1 files changed, 25 insertions, 0 deletions
diff --git a/arch/x86/kernel/eisa.c b/arch/x86/kernel/eisa.c
new file mode 100644
index 000000000000..9535a6507db7
--- /dev/null
+++ b/arch/x86/kernel/eisa.c
@@ -0,0 +1,25 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * EISA specific code
+ */
+#include <linux/cc_platform.h>
+#include <linux/ioport.h>
+#include <linux/eisa.h>
+#include <linux/io.h>
+
+#include <xen/xen.h>
+
+static __init int eisa_bus_probe(void)
+{
+	u32 *p;
+
+	if ((xen_pv_domain() && !xen_initial_domain()) || cc_platform_has(CC_ATTR_GUEST_SEV_SNP))
+		return 0;
+
+	p = memremap(0x0FFFD9, 4, MEMREMAP_WB);
+	if (p && *p == 'E' + ('I' << 8) + ('S' << 16) + ('A' << 24))
+		EISA_bus = 1;
+	memunmap(p);
+	return 0;
+}
+subsys_initcall(eisa_bus_probe);