[PATCH v4] hwmon: (nct6775) add support for TSI temperature registers

Zev Weiss
2022-01-13T16:46:49Z

These registers report CPU temperatures (and, depending on the system,
sometimes chipset temperatures) via the TSI interface on AMD systems.
They're distinct from most of the other Super-IO temperature readings
(CPUTIN, SYSTIN, etc.) in that they're not a selectable source for
monitoring and are in a different (higher resolution) format, but can
still provide useful temperature data.

Signed-off-by: Zev Weiss <zev@bewilderbeest.net>
Tested-by: Renze Nicolai <renze@rnplus.nl>
---

This patch has been tested on NCT6779 and NCT6798[0] hardware on
(respectively) ASRock Rack ROMED8HM3 and X570D4U boards, and seems to
work as expected; the implementation for the other chips supported by
the driver is purely based on the datasheets and has not been tested
(for lack of available hardware).

[0] Or at least, its chip ID registers identify it as an NCT6798 and
it seems to behave consistently with that, though it's actually
physically labeled as an NCT6796.

Changes since v3 [1]:
- removed "unknown number of TSI temp registers" warning

Changes since v2 [2]:
- fixed a pair of <= that should have been < in is_word_sized()
- fixed nct6116 switch case mistakenly referencing NCT6106_REG_TSI_TEMP

Changes since v1 [3]:
- simplified logic in is_word_sized()

[1] https://lore.kernel.org/linux-hwmon/20220112034824.3467-1-zev@bewilderbeest.net/
[2] https://lore.kernel.org/linux-hwmon/20211226051438.5081-1-zev@bewilderbeest.net/
[3] https://lore.kernel.org/linux-hwmon/Yb7RVu6fQc+tLIAg@hatter.bewilderbeest.net/

drivers/hwmon/nct6775.c | 129 ++++++++++++++++++++++++++++++++++++++--
1 file changed, 123 insertions(+), 6 deletions(-)

diff --git a/drivers/hwmon/nct6775.c b/drivers/hwmon/nct6775.c
index fd3f91cb01c6..6c1ad82ad54b 100644
--- a/drivers/hwmon/nct6775.c
+++ b/drivers/hwmon/nct6775.c
@@ -308,6 +308,7 @@ static void superio_exit(struct nct6775_sio_data *sio_data)

#define NUM_TEMP 10 /* Max number of temp attribute sets w/ limits*/
#define NUM_TEMP_FIXED 6 /* Max number of fixed temp attribute sets */
+#define NUM_TSI_TEMP 8 /* Max number of TSI temp register pairs */

#define NUM_REG_ALARM 7 /* Max number of alarm registers */
#define NUM_REG_BEEP 5 /* Max number of beep registers */
@@ -498,6 +499,8 @@ static const u16 NCT6775_REG_TEMP_CRIT[32] = {
[11] = 0xa07
};

+static const u16 NCT6775_REG_TSI_TEMP[] = { 0x669 };
+
/* NCT6776 specific data */

/* STEP_UP_TIME and STEP_DOWN_TIME regs are swapped for all chips but NCT6775 */
@@ -581,6 +584,9 @@ static const u16 NCT6776_REG_TEMP_CRIT[32] = {
[12] = 0x70a,
};

+static const u16 NCT6776_REG_TSI_TEMP[] = {
+ 0x409, 0x40b, 0x40d, 0x40f, 0x411, 0x413, 0x415, 0x417 };
+
/* NCT6779 specific data */

static const u16 NCT6779_REG_IN[] = {
@@ -864,6 +870,8 @@ static const char *const nct6796_temp_label[] = {
#define NCT6796_TEMP_MASK 0xbfff0ffe
#define NCT6796_VIRT_TEMP_MASK 0x80000c00

+static const u16 NCT6796_REG_TSI_TEMP[] = { 0x409, 0x40b };
+
static const char *const nct6798_temp_label[] = {
"",
"SYSTIN",
@@ -1005,6 +1013,8 @@ static const u16 NCT6106_REG_TEMP_CRIT[32] = {
[12] = 0x205,
};

