ipmi: add Block Transfer interface support.

[ae]

Summary

Patched module is now able to detect and attach to BMC:

ipmi0: <IPMI System Interface> on isa0
ipmi0: BT mode found at io 0xe4 alignment 0x1 on isa
ipmi0: IPMI device rev. 1, firmware rev. 6.48, version 2.0, device support mask 0xaf
ipmi0: Number of channels 0
ipmi0: Attached watchdog
ipmi0: Establishing power cycle handler

ipmitools also works:

# ipmitool channel info
Channel 0xf info:
  Channel Medium Type   : System Interface
  Channel Protocol Type : BT-15
  Session Support       : session-less
  Active Session Count  : 0
  Protocol Vendor ID    : 7154

dmidecode:

Handle 0x0037, DMI type 38, 18 bytes
IPMI Device Information
        Interface Type: BT (Block Transfer)
        Specification Version: 2.0
        I2C Slave Address: 0x10
        NV Storage Device: Not Present
        Base Address: 0x00000000000000E4 (I/O)
        Register Spacing: Successive Byte Boundaries

[imp]

This looks generally good.
I think I have an arm server with bt mode. Any chance it will work?

[ambrisko]

Thanks for adding BT.

[ae]

In D40421#920356, @imp wrote:

This looks generally good.
I think I have an arm server with bt mode. Any chance it will work?

I hope this should work. It would be nice if you try test it.