Re: [PATCH v2 25/27] nvdimm/ocxl: Expose SMART data via ndctl

[Alastair D'Silva]

On Tue, 2019-12-03 at 14:46 +1100, Alastair D'Silva wrote:
> From: Alastair D'Silva <alastair@xxxxxxxxxxx>
> 
> This patch retrieves proprietary formatted SMART data and makes it
> available via ndctl. A later contribution will be made to ndctl to
> parse this data.
> 
> Signed-off-by: Alastair D'Silva <alastair@xxxxxxxxxxx>

Dan,

I should ask, is there a defined format that ND_CMD_SMART should be
returning data in, or is it reasonable to have this implementation
dependent?


> ---
>  drivers/nvdimm/ocxl/scm.c          | 156
> +++++++++++++++++++++++++++++
>  drivers/nvdimm/ocxl/scm_internal.h |  21 ++++
>  2 files changed, 177 insertions(+)
> 
> diff --git a/drivers/nvdimm/ocxl/scm.c b/drivers/nvdimm/ocxl/scm.c
> index 8deb7862793c..77b9e68870a3 100644
> --- a/drivers/nvdimm/ocxl/scm.c
> +++ b/drivers/nvdimm/ocxl/scm.c
> @@ -94,6 +94,157 @@ static int scm_ndctl_config_size(struct
> nd_cmd_get_config_size *command)
>  	return 0;
>  }
>  
> +static int read_smart_attrib(struct scm_data *scm_data, u16 offset,
> +			     struct scm_smart_attribs *attribs)
> +{
> +	u64 val;
> +	int rc;
> +	struct scm_smart_attrib *attrib;
> +	u8 attrib_id;
> +
> +	rc = ocxl_global_mmio_read64(scm_data->ocxl_afu, offset,
> OCXL_LITTLE_ENDIAN,
> +				     &val);
> +	if (rc)
> +		return rc;
> +
> +	attrib_id = (val >> 56) & 0xff;
> +	switch (attrib_id) {
> +	case SCM_SMART_ATTR_POWER_ON_HOURS:
> +		attrib = &attribs->power_on_hours;
> +		break;
> +
> +	case SCM_SMART_ATTR_TEMPERATURE:
> +		attrib = &attribs->temperature;
> +		break;
> +
> +	case SCM_SMART_ATTR_LIFE_REMAINING:
> +		attrib = &attribs->life_remaining;
> +		break;
> +
> +	default:
> +		dev_warn(&scm_data->dev, "Unknown smart attrib '%d'",
> attrib_id);
> +		return -ENOENT;
> +	}
> +
> +	attrib->id = attrib_id;
> +	attrib->attribute_flags = (val >> 40) & 0xffff;
> +	attrib->current_val = (val >> 32) & 0xff;
> +	attrib->threshold_val = (val >> 24) & 0xff;
> +	attrib->worst_val = (val >> 16) & 0xff;
> +
> +	rc = ocxl_global_mmio_read64(scm_data->ocxl_afu, offset + 0x08,
> +				     OCXL_LITTLE_ENDIAN, &val);
> +	if (rc)
> +		return rc;
> +
> +	attrib->raw_val = val;
> +
> +	return 0;
> +}
> +
> +/**
> + * scm_smart_header_parse() - Parse the first 64 bits of the SMART
> admin command response
> + * @scm_data: the SCM metadata
> + * @length: out, returns the number of bytes in the response
> (excluding the 64 bit header)
> + */
> +static int scm_smart_header_parse(struct scm_data *scm_data, u32
> *length)
> +{
> +	int rc;
> +	u64 val;
> +
> +	u16 data_identifier;
> +	u32 data_length;
> +
> +	rc = ocxl_global_mmio_read64(scm_data->ocxl_afu,
> +				     scm_data-
> >admin_command.data_offset,
> +				     OCXL_LITTLE_ENDIAN, &val);
> +	if (rc)
> +		return rc;
> +
> +	data_identifier = val >> 48;
> +	data_length = val & 0xFFFFFFFF;
> +
> +	if (data_identifier != 0x534D) {
> +		dev_err(&scm_data->dev,
> +			"Bad data identifier for smart data, expected
> 'SM', got '%-.*s'\n",
> +			2, (char *)&data_identifier);
> +		return -EINVAL;
> +	}
> +
> +	*length = data_length;
> +	return 0;
> +}
> +
> +static int scm_smart_update(struct scm_data *scm_data)
> +{
> +	u32 length, i;
> +	int rc;
> +
> +	mutex_lock(&scm_data->admin_command.lock);
> +
> +	rc = scm_admin_command_request(scm_data, ADMIN_COMMAND_SMART);
> +	if (rc)
> +		goto out;
