NAME

ufm — Upgradeable Firmware Module driver

SYNOPSIS

/dev/ufm

#include <sys/ddi_ufm.h>

DESCRIPTION

The ufm device is a character special file that provides access to Upgradeable Firmware Image information, as described in ddi_ufm(9E) via a private ioctl interface.

The UFM interfaces described below are used in the implementation of the system through tools such as fwflash(8) or as part of the fault management architecture.

FILES

/kernel/drv/amd64/ufm: 64-bit AMD64 ELF kernel driver
/kernel/drv/sparcv9/ufm: 64-bit SPARC ELF kernel driver

IOCTLS

The ufm driver implements a versioned ioctl interface for accessing UFM facilities. The ioctl interfaces are defined in sys/ddi_ufm.h. The following ioctl cmds are supported by DDI_UFM_VERSION_ONE:

UFM_IOC_GETCAPS

The UFM_IOC_GETCAPS ioctl is used to retrieve the set of DDI UFM capabilities supported by this device instance.

The ddi_ufm_cap_t type defines a bitfield enumerating the full set of DDI UFM capabilities.

typedef enum {
	DDI_UFM_CAP_REPORT	= 1 << 0,
	DDI_UFM_CAP_READIMG	= 1 << 1
} ddi_ufm_cap_t;

The capabilities mean:

DDI_UFM_CAP_REPORT: Indicates that the device is capable of reporting UFM information and supports the UFM_IOC_REPORT and UFM_IOC_REPORTSZ ioctls.
DDI_UFM_CAP_READIMG: Indicates that the device is capable of retrieving a firmware image from a slot and transferring it back to the caller. The UFM_IOC_READIMG ioctl is supported.

The ufm_ioc_getcaps_t structure defines the input/output data for the UFM_IOC_GETCAPS ioctl. Callers should specify the ufmg_version and ufmg_devpath fields. On success the ufmg_caps field will be filled in with a value indicating the supported UFM capabilities of the device specified in ufmg_devpath.

typedef struct ufm_ioc_getcaps {
	uint_t		ufmg_version;	/* DDI_UFM_VERSION_ONE */
	uint_t		ufmg_caps;	/* UFM Caps */
	char		ufmg_devpath[MAXPATHLEN];
} ufm_ioc_getcaps_t;

UFM_IOC_REPORTSZ

The UFM_IOC_REPORTSZ ioctl is used to retrieve the amount of space (in bytes) required to hold the UFM data for this device instance. This should be used to allocate a sufficiently sized buffer for the UFM_IOC_REPORT ioctl.

The ufm_ioc_bufsz_t structure defines the input/output data for the UFM_IOC_REPORTSZ ioctl. Callers should specify the ufbz_version and ufbz_devpath fields. On success the ufbz_size field will be filled in with the required buffer size.

typedef struct ufm_ioc_bufsz {
	uint_t		ufbz_version;	/* DDI_UFM_VERSION_ONE */
	size_t		ufbz_size;	/* sz of buf to be returned by ioctl */
	char		ufbz_devpath[MAXPATHLEN];
} ufm_ioc_bufsz_t;

UFM_IOC_REPORT

The UFM_IOC_REPORT ioctl returns UFM image and slot data in the form of a packed nvlist. The ufm_ioc_report_t structure defines the input/output data for the UFM_IOC_REPORT ioctl. Callers should specify the ufmr_version, ufmr_bufsz and ufmr_devpath fields. On success, the ufmr_buf field will point to a packed nvlist containing the UFM data for the specified device instance. This data can be unpacked and decoded into an nvlist using nvlist_unpack(3NVPAIR).

typedef struct ufm_ioc_report {
	uint_t		ufmr_version;	/* DDI_UFM_VERSIONONE */
	size_t		ufmr_bufsz;	/* size of caller-supplied buffer */
	caddr_t		ufmr_buf;	/* buf to hold packed output nvl */
	char		ufmr_devpath[MAXPATHLEN];
} ufm_ioc_report_t;

Due to the asynchronous nature of the system, it's possible for a device to undergo a configuration change in between a UFM_IOC_REPORTSZ ioctl and a subsequent UFM_IOC_REPORT ioctl that would alter the size of the buffer required to hold the UFM data.

