1 files changed, 142 insertions, 0 deletions
diff --git a/src/target_dsp/calypso/bl_stage3.S b/src/target_dsp/calypso/bl_stage3.S
new file mode 100644
index 00000000..402c3c59
--- /dev/null
+++ b/src/target_dsp/calypso/bl_stage3.S
@@ -0,0 +1,142 @@
+
+BCSR		.equ	0x29
+
+CMD_IDLE	.equ	1		; Do nothing / DSP ready for commands
+CMD_COPY_BLOCK	.equ	2		; (if size == 0, then exec)
+CMD_COPY_MODE	.equ	4		; Select copy mode
+					; (0=code write, 1=data write,
+					;  2=code read,  3=data read,
+					;  4=prom read,  5=drom read)
+CMD_VERSION	.equ	0xffff		; API_RAM[0] = bootloader version
+
+VERSION		.equ	0x0100		; 1.00
+
+
+		.section .apiram
+
+		.org	0x07fc
+bl_addr_hi	.ds	1
+bl_size		.ds	1
+bl_addr_lo	.ds	1
+bl_status	.ds	1
+
+
+		.text
+		.mmregs
+_start:
+		orm     #2, *(BCSR)	; ?
+
+		ld	#0x1f, DP
+		stm	#0x1100, SP
+		stm	#0, AR4
+_done:
+		stm	#_api_ram, AR2
+		st	#CMD_IDLE, @bl_status
+_loop:
+		; Version
+		cmpm	@bl_status, #CMD_VERSION
+		bc	1f, ntc
+
+		bd	_done
+		st	#VERSION, *AR2
+1:
+
+		; Select copy mode
+		cmpm	@bl_status, #CMD_COPY_MODE
+		bc	1f, ntc
+
+		bd	_done
+		mvdm	@_api_ram, AR4
+1:
+
+		; Copy
+		cmpm	@bl_status, #CMD_COPY_BLOCK
+		bc	_loop, ntc
+
+		;   Capture values for copy operations
+		;     A = full address
+		;     AR1 size-1
+		;     AR2 api_ram (set previously)
+		;     AR3 data/code address
+		;     AR4 mode
+
+		ldu	@bl_addr_lo, A
+		stlm	A, AR3
+		add	@bl_addr_hi, 16, A
+
+		ldu	@bl_size, B
+		stlm	B, AR1
+		; mar	*AR1-	; We do this in a delay slot later on ...
+
+			; Start
+		bc	1f, bneq	; B still contains size
+		bacc	A
+
+1:
+			; Select
+		stm	#AR4, AR5	; AR5 = &AR4
+		bit	*AR5, 13	; Test mode(2)
+		bcd	_read_rom, tc
+		mar	*AR1-
+		bit	*AR5, 15	; Test mode(0) lsb
+		bcd	_copy_data, tc
+		bit	*AR5, 14	; Test mode(1)
+		nop
+
+			; Copy to/from Program space
+_copy_prog:
+		bc	_read_prog, tc
+
+				; Copy from API -> prog space	(mode 0)
+_write_prog:
+		rpt	*(AR1)
+		writa	*AR2+
+		b	_done
+
+				; Copy from prog space -> API	(mode 2)
+_read_prog:
+		rpt	*(AR1)
+		reada	*AR2+
+		b	_done
+
+			; Copy to/from Data space
+_copy_data:
+		bc	_read_data, tc
+
+				; Copy from API -> data space	(mode 1)
+_write_data:
+		rpt	*(AR1)
+		mvdd	*AR2+, *AR3+
+		b	_done
+
+				; Copy from data space -> API	(mode 3)
+_read_data:
+		rpt	*(AR1)
+		mvdd	*AR3+, *AR2+
+		b	_done
+
+			; Read from {D,P}ROM bypassing protection
+_read_rom:
+		ldm	AR1, B	; Can't put those two ops in the delay slot of
+		stlm	B, BRC	; 'bc' because of unprotected pipeline conflicts
+		bc	_read_rom_data, tc
+
+_read_rom_prog:
+		rptb	1f - 1
+		call	prom_read_xplt
+1:
+		b	_done
+
+_read_rom_data:
+		rptb	1f - 1
+		call	drom_read_xplt
+1:
+		b	_done
+
+
+drom_read_xplt	.equ	0xe4b8
+prom_read_xplt	.equ	0x7213
+
+
+		.end
+