+static const u16 NCT6106_REG_TSI_TEMP[] = { 0x59, 0x5b, 0x5d, 0x5f, 0x61, 0x63, 0x65, 0x67 };
+
/* NCT6112D/NCT6114D/NCT6116D specific data */

static const u16 NCT6116_REG_FAN[] = { 0x20, 0x22, 0x24, 0x26, 0x28 };
@@ -1069,6 +1079,8 @@ static const s8 NCT6116_BEEP_BITS[] = {
34, -1 /* intrusion0, intrusion1 */
};

+static const u16 NCT6116_REG_TSI_TEMP[] = { 0x59, 0x5b };
+
static enum pwm_enable reg_to_pwm_enable(int pwm, int mode)
{
if (mode == 0 && pwm == 255)
@@ -1169,6 +1181,12 @@ static inline u8 in_to_reg(u32 val, u8 nr)
return clamp_val(DIV_ROUND_CLOSEST(val * 100, scale_in[nr]), 0, 255);
}

+/* TSI temperatures are in 8.3 format */
+static inline unsigned int tsi_temp_from_reg(unsigned int reg)
+{
+ return (reg >> 5) * 125;
+}
+
/*
* Data structures and manipulation thereof
*/
@@ -1179,7 +1197,7 @@ struct nct6775_data {
enum kinds kind;
const char *name;

- const struct attribute_group *groups[6];
+ const struct attribute_group *groups[7];

u16 reg_temp[5][NUM_TEMP]; /* 0=temp, 1=temp_over, 2=temp_hyst,
* 3=temp_crit, 4=temp_lcrit
@@ -1240,6 +1258,8 @@ struct nct6775_data {
const u16 *REG_ALARM;
const u16 *REG_BEEP;

+ const u16 *REG_TSI_TEMP;
+
unsigned int (*fan_from_reg)(u16 reg, unsigned int divreg);
unsigned int (*fan_from_reg_min)(u16 reg, unsigned int divreg);

@@ -1267,6 +1287,7 @@ struct nct6775_data {
s8 temp_offset[NUM_TEMP_FIXED];
s16 temp[5][NUM_TEMP]; /* 0=temp, 1=temp_over, 2=temp_hyst,
* 3=temp_crit, 4=temp_lcrit */
+ s16 tsi_temp[NUM_TSI_TEMP];
u64 alarms;
u64 beeps;

@@ -1315,6 +1336,7 @@ struct nct6775_data {

u16 have_temp;
u16 have_temp_fixed;
+ u16 have_tsi_temp;
u16 have_in;

/* Remember extra register values over suspend/resume */
@@ -1464,13 +1486,15 @@ static bool is_word_sized(struct nct6775_data *data, u16 reg)
switch (data->kind) {
case nct6106:
return reg == 0x20 || reg == 0x22 || reg == 0x24 ||
+ (reg >= 0x59 && reg < 0x69 && (reg & 1)) ||
reg == 0xe0 || reg == 0xe2 || reg == 0xe4 ||
reg == 0x111 || reg == 0x121 || reg == 0x131;
case nct6116:
return reg == 0x20 || reg == 0x22 || reg == 0x24 ||
- reg == 0x26 || reg == 0x28 || reg == 0xe0 || reg == 0xe2 ||
- reg == 0xe4 || reg == 0xe6 || reg == 0xe8 || reg == 0x111 ||
- reg == 0x121 || reg == 0x131 || reg == 0x191 || reg == 0x1a1;
+ reg == 0x26 || reg == 0x28 || reg == 0x59 || reg == 0x5b ||
+ reg == 0xe0 || reg == 0xe2 || reg == 0xe4 || reg == 0xe6 ||
+ reg == 0xe8 || reg == 0x111 || reg == 0x121 || reg == 0x131 ||
+ reg == 0x191 || reg == 0x1a1;
case nct6775:
return (((reg & 0xff00) == 0x100 ||
(reg & 0xff00) == 0x200) &&
@@ -1479,7 +1503,7 @@ static bool is_word_sized(struct nct6775_data *data, u16 reg)
(reg & 0x00ff) == 0x55)) ||
(reg & 0xfff0) == 0x630 ||
reg == 0x640 || reg == 0x642 ||
- reg == 0x662 ||
+ reg == 0x662 || reg == 0x669 ||
((reg & 0xfff0) == 0x650 && (reg & 0x000f) >= 0x06) ||
reg == 0x73 || reg == 0x75 || reg == 0x77;
case nct6776:
@@ -1490,6 +1514,7 @@ static bool is_word_sized(struct nct6775_data *data, u16 reg)
(reg & 0x00ff) == 0x55)) ||
(reg & 0xfff0) == 0x630 ||
reg == 0x402 ||
+ (reg >= 0x409 && reg < 0x419 && (reg & 1)) ||
reg == 0x640 || reg == 0x642 ||
((reg & 0xfff0) == 0x650 && (reg & 0x000f) >= 0x06) ||
reg == 0x73 || reg == 0x75 || reg == 0x77;
@@ -1504,6 +1529,7 @@ static bool is_word_sized(struct nct6775_data *data, u16 reg)
return reg == 0x150 || reg == 0x153 || reg == 0x155 ||
(reg & 0xfff0) == 0x4c0 ||
reg == 0x402 ||
+ (reg >= 0x409 && reg < 0x419 && (reg & 1)) ||
reg == 0x63a || reg == 0x63c || reg == 0x63e ||
reg == 0x640 || reg == 0x642 || reg == 0x64a ||
reg == 0x64c ||
@@ -1987,6 +2013,12 @@ static struct nct6775_data *nct6775_update_device(struct device *dev)
data->REG_TEMP_OFFSET[i]);
}

