eepro100: Add missing SCB register names

Some system control block registers were addressed
using their offset value. Use symbolic names now
and clean the documentation.
Signed-off-by: NStefan Weil <weil@mail.berlios.de>
Signed-off-by: NMichael S. Tsirkin <mst@redhat.com>

hw/eepro100.c

@@ -125,16 +125,20 @@
 /* Offsets to the various registers.
    All accesses need not be longword aligned. */
 enum speedo_offsets {
-    SCBStatus = 0,
+    SCBStatus = 0,              /* Status Word. */
     SCBAck = 1,
     SCBCmd = 2,                 /* Rx/Command Unit command and status. */
     SCBIntmask = 3,
     SCBPointer = 4,             /* General purpose pointer. */
     SCBPort = 8,                /* Misc. commands and operands.  */
-    SCBflash = 12, SCBeeprom = 14,      /* EEPROM and flash memory control. */
+    SCBflash = 12,              /* Flash memory control. */
+    SCBeeprom = 14,             /* EEPROM control. */
     SCBCtrlMDI = 16,            /* MDI interface control. */
     SCBEarlyRx = 20,            /* Early receive byte count. */
-    SCBFlow = 24,
+    SCBFlow = 24,               /* Flow Control. */
+    SCBpmdr = 27,               /* Power Management Driver. */
+    SCBgctrl = 28,              /* General Control. */
+    SCBgstat = 29,              /* General Status. */
 };
 
 /* A speedo3 transmit buffer descriptor with two buffers... */
@@ -1333,11 +1337,11 @@ static uint8_t eepro100_read1(EEPRO100State * s, uint32_t addr)
     case SCBeeprom:
         val = eepro100_read_eeprom(s);
         break;
-    case 0x1b:                 /* PMDR (power management driver register) */
+    case SCBpmdr:       /* Power Management Driver Register */
         val = 0;
         TRACE(OTHER, logout("addr=%s val=0x%02x\n", regname(addr), val));
         break;
-    case 0x1d:                 /* general status register */
+    case SCBgstat:      /* General Status Register */
         /* 100 Mbps full duplex, valid link */
         val = 0x07;
         TRACE(OTHER, logout("addr=General Status val=%02x\n", val));
@@ -1431,7 +1435,7 @@ static void eepro100_write1(EEPRO100State * s, uint32_t addr, uint8_t val)
     case SCBFlow:       /* does not exist on 82557 */
     case SCBFlow + 1:
     case SCBFlow + 2:
-    case SCBFlow + 3:
+    case SCBpmdr:       /* does not exist on 82557 */
         TRACE(OTHER, logout("addr=%s val=0x%02x\n", regname(addr), val));
         break;
     case SCBeeprom: