fixes for arm?

7 files changed, 83 insertions, 76 deletions

diff --git a/coroutine.c b/coroutine.c
index 6219883..34d84c8 100644
--- a/coroutine.c
+++ b/coroutine.c
@@ -52,15 +52,24 @@ static void call_with_stack(void *stack, cr_fn_t fn, void *args) {
 	                /* %1 */"r"(stack),
 	                /* %2 */"r"(fn),
 	                /* %3 */"r"(args)
-	              :
+	              : "rdi"
 	              );
 #elif __arm__
 #define STACK_GROWS_DOWNWARD 1
-	asm volatile ("mov r0, coroutine_table[_cur_cid].arg"
-	              "mov _saved_stack sp"
-	              "mov sp, coroutine_table[_cur_cid].stack"
-	              "bl  coroutine_table[_cur_cid].fn"
-	              "mov _saved_stack sp");
+	asm volatile ("mov r0, sp\n\t" /* [saved_sp = sp */
+	              "str r0, %0\n\t" /* ]  */
+	              "mov sp, %1\n\t" /* [sp = stack] */
+	              "mov r0, %1\n\t" /* [fn(arg0) */
+	              "blx %2\n\t"     /* ] */
+	              "ldr r0, %0\n\t" /* [sp = staved_sp */
+	              "mov sp, r0"     /* ] */
+	              :
+	              : /* %0 */"m"(saved_sp),
+	                /* %1 */"r"(stack),
+	                /* %2 */"r"(fn),
+	                /* %3 */"r"(args)
+	              : "r0"
+	              );
 #else
 #error unsupported architecture
 #endif
diff --git a/coroutine.h b/coroutine.h
index fbaf000..13f9797 100644
--- a/coroutine.h
+++ b/coroutine.h
@@ -54,7 +54,7 @@ cid_t cr_getcid(void);
 #define cr_chan_have_req(ch) ((ch)->requester != 0)
 #define cr_chan_recv_req(ch, _req_p) do {      \
 		(ch)->responder = cr_getcid(); \
-		if ((ch)->requester == 0) {    \
+		if ((ch)->requester == 0)      \
 			cr_pause_and_yield();  \
 		*(_req_p) = (ch)->req;         \
 	} while (0)
diff --git a/main.c b/main.c
index fef917f..098c3fd 100644
--- a/main.c
+++ b/main.c
@@ -4,66 +4,46 @@
  * SPDX-Licence-Identifier: AGPL-3.0-or-later
  */
 
+/* newlib */
+#include <string.h> /* for strlen() */
+
 /* pico-sdk */
-#include <stdio.h>
 #include "pico/stdlib.h"
 
-/* TinyUSB */
-#include "bsp/board_api.h"
-#include "tusb.h"
-
 /* local */
 #include "coroutine.h"
+#include "usb_common.h"
 #include "usb_keyboard.h"
 
-typedef struct {
-	usb_keyboard_chan_t *chan;
-	size_t               i;
-} hello_world_stack_t;
-
-void hello_world_cr(void *_stack) {
+COROUTINE hello_world_cr(void *_chan) {
 	const char *msg = "Hello world!\n";
-	hello_world_stack_t *stack = _stack;
-
+	usb_keyboard_chan_t *chan = _chan;
 	cr_begin();
-	for (;;) {
-		cr_chan_req(stack->chan, NULL, msg[stack->i]);
-		stack->i = (stack->i + 1) % strlen(msg);
+
+	for (size_t i = 0;; i = (i+1) % strlen(msg)) {
+		cr_chan_req(chan, NULL, msg[i]);
 	}
+
 	cr_end();
 }
 
 int main() {
-	/* pico-sdk initialization */
+	/* initialization */
 	stdio_uart_init();
-	gpio_init(PICO_DEFAULT_LED_PIN);
-	gpio_set_dir(PICO_DEFAULT_LED_PIN, GPIO_OUT);
+	//gpio_init(PICO_DEFAULT_LED_PIN);
+	//gpio_set_dir(PICO_DEFAULT_LED_PIN, GPIO_OUT);
 
