1===================================
2Dell Systems Management Base Driver
3===================================
4
5Overview
6========
7
8The Dell Systems Management Base Driver provides a sysfs interface for
9systems management software such as Dell OpenManage to perform system
10management interrupts and host control actions (system power cycle or
11power off after OS shutdown) on certain Dell systems.
12
13Dell OpenManage requires this driver on the following Dell PowerEdge systems:
14300, 1300, 1400, 400SC, 500SC, 1500SC, 1550, 600SC, 1600SC, 650, 1655MC,
15700, and 750.  Other Dell software such as the open source libsmbios project
16is expected to make use of this driver, and it may include the use of this
17driver on other Dell systems.
18
19The Dell libsmbios project aims towards providing access to as much BIOS
20information as possible.  See http://linux.dell.com/libsmbios/main/ for
21more information about the libsmbios project.
22
23
24System Management Interrupt
25===========================
26
27On some Dell systems, systems management software must access certain
28management information via a system management interrupt (SMI).  The SMI data
29buffer must reside in 32-bit address space, and the physical address of the
30buffer is required for the SMI.  The driver maintains the memory required for
31the SMI and provides a way for the application to generate the SMI.
32The driver creates the following sysfs entries for systems management
33software to perform these system management interrupts::
34
35	/sys/devices/platform/dcdbas/smi_data
36	/sys/devices/platform/dcdbas/smi_data_buf_phys_addr
37	/sys/devices/platform/dcdbas/smi_data_buf_size
38	/sys/devices/platform/dcdbas/smi_request
39
40Systems management software must perform the following steps to execute
41a SMI using this driver:
42
431) Lock smi_data.
442) Write system management command to smi_data.
453) Write "1" to smi_request to generate a calling interface SMI or
46   "2" to generate a raw SMI.
474) Read system management command response from smi_data.
485) Unlock smi_data.
49
50
51Host Control Action
52===================
53
54Dell OpenManage supports a host control feature that allows the administrator
55to perform a power cycle or power off of the system after the OS has finished
56shutting down.  On some Dell systems, this host control feature requires that
57a driver perform a SMI after the OS has finished shutting down.
58
59The driver creates the following sysfs entries for systems management software
60to schedule the driver to perform a power cycle or power off host control
61action after the system has finished shutting down:
62
63/sys/devices/platform/dcdbas/host_control_action
64/sys/devices/platform/dcdbas/host_control_smi_type
65/sys/devices/platform/dcdbas/host_control_on_shutdown
66
67Dell OpenManage performs the following steps to execute a power cycle or
68power off host control action using this driver:
69
701) Write host control action to be performed to host_control_action.
712) Write type of SMI that driver needs to perform to host_control_smi_type.
723) Write "1" to host_control_on_shutdown to enable host control action.
734) Initiate OS shutdown.
74   (Driver will perform host control SMI when it is notified that the OS
75   has finished shutting down.)
76
77
78Host Control SMI Type
79=====================
80
81The following table shows the value to write to host_control_smi_type to
82perform a power cycle or power off host control action:
83
84=================== =====================
85PowerEdge System    Host Control SMI Type
86=================== =====================
87      300             HC_SMITYPE_TYPE1
88     1300             HC_SMITYPE_TYPE1
89     1400             HC_SMITYPE_TYPE2
90      500SC           HC_SMITYPE_TYPE2
91     1500SC           HC_SMITYPE_TYPE2
92     1550             HC_SMITYPE_TYPE2
93      600SC           HC_SMITYPE_TYPE2
94     1600SC           HC_SMITYPE_TYPE2
95      650             HC_SMITYPE_TYPE2
96     1655MC           HC_SMITYPE_TYPE2
97      700             HC_SMITYPE_TYPE3
98      750             HC_SMITYPE_TYPE3
99=================== =====================
100