This patch moves direct control of the MPU voltage regulator out of the cpufreq driver .target callback and instead puts that logic into a clock rate change notifier callback.
The same frequency/voltage lookup via the OPP library is present, except that the calls to regulator_set_voltage are done from the clock framework instead of cpufreq. Ideally it would be nice to reduce the .target callback for OMAP's cpufreq driver to a simple call to clk_set_rate. For now there is still some other stuff needed there (jiffies per loop, rounding the rate, etc etc). Not-signed-off-by: Mike Turquette <[email protected]> --- drivers/cpufreq/omap-cpufreq.c | 154 +++++++++++++++++++++++++--------------- 1 file changed, 96 insertions(+), 58 deletions(-) diff --git a/drivers/cpufreq/omap-cpufreq.c b/drivers/cpufreq/omap-cpufreq.c index 17fa04d..bf15c49 100644 --- a/drivers/cpufreq/omap-cpufreq.c +++ b/drivers/cpufreq/omap-cpufreq.c @@ -80,10 +80,9 @@ static int omap_target(struct cpufreq_policy *policy, unsigned int relation) { unsigned int i; - int r, ret = 0; + int ret = 0; struct cpufreq_freqs freqs; - struct opp *opp; - unsigned long freq, volt = 0, volt_old = 0, tol = 0; + unsigned long freq; if (!freq_table) { dev_err(mpu_dev, "%s: cpu%d: no freq table!\n", __func__, @@ -119,47 +118,11 @@ static int omap_target(struct cpufreq_policy *policy, freq = freqs.new * 1000; - if (mpu_reg) { - opp = opp_find_freq_ceil(mpu_dev, &freq); - if (IS_ERR(opp)) { - dev_err(mpu_dev, "%s: unable to find MPU OPP for %d\n", - __func__, freqs.new); - return -EINVAL; - } - volt = opp_get_voltage(opp); - tol = volt * OPP_TOLERANCE / 100; - volt_old = regulator_get_voltage(mpu_reg); - } - - dev_dbg(mpu_dev, "cpufreq-omap: %u MHz, %ld mV --> %u MHz, %ld mV\n", - freqs.old / 1000, volt_old ? volt_old / 1000 : -1, - freqs.new / 1000, volt ? volt / 1000 : -1); - - /* scaling up? scale voltage before frequency */ - if (mpu_reg && (freqs.new > freqs.old)) { - r = regulator_set_voltage(mpu_reg, volt - tol, volt + tol); - if (r < 0) { - dev_warn(mpu_dev, "%s: unable to scale voltage up.\n", - __func__); - freqs.new = freqs.old; - goto done; - } - } + dev_dbg(mpu_dev, "cpufreq-omap: %u MHz --> %u MHz\n", + freqs.old / 1000, freqs.new / 1000); ret = clk_set_rate(mpu_clk, freqs.new * 1000); - /* scaling down? scale voltage after frequency */ - if (mpu_reg && (freqs.new < freqs.old)) { - r = regulator_set_voltage(mpu_reg, volt - tol, volt + tol); - if (r < 0) { - dev_warn(mpu_dev, "%s: unable to scale voltage down.\n", - __func__); - ret = clk_set_rate(mpu_clk, freqs.old * 1000); - freqs.new = freqs.old; - goto done; - } - } - freqs.new = omap_getspeed(policy->cpu); #ifdef CONFIG_SMP /* @@ -187,7 +150,6 @@ static int omap_target(struct cpufreq_policy *policy, freqs.new); #endif -done: /* notifiers */ for_each_cpu(i, policy->cpus) { freqs.cpu = i; @@ -207,10 +169,6 @@ static int __cpuinit omap_cpu_init(struct cpufreq_policy *policy) { int result = 0; - mpu_clk = clk_get(NULL, mpu_clk_name); - if (IS_ERR(mpu_clk)) - return PTR_ERR(mpu_clk); - if (policy->cpu >= NR_CPUS) { result = -EINVAL; goto fail_ck; @@ -284,32 +242,74 @@ static struct cpufreq_driver