On 30-07-21, 00:08, Hector Yuan wrote:

From: "Hector.Yuan" <redacted>

Add cpufreq HW support

Please write a proper commit log, what you are adding and which SoCs
it will apply to. Also add a full stop (.) at the end.

Signed-off-by: Hector.Yuan <redacted>
---
 drivers/cpufreq/Kconfig.arm           |   12 ++
 drivers/cpufreq/Makefile              |    1 +
 drivers/cpufreq/mediatek-cpufreq-hw.c |  357 +++++++++++++++++++++++++++++++++
 include/linux/cpufreq.h               |   39 ++++

The changes to cpufreq.h should be done in a separate patch.

Won't this fit in a single line ?

+
+		prev_freq = freq;
+	}
+
+	c->table[i].frequency = CPUFREQ_TABLE_END;
+	c->nr_opp = i;
+
+	return 0;
+}
+
+static int mtk_cpu_resources_init(struct platform_device *pdev,
+				  unsigned int cpu, int index,
+				  const u16 *offsets)
+{
+	struct cpufreq_mtk *c;
+	struct device *dev = &pdev->dev;
+	int ret, i;
+	void __iomem *base;
+
+	if (mtk_freq_domain_map[cpu])

This should not happen anymore, isn't it ?

+		return 0;
+
+	c = devm_kzalloc(dev, sizeof(*c), GFP_KERNEL);
+	if (!c)
+		return -ENOMEM;
+
+	base = devm_platform_ioremap_resource(pdev, index);
+	if (IS_ERR(base))
+		return PTR_ERR(base);
+
+	for (i = REG_FREQ_LUT_TABLE; i < REG_ARRAY_SIZE; i++)
+		c->reg_bases[i] = base + offsets[i];
+
+	ret = of_perf_domain_get_sharing_cpumask(index, "performance-domains",

Instead of parsing parsing "performance-domains" twice, I would rather
pass a CPU number here instead of index.

+						 "#performance-domain-cells",
+						 &c->related_cpus);

You could have directly passed policy->cpus here instead.

+	if (ret) {
+		dev_info(dev, "Domain-%d failed to get related CPUs\n", index);
+		return ret;
+	}
+
+	ret = mtk_cpu_create_freq_table(pdev, c);
+	if (ret) {
+		dev_info(dev, "Domain-%d failed to create freq table\n", index);
+		return ret;
+	}
+
+	mtk_freq_domain_map[cpu] = c;

I will rather use policy->driver_data to store this now.

+
+	return 0;
+}
+
+static int mtk_cpufreq_hw_cpu_init(struct cpufreq_policy *policy)
+{
+	struct platform_device *pdev = cpufreq_get_driver_data();
+	struct cpufreq_mtk *c;
+	struct device *cpu_dev;
+	struct em_data_callback em_cb = EM_DATA_CB(mtk_cpufreq_get_cpu_power);
+	struct pm_qos_request *qos_request;
+	struct device_node *cpu_np;
+	struct of_phandle_args args;
+	const u16 *offsets;
+	unsigned int latency;
+	int sig, pwr_hw = CPUFREQ_HW_STATUS | SVS_HW_STATUS;
+	int ret;

It looks much more organized when the variable definitions are in
decreasing order of their length, instead of the random order as it is
right now.

+
+	offsets = of_device_get_match_data(&pdev->dev);
+	if (!offsets)
+		return -EINVAL;
+
+	cpu_np = of_cpu_device_node_get(policy->cpu);
+	if (!cpu_np) {
+		dev_info(&pdev->dev, "Failed to get cpu %d device\n",
+			 policy->cpu);
+		return -ENODEV;
+	}
+
+	ret = of_parse_phandle_with_args(cpu_np, "performance-domains",
+					 "#performance-domain-cells", 0,
+					 &args);
+	if (ret < 0)

What about dropping cpu_np and same later in the code as well ?

+		return ret;
+
+	/* Get the bases of cpufreq for domains */
+	ret = mtk_cpu_resources_init(pdev, policy->cpu, args.args[0], offsets);
+	if (ret) {
+		dev_info(&pdev->dev, "CPUFreq resource init failed\n");
+		return ret;
+	}
+
+	cpu_dev = get_cpu_device(policy->cpu);
+	if (!cpu_dev) {
+		pr_err("failed to get cpu%d device\n", policy->cpu);
+		return -ENODEV;
+	}
+
+	c = mtk_freq_domain_map[policy->cpu];
+	if (!c) {
+		pr_err("No scaling support for CPU%d\n", policy->cpu);
+		return -ENODEV;
+	}
+
+	cpumask_copy(policy->cpus, &c->related_cpus);
+
+	policy->freq_table = c->table;
+	policy->driver_data = c;

Oh you already do this, you can remove mtk_freq_domain_map array now.

+
+	latency = readl_relaxed(c->reg_bases[REG_FREQ_LATENCY]);
+	if (!latency)
+		latency = CPUFREQ_ETERNAL;
+
+	/* us convert to ns */
+	policy->cpuinfo.transition_latency = latency * 1000;

You want to multiple CPUFREQ_ETERNAL too ?

