From 848cb944213e88e4929a7efcc1c92bb6b6445353 Mon Sep 17 00:00:00 2001 From: Hans-Christian Egtvedt Date: Mon, 16 Sep 2013 18:56:41 +0530 Subject: cpufreq: at32ap: add frequency table This patch adds a dynamically calculated frequency table to the at32ap driver. In short the architecture can scale in power of two between a maximum and minimum frequency. Min, max, and the steps in between are added to the table. Signed-off-by: Hans-Christian Egtvedt Signed-off-by: Viresh Kumar Signed-off-by: Rafael J. Wysocki --- drivers/cpufreq/at32ap-cpufreq.c | 49 +++++++++++++++++++++++++++++++++++++--- 1 file changed, 46 insertions(+), 3 deletions(-) (limited to 'drivers/cpufreq/at32ap-cpufreq.c') diff --git a/drivers/cpufreq/at32ap-cpufreq.c b/drivers/cpufreq/at32ap-cpufreq.c index e0c38d938997..1d19fa59bc2c 100644 --- a/drivers/cpufreq/at32ap-cpufreq.c +++ b/drivers/cpufreq/at32ap-cpufreq.c @@ -19,8 +19,10 @@ #include #include #include +#include static struct clk *cpuclk; +static struct cpufreq_frequency_table *freq_table; static int at32_verify_speed(struct cpufreq_policy *policy) { @@ -85,13 +87,17 @@ static int at32_set_target(struct cpufreq_policy *policy, static int __init at32_cpufreq_driver_init(struct cpufreq_policy *policy) { + unsigned int frequency, rate; + int retval, steps, i; + if (policy->cpu != 0) return -EINVAL; cpuclk = clk_get(NULL, "cpu"); if (IS_ERR(cpuclk)) { pr_debug("cpufreq: could not get CPU clk\n"); - return PTR_ERR(cpuclk); + retval = PTR_ERR(cpuclk); + goto out_err; } policy->cpuinfo.min_freq = (clk_round_rate(cpuclk, 1) + 500) / 1000; @@ -101,9 +107,46 @@ static int __init at32_cpufreq_driver_init(struct cpufreq_policy *policy) policy->min = policy->cpuinfo.min_freq; policy->max = policy->cpuinfo.max_freq; - printk("cpufreq: AT32AP CPU frequency driver\n"); + /* + * AVR32 CPU frequency rate scales in power of two between maximum and + * minimum, also add space for the table end marker. + * + * Further validate that the frequency is usable, and append it to the + * frequency table. + */ + steps = fls(policy->cpuinfo.max_freq / policy->cpuinfo.min_freq) + 1; + freq_table = kzalloc(steps * sizeof(struct cpufreq_frequency_table), + GFP_KERNEL); + if (!freq_table) { + retval = -ENOMEM; + goto out_err_put_clk; + } - return 0; + frequency = policy->cpuinfo.max_freq; + for (i = 0; i < (steps - 1); i++) { + rate = clk_round_rate(cpuclk, frequency * 1000) / 1000; + + if (rate != frequency) + freq_table[i].frequency = CPUFREQ_ENTRY_INVALID; + else + freq_table[i].frequency = frequency; + + frequency /= 2; + } + + freq_table[steps - 1].frequency = CPUFREQ_TABLE_END; + + retval = cpufreq_table_validate_and_show(policy, freq_table); + if (!retval) { + printk("cpufreq: AT32AP CPU frequency driver\n"); + return 0; + } + + kfree(freq_table); +out_err_put_clk: + clk_put(cpuclk); +out_err: + return retval; } static struct cpufreq_driver at32_driver = { -- cgit v1.2.3 From 5ae68f4737cec20505f3bb0a99bcb2efcfd66792 Mon Sep 17 00:00:00 2001 From: Viresh Kumar Date: Thu, 3 Oct 2013 20:27:58 +0530 Subject: cpufreq: at32ap: Use generic cpufreq routines Most of the CPUFreq drivers do similar things in .exit() and .verify() routines and .attr. So its better if we have generic routines for them which can be used by cpufreq drivers then. This patch uses these generic routines in the at32ap driver. Acked-by: Hans-Christian Egtvedt Signed-off-by: