--- /dev/null
+// Support for booting from cdroms (the "El Torito" spec).
+//
+// Copyright (C) 2008,2009 Kevin O'Connor <kevin@koconnor.net>
+// Copyright (C) 2002 MandrakeSoft S.A.
+//
+// This file may be distributed under the terms of the GNU LGPLv3 license.
+
+#include "disk.h" // cdrom_13
+#include "util.h" // memset
+#include "bregs.h" // struct bregs
+#include "biosvar.h" // GET_EBDA
+#include "ata.h" // ATA_CMD_REQUEST_SENSE
+#include "blockcmd.h" // CDB_CMD_REQUEST_SENSE
+
+
+/****************************************************************
+ * CD emulation
+ ****************************************************************/
+
+struct drive_s *cdemu_drive_gf VAR16VISIBLE;
+
+static int
+cdemu_read(struct disk_op_s *op)
+{
+ u16 ebda_seg = get_ebda_seg();
+ struct drive_s *drive_g;
+ drive_g = GLOBALFLAT2GLOBAL(GET_EBDA2(ebda_seg, cdemu.emulated_drive_gf));
+ struct disk_op_s dop;
+ dop.drive_g = drive_g;
+ dop.command = op->command;
+ dop.lba = GET_EBDA2(ebda_seg, cdemu.ilba) + op->lba / 4;
+
+ int count = op->count;
+ op->count = 0;
+ u8 *cdbuf_fl = GET_GLOBAL(bounce_buf_fl);
+
+ if (op->lba & 3) {
+ // Partial read of first block.
+ dop.count = 1;
+ dop.buf_fl = cdbuf_fl;
+ int ret = process_op(&dop);
+ if (ret)
+ return ret;
+ u8 thiscount = 4 - (op->lba & 3);
+ if (thiscount > count)
+ thiscount = count;
+ count -= thiscount;
+ memcpy_fl(op->buf_fl, cdbuf_fl + (op->lba & 3) * 512, thiscount * 512);
+ op->buf_fl += thiscount * 512;
+ op->count += thiscount;
+ dop.lba++;
+ }
+
+ if (count > 3) {
+ // Read n number of regular blocks.
+ dop.count = count / 4;
+ dop.buf_fl = op->buf_fl;
+ int ret = process_op(&dop);
+ op->count += dop.count * 4;
+ if (ret)
+ return ret;
+ u8 thiscount = count & ~3;
+ count &= 3;
+ op->buf_fl += thiscount * 512;
+ dop.lba += thiscount / 4;
+ }
+
+ if (count) {
+ // Partial read on last block.
+ dop.count = 1;
+ dop.buf_fl = cdbuf_fl;
+ int ret = process_op(&dop);
+ if (ret)
+ return ret;
+ u8 thiscount = count;
+ memcpy_fl(op->buf_fl, cdbuf_fl, thiscount * 512);
+ op->count += thiscount;
+ }
+
+ return DISK_RET_SUCCESS;
+}
+
+int
+process_cdemu_op(struct disk_op_s *op)
+{
+ if (!CONFIG_CDROM_EMU)
+ return 0;
+
+ switch (op->command) {
+ case CMD_READ:
+ return cdemu_read(op);
+ case CMD_WRITE:
+ case CMD_FORMAT:
+ return DISK_RET_EWRITEPROTECT;
+ case CMD_VERIFY:
+ case CMD_RESET:
+ case CMD_SEEK:
+ case CMD_ISREADY:
+ return DISK_RET_SUCCESS;
+ default:
+ op->count = 0;
+ return DISK_RET_EPARAM;
+ }
+}
+
+void
+cdemu_setup(void)
+{
+ if (!CONFIG_CDROM_EMU)
+ return;
+ if (!CDCount)
+ return;
+ if (bounce_buf_init() < 0)
+ return;
+
+ struct drive_s *drive_g = malloc_fseg(sizeof(*drive_g));
+ if (!drive_g) {
+ warn_noalloc();
+ free(drive_g);
+ return;
+ }
+ cdemu_drive_gf = drive_g;
+ memset(drive_g, 0, sizeof(*drive_g));
+ drive_g->type = DTYPE_CDEMU;
+ drive_g->blksize = DISK_SECTOR_SIZE;
+ drive_g->sectors = (u64)-1;
+}
+
+struct eltorito_s {
+ u8 size;
+ u8 media;
+ u8 emulated_drive;
+ u8 controller_index;
+ u32 ilba;
+ u16 device_spec;
+ u16 buffer_segment;
+ u16 load_segment;
+ u16 sector_count;
+ u8 cylinders;
+ u8 sectors;
+ u8 heads;
+};
+
+#define SET_INT13ET(regs,var,val) \
+ SET_FARVAR((regs)->ds, ((struct eltorito_s*)((regs)->si+0))->var, (val))
+
+// ElTorito - Terminate disk emu
