1	********************************************************************
     2	* Boot - NitrOS-9 Lemma Boot Module
     3	*
     4	* $Id: boot_lemma.asm,v 1.2 2023/03/16 07:16:54 strick Exp strick $
     5	*
     6	* Edt/Rev  YYYY/MM/DD  Modified by
     7	* Comment
     8	* ------------------------------------------------------------------
     9	*   1      2023/03/15  Henry Strickland W6REK (github.com/strickyak)
    10	*
    11	* Created, based on boot_rom by Boisy G. Pitre for boilerplate,
    12	*          and Michael Furman N6IL's cocoio-dw repository
    13	*          (github.com/n6il).
    14	
    15	******
    16	*
    17	* Lemma Definitions
    18	Q.BfBegin equ 211  ; quint { cmd total_size.hi total_size.lo 0 0 }
    19	Q.BfChunk equ 212  ; quint { cmd chunk_size.hi chunk_size.lo 0 0 }
    20	Q.BfEnd   equ 213  ; quint { cmd total_size.hi total_size.lo 0 0 }
    21	
    22	;; Page 0 between $11 and $20 is unused in OS9 Level 1.
    23	;; TODO use stack instead.  Drivewire scribbles stats here.
    24	BeginPtr  equ $12
    25	CurrPtr   equ $14
    26	Quint     equ $16
    27	QuintN    equ $17
    28	QuintSize equ 5     ; quint is 5 bytes
    29	*
    30	******
    31	
    32	         nam   Boot
    33	         ttl   NitrOS-9 Level 1 Lemma Boot Module
    34	
    35	         ifp1
    36	         use   defsfile
    37	         use   cocoio.d
    38	         use   w5100s.d
    39	         endc
    40	
    41	tylg     set   Systm+Objct
    42	atrv     set   ReEnt+rev
    43	rev      set   $01
    44	edition  set   1
    45	
    46	         mod   eom,name,tylg,atrv,start,size
    47	
    48	size     equ   .
    49	
    50	name     fcs   /Boot/
    51	         fcb   edition
    52	
    53	
    54	;;  Load Quint (for Q.BfBegin)
    55	;;  Assert BfSize, and get sz.
    56	;;  
    57	;;  F$SRqMem D=sz => U=begin
    58	;;  current := begin
    59	;;  
    60	;;  LOOP:
    61	;;  	Load Quint.
    62	;;  	If BfEnd{ s } , return: X=begin D=sz
    63	;;  
    64	;;  	Assert BfChunk{ chunk_sz }
    65	;;  
    66	;;  	Read(current, chunk_sz }
    67	;;  	current += chunk_sz
    68	;;  
    69	;;  GOTO LOOP;
    70	
    71	start    pshs  u,y,dp
    72		clra
    73		tfr a,dp       ; we use DP=0.
    74	
    75	  jsr ReadQuint
    76		ldd <QuintN    ; D<-sz
    77	
    78	  os9 F$SRqMem
    79		stu <BeginPtr 
    80		stu <CurrPtr 
    81	
    82	Loop
    83	  jsr ReadQuint  ; read Q.BfChunk or Q.BfEnd quint.
    84		lda <Quint
    85		cmpa #Q.BfEnd
    86		beq Return
    87	  
    88		ldx <CurrPtr
    89		ldy <QuintN
    90		jsr Tcp1Read     ; read data packet
    91	
    92		ldd <CurrPtr
    93		addd <QuintN
    94		std <CurrPtr
    95	
    96	  bra Loop
    97	
    98	* We return to the kernel with
    99	*    X = address of bootfile
   100	*    D = size of bootfile
   101	Return
   102	  clra           ; resets carry.
   103	  ldx <BeginPtr
   104		ldd <QuintN
   105	  puls  u,y,dp,pc
   106	
   107	ReadQuint
   108		LDX #Quint
   109		LDY #$0005
   110		jsr Tcp1Read
   111	
   112	**************************************************
   113	*
   114	*  {{{ The following is copied from github.com/n6il/cocoio-dw/dwread.asm
   115	*  with the subroutine `DwRead` renamed to `Tcp1Read`
   116	*  and the socket number changed from Socket 3 to Socket 1.
   117	*
   118	*  I suspect the code is by Michael Furman N6IL
   119	*  rather than the name in the comment, which seems to refer to
   120	*  serial drivewire instead of CocoIO ethernet.
