startup.s

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        nop
        beq  r2,r3,Set25                 ; goto Set25
        addi r0,#0x7,r2                  ; r2 = 7 (SET23)
        nop
        beq  r2,r3,Set23                 ; goto Set23
        addi r0,#0x8,r2                  ; r2 = 7 (SET23)
        nop
        beq  r2,r3,Set4                 ; goto Set4
        addi r0,#0x9,r2                  ; r2 = 8 (SET4)
        nop
        beq  r2,r3,Set5                 ; goto Set5
        addi r0,#0xa,r2                  ; r2 = 9 (SET5)
        nop

NextCmd:
        addi r7,#0x1,r7                  ; increment loop counter
        addi r10,#0x10,r10               ; move pointer to next cmdblk
        bne  r7,r11,LoopCmd              ; loop if not done
        nop
        nop

Copy:
; copy data from source address to destination address
; arguments : src_addr, dest_addr, size
; Temp variables:
;       r13 : address of source data
;       r12 : address of destination
;       r6 : loop counter
;       r10: start address of command arguments
;
        ld   0x4[r10],r13                 ; address of source data
        ld   0x8[r10],r12                 ; address of destination
        ld   0xc[r10],r6                 ; r6 : loop countersize to copy
        nop
        beq   r0,r6,NextCmd              ; do copy if size > 0
        nop
        nop

LoopCopy:                                    
        ld   0x0[r13],r2                  ; load one dword
        nop
        nop                                  
        st   0x0[r12],r2                  ; copy to dest
        nop
        addi r13,#0x4,r13                  ; move pointer to next dword data
        addi r12,#0x4,r12                  ; move pointer to next target address
        addi r6,#-1,r6                   ; decrement loop counter
        bne  r6,r0,LoopCopy              ; loop copy
        nop
        nop
        beq   r0,r0,NextCmd              ; continue to next command if done
        nop
        nop
        
Clear:
; clear memory starting from given address to 0
; arguments : start_addr, size
; Temp variables:
;       r13 : address of source data
;       r6 : loop counter
;       r10: start address of command arguments
;
        ld   0x4[r10],r13                 ; starting address to clear
        ld   0x8[r10],r6                 ; loop counter : size to clear
        nop
        beq   r0,r6,NextCmd              ; do clear if size >0
        nop
        nop

LoopClear:
        st   0x0[r13],r0                  ; clear one dword
        nop
        addi r13,#0x4,r13                  ; move to next address
        addi r6,#-1,r6                   ; decrement loop counter
        bne  r6,r0,LoopClear             ; loop clear
        nop
        nop
        beq   r0,r0,NextCmd              ; continue to next command if done
        nop
        nop

Set25:
; set new value of r25
; arguments : value
; Temp variables:
;       r10: start address of command arguments
;
        beq  r0,r0,NextCmd               ; continue to next command
        ld   0x4[r10],r25                ; r25 = value
        nop


Set24:
; set new value of r24
; arguments : value
; Temp variables:
;       r10: start address of command arguments
;
        beq  r0,r0,NextCmd               ; continue to next command
        ld   0x4[r10],r24                ; r24 = value
        nop

Set23:
; set new value of r23
; arguments : value
; Temp variables:
;       r10: start address of command arguments
;
        beq  r0,r0,NextCmd               ; continue to next command
        ld   0x4[r10],r23                ; r23 = value
        nop

Set4:
; set new value of r4
; arguments : value
; Temp variables:
;       r10: start address of command arguments
;
        beq  r0,r0,NextCmd               ; continue to next command
        ld   0x4[r10],r4                ; r23 = value
        nop
 
Set5:
; set new value of r5
; arguments : value
; Temp variables:
;       r10: start address of command arguments
;
        beq  r0,r0,NextCmd               ; continue to next command
        ld   0x4[r10],r5                ; r23 = value
        nop
 

        
Jump:
; jump to given address
; arguments : dest_addr
; Temp variables:
;       r13 : address to jump to
;       r10: start address of command arguments
;
        ld   0x4[r10],r13                 ; r13 : address to jump
        nop
        jspci   r13,#0x0,r0               ; jump
	nop
	nop