+	usb_common_earlyinit();
 	usb_keyboard_init();
-
-	/* TinyUSB initialization */
-	board_init();
-	tud_init(BOARD_TUD_RHPORT);
-	if (board_init_after_tusb)
-		board_init_after_tusb();
-
-	/* coroutine initialization */
+	usb_common_lateinit();
 	coroutine_init();
 
+	/* set up coroutines */
+	coroutine_add(usb_common_cr, NULL);
 	usb_keyboard_chan_t keyboard_chan;
-
-	usb_keyboard_init();
-	usb_keyboard_stack_t usb_keyboard_stack = {0};
-	usb_keyboard_stack.chan = &keyboard_chan;
-	coroutine_add(usb_keyboard_cr, &usb_keyboard_stack);
-
-	hello_world_stack_t hello_world_stack = {0};
-	hello_world_stack.chan = &keyboard_chan;
-	coroutine_add(hello_world_cr, &hello_world_stack);
+	coroutine_add(usb_keyboard_cr, &keyboard_chan);
+	coroutine_add(hello_world_cr, &keyboard_chan);
 
 	/* Event loop. */
-	for (;;) {
-		tud_task();
-		coroutine_task();
-	}
+	coroutine_main();
 }
diff --git a/usb_common.c b/usb_common.c
index 65882b2..f10ace8 100644
--- a/usb_common.c
+++ b/usb_common.c
@@ -8,7 +8,7 @@
 #include <string.h>        /* memcpy(newlib) */
 #include <assert.h>        /* for assert(newlib) */
 #include <stdlib.h>        /* for malloc(pico_malloc), realloc(pico_malloc), reallocarray(pico_malloc) */
-#include "bsp/board_api.h" /* for board_usb_get_serial(TinyUSB) */
+#include "bsp/board_api.h" /* for board_init(), board_init_after_usb(), board_usb_get_serial(TinyUSB) */
 #include "tusb.h"          /* for various tusb_*_t types */
 
 #include "tusb_helpers.h" /* for LANGID_*, TU_UTF16() */
@@ -71,7 +71,7 @@ uint16_t const *tud_descriptor_string_cb(uint8_t strid, uint16_t langid) {
 
 uint8_t cfgnum_std = 0;
 
-void usb_common_init(void) {
+void usb_common_earlyinit(void) {
 	if (cfgnum_std)
 		return;
 	cfgnum_std = usb_add_config(
@@ -80,6 +80,25 @@ void usb_common_init(void) {
 		100);                               /* bMaxPower (in mA)   ; Maximum power consumption of the device when in this configuration */
 }
 		
+void usb_common_lateinit(void) {
+	board_init();
+	tud_init(BOARD_TUD_RHPORT);
+	if (board_init_after_tusb)
+		board_init_after_tusb();
+}
+
+COROUTINE usb_common_cr(void *_arg) {
+	(void) _arg;
+	cr_begin();
+
+	for (;;) {
+		tud_task();
+		cr_yield();
+	}
+
+	cr_end();
+}
+
 /* Main utilities *************************************************************/
 
 static uint8_t configc = 0;
diff --git a/usb_common.h b/usb_common.h
index a6006fa..3b45246 100644
--- a/usb_common.h
+++ b/usb_common.h
@@ -7,6 +7,8 @@
 #ifndef _USB_COMMON_H_
 #define _USB_COMMON_H_
 
+#include "coroutine.h"
+
 /* Strings ********************************************************************/
 
 enum {
@@ -25,7 +27,9 @@ enum {
 /* Globals ********************************************************************/
 
 extern uint8_t cfgnum_std;
-void usb_common_init(void);
+void usb_common_earlyinit(void);
+void usb_common_lateinit(void);
+COROUTINE usb_common_cr(void *arg);
 
