ch376-native: optimised calling convention for usb_init

Source/HBIOS/ch376-native/base-drv/ch376_init.c.s

@@ -55,22 +55,22 @@ _wait_for_state:
 	add	ix,sp
 	dec	sp
 	ld	(ix-1),a
-	ld	b, l
 ;source-doc/base-drv/ch376_init.c:5: uint16_t r = state;
-	ld	e, b
+	ld	c,l
+	ld	e,l
 ;source-doc/base-drv/ch376_init.c:7: for (uint8_t i = 0; i < loop_counter; i++) {
 	ld	d,0x00
-	ld	c,d
+	ld	b,d
 l_wait_for_state_00108:
-	ld	a, c
+	ld	a, b
 	sub	(ix-1)
 	jr	NC,l_wait_for_state_00106
 ;source-doc/base-drv/ch376_init.c:8: if (state == desired_state)
 	ld	a,(ix+4)
-	sub	b
+	sub	c
 	jr	Z,l_wait_for_state_00106
 ;source-doc/base-drv/ch376_init.c:11: if (i & 1)
-	bit	0, c
+	bit	0, b
 	jr	Z,l_wait_for_state_00104
 ;source-doc/base-drv/ch376_init.c:12: print_string("\b $");
 	push	bc
@@ -87,16 +87,14 @@ l_wait_for_state_00104:
 l_wait_for_state_00105:
 ;source-doc/base-drv/ch376_init.c:16: r     = usb_init(state);
 	push	bc
-	push	bc
-	inc	sp
+	ld	l, c
 	call	_usb_init
-	inc	sp
 	ex	de, hl
 	pop	bc
 ;source-doc/base-drv/ch376_init.c:17: state = r & 255;
-	ld	b, e
+	ld	c, e
 ;source-doc/base-drv/ch376_init.c:7: for (uint8_t i = 0; i < loop_counter; i++) {
-	inc	c
+	inc	b
 	jr	l_wait_for_state_00108
 l_wait_for_state_00106:
 ;source-doc/base-drv/ch376_init.c:20: return r;
@@ -142,16 +140,15 @@ l__chnative_init_00114:
 	ld	l,0x00
 	ld	a,(ix-1)
 	call	_wait_for_state
-	ld	b, e
 ;source-doc/base-drv/ch376_init.c:31: state = r & 255;
 ;source-doc/base-drv/ch376_init.c:33: print_string("\bPRESENT (VER $");
-	push	bc
+	push	de
 	ld	hl,ch376_init_str_3
 	call	_print_string
+	pop	de
 ;source-doc/base-drv/ch376_init.c:35: r     = usb_init(state);
-	inc	sp
+	ld	l, e
 	call	_usb_init
-	inc	sp
 	ex	de, hl
 ;source-doc/base-drv/ch376_init.c:36: state = r & 255;
 	ld	c, e
@@ -186,10 +183,9 @@ l__chnative_init_00102:
 	ld	l, c
 	ld	a,(ix-1)
 	call	_wait_for_state
-	ld	b, e
 ;source-doc/base-drv/ch376_init.c:49: state = r & 255;
 ;source-doc/base-drv/ch376_init.c:51: if (state == 2) {
-	ld	a, b
+	ld	a, e
 	sub	0x02
 	jr	NZ,l__chnative_init_00104
 ;source-doc/base-drv/ch376_init.c:52: print_string("\bDISCONNECTED$");
@@ -199,20 +195,20 @@ l__chnative_init_00102:
 	jr	l__chnative_init_00111
 l__chnative_init_00104:
 ;source-doc/base-drv/ch376_init.c:56: print_string("\bCONNECTED$");
-	push	bc
+	push	de
 	ld	hl,ch376_init_str_9
 	call	_print_string
+	pop	de
 ;source-doc/base-drv/ch376_init.c:59: r     = usb_init(state);
-	inc	sp
+	ld	l, e
 	call	_usb_init
-	inc	sp
 	ex	de, hl
 ;source-doc/base-drv/ch376_init.c:60: state = r & 255;
-	ld	b, e
+	ld	c, e
 ;source-doc/base-drv/ch376_init.c:62: for (uint8_t i = 0; i < loop_counter; i++) {
-	ld	c,0x00
+	ld	b,0x00
 l__chnative_init_00109:
-	ld	a, c
+	ld	a, b
 	sub	(ix-1)
 	jr	NC,l__chnative_init_00111
 ;source-doc/base-drv/ch376_init.c:63: if (r >> 8 != 0)
@@ -226,16 +222,14 @@ l__chnative_init_00109:
 	pop	bc
 ;source-doc/base-drv/ch376_init.c:67: r     = usb_init(state);
 	push	bc
-	push	bc
-	inc	sp
+	ld	l, c
 	call	_usb_init
-	inc	sp
 	ex	de, hl
 	pop	bc
 ;source-doc/base-drv/ch376_init.c:68: state = r & 255;
-	ld	b, e
+	ld	c, e
 ;source-doc/base-drv/ch376_init.c:62: for (uint8_t i = 0; i < loop_counter; i++) {
-	inc	c
+	inc	b
 	jr	l__chnative_init_00109
 l__chnative_init_00111:
 ;source-doc/base-drv/ch376_init.c:70: }