Jsr:
; call subroutine starting at given address
; arguments : subroutine_addr
; Temp variables:
;       r13 : address to jump to
;       r10: start address of command arguments
;
        addi r0,#0xafe0,r29
        ld   0x4[r10],r13                 ; address to jump 
        nop
        st   0x20[r0],r6
        st   0x24[r0],r7
        jspci    r13,#0x0,r31
        st   0x28[r0],r10
        st   0x2c[r0],r11                ; save registers
        ld   0x20[r0],r6
        ld   0x24[r0],r7
        beq   r0,r0,NextCmd              ; continue to next command 
        ld   0x28[r0],r10
        ld   0x2c[r0],r11                ; restore registers

; Power up always starts here
; Temp. vars:
;	r1:	PSW
;	r2:	MEMWIDTH/mask
;	r3:	MEMDELAY
;	r12:	12000000h
;	r6;	10000000h
;	r21:	Read back from 10000000 (c3h is 3210!!)
;       r27:    omnibase
powerup:
        addi r0,#0xc3,r1
        movtos r1,psw			 ; set PSW
        addi r0,#0x2000,r27              ; r27 = 0x2000
        sh   r0,r27,r27,#16              ; r27 = r27 << 16 (i.e. omnibase)

	addi r0,#0x1200,r12
	sh   r0,r12,r12,#16		 ; r12 -> non-cachable DRAM 0
	addi r0,#0x1000,r6
	sh   r0,r6,r6,#16		 ; r6 -> non-cachable 0
					 ; (SRAM for 3208, DRAM for 3210)
	addi r0,#_WIDTH10_,r2	 	 ; Width for 3210 (bank 0 is DRAM)
	st   0x4000[r27],r2		 ; Set RIFACE_WIDTH

	; If the chip is 3210, then we can write to DRAM location and
	; read it back from the same location from bank 0. If the chip
	; is 3208, then bank 0 is not DRAM due to RIFACE_WIDTH set up
	st   0x1000[r12],r1		 ; Write 0xc3 to 0x12001000
	st   0x0000[r12],r0		 ; Change the data bus value in case
					 ; capacitor holds r1 value for the
					 ; next read
	ld   0x1000[r6],r21		 ; Read from 0x10000000
	addi r0,#0xff,r2		 ; r2 = 0xff (mask)
	and  r21,r2,r21			 ; Only look at the last 8b
	beq  r1,r21,set_delay
        addi r0,#_MEMDELAYH_,r3          ; r3  = 0x1d (3208 + wait state)
					 ; (Load delay)
        sh   r0,r3,r3,#16                ; r3  << = 16 (0x1d0000)

es3208:
	addi r0,#_MEMWIDTH_,r2		 ; r2 holds width setting for 3208
	st   0x4000[r27],r2		 ; Set RIFACE_WIDTH for 3208

set_delay:
        addi r3,#_MEMDELAYL_,r3          ; r3  = Wait states of memory banks
					 ; 1d001e = 1 (0x1a, 0, 0, 0x1e) or
					 ; 1d801e = 1 (0x1b, 0, 0, 0x1e)
					 ; which means: 3208
					 ; bank3:  5 (1a) or 4 (1b) wait states
					 ; bank2: 32 wait states
					 ; bank1: 32 wait states
					 ; bank0:  1 wait states
        st   0x4004[r27],r3              ; set RIFACE_WAIT_STATE
					 ; Bank3 : 3 wait state
        addi r0,#_DRAM_CONTROL_,r2	 ; r2  = DRAM configuration (0x204)
					 ; Browser board can also be set to
					 ; 0x2ea
        st   0x8100[r27],r2              ; set buscon_dram_control
;        nop
;        st   0x4008[r27],r0             ; RIFACE_TURNOFF_DELAY = 0
        st    0x0[r12],r21		 ; If it is 0xc3, then it is 3210;
					 ; Otherwise, it is 3208
        nop
        nop
        nop

        beq   r0,r0,ParseCmd             ; goto ParseCmd
	nop
        nop
LastLoc:
        nop