493 lines
14 KiB
Groff
493 lines
14 KiB
Groff
.\" Copyright (c) 1998, 1999, Nicolas Souchu
|
|
.\" 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.
|
|
.\" 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.
|
|
.\"
|
|
.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``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 OR CONTRIBUTORS 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.
|
|
.\"
|
|
.\" $FreeBSD$
|
|
.\"
|
|
.Dd June 6, 1998
|
|
.Dt MICROSEQ 9
|
|
.Os FreeBSD
|
|
.Sh NAME
|
|
.Nm microseq
|
|
.Nd
|
|
ppbus microseqencer developer's guide
|
|
.Sh SYNOPSIS
|
|
.Fd "#include <sys/types.h>"
|
|
.Fd "#include <dev/ppbus/ppbconf.h>"
|
|
.Fd "#include <dev/ppbus/ppb_msq.h>"
|
|
.Sh DESCRIPTION
|
|
See
|
|
.Xr ppbus 4
|
|
for ppbus description and general info about the microsequencer.
|
|
.Pp
|
|
The purpose of this document is to encourage developers to use the
|
|
microsequencer mechanism in order to have:
|
|
.Bl -enum -offset indent
|
|
.It
|
|
a uniform programming model
|
|
.It
|
|
efficient code
|
|
.El
|
|
.Pp
|
|
Before using microsequences, you are encouraged to look at
|
|
.Xr ppc 4
|
|
microsequencer implementation and an example of how using it in
|
|
.Xr vpo 4 .
|
|
.Sh PPBUS register model
|
|
.Ss Background
|
|
The parallel port model chosen for ppbus is the PC parallel port model.
|
|
Thus, any register described later has the same semantic than its counterpart
|
|
in a PC parallel port.
|
|
For more info about ISA/ECP programming, get the
|
|
Microsoft standard referenced as "Extended Capabilities Port Protocol and
|
|
ISA interface Standard". Registers described later are standard parallel port
|
|
registers.
|
|
.Pp
|
|
Mask macros are defined in the standard ppbus include files for each valid
|
|
bit of parallel port registers.
|
|
.Ss Data register
|
|
In compatible or nibble mode, writing to this register will drive data to the
|
|
parallel port data lines.
|
|
In any other mode, drivers may be tri-stated by
|
|
setting the direction bit (PCD) in the control register.
|
|
Reads to this register
|
|
return the value on the data lines.
|
|
.Ss Device status register
|
|
This read-only register reflects the inputs on the parallel port interface.
|
|
.Pp
|
|
.Bl -column "Bit" "Name" "Description" -compact
|
|
.It Em Bit Ta Em Name Ta Em Description
|
|
.It 7 Ta nBUSY Ta "inverted version of parallel port Busy signal"
|
|
.It 6 Ta nACK Ta "version of parallel port nAck signal"
|
|
.It 5 Ta PERROR Ta "version of parallel port PERROR signal"
|
|
.It 4 Ta SELECT Ta "version of parallel port Select signal"
|
|
.It 3 Ta nFAULT Ta "version of parallel port nFault signal"
|
|
.El
|
|
.Pp
|
|
Others are reserved and return undefined result when read.
|
|
.Ss Device control register
|
|
This register directly controls several output signals as well as enabling
|
|
some functions.
|
|
.Pp
|
|
.Bl -column "Bit" "Name " "Description" -compact
|
|
.It Em Bit Ta Em Name Ta Em Description
|
|
.It 5 Ta PCD Ta "direction bit in extended modes"
|
|
.It 4 Ta IRQENABLE Ta "1 enables an interrupt on the rising edge of nAck"
|
|
.It 3 Ta SELECTIN Ta "inverted and driven as parallel port nSelectin signal"
|
|
.It 2 Ta nINIT Ta "driven as parallel port nInit signal"
|
|
.It 1 Ta AUTOFEED Ta "inverted and driven as parallel port nAutoFd signal"
|
|
.It 0 Ta STROBE Ta "inverted and driven as parallel port nStrobe signal"
|
|
.El
|
|
.Sh MICROINSTRUCTIONS
|
|
.Ss Description
|
|
.Em Microinstructions
|
|
are either parallel port accesses, program iterations, submicrosequence or
|
|
C calls.
|
|
The parallel port must be considered as the logical model described in
|
|
.Xr ppbus 4 .
|
|
.Pp
|
|
Available microinstructions are:
|
|
.Bd -literal
|
|
#define MS_OP_GET 0 /* get <ptr>, <len> */
|
|
#define MS_OP_PUT 1 /* put <ptr>, <len> */
|
|
#define MS_OP_RFETCH 2 /* rfetch <reg>, <mask>, <ptr> */
|
|
#define MS_OP_RSET 3 /* rset <reg>, <mask>, <mask> */
|
|
#define MS_OP_RASSERT 4 /* rassert <reg>, <mask> */
|
|
#define MS_OP_DELAY 5 /* delay <val> */
|
|
#define MS_OP_SET 6 /* set <val> */
|
|
#define MS_OP_DBRA 7 /* dbra <offset> */
|
|
#define MS_OP_BRSET 8 /* brset <mask>, <offset> */
|
|
#define MS_OP_BRCLEAR 9 /* brclear <mask>, <offset> */
|
|
#define MS_OP_RET 10 /* ret <retcode> */
|
|
#define MS_OP_C_CALL 11 /* c_call <function>, <parameter> */
|
|
#define MS_OP_PTR 12 /* ptr <pointer> */
|
|
#define MS_OP_ADELAY 13 /* adelay <val> */
|
|
#define MS_OP_BRSTAT 14 /* brstat <mask>, <mask>, <offset> */
|
|
#define MS_OP_SUBRET 15 /* subret <code> */
|
|
#define MS_OP_CALL 16 /* call <microsequence> */
|
|
#define MS_OP_RASSERT_P 17 /* rassert_p <iter>, <reg> */
|
|
#define MS_OP_RFETCH_P 18 /* rfetch_p <iter>, <reg>, <mask> */
|
|
#define MS_OP_TRIG 19 /* trigger <reg>, <len>, <array> */
|
|
.Ed
|
|
.Ss Execution context
|
|
The
|
|
.Em execution context
|
|
of microinstructions is:
|
|
.Bl -bullet -item -offset indent
|
|
.It
|
|
the
|
|
.Em program counter
|
|
which points to the next microinstruction to execute either in the main
|
|
microsequence or in a subcall
|
|
.It
|
|
the current value of
|
|
.Em ptr
|
|
which points to the next char to send/receive
|
|
.It
|
|
the current value of the internal
|
|
.Em branch register
|
|
.El
|
|
.Pp
|
|
This data is modified by some of the microinstructions, not all.
|
|
.Ss MS_OP_GET and MS_OP_PUT
|
|
are microinstructions used to do either predefined standard IEEE1284-1994
|
|
transfers or programmed non-standard io.
|
|
.Ss MS_OP_RFETCH - Register FETCH
|
|
is used to retrieve the current value of a parallel port register, apply a
|
|
mask and save it in a buffer.
|
|
.Pp
|
|
Parameters:
|
|
.Bl -enum -offset indent
|
|
.It
|
|
register
|
|
.It
|
|
character mask
|
|
.It
|
|
pointer to the buffer
|
|
.El
|
|
.Pp
|
|
Predefined macro: MS_RFETCH(reg,mask,ptr)
|
|
.Ss MS_OP_RSET - Register SET
|
|
is used to assert/clear some bits of a particular parallel port register,
|
|
two masks are applied.
|
|
.Pp
|
|
Parameters:
|
|
.Bl -enum -offset ident
|
|
.It
|
|
register
|
|
.It
|
|
mask of bits to assert
|
|
.It
|
|
mask of bits to clear
|
|
.El
|
|
.Pp
|
|
Predefined macro: MS_RSET(reg,assert,clear)
|
|
.Ss MS_OP_RASSERT - Register ASSERT
|
|
is used to assert all bits of a particular parallel port register.