+ for (i = 0; i < NUM_TSI_TEMP; i++) {
+ if (!(data->have_tsi_temp & BIT(i)))
+ continue;
+ data->tsi_temp[i] = data->read_value(data, data->REG_TSI_TEMP[i]);
+ }
+
data->alarms = 0;
for (i = 0; i < NUM_REG_ALARM; i++) {
u8 alarm;
@@ -2670,6 +2702,44 @@ static const struct sensor_template_group nct6775_temp_template_group = {
.base = 1,
};

+static ssize_t show_tsi_temp(struct device *dev, struct device_attribute *attr, char *buf)
+{
+ struct nct6775_data *data = nct6775_update_device(dev);
+ struct sensor_device_attribute *sattr = to_sensor_dev_attr(attr);
+
+ return sysfs_emit(buf, "%u\n", tsi_temp_from_reg(data->tsi_temp[sattr->index]));
+}
+
+static ssize_t show_tsi_temp_label(struct device *dev, struct device_attribute *attr, char *buf)
+{
+ struct sensor_device_attribute *sattr = to_sensor_dev_attr(attr);
+
+ return sysfs_emit(buf, "TSI%d_TEMP\n", sattr->index);
+}
+
+SENSOR_TEMPLATE(tsi_temp_input, "temp%d_input", 0444, show_tsi_temp, NULL, 0);
+SENSOR_TEMPLATE(tsi_temp_label, "temp%d_label", 0444, show_tsi_temp_label, NULL, 0);
+
+static umode_t nct6775_tsi_temp_is_visible(struct kobject *kobj, struct attribute *attr,
+ int index)
+{
+ struct device *dev = kobj_to_dev(kobj);
+ struct nct6775_data *data = dev_get_drvdata(dev);
+ int temp = index / 2;
+
+ return (data->have_tsi_temp & BIT(temp)) ? attr->mode : 0;
+}
+
+/*
+ * The index calculation in nct6775_tsi_temp_is_visible() must be kept in
+ * sync with the size of this array.
+ */
+static struct sensor_device_template *nct6775_tsi_temp_template[] = {
+ &sensor_dev_template_tsi_temp_input,
+ &sensor_dev_template_tsi_temp_label,
+ NULL
+};
+
static ssize_t
show_pwm_mode(struct device *dev, struct device_attribute *attr, char *buf)
{
@@ -3948,10 +4018,11 @@ static int nct6775_probe(struct platform_device *pdev)
const u16 *reg_temp, *reg_temp_over, *reg_temp_hyst, *reg_temp_config;
const u16 *reg_temp_mon, *reg_temp_alternate, *reg_temp_crit;
const u16 *reg_temp_crit_l = NULL, *reg_temp_crit_h = NULL;
- int num_reg_temp, num_reg_temp_mon;
+ int num_reg_temp, num_reg_temp_mon, num_reg_tsi_temp;
u8 cr2a;
struct attribute_group *group;
struct device *hwmon_dev;
+ struct sensor_template_group tsi_temp_tg;
int num_attr_groups = 0;

