cmd: add tlv_eeprom command

Add support for read/write of ONIE "Tlvinfo" EEPROM data format. TLV
stands for Type-Length-Value. The data format is described here:

  https://opencomputeproject.github.io/onie/design-spec/hw_requirements.html#board-eeprom-information-format

Based on U-Boot patch from the Open Compute project:

  ec87e872d4/patches/u-boot/common/feature-sys-eeprom-tlv-common.patch

Keep only I2C EEPROM support. Use the generic eeprom driver. Fix
checkpatch issues.

Add support for multiple EEPROM TLV stores on the same system. This is
useful in case of SOM and carrier that both provide ID and hardware
configuration information.

Add option to enable for SPL. This allows selection of RAM configuration
based on EEPROM stored board identification.

Signed-off-by: Baruch Siach <baruch@tkos.co.il>

cmd/Kconfig

@@ -242,6 +242,20 @@ config CMD_REGINFO
 	help
 	  Register dump
 
+config CMD_TLV_EEPROM
+	bool "tlv_eeprom"
+	depends on I2C_EEPROM
+	help
+	  Display and program the system EEPROM data block in ONIE Tlvinfo
+	  format. TLV stands for Type-Length-Value.
+
+config SPL_CMD_TLV_EEPROM
+	bool "tlv_eeprom for SPL"
+	depends on SPL_I2C_EEPROM
+	select SPL_DRIVERS_MISC_SUPPORT
+	help
+	  Read system EEPROM data block in ONIE Tlvinfo format from SPL.
+
 endmenu
 
 menu "Boot commands"

cmd/Makefile

@@ -183,6 +183,8 @@ obj-$(CONFIG_X86) += x86/
 obj-$(CONFIG_ARCH_MVEBU) += mvebu/
 endif # !CONFIG_SPL_BUILD
 
+obj-$(CONFIG_$(SPL_)CMD_TLV_EEPROM) += tlv_eeprom.o
+
 # core command
 obj-y += nvedit.o