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-rw-r--r--src/lib/selfboot.c543
1 files changed, 543 insertions, 0 deletions
diff --git a/src/lib/selfboot.c b/src/lib/selfboot.c
new file mode 100644
index 0000000000..2556a14d6e
--- /dev/null
+++ b/src/lib/selfboot.c
@@ -0,0 +1,543 @@
+/*
+ * This file is part of the coreboot project.
+ *
+ * Copyright (C) 2003 Eric W. Biederman <ebiederm@xmission.com>
+ * Copyright (C) 2009 Ron Minnich <rminnich@gmail.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 2 of the License.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA, 02110-1301 USA
+ */
+
+#include <arch/byteorder.h>
+#include <console/console.h>
+#include <fallback.h>
+#include <boot/elf.h>
+#include <boot/elf_boot.h>
+#include <boot/coreboot_tables.h>
+#include <stdint.h>
+#include <stdlib.h>
+#include <string.h>
+#include <cbfs.h>
+#include <lib.h>
+#if CONFIG_COLLECT_TIMESTAMPS
+#include <timestamp.h>
+#endif
+
+/* Maximum physical address we can use for the coreboot bounce buffer. */
+#ifndef MAX_ADDR
+#define MAX_ADDR -1UL
+#endif
+
+/* from coreboot_ram.ld: */
+extern unsigned char _ram_seg;
+extern unsigned char _eram_seg;
+
+static const unsigned long lb_start = (unsigned long)&_ram_seg;
+static const unsigned long lb_end = (unsigned long)&_eram_seg;
+
+struct segment {
+ struct segment *next;
+ struct segment *prev;
+ unsigned long s_dstaddr;
+ unsigned long s_srcaddr;
+ unsigned long s_memsz;
+ unsigned long s_filesz;
+ int compression;
+};
+
+/* The problem:
+ * Static executables all want to share the same addresses
+ * in memory because only a few addresses are reliably present on
+ * a machine, and implementing general relocation is hard.
+ *
+ * The solution:
+ * - Allocate a buffer the size of the coreboot image plus additional
+ * required space.
+ * - Anything that would overwrite coreboot copy into the lower part of
+ * the buffer.
+ * - After loading an ELF image copy coreboot to the top of the buffer.
+ * - Then jump to the loaded image.
+ *
+ * Benefits:
+ * - Nearly arbitrary standalone executables can be loaded.
+ * - Coreboot is preserved, so it can be returned to.
+ * - The implementation is still relatively simple,
+ * and much simpler than the general case implemented in kexec.
+ */
+
+static unsigned long bounce_size, bounce_buffer;
+
+static void get_bounce_buffer(struct lb_memory *mem, unsigned long req_size)
+{
+ unsigned long lb_size;
+ unsigned long mem_entries;
+ unsigned long buffer;
+ int i;
+ lb_size = lb_end - lb_start;
+ /* Plus coreboot size so I have somewhere
+ * to place a copy to return to.
+ */
+ lb_size = req_size + lb_size;
+ mem_entries = (mem->size - sizeof(*mem)) / sizeof(mem->map[0]);
+ buffer = 0;
+ for(i = 0; i < mem_entries; i++) {
+ unsigned long mstart, mend;
+ unsigned long msize;
+ unsigned long tbuffer;
+ if (mem->map[i].type != LB_MEM_RAM)
+ continue;
+ if (unpack_lb64(mem->map[i].start) > MAX_ADDR)
+ continue;
+ if (unpack_lb64(mem->map[i].size) < lb_size)
+ continue;
+ mstart = unpack_lb64(mem->map[i].start);
+ msize = MAX_ADDR - mstart +1;
+ if (msize > unpack_lb64(mem->map[i].size))
+ msize = unpack_lb64(mem->map[i].size);
+ mend = mstart + msize;
+ tbuffer = mend - lb_size;
+ if (tbuffer < buffer)
+ continue;
+ buffer = tbuffer;
+ }
+ bounce_buffer = buffer;
+ bounce_size = req_size;
+}
+
+static int valid_area(struct lb_memory *mem, unsigned long buffer,
+ unsigned long start, unsigned long len)
+{
+ /* Check through all of the memory segments and ensure
+ * the segment that was passed in is completely contained
+ * in RAM.
