Re: [PATCH 4/7] cpufreq: qcom-hw: Make use of of_match data for offsets and row size

[Bjorn Andersson <bjorn.andersson@linaro.org>]

On Tue 08 Sep 02:57 CDT 2020, Manivannan Sadhasivam wrote:

> For preparing the driver to handle further SoC revisions, let's use the
> of_match data for getting the device specific offsets and row size instead
> of defining them globally.
> 
> Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
> ---
>  drivers/cpufreq/qcom-cpufreq-hw.c | 96 +++++++++++++++++++++----------
>  1 file changed, 66 insertions(+), 30 deletions(-)
> 
> diff --git a/drivers/cpufreq/qcom-cpufreq-hw.c b/drivers/cpufreq/qcom-cpufreq-hw.c
> index ccea34f61152..41853db7c9b8 100644
> --- a/drivers/cpufreq/qcom-cpufreq-hw.c
> +++ b/drivers/cpufreq/qcom-cpufreq-hw.c
> @@ -19,15 +19,21 @@
>  #define LUT_L_VAL			GENMASK(7, 0)
>  #define LUT_CORE_COUNT			GENMASK(18, 16)
>  #define LUT_VOLT			GENMASK(11, 0)
> -#define LUT_ROW_SIZE			32
>  #define CLK_HW_DIV			2
>  #define LUT_TURBO_IND			1
>  
> -/* Register offsets */
> -#define REG_ENABLE			0x0
> -#define REG_FREQ_LUT			0x110
> -#define REG_VOLT_LUT			0x114
> -#define REG_PERF_STATE			0x920
> +struct qcom_cpufreq_soc_data {
> +	u32 reg_enable;
> +	u32 reg_freq_lut;
> +	u32 reg_volt_lut;
> +	u32 reg_perf_state;
> +	u8 lut_row_size;
> +};
> +
> +struct qcom_cpufreq_data {
> +	void __iomem *base;
> +	const struct qcom_cpufreq_soc_data *soc_data;
> +};
>  
>  static unsigned long cpu_hw_rate, xo_rate;
>  static bool icc_scaling_enabled;
> @@ -76,10 +82,11 @@ static int qcom_cpufreq_update_opp(struct device *cpu_dev,
>  static int qcom_cpufreq_hw_target_index(struct cpufreq_policy *policy,
>  					unsigned int index)
>  {
> -	void __iomem *perf_state_reg = policy->driver_data;
> +	struct qcom_cpufreq_data *data = policy->driver_data;
> +	const struct qcom_cpufreq_soc_data *soc_data = data->soc_data;
>  	unsigned long freq = policy->freq_table[index].frequency;
>  
> -	writel_relaxed(index, perf_state_reg);
> +	writel_relaxed(index, data->base + soc_data->reg_perf_state);
>  
>  	if (icc_scaling_enabled)
>  		qcom_cpufreq_set_bw(policy, freq);
> @@ -91,7 +98,8 @@ static int qcom_cpufreq_hw_target_index(struct cpufreq_policy *policy,
>  
>  static unsigned int qcom_cpufreq_hw_get(unsigned int cpu)
>  {
> -	void __iomem *perf_state_reg;
> +	struct qcom_cpufreq_data *data;
> +	const struct qcom_cpufreq_soc_data *soc_data;
>  	struct cpufreq_policy *policy;
>  	unsigned int index;
>  
> @@ -99,9 +107,10 @@ static unsigned int qcom_cpufreq_hw_get(unsigned int cpu)
>  	if (!policy)
>  		return 0;
>  
> -	perf_state_reg = policy->driver_data;
> +	data = policy->driver_data;
> +	soc_data = data->soc_data;
>  
> -	index = readl_relaxed(perf_state_reg);
> +	index = readl_relaxed(data->base + soc_data->reg_perf_state);
>  	index = min(index, LUT_MAX_ENTRIES - 1);
>  
>  	return policy->freq_table[index].frequency;
> @@ -110,12 +119,13 @@ static unsigned int qcom_cpufreq_hw_get(unsigned int cpu)
>  static unsigned int qcom_cpufreq_hw_fast_switch(struct cpufreq_policy *policy,
>  						unsigned int target_freq)
>  {
> -	void __iomem *perf_state_reg = policy->driver_data;
