From ad80622cbbbb2fdc2e5123d08922f4da89f6a9fc Mon Sep 17 00:00:00 2001
From: Evan Quan <evan.quan@amd.com>
Date: Fri, 20 Aug 2021 16:28:59 +0800
Subject: drm/amd/pm: a quick fix for "divided by zero" error
Git-commit: 8ac1696b1d6b9de0d31447d9e86fe8948b12dec1
Patch-mainline: v5.15-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
Considering Arcturus is a dedicated ASIC for computing, it
will be more proper to drop the support for fan speed reading
and setting. That's on the TODO list.
Signed-off-by: Evan Quan <evan.quan@amd.com>
Reported-by: Rui Teng <rui.teng@amd.com>
Reviewed-by: Guchun Chen <guchun.chen@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Acked-by: Patrik Jakobsson <pjakobsson@suse.de>
---
.../gpu/drm/amd/pm/swsmu/smu11/arcturus_ppt.c | 20 ++++++++++++-------
.../gpu/drm/amd/pm/swsmu/smu11/smu_v11_0.c | 9 +++++++--
2 files changed, 20 insertions(+), 9 deletions(-)
diff --git a/drivers/gpu/drm/amd/pm/swsmu/smu11/arcturus_ppt.c b/drivers/gpu/drm/amd/pm/swsmu/smu11/arcturus_ppt.c
index fbf71fc92b16..273df66cac14 100644
--- a/drivers/gpu/drm/amd/pm/swsmu/smu11/arcturus_ppt.c
+++ b/drivers/gpu/drm/amd/pm/swsmu/smu11/arcturus_ppt.c
@@ -1227,8 +1227,12 @@ static int arcturus_get_fan_speed_rpm(struct smu_context *smu,
tmp64 = (uint64_t)crystal_clock_freq * 60 * 10000;
tach_status = RREG32_SOC15(THM, 0, mmCG_TACH_STATUS_ARCT);
- do_div(tmp64, tach_status);
- *speed = (uint32_t)tmp64;
+ if (tach_status) {
+ do_div(tmp64, tach_status);
+ *speed = (uint32_t)tmp64;
+ } else {
+ *speed = 0;
+ }
break;
}
@@ -1303,12 +1307,14 @@ static int arcturus_get_fan_speed_pwm(struct smu_context *smu,
CG_FDO_CTRL1, FMAX_DUTY100);
duty = REG_GET_FIELD(RREG32_SOC15(THM, 0, mmCG_THERMAL_STATUS_ARCT),
CG_THERMAL_STATUS, FDO_PWM_DUTY);
- if (!duty100)
- return -EINVAL;
- tmp64 = (uint64_t)duty * 255;
- do_div(tmp64, duty100);
- *speed = MIN((uint32_t)tmp64, 255);
+ if (duty100) {
+ tmp64 = (uint64_t)duty * 255;
+ do_div(tmp64, duty100);
+ *speed = MIN((uint32_t)tmp64, 255);
+ } else {
+ *speed = 0;
+ }
return 0;
}
diff --git a/drivers/gpu/drm/amd/pm/swsmu/smu11/smu_v11_0.c b/drivers/gpu/drm/amd/pm/swsmu/smu11/smu_v11_0.c
index 01b9653c39c7..87b055466a33 100644
--- a/drivers/gpu/drm/amd/pm/swsmu/smu11/smu_v11_0.c
+++ b/drivers/gpu/drm/amd/pm/swsmu/smu11/smu_v11_0.c
@@ -1306,8 +1306,13 @@ int smu_v11_0_get_fan_speed_rpm(struct smu_context *smu,
tmp64 = (uint64_t)crystal_clock_freq * 60 * 10000;
tach_status = RREG32_SOC15(THM, 0, mmCG_TACH_STATUS);
- do_div(tmp64, tach_status);
- *speed = (uint32_t)tmp64;
+ if (tach_status) {
+ do_div(tmp64, tach_status);
+ *speed = (uint32_t)tmp64;
+ } else {
+ dev_warn_once(adev->dev, "Got zero output on CG_TACH_STATUS reading!\n");
+ *speed = 0;
+ }
return 0;
}
--
2.38.1