// Interface to the DS80C400 ROM functions. Largely based on code released
// by Dallas, hence the following copyright.

// ---------------------------------------------------------------------------
//  Copyright (C) 2003 Dallas Semiconductor Corporation, All Rights Reserved.
// 
//  Permission is hereby granted, free of charge, to any person obtaining a
//  copy of this software and associated documentation files (the "Software"),
//  to deal in the Software without restriction, including without limitation
//  the rights to use, copy, modify, merge, publish, distribute, sublicense,
//  and/or sell copies of the Software, and to permit persons to whom the
//  Software is furnished to do so, subject to the following conditions:
//
//  The above copyright notice and this permission notice shall be included
//  in all copies or substantial portions of the Software.
//
//  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
//  OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
//  MERCHANTABILITY,  FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
//  IN NO EVENT SHALL DALLAS SEMICONDUCTOR BE LIABLE FOR ANY CLAIM, DAMAGES
//  OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
//  ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
//  OTHER DEALINGS IN THE SOFTWARE.
//
//  Except as contained in this notice, the name of Dallas Semiconductor
//  shall not be used except as stated in the Dallas Semiconductor
//  Branding Policy.
// ---------------------------------------------------------------------------

#include <stdio.h>
#include <ds400rom.h>

// ROM globals, taken from startup400.a51
__data unsigned char __at (0x68) DSS_wos_crit_count;
__data unsigned int  __at (0x6b) DSS_timerReload;
__data unsigned char __at (0x6d) DSS_curr_pc[3];
__data unsigned char __at (0x72) DSS_sched[3];
__data unsigned char __at (0x74) DSS_ms_count[5];
__data unsigned char __at (0x7b) DSS_hb_chandle[5];
    
// Register bank 3 equates.
#define R0_B3     0x18
#define R1_B3     0x19
#define R2_B3     0x1A
#define R3_B3     0x1B
#define R4_B3     0x1C
#define R5_B3     0x1D
#define R6_B3     0x1E
#define R7_B3     0x1F


// The top of the redirect function table in RAM.
#define CALL_TABLE_TOP	256
    
// The bank the ROM is stored in.  Should be 0FFh for production
// 400's.  Change this value when running with a debug ROM.

#define ROM_BANK	0xFF

// The address of the ROM export table is stored
// at (ROM_BANK << 16) | ROM_EXPORTTABLE_OFFS

#define ROM_EXPORTTABLE_OFFS 	2

//
// Each entry in the ROM export table is 3 bytes.
//
#define ROMXT_ENTRYSIZE      3

//
// The number of functions in the ROM export table is stored
// first in the export table.
//
#define ROMXT_NUMFUNCTIONS     (0 * ROMXT_ENTRYSIZE)

//
// ROM EXPORT TABLE FUNCTIONS (denoted with ROMXT)
//

// UTILITY functions 
#define ROMXT_CRC16                     (1 * ROMXT_ENTRYSIZE) //
#define ROMXT_MEM_CLEAR_16              (2 * ROMXT_ENTRYSIZE) //
#define ROMXT_MEM_COPY_16               (3 * ROMXT_ENTRYSIZE) //
#define ROMXT_MEM_COMPARE               (4 * ROMXT_ENTRYSIZE) //
#define ROMXT_ADD_DPTR1_16              (5 * ROMXT_ENTRYSIZE) // not implemented for C compiler
#define ROMXT_ADD_DPTR2_16              (6 * ROMXT_ENTRYSIZE) // not implemented for C compiler
#define ROMXT_SUB_DPTR1_16              (7 * ROMXT_ENTRYSIZE) // not implemented for C compiler
#define ROMXT_SUB_DPTR2_16              (8 * ROMXT_ENTRYSIZE) // not implemented for C compiler
#define ROMXT_GETPSEUDORANDOM           (9 * ROMXT_ENTRYSIZE) //

// MEMORY MGR
#define ROMXT_KERNELMALLOC              (10 * ROMXT_ENTRYSIZE) // not exposed
#define ROMXT_KERNELFREE                (11 * ROMXT_ENTRYSIZE) // not exposed
#define ROMXT_MM_MALLOC                 (12 * ROMXT_ENTRYSIZE) // exposed as redirected function
#define ROMXT_MM_MALLOC_DIRTY           (13 * ROMXT_ENTRYSIZE) // exposed as redirected function
#define ROMXT_MM_FREE                   (14 * ROMXT_ENTRYSIZE) // exposed as redirected function
#define ROMXT_MM_DEREF                  (15 * ROMXT_ENTRYSIZE) // exposed as redirected function
#define ROMXT_GETFREERAM                (16 * ROMXT_ENTRYSIZE) // exposed as redirected function

