Industrial processor i3255 supports temperatures -40 deg celcius to 105 deg Celcius. The current implementation of k10temp_read_temp rounds off any negative temperatures to '0'. To fix this, the following changes have been made. A flag 'disp_negative' is added to struct k10temp_data to support AMD i3255 processors. Flag 'disp_negative' is set if 3255 processor is found during k10temp_probe. Flag 'disp_negative' is used to determine whether to round off negative temperatures to '0' in k10temp_read_temp. Signed-off-by: Baskaran Kannan <Baski.Kannan@xxxxxxx> --- V4: Changed probe from model number to model id. V3: https://lore.kernel.org/all/20230619165413.806450-1-Baski.Kannan@xxxxxxx/ drivers/hwmon/k10temp.c | 16 ++++++++++++++-- 1 file changed, 14 insertions(+), 2 deletions(-) diff --git a/drivers/hwmon/k10temp.c b/drivers/hwmon/k10temp.c index 7b177b9fbb09..18c4deae82ba 100644 --- a/drivers/hwmon/k10temp.c +++ b/drivers/hwmon/k10temp.c @@ -77,6 +77,12 @@ static DEFINE_MUTEX(nb_smu_ind_mutex); #define ZEN_CUR_TEMP_RANGE_SEL_MASK BIT(19) #define ZEN_CUR_TEMP_TJ_SEL_MASK GENMASK(17, 16) +/* AMD's Industrial processor 3255 supports temperature from -40 deg to 105 deg Celsius. + * Use the model name to identify 3255 CPUs and set a flag to display negative temperature. + * Do not round off to zero for negative Tctl or Tdie values if the flag is set + */ +#define AMD_I3255_STR "3255" + struct k10temp_data { struct pci_dev *pdev; void (*read_htcreg)(struct pci_dev *pdev, u32 *regval); @@ -86,6 +92,7 @@ struct k10temp_data { u32 show_temp; bool is_zen; u32 ccd_offset; + bool disp_negative; }; #define TCTL_BIT 0 @@ -204,12 +211,12 @@ 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) + if (*val < 0 && !data->disp_negative) *val = 0; break; case 1: /* Tdie */ *val = get_raw_temp(data) - data->temp_offset; - if (*val < 0) + if (*val < 0 && !data->disp_negative) *val = 0; break; case 2 ... 13: /* Tccd{1-12} */ @@ -405,6 +412,11 @@ static int k10temp_probe(struct pci_dev *pdev, const struct pci_device_id *id) data->pdev = pdev; data->show_temp |= BIT(TCTL_BIT); /* Always show Tctl */ + if (boot_cpu_data.x86 == 0x17 && + strstr(boot_cpu_data.x86_model_id, AMD_I3255_STR)) { + data->disp_negative = true; + } + if (boot_cpu_data.x86 == 0x15 && ((boot_cpu_data.x86_model & 0xf0) == 0x60 || (boot_cpu_data.x86_model & 0xf0) == 0x70)) { -- 2.25.1
