ux500: cpufreq: try to fix merge regressions

Signed-off-by: Philippe Langlais <philippe.langlais@linaro.org>

1 files changed, 62 insertions, 8 deletions

diff --git a/drivers/cpufreq/db8500-cpufreq.c b/drivers/cpufreq/db8500-cpufreq.c
index d90456a809f..298962fd5ee 100644
--- a/drivers/cpufreq/db8500-cpufreq.c
+++ b/drivers/cpufreq/db8500-cpufreq.c
@@ -18,29 +18,72 @@
 static struct cpufreq_frequency_table freq_table[] = {
 	[0] = {
 		.index = 0,
-		.frequency = 300000,
+		.frequency = 200000,
 	},
 	[1] = {
 		.index = 1,
-		.frequency = 600000,
+		.frequency = 300000,
 	},
 	[2] = {
-		/* Used for MAX_OPP, if available */
 		.index = 2,
-		.frequency = CPUFREQ_TABLE_END,
+		.frequency = 600000,
 	},
 	[3] = {
+		/* Used for MAX_OPP, if available */
 		.index = 3,
 		.frequency = CPUFREQ_TABLE_END,
 	},
+	[4] = {
+		.index = 4,
+		.frequency = CPUFREQ_TABLE_END,
+	},
 };
 
 static enum arm_opp idx2opp[] = {
+	ARM_EXTCLK,
 	ARM_50_OPP,
 	ARM_100_OPP,
 	ARM_MAX_OPP
 };
 
+/*
+ * Below is a temporary workaround for wlan performance issues
+ */
+
+#include <linux/kernel_stat.h>
+#include <linux/workqueue.h>
+#include <linux/cpu.h>
+
+#include <mach/irqs.h>
+
+#define WLAN_PROBE_DELAY 3000 /* 3 seconds */
+#define WLAN_LIMIT (3000/3) /* If we have more than 1000 irqs per second */
+
+static struct delayed_work work_wlan_workaround;
+bool wlan_mode_on;
+
+static void wlan_load(struct work_struct *work)
+{
+	int cpu;
+	unsigned int num_irqs = 0;
+	static unsigned int old_num_irqs = UINT_MAX;
+
+	for_each_online_cpu(cpu)
+		num_irqs += kstat_irqs_cpu(IRQ_DB8500_SDMMC1, cpu);
+
+	if ((num_irqs > old_num_irqs) &&
+	    (num_irqs - old_num_irqs) > WLAN_LIMIT)
+		wlan_mode_on = true;
+	else
+		wlan_mode_on = false;
+
+	old_num_irqs = num_irqs;
+
+	schedule_delayed_work_on(0,
+				 &work_wlan_workaround,
+				 msecs_to_jiffies(WLAN_PROBE_DELAY));
+}
+
 static struct freq_attr *db8500_cpufreq_attr[] = {
 	&cpufreq_freq_attr_scaling_available_freqs,
 	NULL,
@@ -64,6 +107,10 @@ static int db8500_cpufreq_target(struct cpufreq_policy *policy,
 	if (target_freq > policy->cpuinfo.max_freq)
 		target_freq = policy->cpuinfo.max_freq;
 
+	/* A work around for wlan performance issues */
+	if (wlan_mode_on)
+		target_freq = policy->cpuinfo.max_freq;
+
 	/* Lookup the next frequency */
 	if (cpufreq_frequency_table_target
 	    (policy, freq_table, target_freq, relation, &idx)) {
@@ -108,13 +155,20 @@ static int __cpuinit db8500_cpufreq_init(struct cpufreq_policy *policy)
 
 	BUILD_BUG_ON(ARRAY_SIZE(idx2opp) + 1 != ARRAY_SIZE(freq_table));
 
-	if (cpu_is_u8500v2() && !prcmu_is_u8400()) {
-		freq_table[0].frequency = 400000;
-		freq_table[1].frequency = 800000;
+	if (!prcmu_is_u8400()) {
+		freq_table[1].frequency = 400000;
+		freq_table[2].frequency = 800000;
 		if (prcmu_has_arm_maxopp())
-			freq_table[2].frequency = 1000000;
+			freq_table[3].frequency = 1000000;
 	}
 
+	INIT_DELAYED_WORK_DEFERRABLE(&work_wlan_workaround,
+				     wlan_load);
+
+	schedule_delayed_work_on(0,
+				 &work_wlan_workaround,
+				 msecs_to_jiffies(WLAN_PROBE_DELAY));
+
 	/* get policy fields based on the table */
 	res = cpufreq_frequency_table_cpuinfo(policy, freq_table);
 	if (!res)