From 314630017b3ebb04c89f0b1d1acf8392dd092391 Mon Sep 17 00:00:00 2001
From: Guenter Roeck <linux@roeck-us.net>
Date: Thu, 8 Apr 2021 11:27:10 -0700
Subject: hwmon: (amd_energy) Use unified function to read energy data

The driver implements two separate functions to read and update
energy values. One function is called periodically and updates
cached enery information to avoid loss of data, the other reads
energy data on demand to report it to userspace. The second
function reads current energy data, adds the difference to the
data previously obtained by the first function, and then discards
the updated data.

Simplify the code and always call the first function, then report
the energy data obtained by this function to userspace.

Cc: Naveen Krishna Chatradhi <nchatrad@amd.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
---
 drivers/hwmon/amd_energy.c | 31 ++++++-------------------------
 1 file changed, 6 insertions(+), 25 deletions(-)

(limited to 'drivers/hwmon')

diff --git a/drivers/hwmon/amd_energy.c b/drivers/hwmon/amd_energy.c
index a86cc8d6d93d0..93bad64039f1d 100644
--- a/drivers/hwmon/amd_energy.c
+++ b/drivers/hwmon/amd_energy.c
@@ -118,35 +118,12 @@ static void read_accumulate(struct amd_energy_data *data)
 	data->core_id++;
 }
 
-static void amd_add_delta(struct amd_energy_data *data, int ch,
-			  int cpu, long *val, u32 reg)
-{
-	struct sensor_accumulator *accum;
-	u64 input;
-
-	mutex_lock(&data->lock);
-	rdmsrl_safe_on_cpu(cpu, reg, &input);
-	input &= AMD_ENERGY_MASK;
-
-	accum = &data->accums[ch];
-	if (input >= accum->prev_value)
-		input += accum->energy_ctr -
-				accum->prev_value;
-	else
-		input += UINT_MAX - accum->prev_value +
-				accum->energy_ctr;
-
-	/* Energy consumed = (1/(2^ESU) * RAW * 1000000UL) μJoules */
-	*val = div64_ul(input * 1000000UL, BIT(data->energy_units));
-
-	mutex_unlock(&data->lock);
-}
-
 static int amd_energy_read(struct device *dev,
 			   enum hwmon_sensor_types type,
 			   u32 attr, int channel, long *val)
 {
 	struct amd_energy_data *data = dev_get_drvdata(dev);
+	struct sensor_accumulator *accum;
 	u32 reg;
 	int cpu;
 
@@ -162,7 +139,11 @@ static int amd_energy_read(struct device *dev,
 
 		reg = ENERGY_CORE_MSR;
 	}
-	amd_add_delta(data, channel, cpu, val, reg);
+
+	accumulate_delta(data, channel, cpu, reg);
+	accum = &data->accums[channel];
+
+	*val = div64_ul(accum->energy_ctr * 1000000UL, BIT(data->energy_units));
 
 	return 0;
 }
-- 
cgit 1.2.3-1.el7