On 20 January 2015 at 00:00, Mike Turquette mturquette@linaro.org wrote:
Quoting pi-cheng.chen (2015-01-09 01:54:51)
diff --git a/drivers/cpufreq/mt8173-cpufreq.c b/drivers/cpufreq/mt8173-cpufreq.c new file mode 100644 index 0000000..b578c10 --- /dev/null +++ b/drivers/cpufreq/mt8173-cpufreq.c @@ -0,0 +1,459 @@
Hello Mike,
Hello Pi-Cheng,
<snip>
+#include <linux/module.h> +#include <linux/of.h> +#include <linux/of_address.h> +#include <linux/platform_device.h> +#include <linux/cpufreq.h> +#include <linux/cpufreq-dt.h> +#include <linux/cpumask.h> +#include <linux/slab.h> +#include <linux/clk.h> +#include <linux/clk-provider.h>
I'll echo what Viresh said here. CPUfreq drivers should typically be clock consumers and only require clk.h, not clk-provider.h. More on that below.
I included it because of the __clk_lookup call. But yes, I will use the clk_get to get the intermediate clock to get rid of this.
<snip>
+static void cpuclk_mux_set(int cluster, u32 sel) +{
u32 val;u32 mask = 0x3;if (cluster == BIG_CLUSTER) {mask <<= 2;sel <<= 2;}spin_lock(&lock);val = readl(clk_mux_regs);val = (val & ~mask) | sel;writel(val, clk_mux_regs);spin_unlock(&lock);+}
Is cpuclk a mux that is represented in the MT8173 clock driver? It looks like a clock that belong to the clock driver, but this cpufreq driver is writing to that register directly.
Yes, it's a mux but not presented in MT8173 clock driver yet. Therefore I map the HW register and writing them directly to do reparent. I will get rid of it once I got those muxes presented in MT8173 clock driver.
<snip>
+static int mt8173_cpufreq_dvfs_info_init(void) +{
<snip>
mainpll = __clk_lookup("mainpll");if (!mainpll) {pr_err("failed to get mainpll clk\n");ret = -ENOENT;goto dvfs_info_release;}mainpll_freq = clk_get_rate(mainpll);This is definitely bad. Why not use clk_get() here? __clk_lookup should not be exposed to clock consumer drivers (and I hope to get rid of it completely some day).
Thanks for pointing me out the right API to do it. I will fix it in next version.
Best Regards, Pi-Cheng
Regards, Mike