+
+	policy->fast_switch_possible = true;
+
+	qos_request = kzalloc(sizeof(*qos_request), GFP_KERNEL);

This is a small structure, why not allocate it on stack instead ?

+	if (!qos_request)
+		return -ENOMEM;
+
+	/* Let CPUs leave idle-off state for SVS CPU initializing */
+	cpu_latency_qos_add_request(qos_request, 0);
+
+	/* HW should be in enabled state to proceed now */
+	writel_relaxed(0x1, c->reg_bases[REG_FREQ_ENABLE]);
+
+	if (readl_poll_timeout(c->reg_bases[REG_FREQ_HW_STATE], sig,
+			       (sig & pwr_hw) == pwr_hw, POLL_USEC,
+			       TIMEOUT_USEC)) {
+		if (!(sig & CPUFREQ_HW_STATUS)) {
+			pr_info("cpufreq hardware of CPU%d is not enabled\n",
+				policy->cpu);
+			return -ENODEV;
+		}
+
+		pr_info("SVS of CPU%d is not enabled\n", policy->cpu);
+	}
+
+	cpu_latency_qos_remove_request(qos_request);
+
+	em_dev_register_perf_domain(cpu_dev, c->nr_opp, &em_cb, policy->cpus, true);
+
+	kfree(qos_request);

Why free after registering for em ? And also move the entire qos thing
into a separate routine instead of adding it to ->init().

+
+	return 0;
+}
+
+static int mtk_cpufreq_hw_cpu_exit(struct cpufreq_policy *policy)
+{
+	struct cpufreq_mtk *c;
+
+	c = mtk_freq_domain_map[policy->cpu];
+
+	/* HW should be in paused state now */
+	writel_relaxed(0x0, c->reg_bases[REG_FREQ_ENABLE]);

Please make sure each and every resource is freed here and in probe on
failures.

+
+	return 0;
+}
+
+static struct cpufreq_driver cpufreq_mtk_hw_driver = {
+	.flags		= CPUFREQ_NEED_INITIAL_FREQ_CHECK |
+			  CPUFREQ_HAVE_GOVERNOR_PER_POLICY |
+			  CPUFREQ_IS_COOLING_DEV,
+	.verify		= cpufreq_generic_frequency_table_verify,
+	.target_index	= mtk_cpufreq_hw_target_index,
+	.get		= mtk_cpufreq_hw_get,
+	.init		= mtk_cpufreq_hw_cpu_init,
+	.exit		= mtk_cpufreq_hw_cpu_exit,
+	.fast_switch	= mtk_cpufreq_hw_fast_switch,
+	.name		= "mtk-cpufreq-hw",
+	.attr		= cpufreq_generic_attr,
+};
+
+static int mtk_cpufreq_hw_driver_probe(struct platform_device *pdev)
+{
+	int ret;
+
+	cpufreq_mtk_hw_driver.driver_data = pdev;
+
+	ret = cpufreq_register_driver(&cpufreq_mtk_hw_driver);
+	if (ret) {
+		dev_err(&pdev->dev, "CPUFreq HW driver failed to register\n");
+		return ret;
+	}
+
+	return 0;

You can do return ret here and drop the earlier return and its {}.

+}
+
+static int mtk_cpufreq_hw_driver_remove(struct platform_device *pdev)
+{
+	return cpufreq_unregister_driver(&cpufreq_mtk_hw_driver);
+}
+
+static const struct of_device_id mtk_cpufreq_hw_match[] = {
+	{ .compatible = "mediatek,cpufreq-hw", .data = &cpufreq_mtk_offsets },
+	{}
+};
+
+static struct platform_driver mtk_cpufreq_hw_driver = {
+	.probe = mtk_cpufreq_hw_driver_probe,
+	.remove = mtk_cpufreq_hw_driver_remove,
+	.driver = {
+		.name = "mtk-cpufreq-hw",
+		.of_match_table = mtk_cpufreq_hw_match,
+	},
+};
+module_platform_driver(mtk_cpufreq_hw_driver);
+
+MODULE_DESCRIPTION("Mediatek cpufreq-hw driver");
+MODULE_LICENSE("GPL v2");

You can add Module-author as well here if you want.

There is another CONFIG_CPU_FREQ a few lines above, please use the
same block for this routine as well.

+static inline int of_perf_domain_get_sharing_cpumask(int index, const char *list_name,
+						     const char *cell_name,
+						     struct cpumask *cpumask)
+{
+	struct device_node *cpu_np;
+	struct of_phandle_args args;
+	int cpu, ret;
+
+	for_each_possible_cpu(cpu) {
+		cpu_np = of_cpu_device_node_get(cpu);
+		if (!cpu_np)
+			continue;
+
+		ret = of_parse_phandle_with_args(cpu_np, list_name,
+						 cell_name, 0,
+						 &args);
+
+		of_node_put(cpu_np);
+		if (ret < 0)
+			continue;
+
+		if (index == args.args[0])
+			cpumask_set_cpu(cpu, cpumask);
+	}
+
+	return 0;
+}
+#else
+static inline int of_perf_domain_get_sharing_cpumask(int index, const char *list_name,
+						     const char *cell_name,
+						     struct cpumask *cpumask)
+{
+	return 0;

	return -EOPNOTSUPP;

+}
+#endif

-- 
viresh