/*      $NetBSD: ata_raid_via.c,v 1.11 2025/03/11 16:51:31 andvar Exp $ */

/*-
 * Copyright (c) 2000,2001,2002 Søren Schmidt <sos@FreeBSD.org>
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer,
 *    without modification, immediately at the beginning of the file.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. The name of the author may not be used to endorse or promote products
 *    derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

/*
 * Support for parsing VIA V-RAID ATA RAID controller configuration blocks.
 *
 * Adapted to NetBSD by Tim Rightnour (garbled@netbsd.org)
 */

#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: ata_raid_via.c,v 1.11 2025/03/11 16:51:31 andvar Exp $");

#include <sys/param.h>
#include <sys/buf.h>
#include <sys/bufq.h>
#include <sys/conf.h>
#include <sys/device.h>
#include <sys/disk.h>
#include <sys/disklabel.h>
#include <sys/fcntl.h>
#include <sys/vnode.h>
#include <sys/kauth.h>

#include <miscfs/specfs/specdev.h>

#include <dev/ata/atareg.h>
#include <dev/ata/atavar.h>
#include <dev/ata/wdvar.h>

#include <dev/ata/ata_raidreg.h>
#include <dev/ata/ata_raidvar.h>

#ifdef ATA_RAID_DEBUG
#define DPRINTF(x)      printf x
#else
#define DPRINTF(x)      /* nothing */
#endif

#ifdef ATA_RAID_DEBUG
static const char *
ata_raid_via_type(int type)
{
        static char buffer[16];

        switch (type) {
        case VIA_T_RAID0:   return "RAID0";
        case VIA_T_RAID1:   return "RAID1";
        case VIA_T_RAID5:   return "RAID5";
        case VIA_T_RAID01:  return "RAID0+1";
        case VIA_T_SPAN:    return "SPAN";
        default:
                snprintf(buffer, sizeof(buffer), "UNKNOWN 0x%02x", type);
                return buffer;
        }
}

static void
ata_raid_via_print_info(struct via_raid_conf *info)
{
        int i;
  
        printf("*************** ATA VIA Metadata ****************\n");
        printf("magic               0x%02x\n", info->magic);
        printf("dummy_0             0x%02x\n", info->dummy_0);
        printf("type                %s\n",
            ata_raid_via_type(info->type & VIA_T_MASK));
        printf("bootable            %d\n", info->type & VIA_T_BOOTABLE);
        printf("unknown             %d\n", info->type & VIA_T_UNKNOWN);
        printf("disk_index          0x%02x\n", info->disk_index);
        printf("stripe_layout       0x%02x\n", info->stripe_layout);
        printf(" stripe_disks       %d\n", info->stripe_layout & VIA_L_DISKS);
        printf(" stripe_sectors     %d\n",
            0x08 << ((info->stripe_layout & VIA_L_MASK) >> VIA_L_SHIFT));
        printf("disk_sectors        %ju\n", info->disk_sectors);
        printf("disk_id             0x%08x\n", info->disk_id);
        printf("DISK#   disk_id\n");
        for (i = 0; i < 8; i++) {
        if (info->disks[i])
                printf("  %d    0x%08x\n", i, info->disks[i]);
        }    
        printf("checksum            0x%02x\n", info->checksum);
        printf("=================================================\n");
}
#endif

int
ata_raid_read_config_via(struct wd_softc *sc)
{
        struct dk_softc *dksc = &sc->sc_dksc;
        struct via_raid_conf *info;
        struct vnode *vp;
        int bmajor, error;
        dev_t dev;
        uint32_t drive;
        uint8_t checksum, checksum_alt, byte3, *ptr;
        int count, disk;
        struct ataraid_array_info *aai;
        struct ataraid_disk_info *adi;

        info = kmem_zalloc(sizeof(*info), KM_SLEEP);

        bmajor = devsw_name2blk(dksc->sc_xname, NULL, 0);

        /* Get a vnode for the raw partition of this disk. */
        dev = MAKEDISKDEV(bmajor, device_unit(dksc->sc_dev), RAW_PART);
        error = bdevvp(dev, &vp);
        if (error)
                goto out;

        vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
        error = VOP_OPEN(vp, FREAD, NOCRED);
        if (error) {
                vput(vp);
                goto out;
        }

        error = ata_raid_config_block_rw(vp, VIA_LBA(sc), info,
            sizeof(*info), B_READ);
        VOP_CLOSE(vp, FREAD, NOCRED);
        vput(vp);
        if (error) {
                aprint_error_dev(dksc->sc_dev,
                    "error %d reading VIA V-RAID config block\n", error);
                goto out;
        }

