Patch "drm/amd/powerplay/smu7: add vblank check for mclk switching (v2)" has been added to the 4.9-stable tree

[<gregkh@linuxfoundation.org>]

This is a note to let you know that I've just added the patch titled

    drm/amd/powerplay/smu7: add vblank check for mclk switching (v2)

to the 4.9-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     drm-amd-powerplay-smu7-add-vblank-check-for-mclk-switching-v2.patch
and it can be found in the queue-4.9 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@vger.kernel.org> know about it.


>From 09be4a5219610a6fae3215d4f51f948d6f5d2609 Mon Sep 17 00:00:00 2001
From: Alex Deucher <alexander.deucher@amd.com>
Date: Thu, 11 May 2017 13:46:12 -0400
Subject: drm/amd/powerplay/smu7: add vblank check for mclk switching (v2)
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

From: Alex Deucher <alexander.deucher@amd.com>

commit 09be4a5219610a6fae3215d4f51f948d6f5d2609 upstream.

Check to make sure the vblank period is long enough to support
mclk switching.

v2: drop needless initial assignment (Nils)

bug: https://bugs.freedesktop.org/show_bug.cgi?id=96868

Acked-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Rex Zhu <Rex.Zhu@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 drivers/gpu/drm/amd/powerplay/hwmgr/smu7_hwmgr.c |   31 ++++++++++++++++++++---
 1 file changed, 27 insertions(+), 4 deletions(-)

--- a/drivers/gpu/drm/amd/powerplay/hwmgr/smu7_hwmgr.c
+++ b/drivers/gpu/drm/amd/powerplay/hwmgr/smu7_hwmgr.c
@@ -2495,6 +2495,28 @@ static int smu7_get_power_state_size(str
 	return sizeof(struct smu7_power_state);
 }
 
+static int smu7_vblank_too_short(struct pp_hwmgr *hwmgr,
+				 uint32_t vblank_time_us)
+{
+	struct smu7_hwmgr *data = (struct smu7_hwmgr *)(hwmgr->backend);
+	uint32_t switch_limit_us;
+
+	switch (hwmgr->chip_id) {
+	case CHIP_POLARIS10:
+	case CHIP_POLARIS11:
+	case CHIP_POLARIS12:
+		switch_limit_us = data->is_memory_gddr5 ? 190 : 150;
+		break;
+	default:
+		switch_limit_us = data->is_memory_gddr5 ? 450 : 150;
+		break;
+	}
+
+	if (vblank_time_us < switch_limit_us)
+		return true;
+	else
+		return false;
+}
 
 static int smu7_apply_state_adjust_rules(struct pp_hwmgr *hwmgr,
 				struct pp_power_state *request_ps,
@@ -2509,6 +2531,7 @@ static int smu7_apply_state_adjust_rules
 	bool disable_mclk_switching;
 	bool disable_mclk_switching_for_frame_lock;
 	struct cgs_display_info info = {0};
+	struct cgs_mode_info mode_info = {0};
 	const struct phm_clock_and_voltage_limits *max_limits;
 	uint32_t i;
 	struct smu7_hwmgr *data = (struct smu7_hwmgr *)(hwmgr->backend);
@@ -2517,6 +2540,7 @@ static int smu7_apply_state_adjust_rules
 	int32_t count;
 	int32_t stable_pstate_sclk = 0, stable_pstate_mclk = 0;
 
+	info.mode_info = &mode_info;
 	data->battery_state = (PP_StateUILabel_Battery ==
 			request_ps->classification.ui_label);
 
@@ -2543,8 +2567,6 @@ static int smu7_apply_state_adjust_rules
 
 	cgs_get_active_displays_info(hwmgr->device, &info);
 
-	/*TO DO result = PHM_CheckVBlankTime(hwmgr, &vblankTooShort);*/
-
 	minimum_clocks.engineClock = hwmgr->display_config.min_core_set_clock;
 	minimum_clocks.memoryClock = hwmgr->display_config.min_mem_set_clock;
 
@@ -2609,8 +2631,9 @@ static int smu7_apply_state_adjust_rules
 				    PHM_PlatformCaps_DisableMclkSwitchingForFrameLock);
 
 
-	disable_mclk_switching = (1 < info.display_count) ||
-				    disable_mclk_switching_for_frame_lock;
+	disable_mclk_switching = ((1 < info.display_count) ||
+				  disable_mclk_switching_for_frame_lock ||
+				  smu7_vblank_too_short(hwmgr, mode_info.vblank_time_us));
 
 	sclk = smu7_ps->performance_levels[0].engine_clock;
 	mclk = smu7_ps->performance_levels[0].memory_clock;


Patches currently in stable-queue which might be from alexander.deucher@amd.com are

queue-4.9/drm-amd-powerplay-smu7-add-vblank-check-for-mclk-switching-v2.patch
queue-4.9/drm-radeon-fix-vram_size-visible-values-in-drm_radeon_gem_info-ioctl.patch
queue-4.9/drm-radeon-ci-disable-mclk-switching-for-high-refresh-rates-v2.patch
queue-4.9/drm-radeon-unbreak-hpd-handling-for-r600.patch
queue-4.9/drm-amd-powerplay-smu7-disable-mclk-switching-for-high-refresh-rates.patch