// SOCKET functions
#define ROMXT_ROM_SOCKET                (17 * ROMXT_ENTRYSIZE) //
#define ROMXT_ROM_CLOSESOCKET           (18 * ROMXT_ENTRYSIZE) //
#define ROMXT_ROM_SENDTO                (19 * ROMXT_ENTRYSIZE) //
#define ROMXT_ROM_RECVFROM              (20 * ROMXT_ENTRYSIZE) //
#define ROMXT_ROM_CONNECT               (21 * ROMXT_ENTRYSIZE) //
#define ROMXT_ROM_BIND                  (22 * ROMXT_ENTRYSIZE) //
#define ROMXT_ROM_LISTEN                (23 * ROMXT_ENTRYSIZE) //
#define ROMXT_ROM_ACCEPT                (24 * ROMXT_ENTRYSIZE) //
#define ROMXT_ROM_RECV                  (25 * ROMXT_ENTRYSIZE) //
#define ROMXT_ROM_SEND                  (26 * ROMXT_ENTRYSIZE) //
#define ROMXT_ROM_GETSOCKOPT            (27 * ROMXT_ENTRYSIZE) //
#define ROMXT_ROM_SETSOCKOPT            (28 * ROMXT_ENTRYSIZE) //
#define ROMXT_ROM_GETSOCKNAME           (29 * ROMXT_ENTRYSIZE) //
#define ROMXT_ROM_GETPEERNAME           (30 * ROMXT_ENTRYSIZE) //
#define ROMXT_ROM_CLEANUP               (31 * ROMXT_ENTRYSIZE) //
#define ROMXT_ROM_AVAIL                 (32 * ROMXT_ENTRYSIZE) //
#define ROMXT_ROM_JOIN                  (33 * ROMXT_ENTRYSIZE) //
#define ROMXT_ROM_LEAVE                 (34 * ROMXT_ENTRYSIZE) //
#define ROMXT_ROM_PING                  (35 * ROMXT_ENTRYSIZE) //
#define ROMXT_ROM_GETNETWORKPARAMS      (36 * ROMXT_ENTRYSIZE) //
#define ROMXT_ROM_SETNETWORKPARAMS      (37 * ROMXT_ENTRYSIZE) //
#define ROMXT_ROM_GETIPV6PARAMS         (38 * ROMXT_ENTRYSIZE) //
#define ROMXT_ROM_GETETHERNETSTATUS     (39 * ROMXT_ENTRYSIZE) //
#define ROMXT_ROM_GETTFTPSERVER         (40 * ROMXT_ENTRYSIZE) //
#define ROMXT_ROM_SETTFTPSERVER         (41 * ROMXT_ENTRYSIZE) //
#define ROMXT_ETH_PROCESSINTERRUPT      (42 * ROMXT_ENTRYSIZE) // not implemented for C compiler
#define ROMXT_ARP_GENERATEREQUEST       (43 * ROMXT_ENTRYSIZE) // not implemented for C compiler
#define ROMXT_NET_ETH0_MAC_ID           (44 * ROMXT_ENTRYSIZE) //

// DHCP functions
#define ROMXT_DHCP_INIT                 (45 * ROMXT_ENTRYSIZE) //
#define ROMXT_DHCP_SETUP                (46 * ROMXT_ENTRYSIZE) // not implemented for C compiler
#define ROMXT_DHCP_STARTUP              (47 * ROMXT_ENTRYSIZE) // not implemented for C compiler
#define ROMXT_DHCP_RUN                  (48 * ROMXT_ENTRYSIZE) // not implemented for C compiler
#define ROMXT_DHCP_STATUS               (49 * ROMXT_ENTRYSIZE) //
#define ROMXT_DHCP_STOP                 (50 * ROMXT_ENTRYSIZE) //
#define ROMXT_DHCPNOTIFY                (51 * ROMXT_ENTRYSIZE) // empty redirect stub, not implemented

// TFTP functions
#define ROMXT_TFTP_INIT                 (52 * ROMXT_ENTRYSIZE) //
#define ROMXT_TFTP_FIRST                (53 * ROMXT_ENTRYSIZE) //
#define ROMXT_TFTP_NEXT                 (54 * ROMXT_ENTRYSIZE) //
#define ROMXT_TFTP_MSG                  (55 * ROMXT_ENTRYSIZE) //