 /* Main utilities *************************************************************/
 
diff --git a/usb_keyboard.c b/usb_keyboard.c
index 8212c60..e6638ec 100644
--- a/usb_keyboard.c
+++ b/usb_keyboard.c
@@ -21,7 +21,7 @@ static uint8_t kbd_ifc = 0;
 void usb_keyboard_init() {
 	if (kbd_ifc)
 		return;
-	usb_common_init();
+	usb_common_earlyinit();
 
 	kbd_ifc = usb_add_interface(cfgnum_std, TUD_HID_DESC_LEN, (uint8_t[]){
 		/* USB-HID input-only descriptor for inclusion in the config descriptor; consisting of 3 parts:
@@ -42,38 +42,41 @@ void usb_keyboard_init() {
 
 static uint8_t ascii2keycode[128][2] = { HID_ASCII_TO_KEYCODE };
 
-void usb_keyboard_cr(void *_stack) {
-	usb_keyboard_stack_t *stack = _stack;
-
+COROUTINE usb_keyboard_cr(void *_chan) {
+	usb_keyboard_chan_t *chan = _chan;
 	cr_begin();
 
+	uint8_t report_id   = 0;
+	uint8_t modifier    = 0;
+	uint8_t keycodes[6] = {0};
 	for (;;) {
 		while (!tud_hid_n_ready(kbd_ifc))
 			cr_yield();
 
-		if (cr_chan_have_req(stack->chan)) {
-			cr_chan_recv_req(stack->chan, &stack->rune);
+		if (cr_chan_have_req(chan)) {
+			uint32_t rune;
+			cr_chan_recv_req(chan, &rune);
 
-			stack->modifier = ascii2keycode[stack->rune][0] ? KEYBOARD_MODIFIER_LEFTSHIFT : 0;
-			stack->keycodes[0] = ascii2keycode[stack->rune][1];
-			tud_hid_n_keyboard_report(kbd_ifc, stack->report_id, stack->modifier, stack->keycodes);
+			modifier = ascii2keycode[rune][0] ? KEYBOARD_MODIFIER_LEFTSHIFT : 0;
+			keycodes[0] = ascii2keycode[rune][1];
+			tud_hid_n_keyboard_report(kbd_ifc, report_id, modifier, keycodes);
 
 			while (!tud_hid_n_ready(kbd_ifc))
 				cr_yield();
 
-			stack->modifier = 0;
-			stack->keycodes[0] = 0;
-			tud_hid_n_keyboard_report(kbd_ifc, stack->report_id, stack->modifier, stack->keycodes);
+			modifier = 0;
+			keycodes[0] = 0;
+			tud_hid_n_keyboard_report(kbd_ifc, report_id, modifier, keycodes);
 
-			cr_chan_send_resp(stack->chan, 1);
+			cr_chan_send_resp(chan, 1);
 		} else {
-			stack->modifier = 0;
-			stack->keycodes[0] = 0;
-			tud_hid_n_keyboard_report(kbd_ifc, stack->report_id, stack->modifier, stack->keycodes);
+			modifier = 0;
+			keycodes[0] = 0;
+			tud_hid_n_keyboard_report(kbd_ifc, report_id, modifier, keycodes);
 		}
 	}
 
-	cr_end()
+	cr_end();
 }
 
 /**
diff --git a/usb_keyboard.h b/usb_keyboard.h
index e989700..40b0bb2 100644
--- a/usb_keyboard.h
+++ b/usb_keyboard.h
@@ -11,15 +11,7 @@
 
 typedef cr_chan_t(uint32_t, int) usb_keyboard_chan_t;
 
-typedef struct {
-	usb_keyboard_chan_t *chan;
-	uint32_t             rune;
-	uint8_t              report_id;
-	uint8_t              modifier;
-	uint8_t              keycodes[0];
-} usb_keyboard_stack_t;
-
 void usb_keyboard_init(void);
-void usb_keyboard_cr(void *stack);
+COROUTINE usb_keyboard_cr(void *arg);
 
 #endif /* _USB_KEYBOARD_H_ */