?? seagate.c
字號:
return 0;
}
int seagate_st0x_command (Scsi_Cmnd * SCpnt) {
return internal_command (SCpnt->target, SCpnt->lun, SCpnt->cmnd, SCpnt->request_buffer,
SCpnt->request_bufflen,
(int) NO_RECONNECT);
}
static int internal_command(unsigned char target, unsigned char lun, const void *cmnd,
void *buff, int bufflen, int reselect) {
int len = 0;
unsigned char *data = NULL;
struct scatterlist *buffer = NULL;
int nobuffs = 0;
int clock;
int temp;
#ifdef SLOW_HANDSHAKE
int borken; /* Does the current target require Very Slow I/O ? */
#endif
#if (DEBUG & PHASE_DATAIN) || (DEBUG & PHASE_DATOUT)
int transfered = 0;
#endif
#if (((DEBUG & PHASE_ETC) == PHASE_ETC) || (DEBUG & PRINT_COMMAND) || \
(DEBUG & PHASE_EXIT))
int i;
#endif
#if ((DEBUG & PHASE_ETC) == PHASE_ETC)
int phase=0, newphase;
#endif
int done = 0;
unsigned char status = 0;
unsigned char message = 0;
register unsigned char status_read;
unsigned transfersize = 0, underflow = 0;
incommand = 0;
st0x_aborted = 0;
#ifdef SLOW_HANDSHAKE
borken = (int) scsi_devices[SCint->index].borken;
#endif
#if (DEBUG & PRINT_COMMAND)
printk ("scsi%d : target = %d, command = ", hostno, target);
print_command((unsigned char *) cmnd);
printk("\n");
#endif
#if (DEBUG & PHASE_RESELECT)
switch (reselect) {
case RECONNECT_NOW :
printk("scsi%d : reconnecting\n", hostno);
break;
#ifdef LINKED
case LINKED_RIGHT :
printk("scsi%d : connected, can reconnect\n", hostno);
break;
case LINKED_WRONG :
printk("scsi%d : connected to wrong target, can reconnect\n",
hostno);
break;
#endif
case CAN_RECONNECT :
printk("scsi%d : allowed to reconnect\n", hostno);
break;
default :
printk("scsi%d : not allowed to reconnect\n", hostno);
}
#endif
if (target == (controller_type == SEAGATE ? 7 : 6))
return DID_BAD_TARGET;
/*
* We work it differently depending on if this is is "the first time,"
* or a reconnect. If this is a reselct phase, then SEL will
* be asserted, and we must skip selection / arbitration phases.
*/
switch (reselect) {
case RECONNECT_NOW:
#if (DEBUG & PHASE_RESELECT)
printk("scsi%d : phase RESELECT \n", hostno);
#endif
/*
* At this point, we should find the logical or of our ID and the original
* target's ID on the BUS, with BSY, SEL, and I/O signals asserted.
*
* After ARBITRATION phase is completed, only SEL, BSY, and the
* target ID are asserted. A valid initator ID is not on the bus
* until IO is asserted, so we must wait for that.
*/
for (clock = jiffies + 10, temp = 0; (jiffies < clock) &&
!(STATUS & STAT_IO););
if (jiffies >= clock)
{
#if (DEBUG & PHASE_RESELECT)
printk("scsi%d : RESELECT timed out while waiting for IO .\n",
hostno);
#endif
return (DID_BAD_INTR << 16);
}
/*
* After I/O is asserted by the target, we can read our ID and its
* ID off of the BUS.