// SCHEDULER functions
#define ROMXT_TASK_GENESIS              (56 * ROMXT_ENTRYSIZE) //
#define ROMXT_TASK_GETCURRENT           (57 * ROMXT_ENTRYSIZE) //
#define ROMXT_TASK_GETPRIORITY          (58 * ROMXT_ENTRYSIZE) //
#define ROMXT_TASK_SETPRIORITY          (59 * ROMXT_ENTRYSIZE) //
#define ROMXT_TASK_FORK                 (60 * ROMXT_ENTRYSIZE) //
#define ROMXT_TASK_KILL                 (61 * ROMXT_ENTRYSIZE) //
#define ROMXT_TASK_SUSPEND              (62 * ROMXT_ENTRYSIZE) //
#define ROMXT_TASK_SLEEP                (63 * ROMXT_ENTRYSIZE) //
#define ROMXT_TASK_SIGNAL               (64 * ROMXT_ENTRYSIZE) //
#define ROMXT_ROM_TASK_SWITCH_IN        (65 * ROMXT_ENTRYSIZE) // empty redirect stub, not implemented
#define ROMXT_ROM_TASK_SWITCH_OUT       (66 * ROMXT_ENTRYSIZE) // empty redirect stub, not implemented
#define ROMXT_ENTERCRITSECTION          (67 * ROMXT_ENTRYSIZE) //
#define ROMXT_LEAVECRITSECTION          (68 * ROMXT_ENTRYSIZE) //

// INIT functions
#define ROMXT_ROM_INIT                  (69 * ROMXT_ENTRYSIZE) //
#define ROMXT_ROM_COPYIVT               (70 * ROMXT_ENTRYSIZE) //
#define ROMXT_ROM_REDIRECT_INIT         (71 * ROMXT_ENTRYSIZE) //
#define ROMXT_MM_INIT                   (72 * ROMXT_ENTRYSIZE) //
#define ROMXT_KM_INIT                   (73 * ROMXT_ENTRYSIZE) //
#define ROMXT_OW_INIT                   (74 * ROMXT_ENTRYSIZE) //
#define ROMXT_NETWORK_INIT              (75 * ROMXT_ENTRYSIZE) //
#define ROMXT_ETH_INIT                  (76 * ROMXT_ENTRYSIZE) //
#define ROMXT_INIT_SOCKETS              (77 * ROMXT_ENTRYSIZE) //
#define ROMXT_TICK_INIT                 (78 * ROMXT_ENTRYSIZE) //

// Timer Interrupt vectors
#define ROMXT_WOS_TICK                  (79 * ROMXT_ENTRYSIZE) // not implemented for C compiler
#define ROMXT_BLOB                      (80 * ROMXT_ENTRYSIZE) // not implemented for C compiler

// Maintenance functions
#define ROMXT_WOS_IOPOLL                (81 * ROMXT_ENTRYSIZE) // not implemented for C compiler
#define ROMXT_IP_PROCESSRECEIVEQUEUES   (82 * ROMXT_ENTRYSIZE) // not implemented for C compiler
#define ROMXT_IP_PROCESSOUTPUT          (83 * ROMXT_ENTRYSIZE) // not implemented for C compiler
#define ROMXT_TCP_RETRYTOP              (84 * ROMXT_ENTRYSIZE) // not implemented for C compiler
#define ROMXT_ETH_PROCESSOUTPUT         (85 * ROMXT_ENTRYSIZE) // not implemented for C compiler
#define ROMXT_IGMP_GROUPMAINTAINENCE    (86 * ROMXT_ENTRYSIZE) // not implemented for C compiler
#define ROMXT_IP6_PROCESSRECEIVEQUEUES  (87 * ROMXT_ENTRYSIZE) // not implemented for C compiler
#define ROMXT_IP6_PROCESSOUTPUT         (88 * ROMXT_ENTRYSIZE) // not implemented for C compiler
#define ROMXT_PARAMBUFFER               (89 * ROMXT_ENTRYSIZE) // not implemented for C compiler
#define ROMXT_RAM_TOP                   (90 * ROMXT_ENTRYSIZE) // not implemented for C compiler
#define ROMXT_BOOT_MEMBEGIN             (91 * ROMXT_ENTRYSIZE) // not implemented for C compiler
#define ROMXT_BOOT_MEMEND               (92 * ROMXT_ENTRYSIZE) // not implemented for C compiler

