1 files changed, 73 insertions, 0 deletions
diff --git a/drivers/platform/x86/intel/ifs/core.c b/drivers/platform/x86/intel/ifs/core.c
new file mode 100644
index 000000000000..27204e3d674d
--- /dev/null
+++ b/drivers/platform/x86/intel/ifs/core.c
@@ -0,0 +1,73 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/* Copyright(c) 2022 Intel Corporation. */
+
+#include <linux/module.h>
+#include <linux/kdev_t.h>
+#include <linux/semaphore.h>
+
+#include <asm/cpu_device_id.h>
+
+#include "ifs.h"
+
+#define X86_MATCH(model)				\
+	X86_MATCH_VENDOR_FAM_MODEL_FEATURE(INTEL, 6,	\
+		INTEL_FAM6_##model, X86_FEATURE_CORE_CAPABILITIES, NULL)
+
+static const struct x86_cpu_id ifs_cpu_ids[] __initconst = {
+	X86_MATCH(SAPPHIRERAPIDS_X),
+	{}
+};
+MODULE_DEVICE_TABLE(x86cpu, ifs_cpu_ids);
+
+static struct ifs_device ifs_device = {
+	.data = {
+		.integrity_cap_bit = MSR_INTEGRITY_CAPS_PERIODIC_BIST_BIT,
+	},
+	.misc = {
+		.name = "intel_ifs_0",
+		.nodename = "intel_ifs/0",
+		.minor = MISC_DYNAMIC_MINOR,
+	},
+};
+
+static int __init ifs_init(void)
+{
+	const struct x86_cpu_id *m;
+	u64 msrval;
+
+	m = x86_match_cpu(ifs_cpu_ids);
+	if (!m)
+		return -ENODEV;
+
+	if (rdmsrl_safe(MSR_IA32_CORE_CAPS, &msrval))
+		return -ENODEV;
+
+	if (!(msrval & MSR_IA32_CORE_CAPS_INTEGRITY_CAPS))
+		return -ENODEV;
+
+	if (rdmsrl_safe(MSR_INTEGRITY_CAPS, &msrval))
+		return -ENODEV;
+
+	ifs_device.misc.groups = ifs_get_groups();
+
+	if ((msrval & BIT(ifs_device.data.integrity_cap_bit)) &&
+	    !misc_register(&ifs_device.misc)) {
+		down(&ifs_sem);
+		ifs_load_firmware(ifs_device.misc.this_device);
+		up(&ifs_sem);
+		return 0;
+	}
+
+	return -ENODEV;
+}
+
+static void __exit ifs_exit(void)
+{
+	misc_deregister(&ifs_device.misc);
+}
+
+module_init(ifs_init);
+module_exit(ifs_exit);
+
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("Intel In Field Scan (IFS) device");