[PATCH] cpufreq: qoriq: Make the driver usable on all QorIQ platforms
Viresh Kumar
viresh.kumar at linaro.org
Fri Oct 17 19:08:54 AEDT 2014
On 17 October 2014 08:43, <B29983 at freescale.com> wrote:
Hi B29983 :)
> From: Tang Yuantian <Yuantian.Tang at freescale.com>
>
> Freescale introduced new ARM core-based SoCs which support dynamic
> frequency switch feature. DFS on new SoCs are compatible with current
> PowerPC CoreNet platforms. In order to support those new platforms,
> this driver needs to be slightly adjusted. The main changes include:
>
> 1. Changed the names of driver and functions in driver.
> 2. Added two new functions get_cpu_physical_id() and get_bus_freq().
> 3. Used a new way to get all the CPUs which sharing clock wire.
>
> Signed-off-by: Tang Yuantian <Yuantian.Tang at freescale.com>
> ---
> drivers/cpufreq/Kconfig.arm | 8 ++
> drivers/cpufreq/Kconfig.powerpc | 11 +-
> drivers/cpufreq/Makefile | 2 +-
> .../{ppc-corenet-cpufreq.c => qoriq-cpufreq.c} | 150 ++++++++++++++-------
> 4 files changed, 114 insertions(+), 57 deletions(-)
> rename drivers/cpufreq/{ppc-corenet-cpufreq.c => qoriq-cpufreq.c} (72%)
>
> diff --git a/drivers/cpufreq/Kconfig.arm b/drivers/cpufreq/Kconfig.arm
> index 83a75dc..1925ae94 100644
> --- a/drivers/cpufreq/Kconfig.arm
> +++ b/drivers/cpufreq/Kconfig.arm
> @@ -247,3 +247,11 @@ config ARM_TEGRA_CPUFREQ
> default y
> help
> This adds the CPUFreq driver support for TEGRA SOCs.
> +
> +config QORIQ_CPUFREQ
> + tristate "CPU frequency scaling driver for Freescale QorIQ SoCs"
> + depends on OF && COMMON_CLK
> + select CLK_PPC_CORENET
> + help
> + This adds the CPUFreq driver support for Freescale QorIQ SoCs
> + which are capable of changing the CPU's frequency dynamically.
> diff --git a/drivers/cpufreq/Kconfig.powerpc b/drivers/cpufreq/Kconfig.powerpc
> index 72564b7..3a34248 100644
> --- a/drivers/cpufreq/Kconfig.powerpc
> +++ b/drivers/cpufreq/Kconfig.powerpc
> @@ -23,14 +23,13 @@ config CPU_FREQ_MAPLE
> This adds support for frequency switching on Maple 970FX
> Evaluation Board and compatible boards (IBM JS2x blades).
>
> -config PPC_CORENET_CPUFREQ
> - tristate "CPU frequency scaling driver for Freescale E500MC SoCs"
> - depends on PPC_E500MC && OF && COMMON_CLK
> +config QORIQ_CPUFREQ
> + tristate "CPU frequency scaling driver for Freescale QorIQ SoCs"
> + depends on OF && COMMON_CLK
> select CLK_PPC_CORENET
> help
> - This adds the CPUFreq driver support for Freescale e500mc,
> - e5500 and e6500 series SoCs which are capable of changing
> - the CPU's frequency dynamically.
> + This adds the CPUFreq driver support for Freescale QorIQ SoCs
> + which are capable of changing the CPU's frequency dynamically.
>
> config CPU_FREQ_PMAC
> bool "Support for Apple PowerBooks"
Don't need this duplication at all. Just move this to Kconfig instead
of .arm and ppc.
> diff --git a/drivers/cpufreq/ppc-corenet-cpufreq.c b/drivers/cpufreq/qoriq-cpufreq.c
> /**
> * struct cpu_data - per CPU data struct
> @@ -69,9 +68,6 @@ static const u32 *fmask;
>
> static DEFINE_PER_CPU(struct cpu_data *, cpu_data);
>
> -/* cpumask in a cluster */
> -static DEFINE_PER_CPU(cpumask_var_t, cpu_mask);
> -
> #ifndef CONFIG_SMP
> static inline const struct cpumask *cpu_core_mask(int cpu)
> {
> @@ -79,6 +75,79 @@ static inline const struct cpumask *cpu_core_mask(int cpu)
> }
> #endif
>
> +#if defined(CONFIG_PPC_E500MC)
> +static int get_cpu_physical_id(int cpu)
> +{
> + return get_hard_smp_processor_id(cpu);
> +}
> +#elif defined(CONFIG_ARM)
Wouldn't a #else work here as there are just two platforms we are
talking about ?