+void
+cdemu_134b(struct bregs *regs)
+{
+ // FIXME ElTorito Hardcoded
+ u16 ebda_seg = get_ebda_seg();
+ SET_INT13ET(regs, size, 0x13);
+ SET_INT13ET(regs, media, GET_EBDA2(ebda_seg, cdemu.media));
+ SET_INT13ET(regs, emulated_drive
+ , GET_EBDA2(ebda_seg, cdemu.emulated_extdrive));
+ struct drive_s *drive_gf = GET_EBDA2(ebda_seg, cdemu.emulated_drive_gf);
+ u8 cntl_id = 0;
+ if (drive_gf)
+ cntl_id = GET_GLOBALFLAT(drive_gf->cntl_id);
+ SET_INT13ET(regs, controller_index, cntl_id / 2);
+ SET_INT13ET(regs, device_spec, cntl_id % 2);
+ SET_INT13ET(regs, ilba, GET_EBDA2(ebda_seg, cdemu.ilba));
+ SET_INT13ET(regs, buffer_segment, GET_EBDA2(ebda_seg, cdemu.buffer_segment));
+ SET_INT13ET(regs, load_segment, GET_EBDA2(ebda_seg, cdemu.load_segment));
+ SET_INT13ET(regs, sector_count, GET_EBDA2(ebda_seg, cdemu.sector_count));
+ SET_INT13ET(regs, cylinders, GET_EBDA2(ebda_seg, cdemu.lchs.cylinders));
+ SET_INT13ET(regs, sectors, GET_EBDA2(ebda_seg, cdemu.lchs.spt));
+ SET_INT13ET(regs, heads, GET_EBDA2(ebda_seg, cdemu.lchs.heads));
+
+ // If we have to terminate emulation
+ if (regs->al == 0x00) {
+ // FIXME ElTorito Various. Should be handled accordingly to spec
+ SET_EBDA2(ebda_seg, cdemu.active, 0x00); // bye bye
+
+ // XXX - update floppy/hd count.
+ }
+
+ disk_ret(regs, DISK_RET_SUCCESS);
+}
+
+
+/****************************************************************
+ * CD booting
+ ****************************************************************/
+
+static int
+atapi_is_ready(struct disk_op_s *op)
+{
+ dprintf(6, "atapi_is_ready (drive=%p)\n", op->drive_g);
+
+ /* Retry READ CAPACITY for 5 seconds unless MEDIUM NOT PRESENT is
+ * reported by the device. If the device reports "IN PROGRESS",
+ * 30 seconds is added. */
+ struct cdbres_read_capacity info;
+ int in_progress = 0;
+ u64 end = calc_future_tsc(5000);
+ for (;;) {
+ if (check_tsc(end)) {
+ dprintf(1, "read capacity failed\n");
+ return -1;
+ }
+
+ int ret = cdb_read_capacity(op, &info);
+ if (!ret)
+ // Success
+ break;
+
+ struct cdbres_request_sense sense;
+ ret = cdb_get_sense(op, &sense);
+ if (ret)
+ // Error - retry.
+ continue;
+
+ // Sense succeeded.
+ if (sense.asc == 0x3a) { /* MEDIUM NOT PRESENT */
+ dprintf(1, "Device reports MEDIUM NOT PRESENT\n");
+ return -1;
+ }
+
+ if (sense.asc == 0x04 && sense.ascq == 0x01 && !in_progress) {
+ /* IN PROGRESS OF BECOMING READY */
+ printf("Waiting for device to detect medium... ");
+ /* Allow 30 seconds more */
+ end = calc_future_tsc(30000);
+ in_progress = 1;
+ }
+ }
+
+ u32 blksize = ntohl(info.blksize), sectors = ntohl(info.sectors);
+ if (blksize != GET_GLOBAL(op->drive_g->blksize)) {
+ printf("Unsupported sector size %u\n", blksize);
+ return -1;
+ }
+
+ dprintf(6, "sectors=%u\n", sectors);
+ printf("%dMB medium detected\n", sectors>>(20-11));
+ return 0;
+}
+
+int
+cdrom_boot(struct drive_s *drive_g)
+{
+ struct disk_op_s dop;
+ int cdid = getDriveId(EXTTYPE_CD, drive_g);
+ memset(&dop, 0, sizeof(dop));
+ dop.drive_g = drive_g;
+ if (!dop.drive_g || cdid < 0)
+ return 1;
+
+ int ret = atapi_is_ready(&dop);
+ if (ret)
+ dprintf(1, "atapi_is_ready returned %d\n", ret);
+
+ // Read the Boot Record Volume Descriptor
+ u8 buffer[2048];
+ dop.lba = 0x11;
+ dop.count = 1;
+ dop.buf_fl = MAKE_FLATPTR(GET_SEG(SS), buffer);
