Re: [PATCH 3/5] hwmon: (socfpga) Add hardware monitoring support on SoCFPGA platforms
From: Dinh Nguyen
Date: Tue Apr 18 2023 - 13:29:49 EST
On 4/17/2023 4:51 PM, Guenter Roeck wrote:
On 4/17/23 13:55, Dinh Nguyen wrote:
On 4/10/2023 9:44 PM, Guenter Roeck wrote:
On 4/10/23 08:33, dinh.nguyen@xxxxxxxxxxxxxxx wrote:
From: Dinh Nguyen <dinh.nguyen@xxxxxxxxxxxxxxx>
The driver supports 64-bit SoCFPGA platforms for temperature and
voltage
reading using the platform's SDM(Secure Device Manager). The driver
also uses the Stratix10 Service layer driver.
This driver only supports OF SoCFPGA 64-bit platforms.
Reviewed-by: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx>
Signed-off-by: Dinh Nguyen <dinh.nguyen@xxxxxxxxxxxxxxx>
---
Documentation/hwmon/index.rst | 1 +
Documentation/hwmon/socfpga-hwmon.rst | 30 ++
drivers/firmware/stratix10-svc.c | 18 +-
Changes outside the hwmon subsystem need to be in a separate patch.
will separate...
drivers/hwmon/Kconfig | 11 +
drivers/hwmon/Makefile | 1 +
drivers/hwmon/socfpga-hwmon.c | 406
++++++++++++++++++
include/linux/firmware/intel/stratix10-smc.h | 34 ++
.../firmware/intel/stratix10-svc-client.h | 6 +
8 files changed, 506 insertions(+), 1 deletion(-)
create mode 100644 Documentation/hwmon/socfpga-hwmon.rst
create mode 100644 drivers/hwmon/socfpga-hwmon.c
...
+
+enum hwmon_type_op {
+ SOCFPGA_HWMON_TYPE_TEMP,
+ SOCFPGA_HWMON_TYPE_VOLT,
+ SOCFPGA_HWMON_TYPE_MAX
Unused define
Removed.
+};
+
+static const char *const hwmon_types_str[] = { "temperature",
"voltage" };
+
+static umode_t socfpga_is_visible(const void *dev,
+ enum hwmon_sensor_types type,
+ u32 attr, int chan)
+{
+ switch (type) {
+ case hwmon_temp:
+ case hwmon_in:
+ return 0444;
+ default:
+ return 0;
+ }
+}
+
+static void socfpga_smc_callback(struct stratix10_svc_client *client,
+ struct stratix10_svc_cb_data *data)
+{
+ struct socfpga_hwmon_priv *priv = client->priv;
+ struct arm_smccc_res *res = data->kaddr1;
+
+ if (data->status == BIT(SVC_STATUS_OK)) {
+ if (priv->msg.command == COMMAND_HWMON_READTEMP)
+ priv->temperature.value = res->a0;
+ else
+ priv->voltage.value = res->a0;
+ } else
+ dev_err(client->dev, "%s returned 0x%lX\n", __func__,
res->a0);
+
Missing { } in else branch. Please run checkpatch --strict and fix
continuation line alignment issues as well as unbalanced if/else
reports.
Will do.
+ complete(&priv->completion);
+}
+
+static int socfpga_hwmon_send(struct socfpga_hwmon_priv *priv)
+{
+ int ret;
+
+ priv->client.receive_cb = socfpga_smc_callback;
+
+ ret = stratix10_svc_send(priv->chan, &priv->msg);
+ if (ret < 0)
+ return ret;
+
+ if (!wait_for_completion_timeout(&priv->completion,
HWMON_TIMEOUT)) {
+ dev_err(priv->client.dev, "SMC call timeout!\n");
+ return -ETIMEDOUT;
+ }
+
+ return 0;
+}
+
+static int socfpga_hwmon_err_to_errno(struct socfpga_hwmon_priv
*priv)
+{
+ int value = priv->temperature.value;
+
+ if (!(value & ETEMP_ERROR))
+ return 0;
+
This is odd. int is normally 32 bit, this function is called from
socfpga_read() for temperatures, which presumably are defined
as "signed 32-bit fixed point binary". That means that negative
temperatures would be treated as errors. Please verify.
That's correct, if bit 31 is set, then it indicates an error.
This ...
+ dev_err(priv->client.dev, "temperature sensor code 0x%08x\n",
value);
+
Please don't clog the log with such messages.
Removed.
+ value &= ~ETEMP_ERROR;
+ switch (value) {
+ case ETEMP_NOT_PRESENT:
+ return -ENOENT;
+ case ETEMP_CORRUPT:
+ case ETEMP_NOT_INITIALIZED:
+ return -ENODATA;
+ case ETEMP_BUSY:
+ return -EBUSY;
+ case ETEMP_INACTIVE:
+ case ETEMP_TIMEOUT:
+ case ETEMP_TOO_OLD:
+ return -EAGAIN;
+ default:
+ /* Unknown error */
+ return -EINVAL;
Should be -EIO.
Replaced.
+ }
+}
+
+static int socfpga_read(struct device *dev, enum
hwmon_sensor_types type,
+ u32 attr, int chan, long *val)
+{
+ struct socfpga_hwmon_priv *priv = dev_get_drvdata(dev);
+ int ret;
+
+ mutex_lock(&priv->lock);
+ reinit_completion(&priv->completion);
+
+ switch (type) {
+ case hwmon_temp:
+ priv->msg.arg[0] = BIT_ULL(priv->temperature.chan[chan]);
+ priv->msg.command = COMMAND_HWMON_READTEMP;
+ if (socfpga_hwmon_send(priv))
+ goto status_done;
+
+ ret = socfpga_hwmon_err_to_errno(priv);
+ if (ret)
+ break;
+ /*
+ * The Temperature Sensor IP core returns the Celsius
+ * temperature value in signed 32-bit fixed point binary
... and this contradict each other. If bit 31 indicates an error,
this can not be a signed 32-bit value.
You're right! I've re-read the spec and should have the the code look
for the specific error values:
0x80000000 - inactive
0x80000001 - old value
0x80000002 - invalid channel
0x80000003 - corrupted.
...
Dinh