> +
> +	rc = scm_admin_command_execute(scm_data);
> +	if (rc)
> +		goto out;
> +
> +	rc = scm_admin_command_complete_timeout(scm_data,
> ADMIN_COMMAND_SMART);
> +	if (rc < 0) {
> +		dev_err(&scm_data->dev, "SMART timeout\n");
> +		goto out;
> +	}
> +
> +	rc = scm_admin_response(scm_data);
> +	if (rc < 0)
> +		goto out;
> +	if (rc != STATUS_SUCCESS) {
> +		scm_warn_status(scm_data, "Unexpected status from
> SMART", rc);
> +		goto out;
> +	}
> +
> +	rc = scm_smart_header_parse(scm_data, &length);
> +	if (rc)
> +		goto out;
> +
> +	length /= 0x10; // Length now contains the number of attributes
> +
> +	for (i = 0; i < length; i++)
> +		read_smart_attrib(scm_data,
> +				  scm_data->admin_command.data_offset +
> 0x08 + i * 0x10,
> +				  &scm_data->smart);
> +
> +	rc = scm_admin_response_handled(scm_data);
> +	if (rc)
> +		goto out;
> +
> +	rc = 0;
> +	goto out;
> +
> +out:
> +	mutex_unlock(&scm_data->admin_command.lock);
> +	return rc;
> +}
> +
> +static int scm_ndctl_smart(struct scm_data *scm_data, void *buf,
> +			   unsigned int buf_len)
> +{
> +	int rc;
> +
> +	if (buf_len != sizeof(scm_data->smart))
> +		return -EINVAL;
> +
> +	rc = scm_smart_update(scm_data);
> +	if (rc)
> +		return rc;
> +
> +	memcpy(buf, &scm_data->smart, buf_len);
> +
> +	return 0;
> +}
> +
> +
>  static int scm_ndctl(struct nvdimm_bus_descriptor *nd_desc,
>  		     struct nvdimm *nvdimm,
>  		     unsigned int cmd, void *buf, unsigned int buf_len,
> int *cmd_rc)
> @@ -101,6 +252,10 @@ static int scm_ndctl(struct
> nvdimm_bus_descriptor *nd_desc,
>  	struct scm_data *scm_data = container_of(nd_desc, struct
> scm_data, bus_desc);
>  
>  	switch (cmd) {
> +	case ND_CMD_SMART:
> +		*cmd_rc = scm_ndctl_smart(scm_data, buf, buf_len);
> +		return 0;
> +
>  	case ND_CMD_GET_CONFIG_SIZE:
>  		*cmd_rc = scm_ndctl_config_size(buf);
>  		return 0;
> @@ -300,6 +455,7 @@ static int scm_register_lpc_mem(struct scm_data
> *scm_data)
>  	set_bit(ND_CMD_GET_CONFIG_SIZE, &nvdimm_cmd_mask);
>  	set_bit(ND_CMD_GET_CONFIG_DATA, &nvdimm_cmd_mask);
>  	set_bit(ND_CMD_SET_CONFIG_DATA, &nvdimm_cmd_mask);
> +	set_bit(ND_CMD_SMART, &nvdimm_cmd_mask);
>  
>  	set_bit(NDD_ALIASING, &nvdimm_flags);
>  
> diff --git a/drivers/nvdimm/ocxl/scm_internal.h
> b/drivers/nvdimm/ocxl/scm_internal.h
> index 4a29088612a9..d593fefe38d5 100644
> --- a/drivers/nvdimm/ocxl/scm_internal.h
> +++ b/drivers/nvdimm/ocxl/scm_internal.h
> @@ -115,6 +115,26 @@ enum overwrite_state {
>  	SCM_OVERWRITE_FAILED
>  };
>  
> +#define SCM_SMART_ATTR_POWER_ON_HOURS	0x09
> +#define SCM_SMART_ATTR_TEMPERATURE	0xC2
> +#define SCM_SMART_ATTR_LIFE_REMAINING	0xCA
> +
> +struct scm_smart_attrib {
> +	__u8 id; /* See defines above */
> +	__u16 attribute_flags;
> +	__u8 current_val;
> +	__u8 threshold_val;
> +	__u8 worst_val;
> +	__u8 reserved;
> +	__u64 raw_val;
> +};
> +
> +struct scm_smart_attribs {
> +	struct scm_smart_attrib power_on_hours;
> +	struct scm_smart_attrib temperature;
> +	struct scm_smart_attrib life_remaining;
> +};
> +
>  struct scm_data {
>  	struct device dev;
>  	struct pci_dev *pdev;
> @@ -136,6 +156,7 @@ struct scm_data {
>  	struct resource scm_res;
>  	struct nd_region *nd_region;
>  	struct eventfd_ctx *ev_ctx;
> +	struct scm_smart_attribs smart;
>  	char fw_version[8+1];
>  	u32 timeouts[ADMIN_COMMAND_MAX+1];
>  
-- 
Alastair D'Silva
Open Source Developer
Linux Technology Centre, IBM Australia
mob: 0423 762 819