*/
if (!((temp = DATA) & (controller_type == SEAGATE ? 0x80 : 0x40)))
{
#if (DEBUG & PHASE_RESELECT)
printk("scsi%d : detected reconnect request to different target.\n"
"\tData bus = %d\n", hostno, temp);
#endif
return (DID_BAD_INTR << 16);
}
if (!(temp & (1 << current_target)))
{
printk("scsi%d : Unexpected reselect interrupt. Data bus = %d\n",
hostno, temp);
return (DID_BAD_INTR << 16);
}
buffer=current_buffer;
cmnd=current_cmnd; /* WDE add */
data=current_data; /* WDE add */
len=current_bufflen; /* WDE add */
nobuffs=current_nobuffs;
/*
* We have determined that we have been selected. At this point,
* we must respond to the reselection by asserting BSY ourselves
*/
#if 1
CONTROL = (BASE_CMD | CMD_DRVR_ENABLE | CMD_BSY);
#else
CONTROL = (BASE_CMD | CMD_BSY);
#endif
/*
* The target will drop SEL, and raise BSY, at which time we must drop
* BSY.
*/
for (clock = jiffies + 10; (jiffies < clock) && (STATUS & STAT_SEL););
if (jiffies >= clock)
{
CONTROL = (BASE_CMD | CMD_INTR);
#if (DEBUG & PHASE_RESELECT)
printk("scsi%d : RESELECT timed out while waiting for SEL.\n",
hostno);
#endif
return (DID_BAD_INTR << 16);
}
CONTROL = BASE_CMD;
/*
* At this point, we have connected with the target and can get
* on with our lives.
*/
break;
case CAN_RECONNECT:
#ifdef LINKED
/*
* This is a bletcherous hack, just as bad as the Unix #! interpreter stuff.
* If it turns out we are using the wrong I_T_L nexus, the easiest way to deal
* with it is to go into our INFORMATION TRANSFER PHASE code, send a ABORT
* message on MESSAGE OUT phase, and then loop back to here.
*/
connect_loop :
#endif
#if (DEBUG & PHASE_BUS_FREE)
printk ("scsi%d : phase = BUS FREE \n", hostno);
#endif
/*
* BUS FREE PHASE
*
* On entry, we make sure that the BUS is in a BUS FREE
* phase, by insuring that both BSY and SEL are low for
* at least one bus settle delay. Several reads help
* eliminate wire glitch.
*/
clock = jiffies + ST0X_BUS_FREE_DELAY;
#if !defined (ARBITRATE)
while (((STATUS | STATUS | STATUS) &
(STAT_BSY | STAT_SEL)) &&
(!st0x_aborted) && (jiffies < clock));
if (jiffies > clock)
return retcode(DID_BUS_BUSY);
else if (st0x_aborted)
return retcode(st0x_aborted);
#endif
#if (DEBUG & PHASE_SELECTION)
printk("scsi%d : phase = SELECTION\n", hostno);
#endif
clock = jiffies + ST0X_SELECTION_DELAY;
/*
* Arbitration/selection procedure :
* 1. Disable drivers
* 2. Write HOST adapter address bit
* 3. Set start arbitration.
* 4. We get either ARBITRATION COMPLETE or SELECT at this
* point.
* 5. OR our ID and targets on bus.
* 6. Enable SCSI drivers and asserted SEL and ATTN
*/
#if defined(ARBITRATE)
cli();
CONTROL = 0;
DATA = (controller_type == SEAGATE) ? 0x80 : 0x40;
CONTROL = CMD_START_ARB;
sti();
while (!((status_read = STATUS) & (STAT_ARB_CMPL | STAT_SEL)) &&
(jiffies < clock) && !st0x_aborted);
if (!(status_read & STAT_ARB_CMPL)) {
#if (DEBUG & PHASE_SELECTION)
if (status_read & STAT_SEL)
printk("scsi%d : arbitration lost\n", hostno);
else
printk("scsi%d : arbitration timeout.\n", hostno);
#endif
CONTROL = BASE_CMD;
return retcode(DID_NO_CONNECT);
};
#if (DEBUG & PHASE_SELECTION)
printk("scsi%d : arbitration complete\n", hostno);
#endif
#endif
/*
* When the SCSI device decides that we're gawking at it, it will
* respond by asserting BUSY on the bus.
*
* Note : the Seagate ST-01/02 product manual says that we should
* twiddle the DATA register before the control register. However,
* this does not work reliably so we do it the other way arround.
