1*4882a593Smuzhiyun // SPDX-License-Identifier: GPL-2.0
2*4882a593Smuzhiyun /* Copyright(c) 2019 Intel Corporation. All rights reserved. */
3*4882a593Smuzhiyun #include <linux/efi.h>
4*4882a593Smuzhiyun #include <asm/e820/api.h>
5*4882a593Smuzhiyun #include "fake_mem.h"
6*4882a593Smuzhiyun
efi_fake_memmap_early(void)7*4882a593Smuzhiyun void __init efi_fake_memmap_early(void)
8*4882a593Smuzhiyun {
9*4882a593Smuzhiyun int i;
10*4882a593Smuzhiyun
11*4882a593Smuzhiyun /*
12*4882a593Smuzhiyun * The late efi_fake_mem() call can handle all requests if
13*4882a593Smuzhiyun * EFI_MEMORY_SP support is disabled.
14*4882a593Smuzhiyun */
15*4882a593Smuzhiyun if (!efi_soft_reserve_enabled())
16*4882a593Smuzhiyun return;
17*4882a593Smuzhiyun
18*4882a593Smuzhiyun if (!efi_enabled(EFI_MEMMAP) || !nr_fake_mem)
19*4882a593Smuzhiyun return;
20*4882a593Smuzhiyun
21*4882a593Smuzhiyun /*
22*4882a593Smuzhiyun * Given that efi_fake_memmap() needs to perform memblock
23*4882a593Smuzhiyun * allocations it needs to run after e820__memblock_setup().
24*4882a593Smuzhiyun * However, if efi_fake_mem specifies EFI_MEMORY_SP for a given
25*4882a593Smuzhiyun * address range that potentially needs to mark the memory as
26*4882a593Smuzhiyun * reserved prior to e820__memblock_setup(). Update e820
27*4882a593Smuzhiyun * directly if EFI_MEMORY_SP is specified for an
28*4882a593Smuzhiyun * EFI_CONVENTIONAL_MEMORY descriptor.
29*4882a593Smuzhiyun */
30*4882a593Smuzhiyun for (i = 0; i < nr_fake_mem; i++) {
31*4882a593Smuzhiyun struct efi_mem_range *mem = &efi_fake_mems[i];
32*4882a593Smuzhiyun efi_memory_desc_t *md;
33*4882a593Smuzhiyun u64 m_start, m_end;
34*4882a593Smuzhiyun
35*4882a593Smuzhiyun if ((mem->attribute & EFI_MEMORY_SP) == 0)
36*4882a593Smuzhiyun continue;
37*4882a593Smuzhiyun
38*4882a593Smuzhiyun m_start = mem->range.start;
39*4882a593Smuzhiyun m_end = mem->range.end;
40*4882a593Smuzhiyun for_each_efi_memory_desc(md) {
41*4882a593Smuzhiyun u64 start, end, size;
42*4882a593Smuzhiyun
43*4882a593Smuzhiyun if (md->type != EFI_CONVENTIONAL_MEMORY)
44*4882a593Smuzhiyun continue;
45*4882a593Smuzhiyun
46*4882a593Smuzhiyun start = md->phys_addr;
47*4882a593Smuzhiyun end = md->phys_addr + (md->num_pages << EFI_PAGE_SHIFT) - 1;
48*4882a593Smuzhiyun
49*4882a593Smuzhiyun if (m_start <= end && m_end >= start)
50*4882a593Smuzhiyun /* fake range overlaps descriptor */;
51*4882a593Smuzhiyun else
52*4882a593Smuzhiyun continue;
53*4882a593Smuzhiyun
54*4882a593Smuzhiyun /*
55*4882a593Smuzhiyun * Trim the boundary of the e820 update to the
56*4882a593Smuzhiyun * descriptor in case the fake range overlaps
57*4882a593Smuzhiyun * !EFI_CONVENTIONAL_MEMORY
58*4882a593Smuzhiyun */
59*4882a593Smuzhiyun start = max(start, m_start);
60*4882a593Smuzhiyun end = min(end, m_end);
61*4882a593Smuzhiyun size = end - start + 1;
62*4882a593Smuzhiyun
63*4882a593Smuzhiyun if (end <= start)
64*4882a593Smuzhiyun continue;
65*4882a593Smuzhiyun
66*4882a593Smuzhiyun /*
67*4882a593Smuzhiyun * Ensure each efi_fake_mem instance results in
68*4882a593Smuzhiyun * a unique e820 resource
69*4882a593Smuzhiyun */
70*4882a593Smuzhiyun e820__range_remove(start, size, E820_TYPE_RAM, 1);
71*4882a593Smuzhiyun e820__range_add(start, size, E820_TYPE_SOFT_RESERVED);
72*4882a593Smuzhiyun e820__update_table(e820_table);
73*4882a593Smuzhiyun }
74*4882a593Smuzhiyun }
75*4882a593Smuzhiyun }
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