// 1-Wire
#define ROMXT_OWM_FIRST                 (93 * ROMXT_ENTRYSIZE) //
#define ROMXT_OWM_NEXT                  (94 * ROMXT_ENTRYSIZE) //
#define ROMXT_OWM_RESET                 (95 * ROMXT_ENTRYSIZE) //
#define ROMXT_OWM_BYTE                  (96 * ROMXT_ENTRYSIZE) //
#define ROMXT_OWM_SEARCH                (97 * ROMXT_ENTRYSIZE) // not implemented for C compiler
#define ROMXT_OW_ROMID                  (98 * ROMXT_ENTRYSIZE) //

// Misc, extras, late additions
#define ROMXT_AUTOBAUD                  (99 * ROMXT_ENTRYSIZE)
#define ROMXT_TFTP_CLOSE                (100 * ROMXT_ENTRYSIZE)


#define ROMRT_ENTRYSIZE  3

//
// ROM REDIRECT TABLE FUNCTIONS (denoted with ROMRT)
//
#define ROMRT_KERNELMALLOC                  ( 1 * ROMRT_ENTRYSIZE)
#define ROMRT_KERNELFREE                    ( 2 * ROMRT_ENTRYSIZE)
#define ROMRT_MALLOC                        ( 3 * ROMRT_ENTRYSIZE)
#define ROMRT_FREE                          ( 4 * ROMRT_ENTRYSIZE)
#define ROMRT_MALLOCDIRTY                   ( 5 * ROMRT_ENTRYSIZE)
#define ROMRT_DEREF                         ( 6 * ROMRT_ENTRYSIZE)
#define ROMRT_GETFREERAM                    ( 7 * ROMRT_ENTRYSIZE)
#define ROMRT_GETTIMEMILLIS                 ( 8 * ROMRT_ENTRYSIZE)
#define ROMRT_GETTHREADID                   ( 9 * ROMRT_ENTRYSIZE)
#define ROMRT_THREADRESUME                  (10 * ROMRT_ENTRYSIZE)
#define ROMRT_THREADIOSLEEP                 (11 * ROMRT_ENTRYSIZE)
#define ROMRT_THREADIOSLEEPNC               (12 * ROMRT_ENTRYSIZE)
#define ROMRT_THREADSAVE                    (13 * ROMRT_ENTRYSIZE)
#define ROMRT_THREADRESTORE                 (14 * ROMRT_ENTRYSIZE)
#define ROMRT_SLEEP                         (15 * ROMRT_ENTRYSIZE)
#define ROMRT_GETTASKID                     (16 * ROMRT_ENTRYSIZE)
#define ROMRT_INFOSENDCHAR                  (17 * ROMRT_ENTRYSIZE)
#define ROMRT_IP_COMPUTECHECKSUM_SOFTWARE   (18 * ROMRT_ENTRYSIZE)
#define ROMRT_0                             (19 * ROMRT_ENTRYSIZE) // undefined
#define ROMRT_DHCPNOTIFY                    (20 * ROMRT_ENTRYSIZE)
#define ROMRT_ROM_TASK_CREATE               (21 * ROMRT_ENTRYSIZE)
#define ROMRT_ROM_TASK_DUPLICATE            (22 * ROMRT_ENTRYSIZE)
#define ROMRT_ROM_TASK_DESTROY              (23 * ROMRT_ENTRYSIZE)
#define ROMRT_ROM_TASK_SWITCH_IN            (24 * ROMRT_ENTRYSIZE)
#define ROMRT_ROM_TASK_SWITCH_OUT           (25 * ROMRT_ENTRYSIZE)
#define ROMRT_OWIP_READCONFIG               (26 * ROMRT_ENTRYSIZE)
#define ROMRT_SETMACID                      (27 * ROMRT_ENTRYSIZE)
#define ROMRT_UNDEREF                       (28 * ROMRT_ENTRYSIZE)


#define GETC		\
    clr  a		\
    movc a, @a+dptr
    

// expects function number in R6_B3 (low byte) & R7_B3 (high byte)
void _romcall(void) __naked
{
__asm    
      push  dpx                               ; dptr0 preserved here
      push  dph
      push  dpl

