From: Jon Hunter <jonathanh@nvidia.com>
Date: Wed, 2 Dec 2020 09:14:18 +0000 (+0000)
Subject: cpufreq: tegra194: Remove unnecessary frequency calculation
X-Git-Tag: accepted/tizen/unified/20230118.172025~8185^2^2~9^2~2
X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=93549516d44681261d2d209186449c6125beccc1;p=platform%2Fkernel%2Flinux-rpi.git

cpufreq: tegra194: Remove unnecessary frequency calculation

The Tegra194 CPUFREQ driver sets the CPUFREQ_NEED_INITIAL_FREQ_CHECK
flag which means that the CPUFREQ framework will call the 'get' callback
on boot to determine the current frequency of the CPUs. Therefore, it is
not necessary for the Tegra194 CPUFREQ driver to internally call the
tegra194_get_speed_common() during initialisation to query the current
frequency as well. Fix this by removing the call to the
tegra194_get_speed_common() during initialisation and simplify the code.

Signed-off-by: Jon Hunter <jonathanh@nvidia.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
---

diff --git a/drivers/cpufreq/tegra194-cpufreq.c b/drivers/cpufreq/tegra194-cpufreq.c
index 7901587..a706ba9 100644
--- a/drivers/cpufreq/tegra194-cpufreq.c
+++ b/drivers/cpufreq/tegra194-cpufreq.c
@@ -21,7 +21,6 @@
 #define KHZ                     1000
 #define REF_CLK_MHZ             408 /* 408 MHz */
 #define US_DELAY                500
-#define US_DELAY_MIN            2
 #define CPUFREQ_TBL_STEP_HZ     (50 * KHZ * KHZ)
 #define MAX_CNT                 ~0U
 
@@ -44,7 +43,6 @@ struct tegra194_cpufreq_data {
 
 struct tegra_cpu_ctr {
 	u32 cpu;
-	u32 delay;
 	u32 coreclk_cnt, last_coreclk_cnt;
 	u32 refclk_cnt, last_refclk_cnt;
 };
@@ -112,7 +110,7 @@ static void tegra_read_counters(struct work_struct *work)
 	val = read_freq_feedback();
 	c->last_refclk_cnt = lower_32_bits(val);
 	c->last_coreclk_cnt = upper_32_bits(val);
-	udelay(c->delay);
+	udelay(US_DELAY);
 	val = read_freq_feedback();
 	c->refclk_cnt = lower_32_bits(val);
 	c->coreclk_cnt = upper_32_bits(val);
@@ -139,7 +137,7 @@ static void tegra_read_counters(struct work_struct *work)
  * @cpu - logical cpu whose freq to be updated
  * Returns freq in KHz on success, 0 if cpu is offline
  */
-static unsigned int tegra194_get_speed_common(u32 cpu, u32 delay)
+static unsigned int tegra194_get_speed_common(u32 cpu)
 {
 	struct read_counters_work read_counters_work;
 	struct tegra_cpu_ctr c;
@@ -153,7 +151,6 @@ static unsigned int tegra194_get_speed_common(u32 cpu, u32 delay)
 	 * interrupts enabled.
 	 */
 	read_counters_work.c.cpu = cpu;
-	read_counters_work.c.delay = delay;
 	INIT_WORK_ONSTACK(&read_counters_work.work, tegra_read_counters);
 	queue_work_on(cpu, read_counters_wq, &read_counters_work.work);
 	flush_work(&read_counters_work.work);
@@ -209,7 +206,7 @@ static unsigned int tegra194_get_speed(u32 cpu)
 	smp_call_function_single(cpu, get_cpu_cluster, &cl, true);
 
 	/* reconstruct actual cpu freq using counters */
-	rate = tegra194_get_speed_common(cpu, US_DELAY);
+	rate = tegra194_get_speed_common(cpu);
 
 	/* get last written ndiv value */
 	ret = smp_call_function_single(cpu, get_cpu_ndiv, &ndiv, true);
@@ -248,9 +245,6 @@ static int tegra194_cpufreq_init(struct cpufreq_policy *policy)
 	if (cl >= data->num_clusters)
 		return -EINVAL;
 
-	/* boot freq */
-	policy->cur = tegra194_get_speed_common(policy->cpu, US_DELAY_MIN);
-
 	/* set same policy for all cpus in a cluster */
 	for (cpu = (cl * 2); cpu < ((cl + 1) * 2); cpu++)
 		cpumask_set_cpu(cpu, policy->cpus);