omap_driver = { .attr = omap_cpufreq_attr, }; -static int __init omap_cpufreq_init(void) +static int mpu_clk_volt_scale_handler(struct notifier_block *nb, + unsigned long flags, void *data) { - if (cpu_is_omap24xx()) - mpu_clk_name = "virt_prcm_set"; - else if (cpu_is_omap34xx()) - mpu_clk_name = "dpll1_ck"; - else if (cpu_is_omap44xx()) - mpu_clk_name = "dpll_mpu_ck"; + struct clk_notifier_data *cnd = data; + unsigned long tol; + int ret, volt_new, volt_old; + struct opp *opp; - if (!mpu_clk_name) { - pr_err("%s: unsupported Silicon?\n", __func__); - return -EINVAL; + volt_old = regulator_get_voltage(mpu_reg); + opp = opp_find_freq_exact(mpu_dev, cnd->new_rate, true); + volt_new = opp_get_voltage(opp); + + tol = volt_new * OPP_TOLERANCE / 100; + + /* scaling up? scale voltage before frequency */ + if (cnd->new_rate > cnd->old_rate) { + dev_dbg(mpu_dev, "cpufreq-omap: %d mV --> %d mV\n", + volt_old, volt_new); + + ret = regulator_set_voltage(mpu_reg, volt_new - tol, volt_new + tol); + + if (ret < 0) { + dev_warn(mpu_dev, "%s: unable to scale voltage up.\n", + __func__); + return NOTIFY_BAD; + } + } + + /* scaling down? scale voltage after frequency */ + if (cnd->new_rate < cnd->old_rate) { + dev_dbg(mpu_dev, "cpufreq-omap: %d mV --> %d mV\n", + volt_old, volt_new); + + ret = regulator_set_voltage(mpu_reg, volt_new - tol, volt_new + tol); + + if (ret< 0) { + dev_warn(mpu_dev, "%s: unable to scale voltage down.\n", + __func__); + return NOTIFY_BAD; + } } + return NOTIFY_OK; +} + +static struct notifier_block mpu_clk_volt_scale_nb = { + .notifier_call = mpu_clk_volt_scale_handler, +}; + +static int __init omap_regulator_init(void) +{ + int ret = 0; + mpu_dev = omap_device_get_by_hwmod_name("mpu"); if (!mpu_dev) { pr_warning("%s: unable to get the mpu device\n", __func__); - return -EINVAL; + ret = -EINVAL; + goto out; } mpu_reg = regulator_get(mpu_dev, "vcc"); if (IS_ERR(mpu_reg)) { pr_warning("%s: unable to get MPU regulator\n", __func__); mpu_reg = NULL; + ret = -ENODEV; + goto out; } else { - /* + /* * Ensure physical regulator is present. * (e.g. could be dummy regulator.) */ @@ -318,9 +318,47 @@ static int __init omap_cpufreq_init(void) __func__); regulator_put(mpu_reg); mpu_reg = NULL; + ret = -ENODEV; + goto out; } } +out: + return ret; +} + +static int __init omap_cpufreq_init(void) +{ + int ret; + + if (cpu_is_omap24xx()) + mpu_clk_name = "virt_prcm_set"; + else if (cpu_is_omap34xx()) + mpu_clk_name = "dpll1_ck"; + else if (cpu_is_omap44xx()) + mpu_clk_name = "dpll_mpu_ck"; + + if (!mpu_clk_name) { + pr_err("%s: unsupported Silicon?\n", __func__); + return -EINVAL; + } + + mpu_clk = clk_get(NULL, mpu_clk_name); + if (IS_ERR(mpu_clk)) + return PTR_ERR(mpu_clk); + + ret = omap_regulator_init(); + if (ret) { + pr_err("%s: failed to get mpu regulator\n", __func__); + pr_err("%s: skipping clk notifier registration\n", __func__); + goto out; + } + + ret = clk_notifier_register(mpu_clk, &mpu_clk_volt_scale_nb); + if (ret) + pr_err("%s: failed to register clk notifier\n", __func__); + +out: return cpufreq_register_driver(&omap_driver); } -- 1.7.9.5 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
