--- /dev/null
+// Disk setup and access
+//
+// 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" // struct ata_s
+#include "biosvar.h" // GET_GLOBAL
+#include "cmos.h" // inb_cmos
+#include "util.h" // dprintf
+#include "ata.h" // process_ata_op
+#include "ahci.h" // process_ahci_op
+#include "usb-msc.h" // process_usb_op
+#include "virtio-blk.h" // process_virtio_op
+
+u8 FloppyCount VAR16VISIBLE;
+u8 CDCount;
+struct drive_s *IDMap[3][CONFIG_MAX_EXTDRIVE] VAR16VISIBLE;
+u8 *bounce_buf_fl VAR16VISIBLE;
+
+struct drive_s *
+getDrive(u8 exttype, u8 extdriveoffset)
+{
+ if (extdriveoffset >= ARRAY_SIZE(IDMap[0]))
+ return NULL;
+ struct drive_s *drive_gf = GET_GLOBAL(IDMap[exttype][extdriveoffset]);
+ if (!drive_gf)
+ return NULL;
+ return GLOBALFLAT2GLOBAL(drive_gf);
+}
+
+int getDriveId(u8 exttype, struct drive_s *drive_g)
+{
+ int i;
+ for (i = 0; i < ARRAY_SIZE(IDMap[0]); i++)
+ if (getDrive(exttype, i) == drive_g)
+ return i;
+ return -1;
+}
+
+int bounce_buf_init(void)
+{
+ if (bounce_buf_fl)
+ return 0;
+
+ u8 *buf = malloc_low(CDROM_SECTOR_SIZE);
+ if (!buf) {
+ warn_noalloc();
+ return -1;
+ }
+ bounce_buf_fl = buf;
+ return 0;
+}
+
+/****************************************************************
+ * Disk geometry translation
+ ****************************************************************/
+
+static u8
+get_translation(struct drive_s *drive_g)
+{
+ u8 type = GET_GLOBAL(drive_g->type);
+ if (! CONFIG_COREBOOT && type == DTYPE_ATA) {
+ // Emulators pass in the translation info via nvram.
+ u8 ataid = GET_GLOBAL(drive_g->cntl_id);
+ u8 channel = ataid / 2;
+ u8 translation = inb_cmos(CMOS_BIOS_DISKTRANSFLAG + channel/2);
+ translation >>= 2 * (ataid % 4);
+ translation &= 0x03;
+ return translation;
+ }
+
+ // Otherwise use a heuristic to determine translation type.
+ u16 heads = GET_GLOBAL(drive_g->pchs.heads);
+ u16 cylinders = GET_GLOBAL(drive_g->pchs.cylinders);
+ u16 spt = GET_GLOBAL(drive_g->pchs.spt);
+ u64 sectors = GET_GLOBAL(drive_g->sectors);
+ u64 psectors = (u64)heads * cylinders * spt;
+ if (!heads || !cylinders || !spt || psectors > sectors)
+ // pchs doesn't look valid - use LBA.
