x86: Add a simple command to show FSP HOB information

FSP builds a series of data structures called the Hand-Off-Blocks
(HOBs) as it progresses through initializing the silicon. These data
structures conform to the HOB format as described in the Platform
Initialization (PI) specification Volume 3 Shared Architectual
Elements specification, which is part of the UEFI specification.

Create a simple command to parse the HOB list to display the HOB
address, type and length in bytes.

Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
Acked-by: Simon Glass <sjg@chromium.org>

arch/x86/lib/Makefile

@@ -10,6 +10,7 @@ obj-y += bios_asm.o
 obj-y += bios_interrupts.o
 obj-$(CONFIG_CMD_BOOTM) += bootm.o
 obj-y	+= cmd_boot.o
+obj-$(CONFIG_HAVE_FSP) += cmd_hob.o
 obj-y	+= gcc.o
 obj-y	+= init_helpers.o
 obj-y	+= interrupts.o

arch/x86/lib/cmd_hob.c

@@ -0,0 +1,67 @@
+/*
+ * Copyright (C) 2014, Bin Meng <bmeng.cn@gmail.com>
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+#include <common.h>
+#include <command.h>
+#include <linux/compiler.h>
+#include <asm/arch/fsp/fsp_support.h>
+
+DECLARE_GLOBAL_DATA_PTR;
+
+static char *hob_type[] = {
+	"reserved",
+	"Hand-off",
+	"Memory Allocation",
+	"Resource Descriptor",
+	"GUID Extension",
+	"Firmware Volumn",
+	"CPU",
+	"Memory Pool",
+	"reserved",
+	"Firmware Volumn 2",
+	"Load PEIM Unused",
+	"UEFI Capsule",
+};
+
+int do_hob(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
+{
+	union hob_pointers_t hob;
+	u16 type;
+	char *desc;
+	int i = 0;
+
+	hob.raw = (u8 *)gd->arch.hob_list;
+
+	printf("HOB list address: 0x%08x\n\n", (unsigned int)hob.raw);
+
+	printf("No. | Address  | Type                | Length in Bytes\n");
+	printf("----|----------|---------------------|----------------\n");
+	while (!END_OF_HOB(hob)) {
+		printf("%-3d | %08x | ", i, (unsigned int)hob.raw);
+		type = hob.hdr->type;
+		if (type == HOB_TYPE_UNUSED)
+			desc = "*Unused*";
+		else if (type == HOB_TYPE_EOH)
+			desc = "**END OF HOB**";
+		else if (type >= 0 && type <= ARRAY_SIZE(hob_type))
+			desc = hob_type[type];
+		else
+			desc = "!!!Invalid Type!!!";
+		printf("%-19s | %-15d\n", desc, hob.hdr->len);
+		hob.raw = GET_NEXT_HOB(hob);
+		i++;
+	}
+
+	return 0;
+}
+
+/* -------------------------------------------------------------------- */
+
+U_BOOT_CMD(
+	hob,	1,	1,	do_hob,
+	"print FSP Hand-Off Block information",
+	""
+);