if (sio_data->access == access_direct) {
@@ -4043,11 +4114,13 @@ static int nct6775_probe(struct platform_device *pdev)
data->ALARM_BITS = NCT6106_ALARM_BITS;
data->REG_BEEP = NCT6106_REG_BEEP;
data->BEEP_BITS = NCT6106_BEEP_BITS;
+ data->REG_TSI_TEMP = NCT6106_REG_TSI_TEMP;

reg_temp = NCT6106_REG_TEMP;
reg_temp_mon = NCT6106_REG_TEMP_MON;
num_reg_temp = ARRAY_SIZE(NCT6106_REG_TEMP);
num_reg_temp_mon = ARRAY_SIZE(NCT6106_REG_TEMP_MON);
+ num_reg_tsi_temp = ARRAY_SIZE(NCT6106_REG_TSI_TEMP);
reg_temp_over = NCT6106_REG_TEMP_OVER;
reg_temp_hyst = NCT6106_REG_TEMP_HYST;
reg_temp_config = NCT6106_REG_TEMP_CONFIG;
@@ -4116,11 +4189,13 @@ static int nct6775_probe(struct platform_device *pdev)
data->ALARM_BITS = NCT6116_ALARM_BITS;
data->REG_BEEP = NCT6106_REG_BEEP;
data->BEEP_BITS = NCT6116_BEEP_BITS;
+ data->REG_TSI_TEMP = NCT6116_REG_TSI_TEMP;

reg_temp = NCT6106_REG_TEMP;
reg_temp_mon = NCT6106_REG_TEMP_MON;
num_reg_temp = ARRAY_SIZE(NCT6106_REG_TEMP);
num_reg_temp_mon = ARRAY_SIZE(NCT6106_REG_TEMP_MON);
+ num_reg_tsi_temp = ARRAY_SIZE(NCT6116_REG_TSI_TEMP);
reg_temp_over = NCT6106_REG_TEMP_OVER;
reg_temp_hyst = NCT6106_REG_TEMP_HYST;
reg_temp_config = NCT6106_REG_TEMP_CONFIG;
@@ -4191,11 +4266,13 @@ static int nct6775_probe(struct platform_device *pdev)
data->REG_WEIGHT_TEMP[2] = NCT6775_REG_WEIGHT_TEMP_BASE;
data->REG_ALARM = NCT6775_REG_ALARM;
data->REG_BEEP = NCT6775_REG_BEEP;
+ data->REG_TSI_TEMP = NCT6775_REG_TSI_TEMP;

reg_temp = NCT6775_REG_TEMP;
reg_temp_mon = NCT6775_REG_TEMP_MON;
num_reg_temp = ARRAY_SIZE(NCT6775_REG_TEMP);
num_reg_temp_mon = ARRAY_SIZE(NCT6775_REG_TEMP_MON);
+ num_reg_tsi_temp = ARRAY_SIZE(NCT6775_REG_TSI_TEMP);
reg_temp_over = NCT6775_REG_TEMP_OVER;
reg_temp_hyst = NCT6775_REG_TEMP_HYST;
reg_temp_config = NCT6775_REG_TEMP_CONFIG;
@@ -4264,11 +4341,13 @@ static int nct6775_probe(struct platform_device *pdev)
data->REG_WEIGHT_TEMP[2] = NCT6775_REG_WEIGHT_TEMP_BASE;
data->REG_ALARM = NCT6775_REG_ALARM;
data->REG_BEEP = NCT6776_REG_BEEP;
+ data->REG_TSI_TEMP = NCT6776_REG_TSI_TEMP;

