w5500: Rethink locking wrt interrupt handling

1 files changed, 85 insertions, 43 deletions

diff --git a/libhw/w5500.c b/libhw/w5500.c
index 7a5ba01..3d3e9ae 100644
--- a/libhw/w5500.c
+++ b/libhw/w5500.c
@@ -225,50 +225,55 @@ static COROUTINE w5500_irq_cr(void *_chip) {
 	cr_begin();
 
 	for (;;) {
-		while (!gpio_get(chip->pin_intr)) {
-			debugf("w5500_irq_cr(): gpio low");
-
-			uint8_t chipintr = w5500ll_read_common_reg(chip->spidev, chip_interrupt);
-			if (chipintr)
-				w5500ll_write_common_reg(chip->spidev, chip_interrupt, 0xFF);
-
-			uint8_t sockmask = w5500ll_read_common_reg(chip->spidev, sock_interrupt);
-			for (uint8_t socknum = 0; socknum < 8; socknum++) {
-				if (!(sockmask & (1<<socknum)))
-					continue;
-				struct _w5500_socket *socket = &chip->sockets[socknum];
-
-				uint8_t sockintr = w5500ll_read_sock_reg(chip->spidev, socknum, interrupt);
-				debugf("w5500_irq_cr(): sockintr=%"PRIu8, sockintr);
-
-				switch (socket->mode) {
-				case W5500_MODE_NONE:
-					break;
-				case W5500_MODE_TCP: case W5500_MODE_UDP:
-					uint8_t listen_bits = sockintr & SOCKINTR_CONN,
-						send_bits   = sockintr & (SOCKINTR_SEND_OK|SOCKINTR_SEND_TIMEOUT),
-						recv_bits   = sockintr & (SOCKINTR_RECV_DAT|SOCKINTR_RECV_FIN);
-
-					if (listen_bits) {
-						debugf("w5500_irq_cr(): signal sock[%"PRIu8"]->listen_sema", socknum);
-						cr_sema_signal(&socket->listen_sema);
-					}
-					if (recv_bits) {
-						debugf("w5500_irq_cr(): signal sock[%"PRIu8"]->read_sema", socknum);
-						cr_sema_signal(&socket->read_sema);
-					}
-					if (send_bits) {
-						debugf("w5500_irq_cr(): signal sock[%"PRIu8"]->write_ch", socknum);
-						_w5500_sockintr_ch_send(&socket->write_ch, send_bits);
-					}
-					break;
-				}
+		cr_mutex_lock(&chip->mu);
+		bool had_intr = false;
+
+		uint8_t chipintr = w5500ll_read_common_reg(chip->spidev, chip_interrupt);
+		debugf("w5500_irq_cr(): chipintr=%"PRIu8, chipintr);
+		had_intr = had_intr || (chipintr != 0);
+		if (chipintr)
+			w5500ll_write_common_reg(chip->spidev, chip_interrupt, 0xFF);
+
+		for (uint8_t socknum = 0; socknum < 8; socknum++) {
+			struct _w5500_socket *socket = &chip->sockets[socknum];
 
-				w5500ll_write_sock_reg(chip->spidev, socknum, interrupt, sockintr);
+			uint8_t sockintr = w5500ll_read_sock_reg(chip->spidev, socknum, interrupt);
+			debugf("w5500_irq_cr(): sockintr[%"PRIu8"]=%"PRIu8, socknum, sockintr);
+			had_intr = had_intr || (sockintr != 0);
+
+			switch (socket->mode) {
+			case W5500_MODE_NONE:
+				break;
+			case W5500_MODE_TCP: case W5500_MODE_UDP:
+				uint8_t listen_bits = sockintr & SOCKINTR_CONN,
+					send_bits   = sockintr & (SOCKINTR_SEND_OK|SOCKINTR_SEND_TIMEOUT),
+					recv_bits   = sockintr & (SOCKINTR_RECV_DAT|SOCKINTR_RECV_FIN);
+
+				if (listen_bits) {
+					debugf("w5500_irq_cr(): signal sock[%"PRIu8"]->listen_sema", socknum);
+					cr_sema_signal(&socket->listen_sema);
+				}
+				if (recv_bits) {
+					debugf("w5500_irq_cr(): signal sock[%"PRIu8"]->read_sema", socknum);
+					cr_sema_signal(&socket->read_sema);
+				}
+				if (send_bits) {
+					debugf("w5500_irq_cr(): signal sock[%"PRIu8"]->write_ch", socknum);
+					_w5500_sockintr_ch_send(&socket->write_ch, send_bits);
+				}
+				break;
 			}
+
+			w5500ll_write_sock_reg(chip->spidev, socknum, interrupt, sockintr);
 		}
-		cr_sema_wait(&chip->intr);
-		debugf("w5500_irq_cr(): sema signalled");
+
+		cr_mutex_unlock(&chip->mu);
+
+		if (!had_intr && gpio_get(chip->pin_intr)) {
+			debugf("w5500_irq_cr(): looks like all interrupts have been processed, sleeping...");
+			cr_sema_wait(&chip->intr);
+		} else
+			cr_yield();
 	}
 
 	cr_end();
@@ -291,11 +296,9 @@ static inline void w5500_socket_cmd(struct _w5500_socket *socket, uint8_t cmd) {
 	struct w5500 *chip = w5500_socket_chip(socket);
 	uint8_t socknum = socket->socknum;
 
