Dell Systems Management Base Driver

Overview

The Dell Systems Management Base Driver provides a sysfs interface forsystems management software such as Dell OpenManage to perform systemmanagement interrupts and host control actions (system power cycle orpower off after OS shutdown) on certain Dell systems.

Dell OpenManage requires this driver on the following Dell PowerEdge systems:300, 1300, 1400, 400SC, 500SC, 1500SC, 1550, 600SC, 1600SC, 650, 1655MC,700, and 750. Other Dell software such as the open source libsmbios projectis expected to make use of this driver, and it may include the use of thisdriver on other Dell systems.

The Dell libsmbios project aims towards providing access to as much BIOSinformation as possible. Seehttp://linux.dell.com/libsmbios/main/ formore information about the libsmbios project.

System Management Interrupt

On some Dell systems, systems management software must access certainmanagement information via a system management interrupt (SMI). The SMI databuffer must reside in 32-bit address space, and the physical address of thebuffer is required for the SMI. The driver maintains the memory required forthe SMI and provides a way for the application to generate the SMI.The driver creates the following sysfs entries for systems managementsoftware to perform these system management interrupts:

/sys/devices/platform/dcdbas/smi_data/sys/devices/platform/dcdbas/smi_data_buf_phys_addr/sys/devices/platform/dcdbas/smi_data_buf_size/sys/devices/platform/dcdbas/smi_request

Systems management software must perform the following steps to executea SMI using this driver:

  1. Lock smi_data.
  2. Write system management command to smi_data.
  3. Write “1” to smi_request to generate a calling interface SMI or“2” to generate a raw SMI.
  4. Read system management command response from smi_data.
  5. Unlock smi_data.

Host Control Action

Dell OpenManage supports a host control feature that allows the administratorto perform a power cycle or power off of the system after the OS has finishedshutting down. On some Dell systems, this host control feature requires thata driver perform a SMI after the OS has finished shutting down.

The driver creates the following sysfs entries for systems management softwareto schedule the driver to perform a power cycle or power off host controlaction after the system has finished shutting down:

/sys/devices/platform/dcdbas/host_control_action/sys/devices/platform/dcdbas/host_control_smi_type/sys/devices/platform/dcdbas/host_control_on_shutdown

Dell OpenManage performs the following steps to execute a power cycle orpower off host control action using this driver:

  1. Write host control action to be performed to host_control_action.
  2. Write type of SMI that driver needs to perform to host_control_smi_type.
  3. Write “1” to host_control_on_shutdown to enable host control action.
  4. Initiate OS shutdown.(Driver will perform host control SMI when it is notified that the OShas finished shutting down.)

Host Control SMI Type

The following table shows the value to write to host_control_smi_type toperform a power cycle or power off host control action:

PowerEdge SystemHost Control SMI Type
300HC_SMITYPE_TYPE1
1300HC_SMITYPE_TYPE1
1400HC_SMITYPE_TYPE2
500SCHC_SMITYPE_TYPE2
1500SCHC_SMITYPE_TYPE2
1550HC_SMITYPE_TYPE2
600SCHC_SMITYPE_TYPE2
1600SCHC_SMITYPE_TYPE2
650HC_SMITYPE_TYPE2
1655MCHC_SMITYPE_TYPE2
700HC_SMITYPE_TYPE3
750HC_SMITYPE_TYPE3