Commit b89c01c9 authored Aug 24, 2020 by Jon Hunter Committed by Viresh Kumar Sep 16, 2020

cpufreq: tegra186: Fix initial frequency

Commit 6cc3d0e9 ("cpufreq: tegra186: add
CPUFREQ_NEED_INITIAL_FREQ_CHECK flag") fixed CPUFREQ support for
Tegra186 but as a consequence the following warnings are now seen on
boot ...

cpufreq: cpufreq_online: CPU0: Running at unlisted freq: 0 KHz
cpufreq: cpufreq_online: CPU0: Unlisted initial frequency changed to: 2035200 KHz
cpufreq: cpufreq_online: CPU1: Running at unlisted freq: 0 KHz
cpufreq: cpufreq_online: CPU1: Unlisted initial frequency changed to: 2035200 KHz
cpufreq: cpufreq_online: CPU2: Running at unlisted freq: 0 KHz
cpufreq: cpufreq_online: CPU2: Unlisted initial frequency changed to: 2035200 KHz
cpufreq: cpufreq_online: CPU3: Running at unlisted freq: 0 KHz
cpufreq: cpufreq_online: CPU3: Unlisted initial frequency changed to: 2035200 KHz
cpufreq: cpufreq_online: CPU4: Running at unlisted freq: 0 KHz
cpufreq: cpufreq_online: CPU4: Unlisted initial frequency changed to: 2035200 KHz
cpufreq: cpufreq_online: CPU5: Running at unlisted freq: 0 KHz
cpufreq: cpufreq_online: CPU5: Unlisted initial frequency changed to: 2035200 KHz

Fix this by adding a 'get' callback for the Tegra186 CPUFREQ driver to
retrieve the current operating frequency for a given CPU. The 'get'
callback uses the current 'ndiv' value that is programmed to determine
that current operating frequency.

Signed-off-by: Jon Hunter <jonathanh@nvidia.com>
[ Viresh: Return 0 on error ]
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>

parent b1593e53

drivers/cpufreq/tegra186-cpufreq.c

+30 −0

Original line number	Diff line number	Diff line
		@@ -14,6 +14,7 @@

		#define EDVD_CORE_VOLT_FREQ(core) (0x20 + (core) * 0x4)
		#define EDVD_CORE_VOLT_FREQ_F_SHIFT 0
		#define EDVD_CORE_VOLT_FREQ_F_MASK 0xffff
		#define EDVD_CORE_VOLT_FREQ_V_SHIFT 16

		struct tegra186_cpufreq_cluster_info {
		@@ -91,10 +92,39 @@ static int tegra186_cpufreq_set_target(struct cpufreq_policy *policy,
		return 0;
		}

		static unsigned int tegra186_cpufreq_get(unsigned int cpu)
		{
		struct cpufreq_frequency_table *tbl;
		struct cpufreq_policy *policy;
		void __iomem *edvd_reg;
		unsigned int i, freq = 0;
		u32 ndiv;

		policy = cpufreq_cpu_get(cpu);
		if (!policy)
		return 0;

		tbl = policy->freq_table;
		edvd_reg = policy->driver_data;
		ndiv = readl(edvd_reg) & EDVD_CORE_VOLT_FREQ_F_MASK;

		for (i = 0; tbl[i].frequency != CPUFREQ_TABLE_END; i++) {
		if ((tbl[i].driver_data & EDVD_CORE_VOLT_FREQ_F_MASK) == ndiv) {
		freq = tbl[i].frequency;
		break;
		}
		}

		cpufreq_cpu_put(policy);

		return freq;
		}

		static struct cpufreq_driver tegra186_cpufreq_driver = {
		.name = "tegra186",
		.flags = CPUFREQ_STICKY \| CPUFREQ_HAVE_GOVERNOR_PER_POLICY \|
		CPUFREQ_NEED_INITIAL_FREQ_CHECK,
		.get = tegra186_cpufreq_get,
		.verify = cpufreq_generic_frequency_table_verify,
		.target_index = tegra186_cpufreq_set_target,
		.init = tegra186_cpufreq_init,

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