qcom-cpufreq: skip frequencies that round to same rate

Since not all frequencies line up between speed bins,
the common cpufreq table sometimes has frequencies
that round up the same actual frequency.

Fix this by skipping those frequencies.

Change-Id: I0516cc67a1343150f3d1f838b9d9b329e8e1e498
Signed-off-by: Rohit Gupta <rohgup@codeaurora.org>
Signed-off-by: David Keitel <dkeitel@codeaurora.org>

1 files changed, 12 insertions, 20 deletions

diff --git a/drivers/cpufreq/qcom-cpufreq.c b/drivers/cpufreq/qcom-cpufreq.c
index 82861b1dbe46..2aa7b783f276 100644
--- a/drivers/cpufreq/qcom-cpufreq.c
+++ b/drivers/cpufreq/qcom-cpufreq.c
@@ -3,7 +3,7 @@
  * MSM architecture cpufreq driver
  *
  * Copyright (C) 2007 Google, Inc.
- * Copyright (c) 2007-2015, The Linux Foundation. All rights reserved.
+ * Copyright (c) 2007-2016, The Linux Foundation. All rights reserved.
  * Author: Mike A. Chan <mikechan@google.com>
  *
  * This software is licensed under the terms of the GNU General Public
@@ -320,7 +320,7 @@ static struct cpufreq_driver msm_cpufreq_driver = {
 static struct cpufreq_frequency_table *cpufreq_parse_dt(struct device *dev,
 						char *tbl_name, int cpu)
 {
-	int ret, nf, i;
+	int ret, nf, i, j;
 	u32 *data;
 	struct cpufreq_frequency_table *ftbl;
 
@@ -344,6 +344,7 @@ static struct cpufreq_frequency_table *cpufreq_parse_dt(struct device *dev,
 	if (!ftbl)
 		return ERR_PTR(-ENOMEM);
 
+	j = 0;
 	for (i = 0; i < nf; i++) {
 		unsigned long f;
 
@@ -353,29 +354,20 @@ static struct cpufreq_frequency_table *cpufreq_parse_dt(struct device *dev,
 		f /= 1000;
 
 		/*
-		 * Check if this is the last feasible frequency in the table.
+		 * Don't repeat frequencies if they round up to the same clock
+		 * frequency.
 		 *
-		 * The table listing frequencies higher than what the HW can
-		 * support is not an error since the table might be shared
-		 * across CPUs in different speed bins. It's also not
-		 * sufficient to check if the rounded rate is lower than the
-		 * requested rate as it doesn't cover the following example:
-		 *
-		 * Table lists: 2.2 GHz and 2.5 GHz.
-		 * Rounded rate returns: 2.2 GHz and 2.3 GHz.
-		 *
-		 * In this case, we can CPUfreq to use 2.2 GHz and 2.3 GHz
-		 * instead of rejecting the 2.5 GHz table entry.
 		 */
-		if (i > 0 && f <= ftbl[i-1].frequency)
-			break;
+		if (j > 0 && f <= ftbl[j - 1].frequency)
+			continue;
 
-		ftbl[i].driver_data = i;
-		ftbl[i].frequency = f;
+		ftbl[j].driver_data = j;
+		ftbl[j].frequency = f;
+		j++;
 	}
 
-	ftbl[i].driver_data = i;
-	ftbl[i].frequency = CPUFREQ_TABLE_END;
+	ftbl[j].driver_data = j;
+	ftbl[j].frequency = CPUFREQ_TABLE_END;
 
 	devm_kfree(dev, data);