+ ret = cdb_read(&dop);
+ if (ret)
+ return 3;
+
+ // Validity checks
+ if (buffer[0])
+ return 4;
+ if (strcmp((char*)&buffer[1], "CD001\001EL TORITO SPECIFICATION") != 0)
+ return 5;
+
+ // ok, now we calculate the Boot catalog address
+ u32 lba = *(u32*)&buffer[0x47];
+
+ // And we read the Boot Catalog
+ dop.lba = lba;
+ dop.count = 1;
+ ret = cdb_read(&dop);
+ if (ret)
+ return 7;
+
+ // Validation entry
+ if (buffer[0x00] != 0x01)
+ return 8; // Header
+ if (buffer[0x01] != 0x00)
+ return 9; // Platform
+ if (buffer[0x1E] != 0x55)
+ return 10; // key 1
+ if (buffer[0x1F] != 0xAA)
+ return 10; // key 2
+
+ // Initial/Default Entry
+ if (buffer[0x20] != 0x88)
+ return 11; // Bootable
+
+ u16 ebda_seg = get_ebda_seg();
+ u8 media = buffer[0x21];
+ SET_EBDA2(ebda_seg, cdemu.media, media);
+
+ SET_EBDA2(ebda_seg, cdemu.emulated_drive_gf, dop.drive_g);
+
+ u16 boot_segment = *(u16*)&buffer[0x22];
+ if (!boot_segment)
+ boot_segment = 0x07C0;
+ SET_EBDA2(ebda_seg, cdemu.load_segment, boot_segment);
+ SET_EBDA2(ebda_seg, cdemu.buffer_segment, 0x0000);
+
+ u16 nbsectors = *(u16*)&buffer[0x26];
+ SET_EBDA2(ebda_seg, cdemu.sector_count, nbsectors);
+
+ lba = *(u32*)&buffer[0x28];
+ SET_EBDA2(ebda_seg, cdemu.ilba, lba);
+
+ // And we read the image in memory
+ dop.lba = lba;
+ dop.count = DIV_ROUND_UP(nbsectors, 4);
+ dop.buf_fl = MAKE_FLATPTR(boot_segment, 0);
+ ret = cdb_read(&dop);
+ if (ret)
+ return 12;
+
+ if (media == 0) {
+ // No emulation requested - return success.
+ SET_EBDA2(ebda_seg, cdemu.emulated_extdrive, EXTSTART_CD + cdid);
+ return 0;
+ }
+
+ // Emulation of a floppy/harddisk requested
+ if (! CONFIG_CDROM_EMU || !cdemu_drive_gf)
+ return 13;
+
+ // Set emulated drive id and increase bios installed hardware
+ // number of devices
+ if (media < 4) {
+ // Floppy emulation
+ SET_EBDA2(ebda_seg, cdemu.emulated_extdrive, 0x00);
+ // XXX - get and set actual floppy count.
+ SETBITS_BDA(equipment_list_flags, 0x41);
+
+ switch (media) {
+ case 0x01: // 1.2M floppy
+ SET_EBDA2(ebda_seg, cdemu.lchs.spt, 15);
+ SET_EBDA2(ebda_seg, cdemu.lchs.cylinders, 80);
+ SET_EBDA2(ebda_seg, cdemu.lchs.heads, 2);
+ break;
+ case 0x02: // 1.44M floppy
+ SET_EBDA2(ebda_seg, cdemu.lchs.spt, 18);
+ SET_EBDA2(ebda_seg, cdemu.lchs.cylinders, 80);
+ SET_EBDA2(ebda_seg, cdemu.lchs.heads, 2);
+ break;
+ case 0x03: // 2.88M floppy
+ SET_EBDA2(ebda_seg, cdemu.lchs.spt, 36);
+ SET_EBDA2(ebda_seg, cdemu.lchs.cylinders, 80);
+ SET_EBDA2(ebda_seg, cdemu.lchs.heads, 2);
+ break;
+ }
+ } else {
+ // Harddrive emulation
+ SET_EBDA2(ebda_seg, cdemu.emulated_extdrive, 0x80);
+ SET_BDA(hdcount, GET_BDA(hdcount) + 1);
+
+ // Peak at partition table to get chs.
+ struct mbr_s *mbr = (void*)0;
+ u8 sptcyl = GET_FARVAR(boot_segment, mbr->partitions[0].last.sptcyl);
+ u8 cyllow = GET_FARVAR(boot_segment, mbr->partitions[0].last.cyllow);
+ u8 heads = GET_FARVAR(boot_segment, mbr->partitions[0].last.heads);
+
+ SET_EBDA2(ebda_seg, cdemu.lchs.spt, sptcyl & 0x3f);
+ SET_EBDA2(ebda_seg, cdemu.lchs.cylinders
+ , ((sptcyl<<2)&0x300) + cyllow + 1);
+ SET_EBDA2(ebda_seg, cdemu.lchs.heads, heads + 1);
+ }
+
+ // everything is ok, so from now on, the emulation is active
+ SET_EBDA2(ebda_seg, cdemu.active, 0x01);
+ dprintf(6, "cdemu media=%d\n", media);
+
+ return 0;
+}
