[AMD Official Use Only - General]
The patch you have mentioned, aef17ca12719, sounds like a work-around for a problem found in some Ryzen Threadripper processors.
If I understand correctly, this work-around (aef17ca12719) has been provided as a blanket fix for all the processors.
The Industrial Processor in question is the Epyc3k i3255.
AMD Family 17h (boot_cpu_data.x86)
AMD model 00h - 0fh (boot_cpu_data.x86_model)
Model Name - contains string "3255"
It supports temperature ranging from -40 degree Celsius to 105 deg Celsius.
We have customers' machines running at -20 deg Celsius. They require that the correct temperature be passed to their tools.
-----Original Message-----
From: Guenter Roeck <groeck7@xxxxxxxxx> On Behalf Of Guenter Roeck
Sent: Thursday, June 8, 2023 8:52 AM
To: Kannan, Baski <Baski.Kannan@xxxxxxx>
Cc: Moger, Babu <Babu.Moger@xxxxxxx>; clemens@xxxxxxxxxx; jdelvare@xxxxxxxx; linux-hwmon@xxxxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx
Subject: Re: [PATCH] hwmon: (k10temp) Report negative temperatures
Caution: This message originated from an External Source. Use proper caution when opening attachments, clicking links, or responding.
On Tue, May 23, 2023 at 02:46:46PM -0700, Guenter Roeck wrote:
On Tue, May 23, 2023 at 03:49:32PM -0500, Baskaran Kannan wrote:
Currently, the tctl and die temperatures are rounded off to zero if
they are less than 0. There are industrial processors which work
below zero.
This was introduced with commit aef17ca12719 ("hwmon: (k10temp) Only
apply temperature offset if result is positive"). This patch would
effecively revert that change. Given the reason for introducing it I
am not convinced that it is a good idea to unconditionally revert it.
Any comments ? I am not inclined to accept this patch as-is. What are the industrial processors ? Is there a means to detect them ?
Guenter
Guenter
To display the correct temperature remove the rounding off.
Signed-off-by: Baskaran Kannan <Baski.Kannan@xxxxxxx>
---
drivers/hwmon/k10temp.c | 4 ----
1 file changed, 4 deletions(-)
diff --git a/drivers/hwmon/k10temp.c b/drivers/hwmon/k10temp.c index
7b177b9fbb09..489ad0b1bc74 100644
--- a/drivers/hwmon/k10temp.c
+++ b/drivers/hwmon/k10temp.c
@@ -204,13 +204,9 @@ static int k10temp_read_temp(struct device *dev, u32 attr, int channel,
switch (channel) {
case 0: /* Tctl */
*val = get_raw_temp(data);
- if (*val < 0)
- *val = 0;
break;
case 1: /* Tdie */
*val = get_raw_temp(data) - data->temp_offset;
- if (*val < 0)
- *val = 0;
break;
case 2 ... 13: /* Tccd{1-12} */
amd_smn_read(amd_pci_dev_to_node_id(data->pdev),
--
2.25.1