drm/radeon/dpm: fix calculations in si_calculate_leakage_for_v_and_t_formula

Need to make some slight adjustments for the fixed point math to
work properly.

Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

1 files changed, 5 insertions, 3 deletions

diff --git a/drivers/gpu/drm/radeon/si_dpm.c b/drivers/gpu/drm/radeon/si_dpm.c
index 1604a87cf2fe..cfb444870068 100644
--- a/drivers/gpu/drm/radeon/si_dpm.c
+++ b/drivers/gpu/drm/radeon/si_dpm.c
@@ -1765,8 +1765,9 @@ static void si_calculate_leakage_for_v_and_t_formula(const struct ni_leakage_coe
 {
         s64 kt, kv, leakage_w, i_leakage, vddc;
         s64 temperature, t_slope, t_intercept, av, bv, t_ref;
+        s64 tmp;
 
-        i_leakage = drm_int2fixp(ileakage / 100);
+        i_leakage = drm_int2fixp(ileakage) / 100;
         vddc = div64_s64(drm_int2fixp(v), 1000);
         temperature = div64_s64(drm_int2fixp(t), 1000);
 
@@ -1776,8 +1777,9 @@ static void si_calculate_leakage_for_v_and_t_formula(const struct ni_leakage_coe
         bv = div64_s64(drm_int2fixp(coeff->bv), 100000000);
         t_ref = drm_int2fixp(coeff->t_ref);
 
-        kt = drm_fixp_div(drm_fixp_exp(drm_fixp_mul(drm_fixp_mul(t_slope, vddc) + t_intercept, temperature)),
-                          drm_fixp_exp(drm_fixp_mul(drm_fixp_mul(t_slope, vddc) + t_intercept, t_ref)));
+        tmp = drm_fixp_mul(t_slope, vddc) + t_intercept;
+        kt = drm_fixp_exp(drm_fixp_mul(tmp, temperature));
+        kt = drm_fixp_div(kt, drm_fixp_exp(drm_fixp_mul(tmp, t_ref)));
         kv = drm_fixp_mul(av, drm_fixp_exp(drm_fixp_mul(bv, vddc)));
 
         leakage_w = drm_fixp_mul(drm_fixp_mul(drm_fixp_mul(i_leakage, kt), kv), vddc);