/clk-rk3328.c | 2 ++
>>>   1 file changed, 2 insertions(+)
>>>
>>> diff --git a/drivers/clk/rockchip/clk-rk3328.c
>>> b/drivers/clk/rockchip/clk-rk3328.c
>>> index c186a1985..cb7749cb7 100644
>>> --- a/drivers/clk/rockchip/clk-rk3328.c
>>> +++ b/drivers/clk/rockchip/clk-rk3328.c
>>> @@ -875,6 +875,8 @@ static const char *const rk3328_critical_clocks[]
>>> __initconst = {
>>>       "aclk_gmac_niu",
>>>       "pclk_gmac_niu",
>>>       "pclk_phy_niu",
>>> +    "pclk_uart2",
>>> +    "sclk_uart2",
>>>   };
>>>
>> Not need to mark the uart2 as critical clocks, the uart clk will enabled
>> by uart driver probe(dw8250_probe()).
>>
>> For your question,  Please check the uart2 dts node "status = okay".
>>
>> Or You can send me the complete log, I check the status of uart2.
>>
>>>   static void __init rk3328_clk_init(struct device_node *np)
>>
>
>
>