[PATCH v2] drm/amd/pm: Disable fan control if not supported

[Kasiviswanathan, Harish]

[AMD Official Use Only]

Few comments inline.

-----Original Message-----
From: amd-gfx <amd-gfx-bounces at lists.freedesktop.org> On Behalf Of Elena Sakhnovitch
Sent: Thursday, March 17, 2022 12:45 PM
To: amd-gfx at lists.freedesktop.org
Cc: Sakhnovitch, Elena (Elen) <Elena.Sakhnovitch at amd.com>
Subject: [PATCH v2] drm/amd/pm: Disable fan control if not supported

On Sienna Cichild, not all platforms use PMFW based fan control. On such
ASICs fan control by PMFW will be disabled in PPTable. Disable hwmon
knobs for fan control also as it is not possible to report or control
fan speed on such platforms through driver.
v2: FEATURE_FAN_CONTROL_MASK is replaced with FEATURE_FAN_CONTROL_BIT

Signed-off-by: Elena Sakhnovitch  <elena.sakhnovitch at amd.com>
---
 .../drm/amd/pm/swsmu/smu11/sienna_cichlid_ppt.c   | 15 ++++++++++++++-
 1 file changed, 14 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/amd/pm/swsmu/smu11/sienna_cichlid_ppt.c b/drivers/gpu/drm/amd/pm/swsmu/smu11/sienna_cichlid_ppt.c
index 38f04836c82f..c4fd70376481 100644
--- a/drivers/gpu/drm/amd/pm/swsmu/smu11/sienna_cichlid_ppt.c
+++ b/drivers/gpu/drm/amd/pm/swsmu/smu11/sienna_cichlid_ppt.c
@@ -371,6 +371,18 @@ static void sienna_cichlid_check_bxco_support(struct smu_context *smu)
 	}
 }
 
+static void sienna_cichlid_check_fan_support(struct smu_context *smu)
+{
+	struct smu_table_context *table_context = &smu->smu_table;
+	PPTable_t *pptable = table_context->driver_pptable;
+	/* No sort of fan control possible if PPTable has it disabled */
+	smu->adev->pm.no_fan =
+		!(pptable->FeaturesToRun[0] & ( 1U << FEATURE_FAN_CONTROL_BIT));

[HK]: FEATURE_FAN_CONTROL_BIT (for sienna_cichlid) == 32. This means you would have to use FeaturesToRun[1]. 
[HK]: ( 1U << FEATURE_FAN_CONTROL_BIT)); There is an extra space which checkcommit will complain.

ERROR: space prohibited after that open parenthesis '('
#29: FILE: drivers/gpu/drm/amd/pm/swsmu/smu11/sienna_cichlid_ppt.c:380:
+               !(pptable->FeaturesToRun[0] & ( 1U << FEATURE_FAN_CONTROL_BIT));


+	if (smu->adev->pm.no_fan)
+		dev_info_once(smu->adev->dev,
+			      "PMFW based fan control disabled");
+}
+
 static int sienna_cichlid_check_powerplay_table(struct smu_context *smu)
 {
 	struct smu_table_context *table_context = &smu->smu_table;
@@ -381,6 +393,7 @@ static int sienna_cichlid_check_powerplay_table(struct smu_context *smu)
 		smu->dc_controlled_by_gpio = true;
 
 	sienna_cichlid_check_bxco_support(smu);
+	sienna_cichlid_check_fan_support(smu);
 
 	table_context->thermal_controller_type =
 		powerplay_table->thermal_controller_type;
@@ -410,7 +423,7 @@ static int sienna_cichlid_append_powerplay_table(struct smu_context *smu)
 	GET_PPTABLE_MEMBER(I2cControllers, &table_member);
 	memcpy(table_member, smc_dpm_table->I2cControllers,
 			sizeof(*smc_dpm_table) - sizeof(smc_dpm_table->table_header));
-	
+

[HK]: unnecessary change

 	return 0;
 }
 
-- 
2.25.1