*
* Probably could be a problem with arbitration too, we really should
* try this with a SCSI protocol or logic analyzer to see what is
* going on.
*/
cli();
DATA = (unsigned char) ((1 << target) | (controller_type == SEAGATE ? 0x80 : 0x40));
CONTROL = BASE_CMD | CMD_DRVR_ENABLE | CMD_SEL |
(reselect ? CMD_ATTN : 0);
sti();
while (!((status_read = STATUS) & STAT_BSY) &&
(jiffies < clock) && !st0x_aborted)
#if 0 && (DEBUG & PHASE_SELECTION)
{
temp = clock - jiffies;
if (!(jiffies % 5))
printk("seagate_st0x_timeout : %d \r",temp);
}
printk("Done. \n");
printk("scsi%d : status = %02x, seagate_st0x_timeout = %d, aborted = %02x \n",
hostno, status_read, temp, st0x_aborted);
#else
;
#endif
if ((jiffies >= clock) && !(status_read & STAT_BSY))
{
#if (DEBUG & PHASE_SELECTION)
printk ("scsi%d : NO CONNECT with target %d, status = %x \n",
hostno, target, STATUS);
#endif
return retcode(DID_NO_CONNECT);
}
/*
* If we have been aborted, and we have a command in progress, IE the
* target still has BSY asserted, then we will reset the bus, and
* notify the midlevel driver to expect sense.
*/
if (st0x_aborted) {
CONTROL = BASE_CMD;
if (STATUS & STAT_BSY) {
printk("scsi%d : BST asserted after we've been aborted.\n",
hostno);
seagate_st0x_reset(NULL);
return retcode(DID_RESET);
}
return retcode(st0x_aborted);
}
/* Establish current pointers. Take into account scatter / gather */
if ((nobuffs = SCint->use_sg)) {
#if (DEBUG & DEBUG_SG)
{
int i;
printk("scsi%d : scatter gather requested, using %d buffers.\n",
hostno, nobuffs);
for (i = 0; i < nobuffs; ++i)
printk("scsi%d : buffer %d address = %08x length = %d\n",
hostno, i, buffer[i].address, buffer[i].length);
}
#endif
buffer = (struct scatterlist *) SCint->buffer;
len = buffer->length;
data = (unsigned char *) buffer->address;
} else {
#if (DEBUG & DEBUG_SG)
printk("scsi%d : scatter gather not requested.\n", hostno);
#endif
buffer = NULL;
len = SCint->request_bufflen;
data = (unsigned char *) SCint->request_buffer;
}
#if (DEBUG & (PHASE_DATAIN | PHASE_DATAOUT))
printk("scsi%d : len = %d\n", hostno, len);
#endif
break;
#ifdef LINKED
case LINKED_RIGHT:
break;
case LINKED_WRONG:
break;
#endif
}
/*
* There are several conditions under which we wish to send a message :
* 1. When we are allowing disconnect / reconnect, and need to establish
* the I_T_L nexus via an IDENTIFY with the DiscPriv bit set.
*
* 2. When we are doing linked commands, are have the wrong I_T_L nexus
* established and want to send an ABORT message.
*/
CONTROL = BASE_CMD | CMD_DRVR_ENABLE |
(((reselect == CAN_RECONNECT)
#ifdef LINKED
|| (reselect == LINKED_WRONG)
#endif
) ? CMD_ATTN : 0) ;
/*
* INFORMATION TRANSFER PHASE
*
* The nasty looking read / write inline assembler loops we use for
* DATAIN and DATAOUT phases are approximately 4-5 times as fast as
* the 'C' versions - since we're moving 1024 bytes of data, this
* really adds up.
*/
#if ((DEBUG & PHASE_ETC) == PHASE_ETC)
printk("scsi%d : phase = INFORMATION TRANSFER\n", hostno);
#endif
incommand = 1;
transfersize = SCint->transfersize;
underflow = SCint->underflow;
/*
* Now, we poll the device for status information,
* and handle any requests it makes. Note that since we are unsure of
* how much data will be flowing across the system, etc and cannot
* make reasonable timeouts, that we will instead have the midlevel
* driver handle any timeouts that occur in this phase.
