historical/m0-applesillicon.git/xnu-qemu-arm64-5.1.0/roms/edk2/ArmVirtPkg/PrePi/FdtParser.c
2024-01-16 11:20:27 -06:00

84 lines
1.8 KiB
C

/*
* Copyright (c) 2015, Linaro Ltd. All rights reserved.
*
* SPDX-License-Identifier: BSD-2-Clause-Patent
*/
#include <Uefi.h>
#include <Include/libfdt.h>
BOOLEAN
FindMemnode (
IN VOID *DeviceTreeBlob,
OUT UINT64 *SystemMemoryBase,
OUT UINT64 *SystemMemorySize
)
{
INT32 MemoryNode;
INT32 AddressCells;
INT32 SizeCells;
INT32 Length;
CONST INT32 *Prop;
if (fdt_check_header (DeviceTreeBlob) != 0) {
return FALSE;
}
//
// Look for a node called "memory" at the lowest level of the tree
//
MemoryNode = fdt_path_offset (DeviceTreeBlob, "/memory");
if (MemoryNode <= 0) {
return FALSE;
}
//
// Retrieve the #address-cells and #size-cells properties
// from the root node, or use the default if not provided.
//
AddressCells = 1;
SizeCells = 1;
Prop = fdt_getprop (DeviceTreeBlob, 0, "#address-cells", &Length);
if (Length == 4) {
AddressCells = fdt32_to_cpu (*Prop);
}
Prop = fdt_getprop (DeviceTreeBlob, 0, "#size-cells", &Length);
if (Length == 4) {
SizeCells = fdt32_to_cpu (*Prop);
}
//
// Now find the 'reg' property of the /memory node, and read the first
// range listed.
//
Prop = fdt_getprop (DeviceTreeBlob, MemoryNode, "reg", &Length);
if (Length < (AddressCells + SizeCells) * sizeof (INT32)) {
return FALSE;
}
*SystemMemoryBase = fdt32_to_cpu (Prop[0]);
if (AddressCells > 1) {
*SystemMemoryBase = (*SystemMemoryBase << 32) | fdt32_to_cpu (Prop[1]);
}
Prop += AddressCells;
*SystemMemorySize = fdt32_to_cpu (Prop[0]);
if (SizeCells > 1) {
*SystemMemorySize = (*SystemMemorySize << 32) | fdt32_to_cpu (Prop[1]);
}
return TRUE;
}
VOID
CopyFdt (
IN VOID *FdtDest,
IN VOID *FdtSource
)
{
fdt_pack(FdtSource);
CopyMem (FdtDest, FdtSource, fdt_totalsize (FdtSource));
}