x86: Add a cpuid command
It is useful to obtain the results of cpuid queries, so add a command
for this.
Signed-off-by: Simon Glass <sjg@chromium.org>
diff --git a/cmd/x86/Makefile b/cmd/x86/Makefile
index b1f39d3..1648907 100644
--- a/cmd/x86/Makefile
+++ b/cmd/x86/Makefile
@@ -1,7 +1,7 @@
# SPDX-License-Identifier: GPL-2.0+
obj-$(CONFIG_CMD_CBSYSINFO) += cbsysinfo.o
-obj-y += mtrr.o
+obj-y += cpuid.o mtrr.o
obj-$(CONFIG_CMD_EXCEPTION) += exception.o
obj-$(CONFIG_USE_HOB) += hob.o
obj-$(CONFIG_HAVE_FSP) += fsp.o
diff --git a/cmd/x86/cpuid.c b/cmd/x86/cpuid.c
new file mode 100644
index 0000000..222754b
--- /dev/null
+++ b/cmd/x86/cpuid.c
@@ -0,0 +1,37 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * The 'cpuid' command provides access to the CPU's cpuid information
+ *
+ * Copyright 2024 Google, LLC
+ * Written by Simon Glass <sjg@chromium.org>
+ */
+
+#include <command.h>
+#include <vsprintf.h>
+#include <asm/cpu.h>
+
+static int do_cpuid(struct cmd_tbl *cmdtp, int flag, int argc,
+ char *const argv[])
+{
+ struct cpuid_result res;
+ ulong op;
+
+ if (argc < 2)
+ return CMD_RET_USAGE;
+
+ op = hextoul(argv[1], NULL);
+ res = cpuid(op);
+ printf("eax %08x\n", res.eax);
+ printf("ebx %08x\n", res.ebx);
+ printf("ecx %08x\n", res.ecx);
+ printf("edx %08x\n", res.edx);
+
+ return 0;
+}
+
+U_BOOT_LONGHELP(cpuid, "Show CPU Identification information");
+
+U_BOOT_CMD(
+ cpuid, 2, 1, do_cpuid,
+ "cpuid <op>", cpuid_help_text
+);