Re: [PATCH v7 6/7] clk: hi6220: Clock driver support for Hisilicon hi6220 SoC

[Bintian <bintian.wang@huawei.com>]

Hello Stephen, Arnd,

On 2015/5/21 6:25, Stephen Boyd wrote:
> On 05/20/15 03:29, Bintian Wang wrote:
>> Add clock drivers for hi6220 SoC, this driver controls the SoC
>> registers to supply different clocks to different IPs in the SoC.
>>
>> We add one divider clock for hi6220 because the divider in hi6220
>> also has a mask bit but it doesnot obey the rule defined by flag
>> "CLK_DIVIDER_HIWORD_MASK", we can not get index of the mask bit by
>> left shift fixed bits (e.g. 16 bits), so we add this divider clock
>> to handle it.
>>
>> Signed-off-by: Jorge Ramirez-Ortiz <jorge.ramirez-ortiz@linaro.org>
>> Signed-off-by: Bintian Wang <bintian.wang@huawei.com>
>> Acked-by: Haojian Zhuang <haojian.zhuang@linaro.org>
>> Reviewed-by: Zhangfei Gao <zhangfei.gao@linaro.org>
>> Tested-by: Will Deacon <will.deacon@arm.com>
>> Tested-by: Tyler Baker <tyler.baker@linaro.org>
>> ---
>>   drivers/clk/Kconfig                       |    2 +
>>   drivers/clk/Makefile                      |    4 +-
>>   drivers/clk/hisilicon/Kconfig             |    6 +
>>   drivers/clk/hisilicon/Makefile            |    3 +-
>>   drivers/clk/hisilicon/clk-hi6220.c        |  291 +++++++++++++++++++++++++++++
>>   drivers/clk/hisilicon/clk.c               |   29 +++
>>   drivers/clk/hisilicon/clk.h               |   17 ++
>>   drivers/clk/hisilicon/clkdivider-hi6220.c |  156 ++++++++++++++++
>>   include/dt-bindings/clock/hi6220-clock.h  |  173 +++++++++++++++++
>>   9 files changed, 677 insertions(+), 4 deletions(-)
>>   create mode 100644 drivers/clk/hisilicon/Kconfig
>>   create mode 100644 drivers/clk/hisilicon/clk-hi6220.c
>>   create mode 100644 drivers/clk/hisilicon/clkdivider-hi6220.c
>>   create mode 100644 include/dt-bindings/clock/hi6220-clock.h
>>
>> diff --git a/drivers/clk/Kconfig b/drivers/clk/Kconfig
>> index 9897f35..18bb930 100644
>> --- a/drivers/clk/Kconfig
>> +++ b/drivers/clk/Kconfig
>> @@ -150,6 +150,8 @@ config COMMON_CLK_CDCE706
>>   	---help---
>>   	  This driver supports TI CDCE706 programmable 3-PLL clock synthesizer.
>>
>> +source "drivers/clk/hisilicon/Kconfig"
>> +
>>   source "drivers/clk/qcom/Kconfig"
>>
>
> There's going to be a merge conflict here if this doesn't go through the
> clk tree.
Hello Arnd, how about the clk driver of hi6220 goes through the clk
tree and those dts and arch patches go through arm-soc?

If there is no problem, I will split the clock header file to a
single patch for your convenience.
>
>>
>> +
>> +static void __init hi6220_clk_sys_init(struct device_node *np)
>> +{
>> +	struct hisi_clock_data *clk_data;
>> +
>> +	clk_data = hisi_clk_init(np, HI6220_SYS_NR_CLKS);
>> +	if (!clk_data)
>> +		return;
>> +
>> +	hisi_clk_register_gate_sep(hi6220_separated_gate_clks_sys,
>> +			ARRAY_SIZE(hi6220_separated_gate_clks_sys), clk_data);
>> +
>> +	hisi_clk_register_mux(hi6220_mux_clks_sys,
>> +			ARRAY_SIZE(hi6220_mux_clks_sys), clk_data);
>> +
>> +	hi6220_clk_register_divider(hi6220_div_clks_sys,
>> +			ARRAY_SIZE(hi6220_div_clks_sys), clk_data);
>> +
>> +	if (!clk_data_ao)
>> +		return;
>> +
>> +	/* enable high speed clock on UART1 mux */
>> +	clk_set_parent(clk_data->clk_data.clks[HI6220_UART1_SRC],
>> +			clk_data_ao->clk_data.clks[HI6220_150M]);
>
> Sorry I missed this one earlier. Can we do this clk_set_parent() through
> assigned-parents instead?
Uart1 has two clock parents in hi6220, and use "clk_tcxo" by default,
we use uart1 to connect BT in HiKey, and switch to "clk_150m" for high 
speed mode of BT, but pl011 has no code to set clock rate or set clock
parents operation, so it's a easy way to do that here.

I expected an #include <linux/clk.h> for the
> usage of clk_set_parent() here so I didn't look hard to see if consumer
> APIs were being used.
OK, I will add in next version 8.

Thanks,

Bintian
>
> Otherwise the patch looks fine.
>