Viresh Kumar Signed-off-by: Rafael J. Wysocki --- drivers/cpufreq/at32ap-cpufreq.c | 12 +----------- 1 file changed, 1 insertion(+), 11 deletions(-) (limited to 'drivers/cpufreq/at32ap-cpufreq.c') diff --git a/drivers/cpufreq/at32ap-cpufreq.c b/drivers/cpufreq/at32ap-cpufreq.c index 1d19fa59bc2c..788f7e77565d 100644 --- a/drivers/cpufreq/at32ap-cpufreq.c +++ b/drivers/cpufreq/at32ap-cpufreq.c @@ -24,16 +24,6 @@ static struct clk *cpuclk; static struct cpufreq_frequency_table *freq_table; -static int at32_verify_speed(struct cpufreq_policy *policy) -{ - if (policy->cpu != 0) - return -EINVAL; - - cpufreq_verify_within_limits(policy, policy->cpuinfo.min_freq, - policy->cpuinfo.max_freq); - return 0; -} - static unsigned int at32_get_speed(unsigned int cpu) { /* No SMP support */ @@ -152,7 +142,7 @@ out_err: static struct cpufreq_driver at32_driver = { .name = "at32ap", .init = at32_cpufreq_driver_init, - .verify = at32_verify_speed, + .verify = cpufreq_generic_frequency_table_verify, .target = at32_set_target, .get = at32_get_speed, .flags = CPUFREQ_STICKY, -- cgit v1.2.3 From 017189b51e0eecd58cf4f65f6f16d59dae6c1368 Mon Sep 17 00:00:00 2001 From: Viresh Kumar Date: Thu, 3 Oct 2013 20:28:33 +0530 Subject: cpufreq: at32ap: don't initialize part of policy set by core Many common initializations of struct policy are moved to core now and hence this driver doesn't need to do it. This patch removes such code. Most recent of those changes is to call ->get() in the core after calling ->init(). Acked-by: Hans-Christian Egtvedt Signed-off-by: Viresh Kumar Signed-off-by: Rafael J. Wysocki --- drivers/cpufreq/at32ap-cpufreq.c | 12 ++++-------- 1 file changed, 4 insertions(+), 8 deletions(-) (limited to 'drivers/cpufreq/at32ap-cpufreq.c') diff --git a/drivers/cpufreq/at32ap-cpufreq.c b/drivers/cpufreq/at32ap-cpufreq.c index 788f7e77565d..7439deddd5cf 100644 --- a/drivers/cpufreq/at32ap-cpufreq.c +++ b/drivers/cpufreq/at32ap-cpufreq.c @@ -77,7 +77,7 @@ static int at32_set_target(struct cpufreq_policy *policy, static int __init at32_cpufreq_driver_init(struct cpufreq_policy *policy) { - unsigned int frequency, rate; + unsigned int frequency, rate, min_freq; int retval, steps, i; if (policy->cpu != 0) @@ -90,12 +90,9 @@ static int __init at32_cpufreq_driver_init(struct cpufreq_policy *policy) goto out_err; } - policy->cpuinfo.min_freq = (clk_round_rate(cpuclk, 1) + 500) / 1000; - policy->cpuinfo.max_freq = (clk_round_rate(cpuclk, ~0UL) + 500) / 1000; + min_freq = (clk_round_rate(cpuclk, 1) + 500) / 1000; + frequency = (clk_round_rate(cpuclk, ~0UL) + 500) / 1000; policy->cpuinfo.transition_latency = 0; - policy->cur = at32_get_speed(0); - policy->min = policy->cpuinfo.min_freq; - policy->max = policy->cpuinfo.max_freq; /* * AVR32 CPU frequency rate scales in power of two between maximum and @@ -104,7 +101,7 @@ static int __init at32_cpufreq_driver_init(struct cpufreq_policy *policy) * Further validate that the frequency is usable, and append it to the * frequency table. */ - steps = fls(policy->cpuinfo.max_freq / policy->cpuinfo.min_freq) + 1; + steps = fls(frequency / min_freq) + 1; freq_table = kzalloc(steps * sizeof(struct cpufreq_frequency_table), GFP_KERNEL); if (!freq_table) { @@ -112,7 +109,6 @@ static int __init at32_cpufreq_driver_init(struct cpufreq_policy *policy) goto out_err_put_clk; } - frequency = policy->cpuinfo.max_freq; for (i = 0; i < (steps - 1); i++) { rate = clk_round_rate(cpuclk, frequency * 1000) / 1000; -- cgit v1.2.3 From 9c0ebcf78fde0ffa348a95a544c6d3f2dac5af65 Mon Sep 17 00:00:00 2001 From: Viresh Kumar Date: Fri, 25 Oct 2013 19:45:48 +0530 Subject: cpufreq: Implement light weight ->target_index() routine Currently, the prototype of cpufreq_drivers target routines is: int target(struct cpufreq_policy *policy, unsigned int target_freq, unsigned int relation); And most of the drivers call cpufreq_frequency_table_target() to get a valid index of their frequency table which is closest to the target_freq. And they don't use target_freq and relation after that. So, it makes sense to just do this work in cpufreq core before calling cpufreq_frequency_table_target() and simply pass index instead. But this can be done only with drivers which expose their frequency table with cpufreq core. For others we need to stick with the old prototype of target() until those drivers are converted to expose frequency tables. This patch implements the new light weight prototype for target_index() routine. It looks like this: int target_index(struct cpufreq_policy *policy, unsigned int index); CPUFreq core will call cpufreq_frequency_table_target() before calling this routine and pass index to it. Because CPUFreq core now requires to call routines present in freq_table.c CONFIG_CPU_FREQ_TABLE must be enabled all the time. This also marks target() interface as deprecated. So, that new drivers avoid using it. And Documentation is updated accordingly. It also converts existing .target() to newly defined light weight .target_index() routine for many driver. Acked-by: Hans-Christian Egtvedt Acked-by: Jesper Nilsson Acked-by: Linus Walleij Acked-by: Russell King Acked-by: David S. Miller Tested-by: Andrew Lunn Signed-off-by: Viresh Kumar Signed-off-by: Rafael J. Wysocki --- drivers/cpufreq/at32ap-cpufreq.c | 23 +++++------------------ 1 file changed, 5 insertions(+), 18 deletions(-) (limited to 'drivers/cpufreq/at32ap-cpufreq.c') diff --git a/drivers/cpufreq/at32ap-cpufreq.c b/drivers/cpufreq/at32ap-cpufreq.c index 7439deddd5cf..81d07527bde6 100644 --- a/drivers/cpufreq/at32ap-cpufreq.c +++ b/drivers/cpufreq/at32ap-cpufreq.c @@ -35,25 +35,12 @@ static unsigned int at32_get_speed(unsigned int cpu) static unsigned int ref_freq; static unsigned long loops_per_jiffy_ref; -static int at32_set_target(struct cpufreq_policy *policy, - unsigned int target_freq, - unsigned int relation) +static int at32_set_target(struct cpufreq_policy *policy, unsigned int index) { struct cpufreq_freqs freqs; - long freq; - - /* Convert target_freq from kHz to Hz */ - freq = clk_round_rate(cpuclk, target_freq * 1000); - - /* Check if policy->min <= new_freq <= policy->max */ - if(freq < (policy->min * 1000) || freq > (policy->max * 1000)) - return -EINVAL; - - pr_debug("cpufreq: requested frequency %u Hz\n", target_freq * 1000); freqs.old = at32_get_speed(0); - freqs.new = (freq + 500) / 1000; - freqs.flags = 0; + freqs.new = freq_table[index].frequency; if (!ref_freq) { ref_freq = freqs.old; @@ -64,13 +51,13 @@ static int at32_set_target(struct cpufreq_policy *policy, if (freqs.old < freqs.new) boot_cpu_data.loops_per_jiffy = cpufreq_scale( loops_per_jiffy_ref, ref_freq, freqs.new); - clk_set_rate(cpuclk, freq); + clk_set_rate(cpuclk, freqs.new * 1000); if (freqs.new < freqs.old) boot_cpu_data.loops_per_jiffy = cpufreq_scale( loops_per_jiffy_ref, ref_freq, freqs.new); cpufreq_notify_transition(policy, &freqs, CPUFREQ_POSTCHANGE); - pr_debug("cpufreq: set frequency %lu Hz\n", freq); + pr_debug("cpufreq: set frequency %u Hz\n", freqs.new * 1000); return 0; } @@ -139,7 +126,7 @@ static struct cpufreq_driver at32_driver = { .name = "at32ap", .init = at32_cpufreq_driver_init, .verify = cpufreq_generic_frequency_table_verify, - .target = at32_set_target, + .target_index = at32_set_target, .get = at32_get_speed, .flags = CPUFREQ_STICKY, }; -- cgit v1.2.3 From d4019f0a92ab802f385cc9c8ad3ab7b5449712cb Mon Sep 17 00:00:00 2001 From: Viresh Kumar Date: Wed, 14 Aug 2013 19:38:24 +0530 Subject: cpufreq: move freq change notifications to cpufreq core Most of the drivers do following in their ->target_index() routines: struct cpufreq_freqs freqs; freqs.old = old freq... freqs.new = new freq... cpufreq_notify_transition(policy, &freqs, CPUFREQ_PRECHANGE); /* Change rate here */ cpufreq_notify_transition(policy, &freqs, CPUFREQ_POSTCHANGE); This is replicated over all cpufreq drivers today and there doesn't exists a good enough reason why this shouldn't be moved to cpufreq core instead. There are few special cases though, like exynos5440, which doesn't do everything on the call to ->target_index() routine and call some kind of bottom halves for doing this work, work/tasklet/etc.. They may continue doing notification from their own code as flag: CPUFREQ_ASYNC_NOTIFICATION is already set for them. All drivers are also modified in this patch to avoid breaking 'git bisect', as double notification would happen otherwise. Acked-by: Hans-Christian Egtvedt Acked-by: Jesper Nilsson Acked-by: Linus Walleij Acked-by: Russell King Acked-by: Stephen Warren Tested-by: Andrew Lunn Tested-by: Nicolas Pitre Reviewed-by: Lan Tianyu Signed-off-by: Viresh Kumar Signed-off-by: Rafael J. Wysocki --- drivers/cpufreq/at32ap-cpufreq.c | 22 +++++++++------------- 1 file changed, 9 insertions(+), 13 deletions(-) (limited to 'drivers/cpufreq/at32ap-cpufreq.c') diff --git a/drivers/cpufreq/at32ap-cpufreq.c b/drivers/cpufreq/at32ap-cpufreq.c index 81d07527bde6..856ad80418ae 100644 --- a/drivers/cpufreq/at32ap-cpufreq.c +++ b/drivers/cpufreq/at32ap-cpufreq.c @@ -37,27 +37,23 @@ static unsigned long loops_per_jiffy_ref; static int at32_set_target(struct cpufreq_policy *policy, unsigned int index) { - struct cpufreq_freqs freqs; + unsigned int old_freq, new_freq; - freqs.old = at32_get_speed(0); - freqs.new = freq_table[index].frequency; + old_freq = at32_get_speed(0); + new_freq = freq_table[index].frequency; if (!ref_freq) { - ref_freq = freqs.old; + ref_freq = old_freq; loops_per_jiffy_ref = boot_cpu_data.loops_per_jiffy; } - cpufreq_notify_transition(policy, &freqs, CPUFREQ_PRECHANGE); - if (freqs.old < freqs.new) + if (old_freq < new_freq) boot_cpu_data.loops_per_jiffy = cpufreq_scale( - loops_per_jiffy_ref, ref_freq, freqs.new); - clk_set_rate(cpuclk, freqs.new * 1000); - if (freqs.new < freqs.old) + loops_per_jiffy_ref, ref_freq, new_freq); + clk_set_rate(cpuclk, new_freq * 1000); + if (new_freq < old_freq) boot_cpu_data.loops_per_jiffy = cpufreq_scale( - loops_per_jiffy_ref, ref_freq, freqs.new); - cpufreq_notify_transition(policy, &freqs, CPUFREQ_POSTCHANGE); - - pr_debug("cpufreq: set frequency %u Hz\n", freqs.new * 1000); + loops_per_jiffy_ref, ref_freq, new_freq); return 0; } -- cgit v1.2.3