Message-ID: <1948642d-dab9-4f20-9408-de7c952b9109@linaro.org>
Date:   Thu, 2 Feb 2023 16:56:46 +0100
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Subject: Re: [PATCH 1/6] clk: qcom: apss-ipq-pll: refactor the driver to
 accommodate different PLL types
Content-Language: en-US
To:     Kathiravan T <quic_kathirav@quicinc.com>, agross@kernel.org,
        andersson@kernel.org, mturquette@baylibre.com, sboyd@kernel.org,
        robh+dt@kernel.org, krzysztof.kozlowski+dt@linaro.org,
        jassisinghbrar@gmail.com, linux-arm-msm@vger.kernel.org,
        linux-clk@vger.kernel.org, devicetree@vger.kernel.org,
        linux-kernel@vger.kernel.org
References: <20230202145208.2328032-1-quic_kathirav@quicinc.com>
 <20230202145208.2328032-2-quic_kathirav@quicinc.com>
 <97e9ae36-6736-0db8-4044-4e874c5af5f4@linaro.org>
 <9ebaa72c-e4d5-ddb4-9d3c-f0d669465991@quicinc.com>
From:   Konrad Dybcio <konrad.dybcio@linaro.org>
In-Reply-To: <9ebaa72c-e4d5-ddb4-9d3c-f0d669465991@quicinc.com>
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Precedence: bulk


On 2.02.2023 16:37, Kathiravan T wrote:
> 
> On 2/2/2023 8:45 PM, Konrad Dybcio wrote:
>>
>> On 2.02.2023 15:52, Kathiravan T wrote:
>>> APSS PLL found on the IPQ8074 and IPQ6018 are of type Huayra PLL. But,
>>> IPQ5332 APSS PLL is of type Stromer Plus. To accommodate both these PLLs,
>>> refactor the driver to take the clk_alpha_pll, alpha_pll_config via device
>>> data.
>>>
>>> Signed-off-by: Kathiravan T <quic_kathirav@quicinc.com>
>>> ---
>>>   drivers/clk/qcom/apss-ipq-pll.c | 55 +++++++++++++++++++++------------
>>>   1 file changed, 36 insertions(+), 19 deletions(-)
>>>
>>> diff --git a/drivers/clk/qcom/apss-ipq-pll.c b/drivers/clk/qcom/apss-ipq-pll.c
>>> index a5aea27eb867..6e815e8b7fe4 100644
>>> --- a/drivers/clk/qcom/apss-ipq-pll.c
>>> +++ b/drivers/clk/qcom/apss-ipq-pll.c
>>> @@ -8,20 +8,22 @@
>>>     #include "clk-alpha-pll.h"
>>>   -static const u8 ipq_pll_offsets[] = {
>>> -    [PLL_OFF_L_VAL] = 0x08,
>>> -    [PLL_OFF_ALPHA_VAL] = 0x10,
>>> -    [PLL_OFF_USER_CTL] = 0x18,
>>> -    [PLL_OFF_CONFIG_CTL] = 0x20,
>>> -    [PLL_OFF_CONFIG_CTL_U] = 0x24,
>>> -    [PLL_OFF_STATUS] = 0x28,
>>> -    [PLL_OFF_TEST_CTL] = 0x30,
>>> -    [PLL_OFF_TEST_CTL_U] = 0x34,
>>> +static const u8 ipq_pll_offsets[][PLL_OFF_MAX_REGS] = {
>>> +    [CLK_ALPHA_PLL_TYPE_HUAYRA] =  {
>> Is it really huayra? The definition in clk-alpha-pll.c is
>> different..
> 
> 
> As per the HW document, yes it is Huayra. When you say "different", I understand these offsets are not matching with the one in clk-alpha-pll.c right? I checked with the sub system owner and they said it is expected since these PLLs are specific to each subsystem(A53 and GCC), so the offsets are different.
Okay, that makes sense. Could you please leave a comment about this
in the code?

Konrad
> 
> 
> Thanks,
> 
> Kathiravan T.
