coreboot/Documentation/drivers/ipmi_kcs.md

IPMI KCS driver

The driver can be found in src/drivers/ipmi/. It works with BMC that provide a KCS I/O interface as specified in the IPMI standard.

The driver detects the IPMI version, reserves the I/O space in coreboot's resource allocator and writes the required ACPI and SMBIOS tables.

For developers

To use the driver, select the IPMI_KCS Kconfig and add the following PNP device under the LPC bridge device (in example for the KCS at 0xca2):

 chip drivers/ipmi
   device pnp ca2.0 on end         # IPMI KCS
 end

Note: The I/O base address needs to be aligned to 2.

The following registers can be set:

• have_nv_storage
  • Boolean
  • If true nv_storage_device_address will be added to SMBIOS type 38.
• nv_storage_device_address
  • Integer
  • The NV storage address as defined in SMBIOS spec for type 38.
• bmc_i2c_address
  • Integer
  • The i2c address of the BMC. zero if not applicable.
• have_apic
  • Boolean
  • If true the apic_interrupt will be added to SPMI table.
• apic_interrupt
  • Integer
  • The APIC interrupt used to notify about a change on the KCS.
• have_gpe
  • Boolean
  • If true the gpe_interrupt will be added to SPMI table.
• gpe_interrupt
  • Integer
  • The bit in GPE (SCI) used to notify about a change on the KCS.