misc: Add ASPEED KCS driver for MCTP purposes

IBM have developed a vendor-defined MCTP binding that utilises LPC IO and FW interfaces to exchange MCTP messages. A KCS device in the IO space is used to send single-byte control messages initialising the MCTP channel and exchanging ownership of data buffers. This driver exposes the KCS message stream to userspace, allowing an MCTP-capable application to manipulate the data exposed via the FW space. OpenBMC-Staging-Count: 1 Signed-off-by: Andrew Jeffery <andrew@aj.id.au> Signed-off-by: Joel Stanley <joel@jms.id.au>
openbmc · Mar 30, 2020 · 9a3b539 · 9a3b539
1 parent d966e74
commit 9a3b539
Show file tree

Hide file tree

Showing 3 changed files with 451 additions and 0 deletions.
diff --git a/drivers/misc/Kconfig b/drivers/misc/Kconfig
@@ -454,6 +454,13 @@ config XILINX_SDFEC
 
 	  If unsure, say N.
 
+config MCTP_LPC
+	tristate "MCTP LPC binding implementation for ASPEED BMCs"
+	depends on REGMAP
+	help
+	  Implements the MCTP LPC binding via KCS LPC IO cycles for control and
+          LPC FWH cycles for data
+
 config MISC_RTSX
 	tristate
 	default MISC_RTSX_PCI || MISC_RTSX_USB

diff --git a/drivers/misc/Makefile b/drivers/misc/Makefile
@@ -59,3 +59,4 @@ obj-$(CONFIG_HABANA_AI)		+= habanalabs/
 obj-$(CONFIG_XILINX_SDFEC)	+= xilinx_sdfec.o
 obj-$(CONFIG_NPCM7XX_LPC_BPC)	+= npcm7xx-lpc-bpc.o
 obj-$(CONFIG_NPCM7XX_PCI_MBOX)	+= npcm7xx-pci-mbox.o
+obj-$(CONFIG_MCTP_LPC)		+= mctp-lpc.o