      ; point to the address of the table		
      mov   dptr, #(ROM_BANK << 16 | ROM_EXPORTTABLE_OFFS)

      push  acc                               ; acc preserved here
      push  b                                 ; b preserved here
      inc   dptr
      GETC                                    ; get the address of the table
      push  acc
      inc   dptr
      GETC
      add   a, R6_B3                          ; add function offset to the table
      mov   dpl, a
      pop   acc
      addc  a, R7_B3
      mov   dph, a

      ;
      ; dpx is the same, all in the same bank
      ;
      inc   dptr                              ; get the target address of the function we want
      GETC
      mov   b, a
      inc   dptr
      GETC
      mov   R3_B3, a
      mov   R4_B3, b
      mov   R5_B3, dpx                        ; high byte does not change
      pop   b                                 ; b restored here
      pop   acc                               ; acc restored here
      pop   dpl                               ; dptr0 preserved here
      pop   dph
      pop   dpx
      push  R3_B3                             ; push the target address
      push  R4_B3
      push  R5_B3
      ret                                     ; this is not a ret, it is a call!
	
      ; the called function ends with a ret which will return to our original caller.
__endasm ;
}

// expects function number in R6_B3 (low byte) & R7_B3 (high byte)
void _romredirect(void) __naked
{
__asm
      push  dpx
      push  dph
      push  dpl
      push  acc
      ; dptr = CALL_TABLE_TOP + function offset.
      mov   a, #(CALL_TABLE_TOP & 0xff)
      add   a, R6_B3                          ; add function offset to the table
      mov   dpl, a
      mov   a, #((CALL_TABLE_TOP >> 8) & 0xff)
      addc  a, R7_B3
      mov   dph, a
      mov   dpx, #((CALL_TABLE_TOP >> 16) & 0xff)
      movx  a, @dptr                      ; read high byte
      mov   R5_B3, a
      inc   dptr
      movx  a, @dptr                      ; read mid byte
      mov   R4_B3, a
      inc   dptr
      movx  a, @dptr                      ; read low byte
      mov   R3_B3, a
      pop   acc                 ; restore acc and dptr
      pop   dpl
      pop   dph
      pop   dpx
      push  R3_B3               ; push low byte of target address
      push  R4_B3
      push  R5_B3               ; push high byte of target address
      ret                       ; this is not a ret, it is a call!

      ; the called function ends with a ret which will return to our original caller.
__endasm;	
}


// This macro is invalid for the standard C preprocessor, since it
// includes a hash character in the expansion, hence the SDCC specific
// pragma.
#pragma sdcc_hash +
#define ROMCALL(x) \
	mov     R6_B3, #(x & 0xff) 		\
	mov     R7_B3, #((x >> 8) & 0xff)	\
	lcall   __romcall

#define ROMREDIRECT(x) \
	mov     R6_B3, #(x & 0xff) 		\
	mov     R7_B3, #((x >> 8) & 0xff)	\
	lcall   __romredirect


// init_rom: the ds400 ROM_INIT ROM function.
unsigned char init_rom(void __xdata *loMem,
		       void __xdata *hiMem) __naked
{    
    // shut compiler up about unused parameters.
    loMem;
    hiMem;
    
__asm
	; load params.
	; loMem is already in DPTR.
	mov	r2, dpx
	mov	r1, dph
	mov     r0, dpl
	; hiMem is in _init_rom_PARM_2
	mov	dptr, #_init_rom_PARM_2
	mov	r5, dpx
	mov     r4, dph
	mov     r3, dpl

	ROMCALL(ROMXT_ROM_INIT)

	; result is in acc, move to dpl for C convention.
	mov	dpl, a
	ret
__endasm	;
}

// DSS_gettimemillis: note that the ROM actually returns 5 bytes of time,
// we're discarding the high byte here.
unsigned long task_gettimemillis_long(void) __naked
{
__asm    
    ; no parameters to load. 
    ROMREDIRECT(ROMRT_GETTIMEMILLIS)
   ; results in r4 - r0, return in DPTR/B
   mov dpl, r0
   mov dph, r1
   mov dpx, r2
   mov b, r3
   ret
__endasm;
}

unsigned char task_getthreadID(void) __naked
{
__asm    
    ; no parameters to load. 
    ROMREDIRECT(ROMRT_GETTHREADID)
   ; results in acc, return in dpl
   mov dpl, a
   ret
__endasm;    
}

unsigned int task_gettickreload(void)
{
    return DSS_timerReload;
}

void task_settickreload(unsigned int rl)
{
    DSS_timerReload = rl;
}