+ return TRANSLATION_LBA;
+
+ if (cylinders <= 1024 && heads <= 16 && spt <= 63)
+ return TRANSLATION_NONE;
+ if (cylinders * heads <= 131072)
+ return TRANSLATION_LARGE;
+ return TRANSLATION_LBA;
+}
+
+static void
+setup_translation(struct drive_s *drive_g)
+{
+ u8 translation = get_translation(drive_g);
+ SET_GLOBAL(drive_g->translation, translation);
+
+ u16 heads = GET_GLOBAL(drive_g->pchs.heads);
+ u16 cylinders = GET_GLOBAL(drive_g->pchs.cylinders);
+ u16 spt = GET_GLOBAL(drive_g->pchs.spt);
+ u64 sectors = GET_GLOBAL(drive_g->sectors);
+ const char *desc = NULL;
+
+ switch (translation) {
+ default:
+ case TRANSLATION_NONE:
+ desc = "none";
+ break;
+ case TRANSLATION_LBA:
+ desc = "lba";
+ spt = 63;
+ if (sectors > 63*255*1024) {
+ heads = 255;
+ cylinders = 1024;
+ break;
+ }
+ u32 sect = (u32)sectors / 63;
+ heads = sect / 1024;
+ if (heads>128)
+ heads = 255;
+ else if (heads>64)
+ heads = 128;
+ else if (heads>32)
+ heads = 64;
+ else if (heads>16)
+ heads = 32;
+ else
+ heads = 16;
+ cylinders = sect / heads;
+ break;
+ case TRANSLATION_RECHS:
+ desc = "r-echs";
+ // Take care not to overflow
+ if (heads==16) {
+ if (cylinders>61439)
+ cylinders=61439;
+ heads=15;
+ cylinders = (u16)((u32)(cylinders)*16/15);
+ }
+ // then go through the large bitshift process
+ case TRANSLATION_LARGE:
+ if (translation == TRANSLATION_LARGE)
+ desc = "large";
+ while (cylinders > 1024) {
+ cylinders >>= 1;
+ heads <<= 1;
+
+ // If we max out the head count
+ if (heads > 127)
+ break;
+ }
+ break;
+ }
+ // clip to 1024 cylinders in lchs
+ if (cylinders > 1024)
+ cylinders = 1024;
+ dprintf(1, "drive %p: PCHS=%u/%d/%d translation=%s LCHS=%d/%d/%d s=%d\n"
+ , drive_g
+ , drive_g->pchs.cylinders, drive_g->pchs.heads, drive_g->pchs.spt
+ , desc
+ , cylinders, heads, spt
+ , (u32)sectors);
+
+ SET_GLOBAL(drive_g->lchs.heads, heads);
+ SET_GLOBAL(drive_g->lchs.cylinders, cylinders);
+ SET_GLOBAL(drive_g->lchs.spt, spt);
+}
+
+
+/****************************************************************
+ * Drive mapping
+ ****************************************************************/
+
+// Fill in Fixed Disk Parameter Table (located in ebda).
+static void
+fill_fdpt(struct drive_s *drive_g, int hdid)
+{
+ if (hdid > 1)
+ return;
+
+ u16 nlc = GET_GLOBAL(drive_g->lchs.cylinders);
+ u16 nlh = GET_GLOBAL(drive_g->lchs.heads);
+ u16 nlspt = GET_GLOBAL(drive_g->lchs.spt);
+
+ u16 npc = GET_GLOBAL(drive_g->pchs.cylinders);
+ u16 nph = GET_GLOBAL(drive_g->pchs.heads);
+ u16 npspt = GET_GLOBAL(drive_g->pchs.spt);
+
+ struct fdpt_s *fdpt = &get_ebda_ptr()->fdpt[hdid];
+ fdpt->precompensation = 0xffff;
+ fdpt->drive_control_byte = 0xc0 | ((nph > 8) << 3);
+ fdpt->landing_zone = npc;
+ fdpt->cylinders = nlc;
+ fdpt->heads = nlh;
+ fdpt->sectors = nlspt;
+
+ if (nlc != npc || nlh != nph || nlspt != npspt) {
+ // Logical mapping present - use extended structure.
+
+ // complies with Phoenix style Translated Fixed Disk Parameter
+ // Table (FDPT)
+ fdpt->phys_cylinders = npc;
+ fdpt->phys_heads = nph;
+ fdpt->phys_sectors = npspt;
+ fdpt->a0h_signature = 0xa0;
+
+ // Checksum structure.
