[PATCH v2] drm/amd/pp: enable power limit increase in OD mode

[Deucher, Alexander]

Reviewed-by: Alex Deucher <alexander.deucher at amd.com>

________________________________
From: amd-gfx <amd-gfx-bounces at lists.freedesktop.org> on behalf of Greathouse, Joseph <Joseph.Greathouse at amd.com>
Sent: Thursday, October 18, 2018 3:44:39 PM
To: amd-gfx at lists.freedesktop.org
Cc: Greathouse, Joseph
Subject: [PATCH v2] drm/amd/pp: enable power limit increase in OD mode

OverDrive mode allows users to increase the maximum SCLK and MCLK
frequencies beyond the default on the GPU. However, this may not
results in large performance gains if the GPU then runs into its TDP
power limit. This patch adds the capability to increase the power
limit of a GPU above its default maximum.

This is only allowed when overdrive is enabled in the ppfeaturemask,
since this is an overdrive feature. The TDPODLimit value from the
VBIOS describes how how much higher the TDP should be allowed to go
over its default, in percentage.

v2: Moved dereference of hwmgr to after its validity check

Signed-off-by: Joseph Greathouse <Joseph.Greathouse at amd.com>
---
 drivers/gpu/drm/amd/powerplay/amd_powerplay.c | 16 ++++++++++++++--
 1 file changed, 14 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/amd/powerplay/amd_powerplay.c b/drivers/gpu/drm/amd/powerplay/amd_powerplay.c
index e8964ca..586f1ff 100644
--- a/drivers/gpu/drm/amd/powerplay/amd_powerplay.c
+++ b/drivers/gpu/drm/amd/powerplay/amd_powerplay.c
@@ -963,6 +963,7 @@ static int pp_dpm_switch_power_profile(void *handle,
 static int pp_set_power_limit(void *handle, uint32_t limit)
 {
         struct pp_hwmgr *hwmgr = handle;
+       uint32_t max_power_limit;

         if (!hwmgr || !hwmgr->pm_en)
                 return -EINVAL;
@@ -975,7 +976,13 @@ static int pp_set_power_limit(void *handle, uint32_t limit)
         if (limit == 0)
                 limit = hwmgr->default_power_limit;

-       if (limit > hwmgr->default_power_limit)
+       max_power_limit = hwmgr->default_power_limit;
+       if (hwmgr->od_enabled) {
+               max_power_limit *= (100 + hwmgr->platform_descriptor.TDPODLimit);
+               max_power_limit /= 100;
+       }
+
+       if (limit > max_power_limit)
                 return -EINVAL;

         mutex_lock(&hwmgr->smu_lock);
@@ -994,8 +1001,13 @@ static int pp_get_power_limit(void *handle, uint32_t *limit, bool default_limit)

         mutex_lock(&hwmgr->smu_lock);

-       if (default_limit)
+       if (default_limit) {
                 *limit = hwmgr->default_power_limit;
+               if (hwmgr->od_enabled) {
+                       *limit *= (100 + hwmgr->platform_descriptor.TDPODLimit);
+                       *limit /= 100;
+               }
+       }
         else
                 *limit = hwmgr->power_limit;

--
2.7.4

_______________________________________________
amd-gfx mailing list
amd-gfx at lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/amd-gfx
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <https://lists.freedesktop.org/archives/amd-gfx/attachments/20181018/93dab215/attachment.html>