Re: [PATCH v2 1/2] PM / OPP: Allow boost frequency to be looked up from device tree

Nishanth Menon
2014-02-07T15:52:07Z

On 02/07/2014 09:38 AM, Thomas Abraham wrote:
[...]
>>> diff --git a/drivers/base/power/opp.c b/drivers/base/power/opp.c
>>> index fa41874..b636826 100644
>>> --- a/drivers/base/power/opp.c
>>> +++ b/drivers/base/power/opp.c
>>> @@ -628,7 +628,8 @@ int dev_pm_opp_init_cpufreq_table(struct device *dev,
>>> struct device_opp *dev_opp;
>>> struct dev_pm_opp *opp;
>>> struct cpufreq_frequency_table *freq_table;
>>> - int i = 0;
>>> + int i = 0, j, len, ret;
>>> + u32 *boost_freqs = NULL;
>>>
>>> /* Pretend as if I am an updater */
>>> mutex_lock(&dev_opp_list_lock);
>>> @@ -650,10 +651,35 @@ int dev_pm_opp_init_cpufreq_table(struct device *dev,
>>> return -ENOMEM;
>>> }
>>>
>>> + if (of_find_property(dev->of_node, "boost-frequency", &len)) {
>>> + if (len == 0 || (len & (sizeof(u32) - 1)) != 0) {
>>> + dev_err(dev, "%s: invalid boost frequency\n", __func__);
>>> + ret = -EINVAL;
>>> + goto err_boost;
>>> + }
>>> +
>>> + boost_freqs = kzalloc(len, GFP_KERNEL);
>>> + if (!boost_freqs) {
>>> + dev_warn(dev, "%s: no memory for boost freq table\n",
>>> + __func__);
>>> + ret = -ENOMEM;
>>> + goto err_boost;
>>> + }
>>> + of_property_read_u32_array(dev->of_node, "boost-frequency",
>>> + boost_freqs, len / sizeof(u32));
>>> + }
>>> +
>>> list_for_each_entry(opp, &dev_opp->opp_list, node) {
>>> if (opp->available) {
>>> freq_table[i].driver_data = i;
>>> freq_table[i].frequency = opp->rate / 1000;
>>> + for (j = 0; j < len / sizeof(u32) && boost_freqs; j++) {
>>> + if (boost_freqs[j] == freq_table[i].frequency) {
>>> + freq_table[i].driver_data =
>>> + CPUFREQ_BOOST_FREQ;
>>> + break;
>>> + }
>>> + }
>>
>> What if any one of the boost_freqs are not contained in the enabled frequencies?
>
> It is not used as a boost frequency because its corresponding voltage
> is not known. If required a warning can be printed out for the same.

yes - that would be good, as it helps debug if there are developer
errors in dts.

--
Regards,
Nishanth Menon