[PATCH 2/2] cpufreq: add cpufreq driver for Mediatek MT8173 SoC
From: Mike Turquette <hidden>
Date: 2015-01-19 16:00:52
Also in:
linux-pm, lkml
Quoting pi-cheng.chen (2015-01-09 01:54:51)
quoted hunk ↗ jump to hunk
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 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. <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. <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). Regards, Mike