+ */
+ int i;
+ unsigned long end = start + len;
+ unsigned long mem_entries = (mem->size - sizeof(*mem)) /
+ sizeof(mem->map[0]);
+
+ /* See if I conflict with the bounce buffer */
+ if (end >= buffer) {
+ return 0;
+ }
+
+ /* Walk through the table of valid memory ranges and see if I
+ * have a match.
+ */
+ for(i = 0; i < mem_entries; i++) {
+ uint64_t mstart, mend;
+ uint32_t mtype;
+ mtype = mem->map[i].type;
+ mstart = unpack_lb64(mem->map[i].start);
+ mend = mstart + unpack_lb64(mem->map[i].size);
+ if ((mtype == LB_MEM_RAM) && (start >= mstart) && (end < mend)) {
+ break;
+ }
+ if ((mtype == LB_MEM_TABLE) && (start >= mstart) && (end < mend)) {
+ printk(BIOS_ERR, "Payload is overwriting coreboot tables.\n");
+ break;
+ }
+ }
+ if (i == mem_entries) {
+ if (start < (1024*1024) && end <=(1024*1024)) {
+ printk(BIOS_DEBUG, "Payload (probably SeaBIOS) loaded"
+ " into a reserved area in the lower 1MB\n");
+ return 1;
+ }
+ printk(BIOS_ERR, "No matching ram area found for range:\n");
+ printk(BIOS_ERR, " [0x%016lx, 0x%016lx)\n", start, end);
+ printk(BIOS_ERR, "Ram areas\n");
+ for(i = 0; i < mem_entries; i++) {
+ uint64_t mstart, mend;
+ uint32_t mtype;
+ mtype = mem->map[i].type;
+ mstart = unpack_lb64(mem->map[i].start);
+ mend = mstart + unpack_lb64(mem->map[i].size);
+ printk(BIOS_ERR, " [0x%016lx, 0x%016lx) %s\n",
+ (unsigned long)mstart,
+ (unsigned long)mend,
+ (mtype == LB_MEM_RAM)?"RAM":"Reserved");
+
+ }
+ return 0;
+ }
+ return 1;
+}
+
+
+static int overlaps_coreboot(struct segment *seg)
+{
+ unsigned long start, end;
+ start = seg->s_dstaddr;
+ end = start + seg->s_memsz;
+ return !((end <= lb_start) || (start >= lb_end));
+}
+
+static int relocate_segment(unsigned long buffer, struct segment *seg)
+{
+ /* Modify all segments that want to load onto coreboot
+ * to load onto the bounce buffer instead.
+ */
+ /* ret: 1 : A new segment is inserted before the seg.
+ * 0 : A new segment is inserted after the seg, or no new one.
+ */
+ unsigned long start, middle, end, ret = 0;
+
+ printk(BIOS_SPEW, "lb: [0x%016lx, 0x%016lx)\n",
+ lb_start, lb_end);
+
+ /* I don't conflict with coreboot so get out of here */
+ if (!overlaps_coreboot(seg))
+ return 0;
+
+ start = seg->s_dstaddr;
+ middle = start + seg->s_filesz;
+ end = start + seg->s_memsz;
+
+ printk(BIOS_SPEW, "segment: [0x%016lx, 0x%016lx, 0x%016lx)\n",
+ start, middle, end);
+
+ if (seg->compression == CBFS_COMPRESS_NONE) {
+ /* Slice off a piece at the beginning
+ * that doesn't conflict with coreboot.
