blob: 81202e26f899570eb451c14b24a20c6bcb792bf9 [file] [log] [blame] [edit]
/*
* Copyright 2020 The Hafnium Authors.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* https://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#include "hf/fdt_patch.h"
#include <libfdt.h>
#include "hf/boot_params.h"
#include "hf/dlog.h"
#include "hf/fdt.h"
#include "hf/fdt_handler.h"
#include "hf/layout.h"
#include "hf/mm.h"
static bool patch_uint(void *fdt, int off, const char *prop, uint64_t val)
{
const void *data;
int lenp;
data = fdt_getprop(fdt, off, prop, &lenp);
if (data == NULL) {
return false;
}
switch (lenp) {
case sizeof(uint64_t): {
return fdt_setprop_inplace_u64(fdt, off, prop, val) == 0;
}
case sizeof(uint32_t): {
return (val <= UINT32_MAX) &&
(fdt_setprop_inplace_u32(fdt, off, prop, val) == 0);
}
default: {
return false;
}
}
}
static bool add_mem_reservation(void *fdt, paddr_t begin, paddr_t end)
{
size_t len = pa_difference(begin, end);
return fdt_add_mem_rsv(fdt, pa_addr(begin), len) == 0;
}
bool fdt_patch(struct mm_stage1_locked stage1_locked, paddr_t fdt_addr,
struct boot_params_update *p, struct mpool *ppool)
{
void *fdt;
size_t buf_size;
int off;
bool ret = false;
bool rsv;
size_t i;
/* Map the fdt header in. */
fdt = mm_identity_map(stage1_locked, fdt_addr,
pa_add(fdt_addr, FDT_V17_HEADER_SIZE), MM_MODE_R,
ppool);
if (!fdt) {
dlog_error("Unable to map FDT header.\n");
return false;
}
if (fdt_check_header(fdt) != 0) {
dlog_error("FDT failed header validation.\n");
goto err_unmap_fdt_header;
}
/* Map the fdt (+ a page) in r/w mode in preparation for updating it. */
buf_size = fdt_totalsize(fdt) + PAGE_SIZE;
fdt = mm_identity_map(stage1_locked, fdt_addr,
pa_add(fdt_addr, buf_size), MM_MODE_R | MM_MODE_W,
ppool);
if (!fdt) {
dlog_error("Unable to map FDT in r/w mode.\n");
goto err_unmap_fdt_header;
}
if (fdt_check_full(fdt, buf_size) != 0) {
dlog_error("FDT failed validation.\n");
goto out_unmap_fdt;
}
/* Allow some extra room for the modifications to the FDT. */
if (fdt_open_into(fdt, fdt, buf_size) != 0) {
dlog_error("FDT failed to open_into.\n");
goto out_unmap_fdt;
}
off = fdt_path_offset(fdt, "/chosen");
if (off < 0) {
dlog_error("Unable to find FDT '/chosen' node.\n");
goto out_unmap_fdt;
}
/* Patch FDT to point to new ramdisk. */
if (!patch_uint(fdt, off, FDT_PROP_INITRD_START,
pa_addr(p->initrd_begin))) {
dlog_error("Unable to write" FDT_PROP_INITRD_START "\n");
goto out_unmap_fdt;
}
if (!patch_uint(fdt, off, FDT_PROP_INITRD_END,
pa_addr(p->initrd_end))) {
dlog_error("Unable to write " FDT_PROP_INITRD_END "\n");
goto out_unmap_fdt;
}
/*
* Patch FDT to reserve hypervisor memory so the primary VM doesn't try
* to use it.
*/
rsv = true;
rsv &= add_mem_reservation(fdt, layout_text_begin(), layout_text_end());
rsv &= add_mem_reservation(fdt, layout_rodata_begin(),
layout_rodata_end());
rsv &= add_mem_reservation(fdt, layout_data_begin(), layout_data_end());
/* Patch FDT to reserve memory for secondary VMs. */
for (i = 0; i < p->reserved_ranges_count; ++i) {
struct mem_range range = p->reserved_ranges[i];
rsv &= add_mem_reservation(fdt, range.begin, range.end);
}
if (!rsv) {
dlog_error("Unable to add memory reservations to FDT.\n");
goto out_unmap_fdt;
}
if (fdt_pack(fdt) != 0) {
dlog_error("Failed to pack FDT.\n");
goto out_unmap_fdt;
}
ret = true;
out_unmap_fdt:
/* Unmap FDT. */
if (!mm_unmap(stage1_locked, fdt_addr,
pa_add(fdt_addr, fdt_totalsize(fdt) + PAGE_SIZE),
ppool)) {
dlog_error("Unable to unmap writable FDT.\n");
return false;
}
return ret;
err_unmap_fdt_header:
mm_unmap(stage1_locked, fdt_addr, pa_add(fdt_addr, FDT_V17_HEADER_SIZE),
ppool);
return false;
}