From patchwork Mon Dec 12 03:42:27 2011 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Subject: [2/7] arm/imx: cpufreq: add multi-core support Date: Sun, 11 Dec 2011 17:42:27 -0000 From: Richard Zhao X-Patchwork-Id: 130630 Message-Id: <1323661352-10291-3-git-send-email-richard.zhao@linaro.org> To: Cc: fabio.estevam@freescale.com, patches@linaro.org, eric.miao@linaro.org, kernel@pengutronix.de, shawn.guo@linaro.org, Richard Zhao Signed-off-by: Richard Zhao --- arch/arm/plat-mxc/cpufreq.c | 99 ++++++++++++++++++++++++++++-------------- 1 files changed, 66 insertions(+), 33 deletions(-) diff --git a/arch/arm/plat-mxc/cpufreq.c b/arch/arm/plat-mxc/cpufreq.c index 74aac96..122b21a 100644 --- a/arch/arm/plat-mxc/cpufreq.c +++ b/arch/arm/plat-mxc/cpufreq.c @@ -21,6 +21,7 @@ #include #include #include +#include #include #include @@ -33,6 +34,7 @@ static int cpu_freq_khz_min; static int cpu_freq_khz_max; static struct clk *cpu_clk; +static DEFINE_MUTEX(cpu_lock); static struct cpufreq_frequency_table *imx_freq_table; static int cpu_op_nr; @@ -58,17 +60,11 @@ static int set_cpu_freq(int freq) static int mxc_verify_speed(struct cpufreq_policy *policy) { - if (policy->cpu != 0) - return -EINVAL; - return cpufreq_frequency_table_verify(policy, imx_freq_table); } static unsigned int mxc_get_speed(unsigned int cpu) { - if (cpu) - return 0; - return clk_get_rate(cpu_clk) / 1000; } @@ -76,23 +72,49 @@ static int mxc_set_target(struct cpufreq_policy *policy, unsigned int target_freq, unsigned int relation) { struct cpufreq_freqs freqs; - int freq_Hz; + int freq_Hz, cpu; int ret = 0; unsigned int index; + mutex_lock(&cpu_lock); + cpufreq_frequency_table_target(policy, imx_freq_table, target_freq, relation, &index); freq_Hz = imx_freq_table[index].frequency * 1000; freqs.old = clk_get_rate(cpu_clk) / 1000; - freqs.new = freq_Hz / 1000; - freqs.cpu = 0; + freqs.new = clk_round_rate(cpu_clk, freq_Hz); + freqs.new = (freqs.new ? freqs.new : freq_Hz) / 1000; freqs.flags = 0; - cpufreq_notify_transition(&freqs, CPUFREQ_PRECHANGE); + + if (freqs.old == freqs.new) { + mutex_unlock(&cpu_lock); + return 0; + } + + for_each_possible_cpu(cpu) { + freqs.cpu = cpu; + cpufreq_notify_transition(&freqs, CPUFREQ_PRECHANGE); + } ret = set_cpu_freq(freq_Hz); - cpufreq_notify_transition(&freqs, CPUFREQ_POSTCHANGE); +#ifdef CONFIG_SMP + /* loops_per_jiffy is not updated by the cpufreq core for SMP systems. + * So update it for all CPUs. + */ + for_each_possible_cpu(cpu) + per_cpu(cpu_data, cpu).loops_per_jiffy = + cpufreq_scale(per_cpu(cpu_data, cpu).loops_per_jiffy, + freqs.old, freqs.new); +#endif + + for_each_possible_cpu(cpu) { + freqs.cpu = cpu; + cpufreq_notify_transition(&freqs, CPUFREQ_POSTCHANGE); + } + + mutex_unlock(&cpu_lock); return ret; } @@ -104,7 +126,7 @@ static int __init mxc_cpufreq_init(struct cpufreq_policy *policy) printk(KERN_INFO "i.MXC CPU frequency driver\n"); - if (policy->cpu != 0) + if (policy->cpu >= num_possible_cpus()) return -EINVAL; if (!get_cpu_op) @@ -116,37 +138,45 @@ static int __init mxc_cpufreq_init(struct cpufreq_policy *policy) return PTR_ERR(cpu_clk); } - cpu_op_tbl = get_cpu_op(&cpu_op_nr); + mutex_lock(&cpu_lock); + if (!imx_freq_table) { + cpu_op_tbl = get_cpu_op(&cpu_op_nr); - cpu_freq_khz_min = cpu_op_tbl[0].cpu_rate / 1000; - cpu_freq_khz_max = cpu_op_tbl[0].cpu_rate / 1000; + cpu_freq_khz_min = cpu_op_tbl[0].cpu_rate / 1000; + cpu_freq_khz_max = cpu_op_tbl[0].cpu_rate / 1000; - imx_freq_table = kmalloc( - sizeof(struct cpufreq_frequency_table) * (cpu_op_nr + 1), - GFP_KERNEL); - if (!imx_freq_table) { - ret = -ENOMEM; - goto err1; - } + imx_freq_table = kmalloc(sizeof(struct cpufreq_frequency_table) + * (cpu_op_nr + 1), GFP_KERNEL); + if (!imx_freq_table) { + ret = -ENOMEM; + mutex_unlock(&cpu_lock); + goto err1; + } - for (i = 0; i < cpu_op_nr; i++) { - imx_freq_table[i].index = i; - imx_freq_table[i].frequency = cpu_op_tbl[i].cpu_rate / 1000; + for (i = 0; i < cpu_op_nr; i++) { + imx_freq_table[i].index = i; + imx_freq_table[i].frequency = + cpu_op_tbl[i].cpu_rate / 1000; - if ((cpu_op_tbl[i].cpu_rate / 1000) < cpu_freq_khz_min) - cpu_freq_khz_min = cpu_op_tbl[i].cpu_rate / 1000; + if ((cpu_op_tbl[i].cpu_rate / 1000) < cpu_freq_khz_min) + cpu_freq_khz_min = + cpu_op_tbl[i].cpu_rate / 1000; - if ((cpu_op_tbl[i].cpu_rate / 1000) > cpu_freq_khz_max) - cpu_freq_khz_max = cpu_op_tbl[i].cpu_rate / 1000; - } + if ((cpu_op_tbl[i].cpu_rate / 1000) > cpu_freq_khz_max) + cpu_freq_khz_max = + cpu_op_tbl[i].cpu_rate / 1000; + } - imx_freq_table[i].index = i; - imx_freq_table[i].frequency = CPUFREQ_TABLE_END; + imx_freq_table[i].index = i; + imx_freq_table[i].frequency = CPUFREQ_TABLE_END; + } + mutex_unlock(&cpu_lock); policy->cur = clk_get_rate(cpu_clk) / 1000; policy->min = policy->cpuinfo.min_freq = cpu_freq_khz_min; policy->max = policy->cpuinfo.max_freq = cpu_freq_khz_max; - + policy->shared_type = CPUFREQ_SHARED_TYPE_ANY; + cpumask_setall(policy->cpus); /* Manual states, that PLL stabilizes in two CLK32 periods */ policy->cpuinfo.transition_latency = 2 * NANOSECOND / CLK32_FREQ; @@ -173,7 +203,10 @@ static int mxc_cpufreq_exit(struct cpufreq_policy *policy) set_cpu_freq(cpu_freq_khz_max * 1000); clk_put(cpu_clk); + mutex_lock(&cpu_lock); kfree(imx_freq_table); + imx_freq_table = NULL; + mutex_unlock(&cpu_lock); return 0; }