This patch gets minor improvement on glmark2 (160->162).

Seems there's no way for user to change this value, do we? Or there's work pending to expose it to sysfs?

Regards, Qiang

On Thu, Jan 28, 2021 at 3:40 AM Christian Hewitt christianshewitt@gmail.com wrote:

This patch adapts the panfrost pre-defined thresholds change [0] to the lima driver to improve real-world performance. The upthreshold value has been set to ramp GPU frequency to max freq faster (compared to panfrost) to compensate for the lower overall performance of utgard devices.

[0] https://patchwork.kernel.org/project/dri-devel/patch/20210121170445.19761-1-...

Signed-off-by: Christian Hewitt christianshewitt@gmail.com

Change since v1: increased upthreshold from 20 to 30, with a soft dependency on Lukasz delayed timer patch [0]

[0] https://lore.kernel.org/lkml/20210127105121.20345-1-lukasz.luba@arm.com/

drivers/gpu/drm/lima/lima_devfreq.c | 10 +++++++++- drivers/gpu/drm/lima/lima_devfreq.h | 2 ++ 2 files changed, 11 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/lima/lima_devfreq.c b/drivers/gpu/drm/lima/lima_devfreq.c index 5686ad4aaf7c..c9854315a0b5 100644 --- a/drivers/gpu/drm/lima/lima_devfreq.c +++ b/drivers/gpu/drm/lima/lima_devfreq.c @@ -163,8 +163,16 @@ int lima_devfreq_init(struct lima_device *ldev) lima_devfreq_profile.initial_freq = cur_freq; dev_pm_opp_put(opp);

•   /*
  

•    * Setup default thresholds for the simple_ondemand governor.
  

•    * The values are chosen based on experiments.
  

•    */
  

•   ldevfreq->gov_data.upthreshold = 30;
  

•   ldevfreq->gov_data.downdifferential = 5;
  

•   devfreq = devm_devfreq_add_device(dev, &lima_devfreq_profile,
  

•                                     DEVFREQ_GOV_SIMPLE_ONDEMAND, NULL);
  

•                                     DEVFREQ_GOV_SIMPLE_ONDEMAND,
  

•                                     &ldevfreq->gov_data);
    if (IS_ERR(devfreq)) {
            dev_err(dev, "Couldn't initialize GPU devfreq\n");
            ret = PTR_ERR(devfreq);
  

diff --git a/drivers/gpu/drm/lima/lima_devfreq.h b/drivers/gpu/drm/lima/lima_devfreq.h index 2d9b3008ce77..b0c7c736e81a 100644 --- a/drivers/gpu/drm/lima/lima_devfreq.h +++ b/drivers/gpu/drm/lima/lima_devfreq.h @@ -4,6 +4,7 @@ #ifndef __LIMA_DEVFREQ_H__ #define __LIMA_DEVFREQ_H__

+#include <linux/devfreq.h> #include <linux/spinlock.h> #include <linux/ktime.h>

@@ -18,6 +19,7 @@ struct lima_devfreq { struct opp_table *clkname_opp_table; struct opp_table *regulators_opp_table; struct thermal_cooling_device *cooling;

•   struct devfreq_simple_ondemand_data gov_data;
  
    ktime_t busy_time;
    ktime_t idle_time;
  

-- 2.17.1