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_MAXUnused 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.
+ 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 + * format, with eight bits below binary point. + */+ *val = (priv->temperature.value * MILLIDEGREE_PER_DEGREE) / 256;+ break; + case hwmon_in: /* Read voltage */Pointless comment
Removed.
There are no error readings for the voltage sensors specified in the spec. Will update+ priv->msg.arg[0] = BIT_ULL(priv->voltage.chan[chan]); + priv->msg.command = COMMAND_HWMON_READVOLT; + if (socfpga_hwmon_send(priv)) + goto status_done; +No error check for voltage sensors ? Also, unless I am missing something, the error bailout leaves ret undefined.
the ret value.
+ /* + * The Voltage Sensor IP core returns the sampled voltage + * in unsigned 32-bit fixed point binary format, with 16 bits + * below binary point. + */ + *val = (priv->voltage.value * MILLIVOLT_PER_VOLT) / 65536; + break; + default: + ret = -EOPNOTSUPP; + break; + } + +status_done: + stratix10_svc_done(priv->chan); + mutex_unlock(&priv->lock); + return ret; +} + +static int socfpga_read_string(struct device *dev, + enum hwmon_sensor_types type, u32 attr, + int chan, const char **str) +{ + struct socfpga_hwmon_priv *priv = dev_get_drvdata(dev); + + switch (type) { + case hwmon_in: + *str = priv->voltage.names[chan]; + return 0; + case hwmon_temp: + *str = priv->temperature.names[chan]; + return 0; + default: + return -EOPNOTSUPP; + } +} + +static const struct hwmon_ops socfpga_ops = { + .is_visible = socfpga_is_visible, + .read = socfpga_read, + .read_string = socfpga_read_string, +}; + +static const struct hwmon_channel_info *socfpga_info[] = { + HWMON_CHANNEL_INFO(temp, + HWMON_T_INPUT | HWMON_T_LABEL, HWMON_T_INPUT | HWMON_T_LABEL, + HWMON_T_INPUT | HWMON_T_LABEL, HWMON_T_INPUT | HWMON_T_LABEL, + HWMON_T_INPUT | HWMON_T_LABEL, HWMON_T_INPUT | HWMON_T_LABEL, + HWMON_T_INPUT | HWMON_T_LABEL, HWMON_T_INPUT | HWMON_T_LABEL, + HWMON_T_INPUT | HWMON_T_LABEL, HWMON_T_INPUT | HWMON_T_LABEL, + HWMON_T_INPUT | HWMON_T_LABEL, HWMON_T_INPUT | HWMON_T_LABEL, + HWMON_T_INPUT | HWMON_T_LABEL, HWMON_T_INPUT | HWMON_T_LABEL, + HWMON_T_INPUT | HWMON_T_LABEL, HWMON_T_INPUT | HWMON_T_LABEL), + HWMON_CHANNEL_INFO(in, + HWMON_I_INPUT | HWMON_I_LABEL, HWMON_I_INPUT | HWMON_I_LABEL, + HWMON_I_INPUT | HWMON_I_LABEL, HWMON_I_INPUT | HWMON_I_LABEL, + HWMON_I_INPUT | HWMON_I_LABEL, HWMON_I_INPUT | HWMON_I_LABEL, + HWMON_I_INPUT | HWMON_I_LABEL, HWMON_I_INPUT | HWMON_I_LABEL, + HWMON_I_INPUT | HWMON_I_LABEL, HWMON_I_INPUT | HWMON_I_LABEL, + HWMON_I_INPUT | HWMON_I_LABEL, HWMON_I_INPUT | HWMON_I_LABEL, + HWMON_I_INPUT | HWMON_I_LABEL, HWMON_I_INPUT | HWMON_I_LABEL, + HWMON_I_INPUT | HWMON_I_LABEL, HWMON_I_INPUT | HWMON_I_LABEL), + NULL +}; + +static const struct hwmon_chip_info socfpga_chip_info = { + .ops = &socfpga_ops, + .info = socfpga_info, +}; + +static int socfpga_add_channel(struct device *dev, const char *type, + u32 val, const char *label, + struct socfpga_hwmon_priv *priv) +{ + int type_index; + struct socfpga_hwmon_chan *p; ++ type_index = match_string(hwmon_types_str, ARRAY_SIZE(hwmon_types_str), type);+ switch (type_index) { + case SOCFPGA_HWMON_TYPE_TEMP: + p = &priv->temperature; + break; + case SOCFPGA_HWMON_TYPE_VOLT: + p = &priv->voltage; + break; + default: + return -ENODATA; + } + if (p->n >= SOCFPGA_HWMON_MAXSENSORS) + return -ENOSPC; + + p->names[p->n] = label; + p->chan[p->n] = val; + p->n++; + + return 0; +} + +static int socfpga_probe_child_from_dt(struct device *dev, + struct device_node *child, + struct socfpga_hwmon_priv *priv) +{ + struct device_node *grandchild; + const char *label; + const char *type; + u32 val; + int ret; + + if (of_property_read_string(child, "name", &type))+ return dev_err_probe(dev, -EINVAL, "No type for %pOF\n", child);+ + for_each_child_of_node(child, grandchild) { + ret = of_property_read_u32(grandchild, "reg", &val); + if (ret)+ return dev_err_probe(dev, ret, "missing reg property of %pOF\n",+ grandchild); + + ret = of_property_read_string(grandchild, "label", &label); + if (ret)+ return dev_err_probe(dev, ret, "missing label propoerty of %pOF\n",+ grandchild); + ret = socfpga_add_channel(dev, type, val, label, priv); + if (ret == -ENOSPC)+ return dev_err_probe(dev, ret, "too many channels, only %d supported\n",+ SOCFPGA_HWMON_MAXSENSORS); + } + return 0; +} + +static int socfpga_probe_from_dt(struct device *dev, + struct socfpga_hwmon_priv *priv) +{ + const struct device_node *np = dev->of_node; + struct device_node *child; + int ret = 0; + + for_each_child_of_node(np, child) { + ret = socfpga_probe_child_from_dt(dev, child, priv); + if (ret) + break; + } + of_node_put(child); + + return ret; +} + +static int socfpga_hwmon_probe(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + struct device *hwmon_dev; + struct socfpga_hwmon_priv *priv; + int ret; + + priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL); + if (!priv) + return -ENOMEM; + + priv->client.dev = dev; + priv->client.priv = priv; + + ret = socfpga_probe_from_dt(dev, priv); + if (ret)+ return dev_err_probe(dev, ret, "Unable to probe from device tree\n");+ + mutex_init(&priv->lock); + init_completion(&priv->completion);+ hwmon_dev = devm_hwmon_device_register_with_info(dev, "socfpgahwmon",+ priv, + &socfpga_chip_info, + NULL); + if (IS_ERR(hwmon_dev)) + return PTR_ERR(hwmon_dev); + + priv->chan = stratix10_svc_request_channel_byname(&priv->client, + SVC_CLIENT_HWMON);This is racy: hwmon attributes exist here, and priv->chan may be accessed beforeit is set.
Fixed in v2.
+ if (IS_ERR(priv->chan)) + return dev_err_probe(dev, PTR_ERR(priv->chan), + "couldn't get service channel %s\n", + SVC_CLIENT_RSU); + + platform_set_drvdata(pdev, priv); + + return 0; +} + +static int socfpga_hwmon_remove(struct platform_device *pdev) +{ + struct socfpga_hwmon_priv *priv = platform_get_drvdata(pdev); + + stratix10_svc_free_channel(priv->chan);This releases the channel before the hwmon device is released. Another race condition.
fixed in V2. Thanks for the review! Dinh