+ */
+ if (start < lb_start) {
+ struct segment *new;
+ unsigned long len = lb_start - start;
+ new = malloc(sizeof(*new));
+ *new = *seg;
+ new->s_memsz = len;
+ seg->s_memsz -= len;
+ seg->s_dstaddr += len;
+ seg->s_srcaddr += len;
+ if (seg->s_filesz > len) {
+ new->s_filesz = len;
+ seg->s_filesz -= len;
+ } else {
+ seg->s_filesz = 0;
+ }
+
+ /* Order by stream offset */
+ new->next = seg;
+ new->prev = seg->prev;
+ seg->prev->next = new;
+ seg->prev = new;
+
+ /* compute the new value of start */
+ start = seg->s_dstaddr;
+
+ printk(BIOS_SPEW, " early: [0x%016lx, 0x%016lx, 0x%016lx)\n",
+ new->s_dstaddr,
+ new->s_dstaddr + new->s_filesz,
+ new->s_dstaddr + new->s_memsz);
+
+ ret = 1;
+ }
+
+ /* Slice off a piece at the end
+ * that doesn't conflict with coreboot
+ */
+ if (end > lb_end) {
+ unsigned long len = lb_end - start;
+ struct segment *new;
+ new = malloc(sizeof(*new));
+ *new = *seg;
+ seg->s_memsz = len;
+ new->s_memsz -= len;
+ new->s_dstaddr += len;
+ new->s_srcaddr += len;
+ if (seg->s_filesz > len) {
+ seg->s_filesz = len;
+ new->s_filesz -= len;
+ } else {
+ new->s_filesz = 0;
+ }
+ /* Order by stream offset */
+ new->next = seg->next;
+ new->prev = seg;
+ seg->next->prev = new;
+ seg->next = new;
+
+ printk(BIOS_SPEW, " late: [0x%016lx, 0x%016lx, 0x%016lx)\n",
+ new->s_dstaddr,
+ new->s_dstaddr + new->s_filesz,
+ new->s_dstaddr + new->s_memsz);
+ }
+ }
+
+ /* Now retarget this segment onto the bounce buffer */
+ /* sort of explanation: the buffer is a 1:1 mapping to coreboot.
+ * so you will make the dstaddr be this buffer, and it will get copied
+ * later to where coreboot lives.
+ */
+ seg->s_dstaddr = buffer + (seg->s_dstaddr - lb_start);
+
+ printk(BIOS_SPEW, " bounce: [0x%016lx, 0x%016lx, 0x%016lx)\n",
+ seg->s_dstaddr,
+ seg->s_dstaddr + seg->s_filesz,
+ seg->s_dstaddr + seg->s_memsz);
+
+ return ret;
+}
+
+
+static int build_self_segment_list(
+ struct segment *head,
+ struct lb_memory *mem,
+ struct cbfs_payload *payload, u32 *entry)
+{
+ struct segment *new;
+ struct segment *ptr;
+ struct cbfs_payload_segment *segment, *first_segment;
+ memset(head, 0, sizeof(*head));
+ head->next = head->prev = head;
+ first_segment = segment = &payload->segments;
+
+ while(1) {
+ printk(BIOS_DEBUG, "Loading segment from rom address 0x%p\n", segment);
+ switch(segment->type) {
+ case PAYLOAD_SEGMENT_PARAMS:
+ printk(BIOS_DEBUG, " parameter section (skipped)\n");
+ segment++;
+ continue;
+
+ case PAYLOAD_SEGMENT_CODE:
+ case PAYLOAD_SEGMENT_DATA:
+ printk(BIOS_DEBUG, " %s (compression=%x)\n",
+ segment->type == PAYLOAD_SEGMENT_CODE ? "code" : "data",
+ ntohl(segment->compression));
+ new = malloc(sizeof(*new));
+ new->s_dstaddr = ntohll(segment->load_addr);
+ new->s_memsz = ntohl(segment->mem_len);
+ new->compression = ntohl(segment->compression);
+
+ new->s_srcaddr = (u32) ((unsigned char *)first_segment)
+ + ntohl(segment->offset);
+ new->s_filesz = ntohl(segment->len);
+ printk(BIOS_DEBUG, " New segment dstaddr 0x%lx memsize 0x%lx srcaddr 0x%lx filesize 0x%lx\n",
+ new->s_dstaddr, new->s_memsz, new->s_srcaddr, new->s_filesz);
+ /* Clean up the values */
+ if (new->s_filesz > new->s_memsz) {
+ new->s_filesz = new->s_memsz;
+ }
+ printk(BIOS_DEBUG, " (cleaned up) New segment addr 0x%lx size 0x%lx offset 0x%lx filesize 0x%lx\n",
+ new->s_dstaddr, new->s_memsz, new->s_srcaddr, new->s_filesz);
+ break;
+
+ case PAYLOAD_SEGMENT_BSS:
+ printk(BIOS_DEBUG, " BSS 0x%p (%d byte)\n", (void *)
+ (intptr_t)ntohll(segment->load_addr),
+ ntohl(segment->mem_len));
+ new = malloc(sizeof(*new));
+ new->s_filesz = 0;
+ new->s_dstaddr = ntohll(segment->load_addr);
+ new->s_memsz = ntohl(segment->mem_len);
+ break;
+
+ case PAYLOAD_SEGMENT_ENTRY:
+ printk(BIOS_DEBUG, " Entry Point 0x%p\n", (void *) ntohl((u32) segment->load_addr));
+ *entry = ntohll(segment->load_addr);
+ /* Per definition, a payload always has the entry point
+ * as last segment. Thus, we use the occurence of the
+ * entry point as break condition for the loop.