If the size of buffer supplied in the UFM_IOC_REPORT ioctl is greater than is required to hold the UFM data, then the ioctl will succeed and the ufmr_bufsz field will be updated to reflect the actual size of the returned UFM data. If the size of buffer supplied in the UFM_IOC_REPORT ioctl is less than what is required to hold the UFM data, the ioctl will fail with errno set to EOVERFLOW.

UFM_IOC_READIMG

The UFM_IOC_READIMG ioctl retrieves a firmware image and slot from a device. The ufm_ioc_readimg_t structure defines the input and output data for the ioctl. Devices may have their own alignment and size constraints which may be enforced upon issuing this ioctl. The structure has the following form:

typedef struct ufm_ioc_readimg {
	uint_t		ufri_version;
	uint_t		ufri_imageno;
	uint_t		ufri_slotno;
	uint64_t	ufri_offset;
	uint64_t	ufri_len;
	uint64_t	ufri_nread;
	void		*ufri_buf;
	char		ufri_devpath[MAXPATHLEN];
} ufm_ioc_readimg_t;

The ufri_imageno and ufri_slotno values are used to indicate the image and slot to read. These indexes correspond to the same indices that are returned in the nvlist from the UFM_IOC_REPORT ioctl. The ufri_offset and ufri_len members are used to indicate how many bytes to read from the image and where in the image to begin. The ufri_buf member must be set to a valid pointer. Data read from the device will be placed in that pointer. The pointer must be at least ufri_len bytes long. Upon successful completion, the ufri_nread member will be filled in with the number of bytes that have been placed in ufri_buf. Finally, the ufri_version and ufri_devpath fields must be filled in with the version number, DDI_UFM_VERSION_ONE, and the corresponding /devices path.

EXAMPLES

This example demonstrates how to use the UFM_IOC_GETCAPS ioctl to determine the UFM capabilities of a given device instance.

#include <stdio.h>
#include <stdlib.h>
#include <errno.h>
#include <fcntl.h>
#include <string.h>
#include <unistd.h>
#include <sys/ddi_ufm.h>
#include <sys/types.h>

static const char devname[] = "/pci@ce,0/pci8086,2030@0/pci15d9,808@0";

int
main(int argc, char **argv)
{
        int fd;
        ufm_ioc_getcaps_t ioc = { 0 };

        if ((fd = open(DDI_UFM_DEV, O_RDWR)) < 0) {
                (void) fprintf(stderr, "failed to open %s (%s)0, DDI_UFM_DEV,
                    strerror(errno));
                return (1);
        }

        ioc.ufmg_version = DDI_UFM_CURRENT_VERSION;
        (void) strcpy(ioc.ufmg_devpath, devname);

        if (ioctl(fd, UFM_IOC_GETCAPS, &ioc) < 0) {
                (void) fprintf(stderr, "getcaps ioctl failed (%s)0,
                    strerror(errno));
                (void) close(fd);
                return (1);
        }
        if ((ioc.ufmg_caps & DDI_UFM_CAP_REPORT) == 0) {
                (void) printf("Driver does not support DDI_UFM_CAP_REPORT0);
        } else {
                (void) printf("Driver supports DDI_UFM_CAP_REPORT0);
        }
        (void) close(fd);
        return (0);
}

ERRORS

On failure to open or perform ioctls to the ufm driver, errno will be set to indicate the type of error. A subset of the more common errors are detailed below. For a full list of error numbers, see Intro(2)

EAGAIN: The device driver is not currently ready to accept calls to it's DDI UFM entry points. This may be because the driver is not fully initialized or because the driver is in the process of detaching.
EFAULT: The ufm driver encountered a failure while copying data either from or to the address space of the calling process.
EINVAL: The offset or length of an image would have resulted in a read outside of the image's valid range or with improper alignment.
EIO: A failure occurred while executing a DDI UFM entry point.
ENOTSUP: Either the requested ioctl is not supported by the target device, the device does not exist or the device does not support the UFM interfaces.

INTERFACE STABILITY

Evolving