|
|
.Pp
|
|
Parameters:
|
|
.Bl -enum -offset ident
|
|
.It
|
|
register
|
|
.It
|
|
byte to assert
|
|
.El
|
|
.Pp
|
|
Predefined macro: MS_RASSERT(reg,byte)
|
|
.Ss MS_OP_DELAY - microsecond DELAY
|
|
is used to delay the execution of the microsequence.
|
|
.Pp
|
|
Parameter:
|
|
.Bl -enum -offset ident
|
|
.It
|
|
delay in microseconds
|
|
.El
|
|
.Pp
|
|
Predefined macro: MS_DELAY(delay)
|
|
.Ss MS_OP_SET - SET internal branch register
|
|
is used to set the value of the internal branch register.
|
|
.Pp
|
|
Parameter:
|
|
.Bl -enum -offset ident
|
|
.It
|
|
integer value
|
|
.El
|
|
.Pp
|
|
Predefined macro: MS_SET(accum)
|
|
.Ss MS_OP_DBRA - Do BRAnch
|
|
is used to branch if internal branch register decremented by one result value
|
|
is positive.
|
|
.Pp
|
|
Parameter:
|
|
.Bl -enum -offset ident
|
|
.It
|
|
integer offset in the current executed (sub)microsequence.
|
|
Offset is added to
|
|
the index of the next microinstruction to execute.
|
|
.El
|
|
.Pp
|
|
Predefined macro: MS_DBRA(offset)
|
|
.Ss MS_OP_BRSET - BRanch on SET
|
|
is used to branch if some of the status register bits of the parallel port
|
|
are set.
|
|
.Pp
|
|
Parameter:
|
|
.Bl -enum -offset ident
|
|
.It
|
|
bits of the status register
|
|
.It
|
|
integer offset in the current executed (sub)microsequence.
|
|
Offset is added to
|
|
the index of the next microinstruction to execute.
|
|
.El
|
|
.Pp
|
|
Predefined macro: MS_BRSET(mask,offset)
|
|
.Ss MS_OP_BRCLEAR - BRanch on CLEAR
|
|
is used to branch if some of the status register bits of the parallel port
|
|
are cleared.
|
|
.Pp
|
|
Parameter:
|
|
.Bl -enum -offset ident
|
|
.It
|
|
bits of the status register
|
|
.It
|
|
integer offset in the current executed (sub)microsequence.
|
|
Offset is added to
|
|
the index of the next microinstruction to execute.
|
|
.El
|
|
.Pp
|
|
Predefined macro: MS_BRCLEAR(mask,offset)
|
|
.Ss MS_OP_RET - RETurn
|
|
is used to return from a microsequence.
|
|
This instruction is mandatory.
|
|
This
|
|
is the only way for the microsequencer to detect the end of the microsequence.
|
|
The return code is returned in the integer pointed by the (int *) parameter
|
|
of the ppb_MS_microseq().
|
|
.Pp
|
|
Parameter:
|
|
.Bl -enum -offset ident
|
|
.It
|
|
integer return code
|
|
.El
|
|
.Pp
|
|
Predefined macro: MS_RET(code)
|
|
.Ss MS_OP_C_CALL - C function CALL
|
|
is used to call C functions from microsequence execution.
|
|
This may be useful
|
|
when a non-standard i/o is performed to retrieve a data character from the
|
|
parallel port.
|
|
.Pp
|
|
Parameter:
|
|
.Bl -enum -offset ident
|
|
.It
|
|
the C function to call
|
|
.It
|
|
the parameter to pass to the function call
|
|
.El
|
|
.Pp
|
|
The C function shall be declared as a
|
|
.Fd int(*)(void *p, char *ptr)
|
|
The ptr parameter is the current position in the buffer currently scanned.