+ * Can we actually just look at the number of section?
+ */
+ return 1;
+
+ default:
+ /* We found something that we don't know about. Throw
+ * hands into the sky and run away!
+ */
+ printk(BIOS_EMERG, "Bad segment type %x\n", segment->type);
+ return -1;
+ }
+
+ /* We have found another CODE, DATA or BSS segment */
+ segment++;
+
+ /* Find place where to insert our segment */
+ for(ptr = head->next; ptr != head; ptr = ptr->next) {
+ if (new->s_srcaddr < ntohll(segment->load_addr))
+ break;
+ }
+
+ /* Order by stream offset */
+ new->next = ptr;
+ new->prev = ptr->prev;
+ ptr->prev->next = new;
+ ptr->prev = new;
+ }
+
+ return 1;
+}
+
+static int load_self_segments(
+ struct segment *head,
+ struct lb_memory *mem,
+ struct cbfs_payload *payload)
+{
+ struct segment *ptr;
+
+ unsigned long bounce_high = lb_end;
+ for(ptr = head->next; ptr != head; ptr = ptr->next) {
+ if (!overlaps_coreboot(ptr))
+ continue;
+ if (ptr->s_dstaddr + ptr->s_memsz > bounce_high)
+ bounce_high = ptr->s_dstaddr + ptr->s_memsz;
+ }
+ get_bounce_buffer(mem, bounce_high - lb_start);
+ if (!bounce_buffer) {
+ printk(BIOS_ERR, "Could not find a bounce buffer...\n");
+ return 0;
+ }
+ for(ptr = head->next; ptr != head; ptr = ptr->next) {
+ /* Verify the memory addresses in the segment are valid */
+ if (!valid_area(mem, bounce_buffer, ptr->s_dstaddr, ptr->s_memsz))
+ return 0;
+ }
+ for(ptr = head->next; ptr != head; ptr = ptr->next) {
+ unsigned char *dest, *src;
+ printk(BIOS_DEBUG, "Loading Segment: addr: 0x%016lx memsz: 0x%016lx filesz: 0x%016lx\n",
+ ptr->s_dstaddr, ptr->s_memsz, ptr->s_filesz);
+
+ /* Modify the segment to load onto the bounce_buffer if necessary.
