From b871d988863abb563843ac128f61cd863eec22b7 Mon Sep 17 00:00:00 2001
From: Marijn Suijten <marijn.suijten@somainline.org>
Date: Mon, 11 Oct 2021 22:16:40 +0200
Subject: drm/msm/dsi: Use division result from div_u64_rem in 7nm and 14nm PLL
Git-commit: a377da4b0e9ae248f99932dc74ec356dd4c5db15
Patch-mainline: v5.16-rc1
References: jsc#PED-1166 jsc#PED-1168 jsc#PED-1170 jsc#PED-1218 jsc#PED-1220 jsc#PED-1222 jsc#PED-1223 jsc#PED-1225
div_u64_rem provides the result of the division and additionally the
remainder; don't use this function to solely calculate the remainder
while calculating the division again with div_u64.
A similar improvement was applied earlier to the 10nm pll in
5c191fef4ce2 ("drm/msm/dsi_pll_10nm: Fix dividing the same numbers
twice").
Signed-off-by: Marijn Suijten <marijn.suijten@somainline.org>
Reviewed-By: AngeloGioacchino Del Regno <angelogioacchino.delregno@somainline.org>
Reviewed-by: Abhinav Kumar <abhinavk@codeaurora.org>
Reviewed-by: Stephen Boyd <swboyd@chromium.org>
Link: https://lore.kernel.org/r/20211011201642.167700-1-marijn.suijten@somainline.org
Signed-off-by: Rob Clark <robdclark@chromium.org>
Acked-by: Patrik Jakobsson <pjakobsson@suse.de>
---
drivers/gpu/drm/msm/dsi/phy/dsi_phy_14nm.c | 4 +---
drivers/gpu/drm/msm/dsi/phy/dsi_phy_7nm.c | 4 +---
2 files changed, 2 insertions(+), 6 deletions(-)
diff --git a/drivers/gpu/drm/msm/dsi/phy/dsi_phy_14nm.c b/drivers/gpu/drm/msm/dsi/phy/dsi_phy_14nm.c
index 5b4e991f220d..c62d90361bd2 100644
--- a/drivers/gpu/drm/msm/dsi/phy/dsi_phy_14nm.c
+++ b/drivers/gpu/drm/msm/dsi/phy/dsi_phy_14nm.c
@@ -213,9 +213,7 @@ static void pll_14nm_dec_frac_calc(struct dsi_pll_14nm *pll, struct dsi_pll_conf
DBG("vco_clk_rate=%lld ref_clk_rate=%lld", vco_clk_rate, fref);
dec_start_multiple = div_u64(vco_clk_rate * multiplier, fref);
- div_u64_rem(dec_start_multiple, multiplier, &div_frac_start);
-
- dec_start = div_u64(dec_start_multiple, multiplier);
+ dec_start = div_u64_rem(dec_start_multiple, multiplier, &div_frac_start);
pconf->dec_start = (u32)dec_start;
pconf->div_frac_start = div_frac_start;
diff --git a/drivers/gpu/drm/msm/dsi/phy/dsi_phy_7nm.c b/drivers/gpu/drm/msm/dsi/phy/dsi_phy_7nm.c
index cb297b08458e..079613d2aaa9 100644
--- a/drivers/gpu/drm/msm/dsi/phy/dsi_phy_7nm.c
+++ b/drivers/gpu/drm/msm/dsi/phy/dsi_phy_7nm.c
@@ -114,9 +114,7 @@ static void dsi_pll_calc_dec_frac(struct dsi_pll_7nm *pll, struct dsi_pll_config
multiplier = 1 << FRAC_BITS;
dec_multiple = div_u64(pll_freq * multiplier, divider);
- div_u64_rem(dec_multiple, multiplier, &frac);
-
- dec = div_u64(dec_multiple, multiplier);
+ dec = div_u64_rem(dec_multiple, multiplier, &frac);
if (!(pll->phy->cfg->quirks & DSI_PHY_7NM_QUIRK_V4_1))
config->pll_clock_inverters = 0x28;
--
2.38.1