> +static int get_cpu_physical_id(int cpu)
> +{
> + return topology_core_id(cpu);
> +}
> +#endif
> +
> +static u32 get_bus_freq(void)
> +{
> + struct device_node *soc;
> + u32 sysfreq;
> +
> + soc = of_find_node_by_type(NULL, "soc");
> + if (!soc)
> + return 0;
> +
> + if (of_property_read_u32(soc, "bus-frequency", &sysfreq))
> + sysfreq = 0;
> +
> + of_node_put(soc);
> +
> + return sysfreq;
> +}
> +
> +static struct device_node *cpu_to_clk_node(int cpu)
> +{
> + struct device_node *np, *clk_np;
> +
> + if (!cpu_present(cpu))
> + return NULL;
> +
> + np = of_get_cpu_node(cpu, NULL);
> + if (!np)
> + return NULL;
> +
> + clk_np = of_parse_phandle(np, "clocks", 0);
> + if (!clk_np)
> + return NULL;
> +
> + of_node_put(np);
> +
> + return clk_np;
> +}
> +
> +/* traverse cpu nodes to get cpu mask of sharing clock wire */
> +static void set_affected_cpus(struct cpufreq_policy *policy)
> +{
> + struct device_node *np, *clk_np;
> + struct cpumask *dstp = policy->cpus;
> + int i;
> +
> + np = cpu_to_clk_node(policy->cpu);
> + if (!np)
> + return;
> +
> + for_each_present_cpu(i) {
> + clk_np = cpu_to_clk_node(i);
> + if (!clk_np)
> + continue;
> +
> + if (clk_np == np)
> + cpumask_set_cpu(i, dstp);
So you are depending on matching the clock-nodes from DT for
getting this information, right ? There is nothing that the architecture
gives?
> +
> + of_node_put(clk_np);
> + }
> + of_node_put(np);
> +}
> +
> /* reduce the duplicated frequencies in frequency table */
> static void freq_table_redup(struct cpufreq_frequency_table *freq_table,
> int count)
> @@ -105,6 +174,7 @@ static void freq_table_sort(struct cpufreq_frequency_table *freq_table,
> int i, j, ind;
> unsigned int freq, max_freq;
> struct cpufreq_frequency_table table;
> +
> for (i = 0; i < count - 1; i++) {
> max_freq = freq_table[i].frequency;
> ind = i;
> @@ -129,7 +199,7 @@ static void freq_table_sort(struct cpufreq_frequency_table *freq_table,
> }
> }
>
> -static int corenet_cpufreq_cpu_init(struct cpufreq_policy *policy)
> +static int qoriq_cpufreq_cpu_init(struct cpufreq_policy *policy)
> {
> struct device_node *np;
> int i, count, ret;
> @@ -145,10 +215,8 @@ static int corenet_cpufreq_cpu_init(struct cpufreq_policy *policy)
> return -ENODEV;
>
> data = kzalloc(sizeof(*data), GFP_KERNEL);
> - if (!data) {
> - pr_err("%s: no memory\n", __func__);
Wasn't this useful ?
> + if (!data)
> goto err_np;
> - }
>
> policy->clk = of_clk_get(np, 0);
> if (IS_ERR(policy->clk)) {
> @@ -170,7 +238,7 @@ static int corenet_cpufreq_cpu_init(struct cpufreq_policy *policy)
> }
>
> if (fmask)
> - mask = fmask[get_hard_smp_processor_id(cpu)];
> + mask = fmask[get_cpu_physical_id(cpu)];
> else
> mask = 0x0;
>
> @@ -201,13 +269,13 @@ static int corenet_cpufreq_cpu_init(struct cpufreq_policy *policy)
> data->table = table;
>
> /* update ->cpus if we have cluster, no harm if not */
> - cpumask_copy(policy->cpus, per_cpu(cpu_mask, cpu));
> - for_each_cpu(i, per_cpu(cpu_mask, cpu))
> + set_affected_cpus(policy);
> + for_each_cpu(i, policy->cpus)
> per_cpu(cpu_data, i) = data;
Get rid of this per-cpu data and use policy->driver_data instead.
