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+# 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.
+
+
+[IPMI]: https://www.intel.com/content/dam/www/public/us/en/documents/product-briefs/ipmi-second-gen-interface-spec-v2-rev1-1.pdf