127 lines
2.9 KiB
C
127 lines
2.9 KiB
C
// SPDX-License-Identifier: GPL-2.0-only
|
|
|
|
#define pr_fmt(fmt) "efi: " fmt
|
|
|
|
#include <linux/module.h>
|
|
#include <linux/init.h>
|
|
#include <linux/efi.h>
|
|
#include <linux/libfdt.h>
|
|
#include <linux/of_fdt.h>
|
|
|
|
#include <asm/unaligned.h>
|
|
|
|
enum {
|
|
SYSTAB,
|
|
MMBASE,
|
|
MMSIZE,
|
|
DCSIZE,
|
|
DCVERS,
|
|
|
|
PARAMCOUNT
|
|
};
|
|
|
|
static __initconst const char name[][22] = {
|
|
[SYSTAB] = "System Table ",
|
|
[MMBASE] = "MemMap Address ",
|
|
[MMSIZE] = "MemMap Size ",
|
|
[DCSIZE] = "MemMap Desc. Size ",
|
|
[DCVERS] = "MemMap Desc. Version ",
|
|
};
|
|
|
|
static __initconst const struct {
|
|
const char path[17];
|
|
const char params[PARAMCOUNT][26];
|
|
} dt_params[] = {
|
|
{
|
|
#ifdef CONFIG_XEN // <-------17------>
|
|
.path = "/hypervisor/uefi",
|
|
.params = {
|
|
[SYSTAB] = "xen,uefi-system-table",
|
|
[MMBASE] = "xen,uefi-mmap-start",
|
|
[MMSIZE] = "xen,uefi-mmap-size",
|
|
[DCSIZE] = "xen,uefi-mmap-desc-size",
|
|
[DCVERS] = "xen,uefi-mmap-desc-ver",
|
|
}
|
|
}, {
|
|
#endif
|
|
.path = "/chosen",
|
|
.params = { // <-----------26----------->
|
|
[SYSTAB] = "linux,uefi-system-table",
|
|
[MMBASE] = "linux,uefi-mmap-start",
|
|
[MMSIZE] = "linux,uefi-mmap-size",
|
|
[DCSIZE] = "linux,uefi-mmap-desc-size",
|
|
[DCVERS] = "linux,uefi-mmap-desc-ver",
|
|
}
|
|
}
|
|
};
|
|
|
|
static int __init efi_get_fdt_prop(const void *fdt, int node, const char *pname,
|
|
const char *rname, void *var, int size)
|
|
{
|
|
const void *prop;
|
|
int len;
|
|
u64 val;
|
|
|
|
prop = fdt_getprop(fdt, node, pname, &len);
|
|
if (!prop)
|
|
return 1;
|
|
|
|
val = (len == 4) ? (u64)be32_to_cpup(prop) : get_unaligned_be64(prop);
|
|
|
|
if (size == 8)
|
|
*(u64 *)var = val;
|
|
else
|
|
*(u32 *)var = (val < U32_MAX) ? val : U32_MAX; // saturate
|
|
|
|
if (efi_enabled(EFI_DBG))
|
|
pr_info(" %s: 0x%0*llx\n", rname, size * 2, val);
|
|
|
|
return 0;
|
|
}
|
|
|
|
u64 __init efi_get_fdt_params(struct efi_memory_map_data *mm)
|
|
{
|
|
const void *fdt = initial_boot_params;
|
|
unsigned long systab;
|
|
int i, j, node;
|
|
struct {
|
|
void *var;
|
|
int size;
|
|
} target[] = {
|
|
[SYSTAB] = { &systab, sizeof(systab) },
|
|
[MMBASE] = { &mm->phys_map, sizeof(mm->phys_map) },
|
|
[MMSIZE] = { &mm->size, sizeof(mm->size) },
|
|
[DCSIZE] = { &mm->desc_size, sizeof(mm->desc_size) },
|
|
[DCVERS] = { &mm->desc_version, sizeof(mm->desc_version) },
|
|
};
|
|
|
|
BUILD_BUG_ON(ARRAY_SIZE(target) != ARRAY_SIZE(name));
|
|
BUILD_BUG_ON(ARRAY_SIZE(target) != ARRAY_SIZE(dt_params[0].params));
|
|
|
|
for (i = 0; i < ARRAY_SIZE(dt_params); i++) {
|
|
node = fdt_path_offset(fdt, dt_params[i].path);
|
|
if (node < 0)
|
|
continue;
|
|
|
|
if (efi_enabled(EFI_DBG))
|
|
pr_info("Getting UEFI parameters from %s in DT:\n",
|
|
dt_params[i].path);
|
|
|
|
for (j = 0; j < ARRAY_SIZE(target); j++) {
|
|
const char *pname = dt_params[i].params[j];
|
|
|
|
if (!efi_get_fdt_prop(fdt, node, pname, name[j],
|
|
target[j].var, target[j].size))
|
|
continue;
|
|
if (!j)
|
|
goto notfound;
|
|
pr_err("Can't find property '%s' in DT!\n", pname);
|
|
return 0;
|
|
}
|
|
return systab;
|
|
}
|
|
notfound:
|
|
pr_info("UEFI not found.\n");
|
|
return 0;
|
|
}
|