On 08-03-19, 17:47, Gregory CLEMENT wrote:

The frequency calculation was based on the current(max) frequency of the CPU. However for low frequency, the value used was already the parent frequency divided by a factor of 2.

Instead of using this frequency, this fix directly get the frequency from the parent clock.

Fixes: 92ce45fb875d ("cpufreq: Add DVFS support for Armada 37xx") Cc: stable@vger.kernel.org Reported-by: Christian Neubert christian.neubert.86@gmail.com Signed-off-by: Gregory CLEMENT gregory.clement@bootlin.com

---

drivers/cpufreq/armada-37xx-cpufreq.c | 22 +++++++++++++++++++--- 1 file changed, 19 insertions(+), 3 deletions(-)

diff --git a/drivers/cpufreq/armada-37xx-cpufreq.c b/drivers/cpufreq/armada-37xx-cpufreq.c index ad4463e4266e..a0962463805e 100644 --- a/drivers/cpufreq/armada-37xx-cpufreq.c +++ b/drivers/cpufreq/armada-37xx-cpufreq.c @@ -373,11 +373,11 @@ static int __init armada37xx_cpufreq_driver_init(void) struct armada_37xx_dvfs *dvfs; struct platform_device *pdev; unsigned long freq;

• unsigned int cur_frequency;

• unsigned int cur_frequency, base_frequency; struct regmap *nb_pm_base, *avs_base; struct device *cpu_dev; int load_lvl, ret;

• struct clk *clk;

• struct clk *clk, *parent;

nb_pm_base = syscon_regmap_lookup_by_compatible("marvell,armada-3700-nb-pm"); @@ -413,6 +413,22 @@ static int __init armada37xx_cpufreq_driver_init(void) return PTR_ERR(clk); }

• parent = clk_get_parent(clk);
• if (IS_ERR(parent)) {

• dev_err(cpu_dev, "Cannot get parent clock for CPU0\n");
  

• clk_put(clk);
  

• return PTR_ERR(parent);
  

• }
• /* Get parent CPU frequency */
• base_frequency = clk_get_rate(parent);
• if (!base_frequency) {

• dev_err(cpu_dev, "Failed to get parent clock rate for CPU\n");
  

• clk_put(clk);
  

• return -EINVAL;
  

• }
• /* Get nominal (current) CPU frequency */ cur_frequency = clk_get_rate(clk); if (!cur_frequency) {

@@ -445,7 +461,7 @@ static int __init armada37xx_cpufreq_driver_init(void) for (load_lvl = ARMADA_37XX_DVFS_LOAD_0; load_lvl < LOAD_LEVEL_NR; load_lvl++) { unsigned long u_volt = avs_map[dvfs->avs[load_lvl]] * 1000;

• freq = cur_frequency / dvfs->divider[load_lvl];
  

• freq = base_frequency / dvfs->divider[load_lvl];
  

  ret = dev_pm_opp_add(cpu_dev, freq, u_volt); if (ret) goto remove_opp;

Great. I was wondering on why the top frequency was skipped :)