|
|
.Pp
|
|
Predefined macro: MS_C_CALL(func,param)
|
|
.Ss MS_OP_PTR - initialize internal PTR
|
|
is used to initialize the internal pointer to the currently scanned buffer.
|
|
This pointer is passed to any C call (see above).
|
|
.Pp
|
|
Parameter:
|
|
.Bl -enum -offset ident
|
|
.It
|
|
pointer to the buffer that shall be accessed by xxx_P() microsequence calls.
|
|
Note that this pointer is automatically incremented during xxx_P() calls
|
|
.El
|
|
.Pp
|
|
Predefined macro: MS_PTR(ptr)
|
|
.Ss MS_OP_ADELAY - do an Asynchronous DELAY
|
|
is used to make a tsleep() during microsequence execution.
|
|
The tsleep is
|
|
executed at PPBPRI level.
|
|
.Pp
|
|
Parameter:
|
|
.Bl -enum -offset ident
|
|
.It
|
|
delay in ms
|
|
.El
|
|
.Pp
|
|
Predefined macro: MS_ADELAY(delay)
|
|
.Ss MS_OP_BRSTAT - BRanch on STATe
|
|
is used to branch on status register state condition.
|
|
.Pp
|
|
Parameter:
|
|
.Bl -enum -offset ident
|
|
.It
|
|
mask of asserted bits.
|
|
Bits that shall be asserted in the status register
|
|
are set in the mask
|
|
.It
|
|
mask of cleared bits.
|
|
Bits that shall be cleared in the status register
|
|
are set in the mask
|
|
.It
|
|
integer offset in the current executed (sub)microsequence.
|
|
Offset is added
|
|
to the index of the next microinstruction to execute.
|
|
.El
|
|
.Pp
|
|
Predefined macro: MS_BRSTAT(asserted_bits,clear_bits,offset)
|
|
.Ss MS_OP_SUBRET - SUBmicrosequence RETurn
|
|
is used to return from the submicrosequence call.
|
|
This action is mandatory
|
|
before a RET call.
|
|
Some microinstructions (PUT, GET) may not be callable
|
|
within a submicrosequence.
|
|
.Pp
|
|
No parameter.
|
|
.Pp
|
|
Predefined macro: MS_SUBRET()
|
|
.Ss MS_OP_CALL - submicrosequence CALL
|
|
is used to call a submicrosequence.
|
|
A submicrosequence is a microsequence with
|
|
a SUBRET call.
|
|
Parameter:
|
|
.Bl -enum -offset ident
|
|
.It
|
|
the submicrosequence to execute
|
|
.El
|
|
.Pp
|
|
Predefined macro: MS_CALL(microseq)
|
|
.Ss MS_OP_RASSERT_P - Register ASSERT from internal PTR
|
|
is used to assert a register with data currently pointed by the internal PTR
|
|
pointer.
|
|
Parameter:
|
|
.Bl -enum -offset ident
|
|
.It
|
|
amount of data to write to the register
|
|
.It
|
|
register
|
|
.El
|
|
.Pp
|
|
Predefined macro: MS_RASSERT_P(iter,reg)
|
|
.Ss MS_OP_RFETCH_P - Register FETCH to internal PTR
|
|
is used to fetch data from a register.
|
|
Data is stored in the buffer currently
|
|
pointed by the internal PTR pointer.
|
|
Parameter:
|
|
.Bl -enum -offset ident
|
|
.It
|
|
amount of data to read from the register
|
|
.It
|
|
register
|
|
.It
|
|
mask applied to fetched data
|
|
.El
|
|
.Pp
|
|
Predefined macro: MS_RFETCH_P(iter,reg,mask)
|
|
.Ss MS_OP_TRIG - TRIG register
|
|
is used to trigger the parallel port.
|
|
This microinstruction is intended to
|
|
provide a very efficient control of the parallel port.
|
|
Triggering a register
|
|
is writing data, wait a while, write data, wait a while...
|
|
This allows to
|
|
write magic sequences to the port.