Source/HBIOS/ch376-native/base-drv/usb_init.c.s

@@ -83,20 +83,17 @@ _usb_host_bus_reset:
 	ld	l,0x00
 ;source-doc/base-drv/usb_init.c:20: }
 	ret
-;source-doc/base-drv/usb_init.c:24: uint16_t usb_init(uint8_t state) {
+;source-doc/base-drv/usb_init.c:24: uint16_t usb_init(uint8_t state) __z88dk_fastcall {
 ; ---------------------------------
 ; Function usb_init
 ; ---------------------------------
 _usb_init:
-	push	ix
-	ld	ix,0
-	add	ix,sp
 ;source-doc/base-drv/usb_init.c:27: USB_MODULE_LEDS = 0x03;
 	ld	a,0x03
 	ld	bc,_USB_MODULE_LEDS
 	out	(c), a
 ;source-doc/base-drv/usb_init.c:29: if (state == 0) {
-	ld	a,(ix+4)
+	ld	a, l
 	or	a
 	jr	NZ,l_usb_init_00104
 ;source-doc/base-drv/usb_init.c:30: ch_cmd_reset_all();
@@ -124,7 +121,7 @@ l_usb_init_00102:
 	jr	l_usb_init_00113
 l_usb_init_00104:
 ;source-doc/base-drv/usb_init.c:41: if (state == 1) {
-	ld	a,(ix+4)
+	ld	a, l
 	dec	a
 	jr	NZ,l_usb_init_00106
 ;source-doc/base-drv/usb_init.c:42: r = ch_cmd_get_ic_version();
@@ -140,7 +137,7 @@ l_usb_init_00104:
 	jr	l_usb_init_00113
 l_usb_init_00106:
 ;source-doc/base-drv/usb_init.c:48: if (state == 2) {
-	ld	a,(ix+4)
+	ld	a, l
 	sub	0x02
 	jr	NZ,l_usb_init_00159
 	ld	a,0x01
@@ -196,15 +193,11 @@ l_usb_init_00112:
 	ld	a,0x00
 	ld	bc,_USB_MODULE_LEDS
 	out	(c), a
-;source-doc/base-drv/usb_init.c:68: return (uint16_t)count_of_devices() << 8 | state + 1;
+;source-doc/base-drv/usb_init.c:68: return (uint16_t)count_of_devices() << 8 | 4;
 	call	_count_of_devices
-	ld	c,(ix+4)
-	ld	b,0x00
-	inc	bc
-	or	b
 	ld	h, a
-	ld	l, c
+	xor	a
+	ld	l,0x04
 l_usb_init_00113:
 ;source-doc/base-drv/usb_init.c:69: }
-	pop	ix
 	ret

Source/HBIOS/ch376-native/source-doc/base-drv/usb_init.c

@@ -21,7 +21,7 @@ static usb_error usb_host_bus_reset(void) {
 
 #define ERASE_LINE "\x1B\x6C\r$"
 
-uint16_t usb_init(uint8_t state) {
+uint16_t usb_init(uint8_t state) __z88dk_fastcall {
   uint8_t r;
 
   USB_MODULE_LEDS = 0x03;
@@ -65,5 +65,5 @@ uint16_t usb_init(uint8_t state) {
   }
   enumerate_all_devices();
   USB_MODULE_LEDS = 0x00;
-  return (uint16_t)count_of_devices() << 8 | state + 1;
+  return (uint16_t)count_of_devices() << 8 | 4;
 }

Source/HBIOS/ch376-native/source-doc/base-drv/usb_init.h

@@ -3,6 +3,6 @@
 
 #include <stdint.h>
 
-extern uint16_t usb_init(uint8_t state);
+extern uint16_t usb_init(uint8_t state) __z88dk_fastcall;
 
 #endif