reg_temp = NCT6775_REG_TEMP;
reg_temp_mon = NCT6775_REG_TEMP_MON;
num_reg_temp = ARRAY_SIZE(NCT6775_REG_TEMP);
num_reg_temp_mon = ARRAY_SIZE(NCT6775_REG_TEMP_MON);
+ num_reg_tsi_temp = ARRAY_SIZE(NCT6776_REG_TSI_TEMP);
reg_temp_over = NCT6775_REG_TEMP_OVER;
reg_temp_hyst = NCT6775_REG_TEMP_HYST;
reg_temp_config = NCT6776_REG_TEMP_CONFIG;
@@ -4341,11 +4420,13 @@ static int nct6775_probe(struct platform_device *pdev)
data->REG_WEIGHT_TEMP[2] = NCT6775_REG_WEIGHT_TEMP_BASE;
data->REG_ALARM = NCT6779_REG_ALARM;
data->REG_BEEP = NCT6776_REG_BEEP;
+ data->REG_TSI_TEMP = NCT6776_REG_TSI_TEMP;

reg_temp = NCT6779_REG_TEMP;
reg_temp_mon = NCT6779_REG_TEMP_MON;
num_reg_temp = ARRAY_SIZE(NCT6779_REG_TEMP);
num_reg_temp_mon = ARRAY_SIZE(NCT6779_REG_TEMP_MON);
+ num_reg_tsi_temp = ARRAY_SIZE(NCT6776_REG_TSI_TEMP);
reg_temp_over = NCT6779_REG_TEMP_OVER;
reg_temp_hyst = NCT6779_REG_TEMP_HYST;
reg_temp_config = NCT6779_REG_TEMP_CONFIG;
@@ -4460,6 +4541,24 @@ static int nct6775_probe(struct platform_device *pdev)
data->REG_BEEP = NCT6776_REG_BEEP;
else
data->REG_BEEP = NCT6792_REG_BEEP;
+ switch (data->kind) {
+ case nct6791:
+ case nct6792:
+ case nct6793:
+ data->REG_TSI_TEMP = NCT6776_REG_TSI_TEMP;
+ num_reg_tsi_temp = ARRAY_SIZE(NCT6776_REG_TSI_TEMP);
+ break;
+ case nct6795:
+ case nct6796:
+ case nct6797:
+ case nct6798:
+ data->REG_TSI_TEMP = NCT6796_REG_TSI_TEMP;
+ num_reg_tsi_temp = ARRAY_SIZE(NCT6796_REG_TSI_TEMP);
+ break;
+ default:
+ num_reg_tsi_temp = 0;
+ break;
+ }

reg_temp = NCT6779_REG_TEMP;
num_reg_temp = ARRAY_SIZE(NCT6779_REG_TEMP);
@@ -4659,6 +4758,12 @@ static int nct6775_probe(struct platform_device *pdev)
}
#endif /* USE_ALTERNATE */

+ /* Check which TSIx_TEMP registers are active */
+ for (i = 0; i < num_reg_tsi_temp; i++) {
+ if (data->read_value(data, data->REG_TSI_TEMP[i]))
+ data->have_tsi_temp |= BIT(i);
+ }
+
/* Initialize the chip */
nct6775_init_device(data);

@@ -4766,6 +4871,18 @@ static int nct6775_probe(struct platform_device *pdev)
return PTR_ERR(group);

data->groups[num_attr_groups++] = group;
+
+ if (data->have_tsi_temp) {
+ tsi_temp_tg.templates = nct6775_tsi_temp_template;
+ tsi_temp_tg.is_visible = nct6775_tsi_temp_is_visible;
+ tsi_temp_tg.base = fls(data->have_temp) + 1;
+ group = nct6775_create_attr_group(dev, &tsi_temp_tg, fls(data->have_tsi_temp));
+ if (IS_ERR(group))
+ return PTR_ERR(group);
+
+ data->groups[num_attr_groups++] = group;
+ }
+
data->groups[num_attr_groups++] = &nct6775_group_other;

hwmon_dev = devm_hwmon_device_register_with_groups(dev, data->name,
--
2.34.1