|
|
Parameter:
|
|
.Bl -enum -offset ident
|
|
.It
|
|
amount of data to read from the register
|
|
.It
|
|
register
|
|
.It
|
|
size of the array
|
|
.It
|
|
array of unsigned chars.
|
|
Each couple of u_chars define the data to write to
|
|
the register and the delay in us to wait.
|
|
The delay is limited to 255 us to
|
|
simplify and reduce the size of the array.
|
|
.El
|
|
.Pp
|
|
Predefined macro: MS_TRIG(reg,len,array)
|
|
.Sh MICROSEQUENCES
|
|
.Ss C structures
|
|
.Bd -literal
|
|
union ppb_insarg {
|
|
int i;
|
|
char c;
|
|
void *p;
|
|
int (* f)(void *, char *);
|
|
};
|
|
|
|
struct ppb_microseq {
|
|
int opcode; /* microins. opcode */
|
|
union ppb_insarg arg[PPB_MS_MAXARGS]; /* arguments */
|
|
};
|
|
.Ed
|
|
.Ss Using microsequences
|
|
To instantiate a microsequence, just declare an array of ppb_microseq
|
|
structures and initialize it as needed.
|
|
You may either use predefined macros
|
|
or code directly your microinstructions according to the ppb_microseq
|
|
definition.
|
|
For example,
|
|
.Bd -literal
|
|
struct ppb_microseq select_microseq[] = {
|
|
|
|
/* parameter list
|
|
*/
|
|
#define SELECT_TARGET MS_PARAM(0, 1, MS_TYP_INT)
|
|
#define SELECT_INITIATOR MS_PARAM(3, 1, MS_TYP_INT)
|
|
|
|
/* send the select command to the drive */
|
|
MS_DASS(MS_UNKNOWN),
|
|
MS_CASS(H_nAUTO | H_nSELIN | H_INIT | H_STROBE),
|
|
MS_CASS( H_AUTO | H_nSELIN | H_INIT | H_STROBE),
|
|
MS_DASS(MS_UNKNOWN),
|
|
MS_CASS( H_AUTO | H_nSELIN | H_nINIT | H_STROBE),
|
|
|
|
/* now, wait until the drive is ready */
|
|
MS_SET(VP0_SELTMO),
|
|
/* loop: */ MS_BRSET(H_ACK, 2 /* ready */),
|
|
MS_DBRA(-2 /* loop */),
|
|
/* error: */ MS_RET(1),
|
|
/* ready: */ MS_RET(0)
|
|
};
|
|
.Ed
|
|
.Pp
|
|
Here, some parameters are undefined and must be filled before executing
|
|
the microsequence.
|
|
In order to initialize each microsequence, one
|
|
should use the ppb_MS_init_msq() function like this:
|
|
.Bd -literal
|
|
ppb_MS_init_msq(select_microseq, 2,
|
|
SELECT_TARGET, 1 << target,
|
|
SELECT_INITIATOR, 1 << initiator);
|
|
.Ed
|
|
.Pp
|
|
and then execute the microsequence.
|
|
.Ss The microsequencer
|
|
The microsequencer is executed either at ppbus or adapter level (see
|
|
.Xr ppbus 4
|
|
for info about ppbus system layers). Most of the microsequencer is executed
|
|
at ppc level to avoid ppbus to adapter function call overhead.
|
|
But some
|
|
actions like deciding whereas the transfer is IEEE1284-1994 compliant are
|
|
executed at ppbus layer.
|
|
.Sh BUGS
|
|
Only one level of submicrosequences is allowed.
|
|
.Pp
|
|
When triggering the port, maximum delay allowed is 255 us.
|
|
.Sh SEE ALSO
|
|
.Xr ppbus 4 ,
|
|
.Xr ppc 4 ,
|
|
.Xr vpo 4
|
|
.Sh HISTORY
|
|
The
|
|
.Nm
|
|
manual page first appeared in
|
|
.Fx 3.0 .
|
|
.Sh AUTHORS
|
|
This
|
|
manual page was written by
|
|
.An Nicolas Souchu .
|