> +	struct qcom_cpufreq_data *data = policy->driver_data;
> +	const struct qcom_cpufreq_soc_data *soc_data = data->soc_data;
>  	unsigned int index;
>  	unsigned long freq;
>  
>  	index = policy->cached_resolved_idx;
> -	writel_relaxed(index, perf_state_reg);
> +	writel_relaxed(index, data->base + soc_data->reg_perf_state);
>  
>  	freq = policy->freq_table[index].frequency;
>  	arch_set_freq_scale(policy->related_cpus, freq,
> @@ -125,8 +135,7 @@ static unsigned int qcom_cpufreq_hw_fast_switch(struct cpufreq_policy *policy,
>  }
>  
>  static int qcom_cpufreq_hw_read_lut(struct device *cpu_dev,
> -				    struct cpufreq_policy *policy,
> -				    void __iomem *base)
> +				    struct cpufreq_policy *policy)
>  {
>  	u32 data, src, lval, i, core_count, prev_freq = 0, freq;
>  	u32 volt;
> @@ -134,6 +143,8 @@ static int qcom_cpufreq_hw_read_lut(struct device *cpu_dev,
>  	struct dev_pm_opp *opp;
>  	unsigned long rate;
>  	int ret;
> +	struct qcom_cpufreq_data *drv_data = policy->driver_data;
> +	const struct qcom_cpufreq_soc_data *soc_data = drv_data->soc_data;
>  
>  	table = kcalloc(LUT_MAX_ENTRIES + 1, sizeof(*table), GFP_KERNEL);
>  	if (!table)
> @@ -160,14 +171,14 @@ static int qcom_cpufreq_hw_read_lut(struct device *cpu_dev,
>  	}
>  
>  	for (i = 0; i < LUT_MAX_ENTRIES; i++) {
> -		data = readl_relaxed(base + REG_FREQ_LUT +
> -				      i * LUT_ROW_SIZE);
> +		data = readl_relaxed(drv_data->base + soc_data->reg_freq_lut +
> +				      i * soc_data->lut_row_size);
>  		src = FIELD_GET(LUT_SRC, data);
>  		lval = FIELD_GET(LUT_L_VAL, data);
>  		core_count = FIELD_GET(LUT_CORE_COUNT, data);
>  
> -		data = readl_relaxed(base + REG_VOLT_LUT +
> -				      i * LUT_ROW_SIZE);
> +		data = readl_relaxed(drv_data->base + soc_data->reg_volt_lut +
> +				      i * soc_data->lut_row_size);
>  		volt = FIELD_GET(LUT_VOLT, data) * 1000;
>  
>  		if (src)
> @@ -237,6 +248,20 @@ static void qcom_get_related_cpus(int index, struct cpumask *m)
>  	}
>  }
>  
> +static const struct qcom_cpufreq_soc_data qcom_soc_data = {
> +	.reg_enable = 0x0,
> +	.reg_freq_lut = 0x110,
> +	.reg_volt_lut = 0x114,
> +	.reg_perf_state = 0x920,
> +	.lut_row_size = 32,
> +};
> +
> +static const struct of_device_id qcom_cpufreq_hw_match[] = {
> +	{ .compatible = "qcom,cpufreq-hw", .data = &qcom_soc_data },
> +	{}
> +};
> +MODULE_DEVICE_TABLE(of, qcom_cpufreq_hw_match);
> +
>  static int qcom_cpufreq_hw_cpu_init(struct cpufreq_policy *policy)
>  {
>  	struct platform_device *pdev = cpufreq_get_driver_data();
> @@ -246,6 +271,8 @@ static int qcom_cpufreq_hw_cpu_init(struct cpufreq_policy *policy)
>  	struct device *cpu_dev;
>  	struct resource *res;
>  	void __iomem *base;
> +	struct qcom_cpufreq_data *data;
> +	const struct of_device_id *match;
>  	int ret, index;
>  
>  	cpu_dev = get_cpu_device(policy->cpu);
> @@ -275,8 +302,23 @@ static int qcom_cpufreq_hw_cpu_init(struct cpufreq_policy *policy)
>  	if (!base)
>  		return -ENOMEM;
>  
> +	data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
> +	if (!data) {
> +		ret = -ENOMEM;
> +		goto error;
> +	}
> +
> +	match = of_match_device(qcom_cpufreq_hw_match, &pdev->dev);

