[PATCH V3 1/4] cpufreq: exynos: Adding cpufreq driver for exynos5440
Sylwester Nawrocki
s.nawrocki at samsung.com
Thu Mar 7 10:28:00 EST 2013
On 03/07/2013 05:13 AM, Amit Daniel Kachhap wrote:
> +/* Register definations */
s/definations/definitions
> +#define XMU_DVFS_CTRL 0x0060
> +#define XMU_PMU_P0_7 0x0064
> +#define XMU_C0_3_PSTATE 0x0090
> +#define XMU_P_LIMIT 0x00A0
> +#define XMU_P_STATUS 0x00A4
> +#define XMU_PMUEVTEN 0x00D0
> +#define XMU_PMUIRQEN 0x00D4
> +#define XMU_PMUIRQ 0x00D8
Keeping all hex numbers lower case might be a good idea.
> +
> +/* PMU mask and shift definations */
> +#define P_VALUE_MASK 0x7
> +
> +#define XMU_DVFS_CTRL_EN_SHIFT 0
> +
> +#define P0_7_CPUCLKDEV_SHIFT 21
> +#define P0_7_CPUCLKDEV_MASK 0x7
> +#define P0_7_ATBCLKDEV_SHIFT 18
> +#define P0_7_ATBCLKDEV_MASK 0x7
> +#define P0_7_CSCLKDEV_SHIFT 15
> +#define P0_7_CSCLKDEV_MASK 0x7
> +#define P0_7_CPUEMA_SHIFT 28
> +#define P0_7_CPUEMA_MASK 0xf
> +#define P0_7_L2EMA_SHIFT 24
> +#define P0_7_L2EMA_MASK 0xf
...
> +static int exynos_cpufreq_probe(struct platform_device *pdev)
> +{
> + int ret = -EINVAL;
> + struct device_node *np;
> + struct resource res;
> +
> + np = of_find_compatible_node(NULL, NULL, "samsung,exynos5440-cpufreq");
> + if (!np)
> + return -ENODEV;
> +
> + dvfs_info = devm_kzalloc(&pdev->dev, sizeof(*dvfs_info), GFP_KERNEL);
> + if (!dvfs_info) {
> + ret = -ENOMEM;
> + goto err_put_node;
> + }
> +
> + dvfs_info->dev = &pdev->dev;
> + dvfs_info->dev->of_node = np;
> +
> + ret = of_address_to_resource(np, 0, &res);
> + if (ret)
> + goto err_put_node;
> +
> + dvfs_info->base = devm_ioremap(dvfs_info->dev, res.start,
There is a devm_ioremap_resource() function that has been introduced
recently. It could simplify this code a bit and is preferred over
devm_ioremap().
> + resource_size(&res));
> + if (!dvfs_info->base) {
> + pr_err("No cpufreq memory map found\n");
> + ret = -ENODEV;
> + goto err_put_node;
> + }
> +
> + dvfs_info->irq = irq_of_parse_and_map(np, 0);
> + if (dvfs_info->irq == 0) {
> + pr_err("No cpufreq irq found\n");
Wouldn't dev_err() be more appropriate here ?
> + ret = -ENODEV;
> + goto err_put_node;
> + }
> +
> + ret = of_init_opp_table(dvfs_info->dev);
> + if (ret) {
> + pr_err("failed to init OPP table: %d\n", ret);
> + goto err_put_node;
> + }
> +
> + ret = opp_init_cpufreq_table(dvfs_info->dev, &dvfs_info->freq_table);
> + if (ret) {
> + pr_err("failed to init cpufreq table: %d\n", ret);
> + goto err_put_node;
> + }
> + dvfs_info->freq_count = opp_get_opp_count(dvfs_info->dev);
> + exynos_sort_descend_freq_table();
> +
> + if (of_property_read_u32(np, "clock-latency", &dvfs_info->latency))
> + dvfs_info->latency = DEF_TRANS_LATENCY;
> +
> + dvfs_info->cpu_clk = devm_clk_get(dvfs_info->dev, "armclk");
> + if (IS_ERR_OR_NULL(dvfs_info->cpu_clk)) {
devm_clk_get() return value needs to be checked with IS_ERR(),
not IS_ERR_OR_NULL().
> + pr_err("Failed to get cpu clock\n");
> + ret = PTR_ERR(dvfs_info->cpu_clk);
> + goto err_free_table;
> + }
> +
> + dvfs_info->cur_frequency = clk_get_rate(dvfs_info->cpu_clk);
> + if (!dvfs_info->cur_frequency) {
> + pr_err("Failed to get clock rate\n");
> + ret = -EINVAL;
> + goto err_free_table;
> + }
> + dvfs_info->cur_frequency /= 1000;
> +
> + INIT_WORK(&dvfs_info->irq_work, exynos_cpufreq_work);
> + if (devm_request_irq(dvfs_info->dev, dvfs_info->irq, exynos_cpufreq_irq,
> + IRQF_TRIGGER_NONE, CPUFREQ_NAME, dvfs_info)) {
> + pr_err("Failed to register IRQ\n");
> + ret = -ENODEV;
> + goto err_free_table;
> + }
> +
> + ret = init_div_table();
> + if (ret) {
> + pr_err("Failed to initialise div table\n");
> + goto err_free_table;
> + }
> +
> + exynos_enable_dvfs();
> + ret = cpufreq_register_driver(&exynos_driver);
> + if (ret) {
> + pr_err("%s: failed to register cpufreq driver\n", __func__);
> + goto err_free_table;
> + }
> +
> + of_node_put(np);
> + dvfs_info->dvfs_enable = true;
> + pr_info("exynos5440 DVFS initialized.\n");
dev_info() ?
> + return 0;
> +
> +err_free_table:
> + opp_free_cpufreq_table(dvfs_info->dev, &dvfs_info->freq_table);
> +err_put_node:
> + of_node_put(np);
> + pr_err("%s: failed initialization\n", __func__);
Is this really needed ? This failure will be logged by the driver core
anyway.
> + return ret;
> +
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