*/
while (((status_read = STATUS) & STAT_BSY) && !st0x_aborted && !done)
{
#ifdef PARITY
if (status_read & STAT_PARITY)
{
printk("scsi%d : got parity error\n", hostno);
st0x_aborted = DID_PARITY;
}
#endif
if (status_read & STAT_REQ)
{
#if ((DEBUG & PHASE_ETC) == PHASE_ETC)
if ((newphase = (status_read & REQ_MASK)) != phase)
{
phase = newphase;
switch (phase)
{
case REQ_DATAOUT:
printk("scsi%d : phase = DATA OUT\n",
hostno);
break;
case REQ_DATAIN :
printk("scsi%d : phase = DATA IN\n",
hostno);
break;
case REQ_CMDOUT :
printk("scsi%d : phase = COMMAND OUT\n",
hostno);
break;
case REQ_STATIN :
printk("scsi%d : phase = STATUS IN\n",
hostno);
break;
case REQ_MSGOUT :
printk("scsi%d : phase = MESSAGE OUT\n",
hostno);
break;
case REQ_MSGIN :
printk("scsi%d : phase = MESSAGE IN\n",
hostno);
break;
default :
printk("scsi%d : phase = UNKNOWN\n",
hostno);
st0x_aborted = DID_ERROR;
}
}
#endif
switch (status_read & REQ_MASK)
{
case REQ_DATAOUT :
/*
* If we are in fast mode, then we simply splat the data out
* in word-sized chunks as fast as we can.
*/
#ifdef FAST
if (!len) {
#if 0
printk("scsi%d: underflow to target %d lun %d \n",
hostno, target, lun);
st0x_aborted = DID_ERROR;
fast = 0;
#endif
break;
}
if (fast && transfersize && !(len % transfersize) && (len >= transfersize)
#ifdef FAST32
&& !(transfersize % 4)
#endif
) {
#if (DEBUG & DEBUG_FAST)
printk("scsi%d : FAST transfer, underflow = %d, transfersize = %d\n"
" len = %d, data = %08x\n", hostno, SCint->underflow,
SCint->transfersize, len, data);
#endif
__asm__("
cld;
"
#ifdef FAST32
" shr $2, %%ecx;
1: lodsl;
movl %%eax, (%%edi);
"
#else
"1: lodsb;
movb %%al, (%%edi);
"
#endif
" loop 1b;" : :
/* input */
"D" (st0x_dr), "S" (data), "c" (SCint->transfersize) :
/* clobbered */
"eax", "ecx", "esi" );
len -= transfersize;
data += transfersize;
#if (DEBUG & DEBUG_FAST)
printk("scsi%d : FAST transfer complete len = %d data = %08x\n",
hostno, len, data);
#endif
} else
#endif
{
/*
* We loop as long as we are in a data out phase, there is data to send,
* and BSY is still active.
*/
__asm__ (
/*
Local variables :
len = ecx
data = esi
st0x_cr_sr = ebx
st0x_dr = edi
Test for any data here at all.
*/
"\torl %%ecx, %%ecx
jz 2f
cld
movl _st0x_cr_sr, %%ebx
movl _st0x_dr, %%edi
1: movb (%%ebx), %%al\n"
/*
Test for BSY
*/
"\ttest $1, %%al
jz 2f\n"
/*
Test for data out phase - STATUS & REQ_MASK should be REQ_DATAOUT, which is 0.
*/
"\ttest $0xe, %%al
jnz 2f \n"
/*
Test for REQ
*/
"\ttest $0x10, %%al
jz 1b
lodsb
movb %%al, (%%edi)
loop 1b
2:
":
/* output */
"=S" (data), "=c" (len) :
/* input */
"0" (data), "1" (len) :
/* clobbered */
"eax", "ebx", "edi");
}
if (!len && nobuffs) {
--nobuffs;
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