+ fdpt->checksum -= checksum(fdpt, sizeof(*fdpt));
+ }
+
+ if (hdid == 0)
+ SET_IVT(0x41, SEGOFF(get_ebda_seg(), offsetof(
+ struct extended_bios_data_area_s, fdpt[0])));
+ else
+ SET_IVT(0x46, SEGOFF(get_ebda_seg(), offsetof(
+ struct extended_bios_data_area_s, fdpt[1])));
+}
+
+// Find spot to add a drive
+static void
+add_drive(struct drive_s **idmap, u8 *count, struct drive_s *drive_g)
+{
+ if (*count >= ARRAY_SIZE(IDMap[0])) {
+ warn_noalloc();
+ return;
+ }
+ idmap[*count] = drive_g;
+ *count = *count + 1;
+}
+
+// Map a hard drive
+void
+map_hd_drive(struct drive_s *drive_g)
+{
+ ASSERT32FLAT();
+ struct bios_data_area_s *bda = MAKE_FLATPTR(SEG_BDA, 0);
+ int hdid = bda->hdcount;
+ dprintf(3, "Mapping hd drive %p to %d\n", drive_g, hdid);
+ add_drive(IDMap[EXTTYPE_HD], &bda->hdcount, drive_g);
+
+ // Setup disk geometry translation.
+ setup_translation(drive_g);
+
+ // Fill "fdpt" structure.
+ fill_fdpt(drive_g, hdid);
+}
+
+// Map a cd
+void
+map_cd_drive(struct drive_s *drive_g)
+{
+ dprintf(3, "Mapping cd drive %p\n", drive_g);
+ add_drive(IDMap[EXTTYPE_CD], &CDCount, drive_g);
+}
+
+// Map a floppy
+void
+map_floppy_drive(struct drive_s *drive_g)
+{
+ dprintf(3, "Mapping floppy drive %p\n", drive_g);
+ add_drive(IDMap[EXTTYPE_FLOPPY], &FloppyCount, drive_g);
+
+ // Update equipment word bits for floppy
+ if (FloppyCount == 1) {
+ // 1 drive, ready for boot
+ SETBITS_BDA(equipment_list_flags, 0x01);
+ SET_BDA(floppy_harddisk_info, 0x07);
+ } else if (FloppyCount >= 2) {
+ // 2 drives, ready for boot
+ SETBITS_BDA(equipment_list_flags, 0x41);
+ SET_BDA(floppy_harddisk_info, 0x77);
+ }
+}
+
+
+/****************************************************************
+ * 16bit calling interface
+ ****************************************************************/
+
+// Execute a disk_op request.
+int
+process_op(struct disk_op_s *op)
+{
+ ASSERT16();
+ u8 type = GET_GLOBAL(op->drive_g->type);
+ switch (type) {
+ case DTYPE_FLOPPY:
+ return process_floppy_op(op);
+ case DTYPE_ATA:
+ return process_ata_op(op);
+ case DTYPE_ATAPI:
+ return process_atapi_op(op);
+ case DTYPE_RAMDISK:
+ return process_ramdisk_op(op);
+ case DTYPE_CDEMU:
+ return process_cdemu_op(op);
+ case DTYPE_USB:
+ return process_usb_op(op);
+ case DTYPE_VIRTIO:
+ return process_virtio_op(op);
+ case DTYPE_AHCI:
+ return process_ahci_op(op);
+ default:
+ op->count = 0;
+ return DISK_RET_EPARAM;
+ }
+}
+
+// Execute a "disk_op_s" request - this runs on a stack in the ebda.
+static int
+__send_disk_op(struct disk_op_s *op_far, u16 op_seg)
+{
+ struct disk_op_s dop;
+ memcpy_far(GET_SEG(SS), &dop
+ , op_seg, op_far
+ , sizeof(dop));
+
+ dprintf(DEBUG_HDL_13, "disk_op d=%p lba=%d buf=%p count=%d cmd=%d\n"
+ , dop.drive_g, (u32)dop.lba, dop.buf_fl
+ , dop.count, dop.command);
+
+ int status = process_op(&dop);
+
+ // Update count with total sectors transferred.
+ SET_FARVAR(op_seg, op_far->count, dop.count);
+
+ return status;
+}
+
+// Execute a "disk_op_s" request by jumping to a stack in the ebda.
+int
+send_disk_op(struct disk_op_s *op)
+{
+ ASSERT16();
+ if (! CONFIG_DRIVES)
+ return -1;
+
+ return stack_hop((u32)op, GET_SEG(SS), __send_disk_op);
+}