   121	
   122	S1_RX_BUF	equ	$4800
   123	S1_TX_BUF	equ	$6800
   124	SKBUFSIZE	equ	$800
   125	SKBUFMASK	equ	$7ff
   126	
   127	* Tcp1Read
   128	*    Receive a response from the DriveWire server.
   129	*    Times out if serial port goes idle for more than 1.4 (0.7) seconds.
   130	*    Serial data format:  1-8-N-1
   131	*    4/12/2009 by Darren Atkinson
   132	*
   133	* Entry:
   134	*    X  = starting address where data is to be stored
   135	*    Y  = number of bytes expected
   136	*
   137	* Exit:
   138	*    CC = carry set on framing error, Z set if all bytes received
   139	*    X  = starting address of data received
   140	*    Y  = checksum
   141	*    U is preserved.  All accumulators are clobbered
   142	
   143	Tcp1Read
   144		pshs u
   145	* space for variables on stack
   146		leas -10,s
   147		leau ,s
   148	
   149	* temp	 	rmb 2  ,u
   150	* rptr		rmb 2 2,u
   151	* roffset	rmb 2 4,u
   152	* rsize 	rmb 2 6,u
   153	* len	 	rmb 2 8,u
   154	
   155	* loop until sufficient bytes available
   156		sty ,u	* exptectd bytes => temp
   157		sty 8,u	* exptectd bytes => len
   158	@loop
   159		ldd #S3_RX_RSR0
   160		std CIO0ADDR
   161		lda CIO0DATA
   162		sta 6,u	* rsize msb
   163		ldb CIO0DATA
   164		stb 7,u * rsize lsb
   165		subd ,u * S3_RX_RSR0 - temp
   166		blo @loop
   167	* all bytes we want are available for reading now
   168	
   169	* get current pointer in receive buffer
   170		ldd #S3_RX_RD0
   171		std CIO0ADDR
   172		lda CIO0DATA
   173		sta 2,u	* rptr msb
   174		ldb CIO0DATA
   175		stb 3,u * rptr lsb
   176	
   177	* offset into receive buffer
   178	* roffset = rptr & SKBUFMASK
   179		andd #SKBUFMASK
   180		std 4,u * roffset
   181	
   182	* The receieve buffer is circular. Check if we need to read from it in two
   183	*    parts or one
   184	*  if(roffset + len > SKBUFMASK)
   185		sty ,u	* exptectd bytes => temp
   186		addd ,u	* roffset + temp	
   187		cmpd #SKBUFMASK
   188		ble once
   189	twice
   190	* 1) Read to end of buffer
   191		pshs y ; len
   192	* rsize = SKBUFSIZE - roffset
   193		ldd #SKBUFSIZE
   194		subd 4,u * roffset
   195		std 6,u * rsize
   196	* rgblkget(buf, sockp->skrbstrt + roffset, rsize)
   197		tfr d,y
   198		ldd 4,u * rofset
   199		addd #S1_RX_BUF
   200		std ,u  * temp
   201		jsr w51rd
   202	
   203	* 2) Read remainder from beginning of buffer
   204	* rgblkget(buf + rsize, sockp->skrbstrt, len - rsize)
   205		ldd #S1_RX_BUF
   206		std ,u * temp
   207		puls d * len
   208		subd 6,u * rsize
   209		tfr d,y	
   210		bra doonce
   211	once
   212	* rgblkget(buf, sockp->skrbstrt + roffset, len)
   213		ldd #S1_RX_BUF
   214		addd 4,u * roffset
   215		std ,u * temp
   216	doonce
   217		jsr w51rd
   218	advance
   219		ldd #S3_RX_RD0
   220		std CIO0ADDR
   221		ldd 8,u * len
   222		sta CIO0DATA
   223		stb CIO0DATA
   224	rxdone
   225		leas 10,s
   226		puls u,pc
   227	
   228	
   229	w51rd
   230	* x - buf
   231	* y - count
   232	* temp rgaddr
   233		ldd ,u * temp
   234		std CIO0ADDR
   235		bra @check
   236	@loop
   237		lda 	CIO0DATA
   238		sta	,x+
   239		leay -1,y
   240	@check
   241		cmpy #0
   242		bne @loop
   243		rts
   244	
   245	*  End copy from github.com/n6il/cocoio-dw/dwread.asm }}}
   246	*
   247	**************************************************
   248	
   249	         emod
   250	eom      equ   *