Rather than having to move the qcom_cpufreq_hw_match table and reference
it here, use the more succinct:

	data->soc-data = of_device_get_match_data(&pdev->dev);

Apart from this, I think the patch looks good.

> +	if (!match) {
> +		ret = -ENODEV;
> +		goto error;
> +	}
> +
> +	data->soc_data = match->data;
> +	data->base = base;
> +
>  	/* HW should be in enabled state to proceed */
> -	if (!(readl_relaxed(base + REG_ENABLE) & 0x1)) {
> +	if (!(readl_relaxed(base + data->soc_data->reg_enable) & 0x1)) {
>  		dev_err(dev, "Domain-%d cpufreq hardware not enabled\n", index);
>  		ret = -ENODEV;
>  		goto error;
> @@ -289,9 +331,9 @@ static int qcom_cpufreq_hw_cpu_init(struct cpufreq_policy *policy)
>  		goto error;
>  	}
>  
> -	policy->driver_data = base + REG_PERF_STATE;
> +	policy->driver_data = data;
>  
> -	ret = qcom_cpufreq_hw_read_lut(cpu_dev, policy, base);
> +	ret = qcom_cpufreq_hw_read_lut(cpu_dev, policy);
>  	if (ret) {
>  		dev_err(dev, "Domain-%d failed to read LUT\n", index);
>  		goto error;
> @@ -315,13 +357,13 @@ static int qcom_cpufreq_hw_cpu_init(struct cpufreq_policy *policy)
>  static int qcom_cpufreq_hw_cpu_exit(struct cpufreq_policy *policy)
>  {
>  	struct device *cpu_dev = get_cpu_device(policy->cpu);
> -	void __iomem *base = policy->driver_data - REG_PERF_STATE;
> +	struct qcom_cpufreq_data *data = policy->driver_data;
>  	struct platform_device *pdev = cpufreq_get_driver_data();
>  
>  	dev_pm_opp_remove_all_dynamic(cpu_dev);
>  	dev_pm_opp_of_cpumask_remove_table(policy->related_cpus);
>  	kfree(policy->freq_table);
> -	devm_iounmap(&pdev->dev, base);
> +	devm_iounmap(&pdev->dev, data->base);

PS. Unrelated to your series, I don't like the fact that we use devres
in code paths that's only indirectly tied to the device's life cycle.

Regards,
Bjorn

>  
>  	return 0;
>  }
> @@ -391,12 +433,6 @@ static int qcom_cpufreq_hw_driver_remove(struct platform_device *pdev)
>  	return cpufreq_unregister_driver(&cpufreq_qcom_hw_driver);
>  }
>  
> -static const struct of_device_id qcom_cpufreq_hw_match[] = {
> -	{ .compatible = "qcom,cpufreq-hw" },
> -	{}
> -};
> -MODULE_DEVICE_TABLE(of, qcom_cpufreq_hw_match);
> -
>  static struct platform_driver qcom_cpufreq_hw_driver = {
>  	.probe = qcom_cpufreq_hw_driver_probe,
>  	.remove = qcom_cpufreq_hw_driver_remove,
> -- 
> 2.17.1
>