VBLADE/vblade-master/ata.c

   1 // ata.c:  ATA simulator for vblade
   2 #include "config.h"
   3 #include <string.h>
   4 #include <stdio.h>
   5 #include <sys/types.h>
   6 #include "dat.h"
   7 #include "fns.h"
   8
   9 enum {
  10         // err bits
  11         UNC =   1<<6,
  12         MC =    1<<5,
  13         IDNF =  1<<4,
  14         MCR =   1<<3,
  15         ABRT =  1<<2,
  16         NM =    1<<1,
  17
  18         // status bits
  19         BSY =   1<<7,
  20         DRDY =  1<<6,
  21         DF =    1<<5,
  22         DRQ =   1<<3,
  23         ERR =   1<<0,
  24 };
  25
  26 static ushort ident[256];
  27
  28 static void
  29 setfld(ushort *a, int idx, int len, char *str)  // set field in ident
  30 {
  31         uchar *p;
  32
  33         p = (uchar *)(a+idx);
  34         while (len > 0) {
  35                 if (*str == 0)
  36                         p[1] = ' ';
  37                 else
  38                         p[1] = *str++;
  39                 if (*str == 0)
  40                         p[0] = ' ';
  41                 else
  42                         p[0] = *str++;
  43                 p += 2;
  44                 len -= 2;
  45         }
  46 }
  47
  48 static void
  49 setlba28(ushort *ident, vlong lba)
  50 {
  51         uchar *cp;
  52
  53         cp = (uchar *) &ident[60];
  54         *cp++ = lba;
  55         *cp++ = lba >>= 8;
  56         *cp++ = lba >>= 8;
  57         *cp++ = (lba >>= 8) & 0xf;
  58 }
  59
  60 static void
  61 setlba48(ushort *ident, vlong lba)
  62 {
  63         uchar *cp;
  64
  65         cp = (uchar *) &ident[100];
  66         *cp++ = lba;
  67         *cp++ = lba >>= 8;
  68         *cp++ = lba >>= 8;
  69         *cp++ = lba >>= 8;
  70         *cp++ = lba >>= 8;
  71         *cp++ = lba >>= 8;
  72 }
  73
  74 static void
  75 setushort(ushort *a, int i, ushort n)
  76 {
  77         uchar *p;
  78
  79         p = (uchar *)(a+i);
  80         *p++ = n & 0xff;
  81         *p++ = n >> 8;
  82 }
  83
  84 void
  85 atainit(void)
  86 {
  87         char buf[64];
  88
  89         setushort(ident, 47, 0x8000);
  90         setushort(ident, 49, 0x0200);
  91         setushort(ident, 50, 0x4000);
  92         setushort(ident, 83, 0x5400);
  93         setushort(ident, 84, 0x4000);
  94         setushort(ident, 86, 0x1400);
  95         setushort(ident, 87, 0x4000);
  96         setushort(ident, 93, 0x400b);
  97         setfld(ident, 27, 40, "Coraid EtherDrive vblade");
  98         sprintf(buf, "V%d", VBLADE_VERSION);
  99         setfld(ident, 23, 8, buf);
 100         setfld(ident, 10, 20, serial);
 101 }
 102
 103
 104 /* The ATA spec is weird in that you specify the device size as number
 105  * of sectors and then address the sectors with an offset.  That means
 106  * with LBA 28 you shouldn't see an LBA of all ones.  Still, we don't
 107  * check for that.
 108  */
 109 int
 110 atacmd(Ataregs *p, uchar *dp, int ndp, int payload) // do the ata cmd
 111 {
 112         vlong lba;
 113         ushort *ip;
 114         int n;
 115         enum { MAXLBA28SIZE = 0x0fffffff };
 116         extern int maxscnt;
 117
 118         p->status = 0;
 119         switch (p->cmd) {
 120         default:
 121                 p->status = DRDY | ERR;
 122                 p->err = ABRT;
 123                 return 0;
 124         case 0xe7:              // flush cache
 125                 return 0;
 126         case 0xec:              // identify device
 127                 if (p->sectors != 1 || ndp < 512)
 128                         return -1;
 129                 memmove(dp, ident, 512);
 130                 ip = (ushort *)dp;
 131                 if (size & ~MAXLBA28SIZE)
 132                         setlba28(ip, MAXLBA28SIZE);
 133                 else
 134                         setlba28(ip, size);
 135                 setlba48(ip, size);
 136                 p->err = 0;
 137                 p->status = DRDY;
 138                 p->sectors = 0;
 139                 return 0;
 140         case 0xe5:              // check power mode
 141                 p->err = 0;
 142                 p->sectors = 0xff; // the device is active or idle
 143                 p->status = DRDY;
 144                 return 0;
 145         case 0x20:              // read sectors
 146         case 0x30:              // write sectors
 147                 lba = p->lba & MAXLBA28SIZE;
 148                 break;
 149         case 0x24:              // read sectors ext
 150         case 0x34:              // write sectors ext
 151                 lba = p->lba & 0x0000ffffffffffffLL;    // full 48
 152                 break;
 153         }
 154
 155         // we ought not be here unless we are a read/write
 156
 157         if (p->sectors > maxscnt || p->sectors*512 > ndp)
 158                 return -1;
 159
 160         if (lba + p->sectors > size) {
 161                 p->err = IDNF;
 162                 p->status = DRDY | ERR;
 163                 p->lba = lba;
 164                 return 0;
 165         }
 166         if (p->cmd == 0x20 || p->cmd == 0x24)
 167                 n = getsec(bfd, dp, lba+offset, p->sectors);
 168         else {
 169                 // packet should be big enough to contain the data
 170                 if (payload < 512 * p->sectors)
 171                         return -1;
 172                 n = putsec(bfd, dp, lba+offset, p->sectors);
 173         }
 174         n /= 512;
 175         if (n != p->sectors) {
 176                 p->err = ABRT;
 177                 p->status = ERR;
 178         } else
 179                 p->err = 0;
 180         p->status |= DRDY;
 181         p->lba += n;
 182         p->sectors -= n;
 183         return 0;
 184 }
 185