On 12.01.2023 16:37, Bjorn Andersson wrote:
> On Wed, Jan 11, 2023 at 09:51:25PM +0100, Konrad Dybcio wrote:
>> In preparation for CPRh-aware OSM programming, change the probe
>> function so that we determine the number of frequency domains by
>> counting the number of reg-names entries that begin with
>> "freq-domain", as the aforementioned changes require introduction
>> of non-freq-domain register spaces.
>>
>
> Requiring reg-names would break backwards compatibility with at least
> sc7280 and sm6115.
Ouch, you're correct..
Does checking for reg-names and applying the code flow proposed in this
patch if found and the existing one if not sound good?
Konrad
>
> Regards,
> Bjorn
>
>> Fixes: 1a6a8b0080b0 ("cpufreq: qcom-hw: Fix reading "reg" with address/size-cells != 2")
>> Fixes: 054a3ef683a1 ("cpufreq: qcom-hw: Allocate qcom_cpufreq_data during probe")
>> Signed-off-by: Konrad Dybcio <konrad.dybcio@xxxxxxxxxx>
>> ---
>> drivers/cpufreq/qcom-cpufreq-hw.c | 34 ++++++++++++++++++++++---------
>> 1 file changed, 24 insertions(+), 10 deletions(-)
>>
>> diff --git a/drivers/cpufreq/qcom-cpufreq-hw.c b/drivers/cpufreq/qcom-cpufreq-hw.c
>> index 9505a812d6a1..89d5ed267399 100644
>> --- a/drivers/cpufreq/qcom-cpufreq-hw.c
>> +++ b/drivers/cpufreq/qcom-cpufreq-hw.c
>> @@ -651,8 +651,9 @@ static int qcom_cpufreq_hw_driver_probe(struct platform_device *pdev)
>> struct device *dev = &pdev->dev;
>> struct device_node *soc_node;
>> struct device *cpu_dev;
>> + const char *reg_name;
>> struct clk *clk;
>> - int ret, i, num_domains, reg_sz;
>> + int ret, i, num_reg_names, num_domains = 0;
>>
>> clk = clk_get(dev, "xo");
>> if (IS_ERR(clk))
>> @@ -684,19 +685,32 @@ static int qcom_cpufreq_hw_driver_probe(struct platform_device *pdev)
>> if (!soc_node)
>> return -EINVAL;
>>
>> - ret = of_property_read_u32(soc_node, "#address-cells", ®_sz);
>> - if (ret)
>> + num_reg_names = of_property_count_strings(dev->of_node, "reg-names");
>> + if (num_reg_names <= 0) {
>> + ret = num_reg_names ? num_reg_names : -ENODATA;
>> goto of_exit;
>> + }
>>
>> - ret = of_property_read_u32(soc_node, "#size-cells", &i);
>> - if (ret)
>> - goto of_exit;
>> + for (i = 0; i < num_reg_names; i++) {
>> + ret = of_property_read_string_index(dev->of_node, "reg-names", i, ®_name);
>> + if (ret < 0)
>> + goto of_exit;
>>
>> - reg_sz += i;
>> + /*
>> + * Check if the i-th reg is a freq-domain base, no need to add 1
>> + * more byte for idx, as sizeof counts \0 whereas strlen does not.
>> + */
>> + if (strlen(reg_name) == sizeof("freq-domain")) {
>> + /* Check if this reg-name begins with "freq-domain" */
>> + if (!strncmp(reg_name, "freq-domain", sizeof("freq-domain") - 1))
>> + num_domains++;
>> + }
>> + }
>>
>> - num_domains = of_property_count_elems_of_size(dev->of_node, "reg", sizeof(u32) * reg_sz);
>> - if (num_domains <= 0)
>> - return num_domains;
>> + if (num_domains <= 0) {
>> + ret = -EINVAL;
>> + goto of_exit;
>> + }
>>
>> qcom_cpufreq.data = devm_kzalloc(dev, sizeof(struct qcom_cpufreq_data) * num_domains,
>> GFP_KERNEL);
>> --
>> 2.39.0
>>