>
> /* Minimum transition latency is 12 platform clocks */
> u64temp = 12ULL * NSEC_PER_SEC;
> - do_div(u64temp, fsl_get_sys_freq());
> + do_div(u64temp, get_bus_freq());
> policy->cpuinfo.transition_latency = u64temp + 1;
>
> of_node_put(np);
> @@ -227,7 +295,7 @@ err_np:
> return -ENODEV;
> }
>
> -static int __exit corenet_cpufreq_cpu_exit(struct cpufreq_policy *policy)
> +static int __exit qoriq_cpufreq_cpu_exit(struct cpufreq_policy *policy)
> {
> struct cpu_data *data = per_cpu(cpu_data, policy->cpu);
> unsigned int cpu;
> @@ -236,13 +304,13 @@ static int __exit corenet_cpufreq_cpu_exit(struct cpufreq_policy *policy)
> kfree(data->table);
> kfree(data);
>
> - for_each_cpu(cpu, per_cpu(cpu_mask, policy->cpu))
> + for_each_cpu(cpu, policy->cpus)
> per_cpu(cpu_data, cpu) = NULL;
>
> return 0;
> }
>
> -static int corenet_cpufreq_target(struct cpufreq_policy *policy,
> +static int qoriq_cpufreq_target(struct cpufreq_policy *policy,
> unsigned int index)
> {
> struct clk *parent;
> @@ -252,18 +320,18 @@ static int corenet_cpufreq_target(struct cpufreq_policy *policy,
> return clk_set_parent(policy->clk, parent);
> }
>
> -static struct cpufreq_driver ppc_corenet_cpufreq_driver = {
> - .name = "ppc_cpufreq",
> +static struct cpufreq_driver qoriq_cpufreq_driver = {
> + .name = "qoriq_cpufreq",
> .flags = CPUFREQ_CONST_LOOPS,
> - .init = corenet_cpufreq_cpu_init,
> - .exit = __exit_p(corenet_cpufreq_cpu_exit),
> + .init = qoriq_cpufreq_cpu_init,
> + .exit = __exit_p(qoriq_cpufreq_cpu_exit),
> .verify = cpufreq_generic_frequency_table_verify,
> - .target_index = corenet_cpufreq_target,
> + .target_index = qoriq_cpufreq_target,
> .get = cpufreq_generic_get,
> .attr = cpufreq_generic_attr,
> };
>
> -static const struct of_device_id node_matches[] __initdata = {
> +static const struct of_device_id node_matches[] __initconst = {
> { .compatible = "fsl,p2041-clockgen", .data = &sdata[0], },
> { .compatible = "fsl,p3041-clockgen", .data = &sdata[0], },
> { .compatible = "fsl,p5020-clockgen", .data = &sdata[1], },
> @@ -273,61 +341,43 @@ static const struct of_device_id node_matches[] __initdata = {
> {}
> };
>
> -static int __init ppc_corenet_cpufreq_init(void)
> +static int __init qoriq_cpufreq_init(void)
> {
> int ret;
> struct device_node *np;
> const struct of_device_id *match;
> const struct soc_data *data;
> - unsigned int cpu;
>
> np = of_find_matching_node(NULL, node_matches);
> if (!np)
> return -ENODEV;
>
> - for_each_possible_cpu(cpu) {
> - if (!alloc_cpumask_var(&per_cpu(cpu_mask, cpu), GFP_KERNEL))
> - goto err_mask;
> - cpumask_copy(per_cpu(cpu_mask, cpu), cpu_core_mask(cpu));
> - }
> -
> match = of_match_node(node_matches, np);
> data = match->data;
> if (data) {
> if (data->flag)
> fmask = data->freq_mask;
> - min_cpufreq = fsl_get_sys_freq();
> + min_cpufreq = get_bus_freq();
> } else {
> - min_cpufreq = fsl_get_sys_freq() / 2;
> + min_cpufreq = get_bus_freq() / 2;
> }
>
> of_node_put(np);
>
> - ret = cpufreq_register_driver(&ppc_corenet_cpufreq_driver);
> + ret = cpufreq_register_driver(&qoriq_cpufreq_driver);
> if (!ret)
> - pr_info("Freescale PowerPC corenet CPU frequency scaling driver\n");
> + pr_info("Freescale QorIQ CPU frequency scaling driver\n");
>
> return ret;
> -
> -err_mask:
> - for_each_possible_cpu(cpu)
> - free_cpumask_var(per_cpu(cpu_mask, cpu));
> -
> - return -ENOMEM;
> }
> -module_init(ppc_corenet_cpufreq_init);
> +module_init(qoriq_cpufreq_init);
>
> -static void __exit ppc_corenet_cpufreq_exit(void)
> +static void __exit qoriq_cpufreq_exit(void)
> {
> - unsigned int cpu;
> -
> - for_each_possible_cpu(cpu)
> - free_cpumask_var(per_cpu(cpu_mask, cpu));
> -
> - cpufreq_unregister_driver(&ppc_corenet_cpufreq_driver);
> + cpufreq_unregister_driver(&qoriq_cpufreq_driver);
> }
> -module_exit(ppc_corenet_cpufreq_exit);
> +module_exit(qoriq_cpufreq_exit);
>
> MODULE_LICENSE("GPL");
> MODULE_AUTHOR("Tang Yuantian <Yuantian.Tang at freescale.com>");
> -MODULE_DESCRIPTION("cpufreq driver for Freescale e500mc series SoCs");
> +MODULE_DESCRIPTION("cpufreq driver for Freescale QorIQ series SoCs");
+ comments from Kumar Gala :)
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