xref: /openbmc/linux/arch/x86/kernel/pmem.c (revision 1dd0dd0b)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Copyright (c) 2015, Christoph Hellwig.
4  * Copyright (c) 2015, Intel Corporation.
5  */
6 #include <linux/platform_device.h>
7 #include <linux/init.h>
8 #include <linux/ioport.h>
9 
10 static int found(struct resource *res, void *data)
11 {
12 	return 1;
13 }
14 
15 static __init int register_e820_pmem(void)
16 {
17 	struct platform_device *pdev;
18 	int rc;
19 
20 	rc = walk_iomem_res_desc(IORES_DESC_PERSISTENT_MEMORY_LEGACY,
21 				 IORESOURCE_MEM, 0, -1, NULL, found);
22 	if (rc <= 0)
23 		return 0;
24 
25 	/*
26 	 * See drivers/nvdimm/e820.c for the implementation, this is
27 	 * simply here to trigger the module to load on demand.
28 	 */
29 	pdev = platform_device_alloc("e820_pmem", -1);
30 
31 	rc = platform_device_add(pdev);
32 	if (rc)
33 		platform_device_put(pdev);
34 
35 	return rc;
36 }
37 device_initcall(register_e820_pmem);
38