From bbd5bb6f8ff1d5948d624a01625dd599369f3c02 Mon Sep 17 00:00:00 2001
From: Harigovindan P <harigovi@codeaurora.org>
Date: Thu, 6 Feb 2020 14:42:01 +0530
Subject: drm/msm/dsi/pll: call vco set rate explicitly
Git-commit: c6659785dfb3f8d75f1fe637e4222ff8178f5280
Patch-mainline: v5.6-rc3
References: jsc#SLE-12680, jsc#SLE-12880, jsc#SLE-12882, jsc#SLE-12883, jsc#SLE-13496, jsc#SLE-15322
For a given byte clock, if VCO recalc value is exactly same as
vco set rate value, vco_set_rate does not get called assuming
VCO is already set to required value. But Due to GDSC toggle,
VCO values are erased in the HW. To make sure VCO is programmed
correctly, we forcefully call set_rate from vco_prepare.
Signed-off-by: Harigovindan P <harigovi@codeaurora.org>
Reviewed-by: Jeffrey Hugo <jeffrey.l.hugo@gmail.com>
Signed-off-by: Rob Clark <robdclark@chromium.org>
Signed-off-by: Patrik Jakobsson <pjakobsson@suse.de>
---
drivers/gpu/drm/msm/dsi/pll/dsi_pll_10nm.c | 6 ++++++
1 file changed, 6 insertions(+)
diff --git a/drivers/gpu/drm/msm/dsi/pll/dsi_pll_10nm.c b/drivers/gpu/drm/msm/dsi/pll/dsi_pll_10nm.c
index 1c894548dd72..6ac04fc303f5 100644
--- a/drivers/gpu/drm/msm/dsi/pll/dsi_pll_10nm.c
+++ b/drivers/gpu/drm/msm/dsi/pll/dsi_pll_10nm.c
@@ -411,6 +411,12 @@ static int dsi_pll_10nm_vco_prepare(struct clk_hw *hw)
if (pll_10nm->slave)
dsi_pll_enable_pll_bias(pll_10nm->slave);
+ rc = dsi_pll_10nm_vco_set_rate(hw,pll_10nm->vco_current_rate, 0);
+ if (rc) {
+ pr_err("vco_set_rate failed, rc=%d\n", rc);
+ return rc;
+ }
+
/* Start PLL */
pll_write(pll_10nm->phy_cmn_mmio + REG_DSI_10nm_PHY_CMN_PLL_CNTRL,
0x01);
--
2.28.0