+ */
+ if (relocate_segment(bounce_buffer, ptr)) {
+ ptr = (ptr->prev)->prev;
+ continue;
+ }
+
+ printk(BIOS_DEBUG, "Post relocation: addr: 0x%016lx memsz: 0x%016lx filesz: 0x%016lx\n",
+ ptr->s_dstaddr, ptr->s_memsz, ptr->s_filesz);
+
+ /* Compute the boundaries of the segment */
+ dest = (unsigned char *)(ptr->s_dstaddr);
+ src = (unsigned char *)(ptr->s_srcaddr);
+
+ /* Copy data from the initial buffer */
+ if (ptr->s_filesz) {
+ unsigned char *middle, *end;
+ size_t len;
+ len = ptr->s_filesz;
+ switch(ptr->compression) {
+ case CBFS_COMPRESS_LZMA: {
+ printk(BIOS_DEBUG, "using LZMA\n");
+ len = ulzma(src, dest);
+ if (!len) /* Decompression Error. */
+ return 0;
+ break;
+ }
+#if CONFIG_COMPRESSED_PAYLOAD_NRV2B
+ case CBFS_COMPRESS_NRV2B: {
+ printk(BIOS_DEBUG, "using NRV2B\n");
+ unsigned long unrv2b(u8 *src, u8 *dst, unsigned long *ilen_p);
+ unsigned long tmp;
+ len = unrv2b(src, dest, &tmp);
+ break;
+ }
+#endif
+ case CBFS_COMPRESS_NONE: {
+ printk(BIOS_DEBUG, "it's not compressed!\n");
+ memcpy(dest, src, len);
+ break;
+ }
+ default:
+ printk(BIOS_INFO, "CBFS: Unknown compression type %d\n", ptr->compression);
+ return -1;
+ }
+ end = dest + ptr->s_memsz;
+ middle = dest + len;
+ printk(BIOS_SPEW, "[ 0x%08lx, %08lx, 0x%08lx) <- %08lx\n",
+ (unsigned long)dest,
+ (unsigned long)middle,
+ (unsigned long)end,
+ (unsigned long)src);
+
+ /* Zero the extra bytes between middle & end */
+ if (middle < end) {
+ printk(BIOS_DEBUG, "Clearing Segment: addr: 0x%016lx memsz: 0x%016lx\n",
+ (unsigned long)middle, (unsigned long)(end - middle));
+
+ /* Zero the extra bytes */
+ memset(middle, 0, end - middle);
+ }
+ /* Copy the data that's outside the area that shadows coreboot_ram */
+ printk(BIOS_DEBUG, "dest %p, end %p, bouncebuffer %lx\n", dest, end, bounce_buffer);
+ if ((unsigned long)end > bounce_buffer) {
+ if ((unsigned long)dest < bounce_buffer) {
+ unsigned char *from = dest;
+ unsigned char *to = (unsigned char*)(lb_start-(bounce_buffer-(unsigned long)dest));
+ unsigned long amount = bounce_buffer-(unsigned long)dest;
+ printk(BIOS_DEBUG, "move prefix around: from %p, to %p, amount: %lx\n", from, to, amount);
+ memcpy(to, from, amount);
+ }
+ if ((unsigned long)end > bounce_buffer + (lb_end - lb_start)) {
+ unsigned long from = bounce_buffer + (lb_end - lb_start);
+ unsigned long to = lb_end;
+ unsigned long amount = (unsigned long)end - from;
+ printk(BIOS_DEBUG, "move suffix around: from %lx, to %lx, amount: %lx\n", from, to, amount);
+ memcpy((char*)to, (char*)from, amount);
+ }
+ }
+ }
+ }
+ return 1;
+}
+
+int selfboot(struct lb_memory *mem, struct cbfs_payload *payload)
+{
+ u32 entry=0;
+ struct segment head;
+
+ /* Preprocess the self segments */
+ if (!build_self_segment_list(&head, mem, payload, &entry))
+ goto out;
+
+ /* Load the segments */
+ if (!load_self_segments(&head, mem, payload))
+ goto out;
+
+ printk(BIOS_SPEW, "Loaded segments\n");
+
+ /* Reset to booting from this image as late as possible */
+ boot_successful();
+
+ printk(BIOS_DEBUG, "Jumping to boot code at %x\n", entry);
+ post_code(POST_ENTER_ELF_BOOT);
+
+#if CONFIG_COLLECT_TIMESTAMPS
+ timestamp_add_now(TS_SELFBOOT_JUMP);
+#endif
+
+ /* Before we go off to run the payload, see if
+ * we stayed within our bounds.
+ */
+ checkstack(_estack, 0);
+
+ /* Jump to kernel */
+ jmp_to_elf_entry((void*)entry, bounce_buffer, bounce_size);
+ return 1;
+
+out:
+ return 0;
+}
+
+void *cbfs_load_payload(struct lb_memory *lb_mem, const char *name)
+{
+ struct cbfs_payload *payload;
+
+ payload = (struct cbfs_payload *)cbfs_find_file(name, CBFS_TYPE_PAYLOAD);
+
+ return payload;
+}
+
generated by cgit v1.2.3 (git 2.25.1) at 2024-11-11 04:21:45 +0000