> 
> 
>>
>>
>> Konrad
>>> +        [PLL_OFF_L_VAL] = 0x08,
>>> +        [PLL_OFF_ALPHA_VAL] = 0x10,
>>> +        [PLL_OFF_USER_CTL] = 0x18,
>>> +        [PLL_OFF_CONFIG_CTL] = 0x20,
>>> +        [PLL_OFF_CONFIG_CTL_U] = 0x24,
>>> +        [PLL_OFF_STATUS] = 0x28,
>>> +        [PLL_OFF_TEST_CTL] = 0x30,
>>> +        [PLL_OFF_TEST_CTL_U] = 0x34,
>>> +    },
>>>   };
>>>   -static struct clk_alpha_pll ipq_pll = {
>>> +static struct clk_alpha_pll ipq_pll_huayra = {
>>>       .offset = 0x0,
>>> -    .regs = ipq_pll_offsets,
>>> +    .regs = ipq_pll_offsets[CLK_ALPHA_PLL_TYPE_HUAYRA],
>>>       .flags = SUPPORTS_DYNAMIC_UPDATE,
>>>       .clkr = {
>>>           .enable_reg = 0x0,
>>> @@ -61,6 +63,21 @@ static const struct alpha_pll_config ipq8074_pll_config = {
>>>       .test_ctl_hi_val = 0x4000,
>>>   };
>>>   +struct apss_pll_data {
>>> +    struct clk_alpha_pll *pll;
>>> +    const struct alpha_pll_config *pll_config;
>>> +};
>>> +
>>> +static struct apss_pll_data ipq8074_pll_data = {
>>> +    .pll = &ipq_pll_huayra,
>>> +    .pll_config = &ipq8074_pll_config,
>>> +};
>>> +
>>> +static struct apss_pll_data ipq6018_pll_data = {
>>> +    .pll = &ipq_pll_huayra,
>>> +    .pll_config = &ipq6018_pll_config,
>>> +};
>>> +
>>>   static const struct regmap_config ipq_pll_regmap_config = {
>>>       .reg_bits        = 32,
>>>       .reg_stride        = 4,
>>> @@ -71,7 +88,7 @@ static const struct regmap_config ipq_pll_regmap_config = {
>>>     static int apss_ipq_pll_probe(struct platform_device *pdev)
>>>   {
>>> -    const struct alpha_pll_config *ipq_pll_config;
>>> +    const struct apss_pll_data *data;
>>>       struct device *dev = &pdev->dev;
>>>       struct regmap *regmap;
>>>       void __iomem *base;
>>> @@ -85,23 +102,23 @@ static int apss_ipq_pll_probe(struct platform_device *pdev)
>>>       if (IS_ERR(regmap))
>>>           return PTR_ERR(regmap);
>>>   -    ipq_pll_config = of_device_get_match_data(&pdev->dev);
>>> -    if (!ipq_pll_config)
>>> +    data = of_device_get_match_data(&pdev->dev);
>>> +    if (!data)
>>>           return -ENODEV;
>>>   -    clk_alpha_pll_configure(&ipq_pll, regmap, ipq_pll_config);
>>> +    clk_alpha_pll_configure(data->pll, regmap, data->pll_config);
>>>   -    ret = devm_clk_register_regmap(dev, &ipq_pll.clkr);
>>> +    ret = devm_clk_register_regmap(dev, &data->pll->clkr);
>>>       if (ret)
>>>           return ret;
>>>         return devm_of_clk_add_hw_provider(dev, of_clk_hw_simple_get,
>>> -                       &ipq_pll.clkr.hw);
>>> +                       &data->pll->clkr.hw);
>>>   }
>>>     static const struct of_device_id apss_ipq_pll_match_table[] = {
>>> -    { .compatible = "qcom,ipq6018-a53pll", .data = &ipq6018_pll_config },
>>> -    { .compatible = "qcom,ipq8074-a53pll", .data = &ipq8074_pll_config },
>>> +    { .compatible = "qcom,ipq6018-a53pll", .data = &ipq6018_pll_data },
>>> +    { .compatible = "qcom,ipq8074-a53pll", .data = &ipq8074_pll_data },
>>>       { }
>>>   };
>>>   MODULE_DEVICE_TABLE(of, apss_ipq_pll_match_table);