#ifdef ATA_RAID_DEBUG
        ata_raid_via_print_info(info);
        printf("MAGIC == 0x%02x\n", info->magic);
#endif

        /* Check the signature. */
        if (info->magic != VIA_MAGIC) {
                DPRINTF(("%s: VIA V-RAID signature check failed\n",
                    dksc->sc_xname));
                error = ESRCH;
                goto out;
        }

        /* calculate checksum and compare for valid */
        for (byte3 = 0, checksum = 0, ptr = (uint8_t *)info, count = 0;
            count < 50; count++)
                if (count == 3)
                        byte3 = *ptr++;
                else
                        checksum += *ptr++;
        checksum_alt = checksum + (byte3 & ~VIA_T_BOOTABLE);
        checksum += byte3;
        if (checksum != info->checksum && checksum_alt != info->checksum) {
                DPRINTF(("%s: VIA V-RAID checksum failed 0x%02x != "
                    "0x%02x or 0x%02x\n", dksc->sc_xname,
                    info->checksum, checksum, checksum_alt));
                error = ESRCH;
                goto out;
        }
        
        /*
         * Lookup or allocate a new array info structure for
         * this array. Use the serial number of disk0 as the array#
         */
        aai = ata_raid_get_array_info(ATA_RAID_TYPE_VIA, info->disks[0]);

        aai->aai_status = AAI_S_READY;

        switch (info->type & VIA_T_MASK) {
        case VIA_T_RAID0:
                aai->aai_level = AAI_L_RAID0;
                aai->aai_width = info->stripe_layout & VIA_L_DISKS;
                aai->aai_capacity = aai->aai_width * info->disk_sectors;
                break;

        case VIA_T_RAID1:
                aai->aai_level = AAI_L_RAID1;
                aai->aai_width = 1;
                aai->aai_capacity = aai->aai_width * info->disk_sectors;
                break;

        case VIA_T_RAID5:
                aai->aai_level = AAI_L_RAID5;
                aai->aai_width = info->stripe_layout & VIA_L_DISKS;
                aai->aai_capacity = (aai->aai_width - 1) * info->disk_sectors;
                break;

        case VIA_T_SPAN:
                aai->aai_level = AAI_L_SPAN;
                aai->aai_width = 1;
                aai->aai_capacity += info->disk_sectors; /* XXX ??? */
                break;

        default:
                aprint_error_dev(dksc->sc_dev,
                    "unknown VIA V-RAID type 0x%02x\n", info->type);
                error = EINVAL;
                goto out;
        }

        aai->aai_type = ATA_RAID_TYPE_VIA;
        /*
         * VIA V-RAID supports up to four drives in RAID 0 and JBOD
         * configurations and up to two drives in a RAID 1 configuration.
         */
        for (count = 0, disk = 0; disk < 4; disk++)
                if (info->disks[disk])
                        count++;
        aai->aai_interleave =
                0x08 << ((info->stripe_layout & VIA_L_MASK) >> VIA_L_SHIFT);
        aai->aai_ndisks = count;
        aai->aai_heads = 255;
        aai->aai_sectors = 63;
        aai->aai_cylinders = aai->aai_capacity / (63 * 255);
        aai->aai_offset = 0;
        aai->aai_reserved = 1;

        /* XXX - bogus.  RAID1 shouldn't really have an interleave */
        if (aai->aai_interleave == 0)
                aai->aai_interleave = aai->aai_capacity;

        /*
         * VIA V-RAID configuration blocks store the disk index as a value
         * incrementing by 0x04 (0x00, 0x04, 0x08, 0x0C).  Therefore, shift
         * the value left by 2 to obtain the disk number.
         */
        drive = info->disk_index >> 2;
        if (drive >= aai->aai_ndisks) {
                aprint_error_dev(dksc->sc_dev,
                    "drive number %d doesn't make sense within %d-disk "
                    "array\n", drive, aai->aai_ndisks);
                error = EINVAL;
                goto out;
        }

        adi = &aai->aai_disks[drive];
        adi->adi_dev = dksc->sc_dev;
        adi->adi_status = ADI_S_ONLINE | ADI_S_ASSIGNED;
        adi->adi_sectors = aai->aai_capacity;
        adi->adi_compsize = info->disk_sectors;

        error = 0;

 out:
        kmem_free(info, sizeof(*info));
        return (error);
}