-	cr_mutex_lock(&socket->cmd_mu);
 	w5500ll_write_sock_reg(chip->spidev, socknum, command, cmd);
 	while (w5500ll_read_sock_reg(chip->spidev, socknum, command) != 0x00)
 		cr_yield();
-	cr_mutex_unlock(&socket->cmd_mu);
 }
 
 static inline void w5500_socket_close(struct _w5500_socket *socket) {
@@ -425,20 +428,28 @@ static void w5500_post_reset(struct w5500 *chip) {
 }
 
 void w5500_hard_reset(struct w5500 *chip) {
+	cr_mutex_lock(&chip->mu);
+
 	gpio_put(chip->pin_reset, 0);
 	sleep_for_ms(1); /* minimum of 500us */
 	gpio_put(chip->pin_reset, 1);
 	sleep_for_ms(2); /* minimum of 1ms */
 
 	w5500_post_reset(chip);
+
+	cr_mutex_unlock(&chip->mu);
 }
 
 void w5500_soft_reset(struct w5500 *chip) {
+	cr_mutex_lock(&chip->mu);
+
 	w5500ll_write_common_reg(chip->spidev, mode, CHIPMODE_RST);
 	while (w5500ll_read_common_reg(chip->spidev, mode) & CHIPMODE_RST)
 		cr_yield();
 
 	w5500_post_reset(chip);
+
+	cr_mutex_unlock(&chip->mu);
 }
 
 static struct net_eth_addr w5500_if_hwaddr(implements_net_iface *_chip) {
@@ -452,9 +463,13 @@ static void _w5500_if_up(implements_net_iface *_chip, struct net_iface_config cf
 	struct w5500 *chip = VCALL_SELF(struct w5500, implements_net_iface, _chip);
 	assert(chip);
 
+	cr_mutex_lock(&chip->mu);
+
 	w5500ll_write_common_reg(chip->spidev, ip_gateway_addr, cfg.gateway_addr);
 	w5500ll_write_common_reg(chip->spidev, ip_subnet_mask, cfg.subnet_mask);
 	w5500ll_write_common_reg(chip->spidev, ip_addr, cfg.addr);
+
+	cr_mutex_unlock(&chip->mu);
 }
 
 static void w5500_if_up(implements_net_iface *_chip, struct net_iface_config cfg) {
@@ -518,6 +533,8 @@ static implements_net_stream_conn *w5500_if_tcp_dial(implements_net_iface *_chip
 	socket->read_open = socket->write_open = true;
 
  restart:
+	cr_mutex_lock(&chip->mu);
+
 	/* Mimics socket.c:socket().  */
 	w5500_socket_close(socket);
 	w5500ll_write_sock_reg(chip->spidev, socknum, mode, SOCKMODE_TCP);
@@ -530,6 +547,7 @@ static implements_net_stream_conn *w5500_if_tcp_dial(implements_net_iface *_chip
 	w5500ll_write_sock_reg(chip->spidev, socknum, remote_ip_addr, node);
 	w5500ll_write_sock_reg(chip->spidev, socknum, remote_port, uint16be_marshal(port));
 	w5500_socket_cmd(socket, CMD_CONNECT);
+	cr_mutex_unlock(&chip->mu);
 	for (;;) {
 		uint8_t state = w5500ll_read_sock_reg(chip->spidev, socknum, state);
 		debugf("tcp_dial(): state=%s", w5500_state_str(state));
@@ -566,12 +584,14 @@ static implements_net_packet_conn *w5500_if_udp_conn(implements_net_iface *_chip
 	socket->read_deadline_ns = 0;
 
 	/* Mimics socket.c:socket().  */
+	cr_mutex_lock(&chip->mu);
 	w5500_socket_close(socket);
 	w5500ll_write_sock_reg(chip->spidev, socknum, mode, SOCKMODE_UDP);
 	w5500ll_write_sock_reg(chip->spidev, socknum, local_port, uint16be_marshal(socket->port));
 	w5500_socket_cmd(socket, CMD_OPEN);
 	while (w5500ll_read_sock_reg(chip->spidev, socknum, state) != STATE_UDP)
 		cr_yield();
+	cr_mutex_unlock(&chip->mu);
 
 	return &socket->implements_net_packet_conn;
 }
@@ -587,6 +607,8 @@ static implements_net_stream_conn *w5500_tcplist_accept(implements_net_stream_li
 		return NULL;
 	}
 
+	cr_mutex_lock(&chip->mu);
+
 	/* Mimics socket.c:socket().  */
 	w5500_socket_close(socket);
 	w5500ll_write_sock_reg(chip->spidev, socknum, mode, SOCKMODE_TCP);
@@ -597,6 +619,7 @@ static implements_net_stream_conn *w5500_tcplist_accept(implements_net_stream_li
 
 	/* Mimics socket.c:listen().  */
 	w5500_socket_cmd(socket, CMD_LISTEN);
+	cr_mutex_unlock(&chip->mu);
 	for (;;) {
 		uint8_t state = w5500ll_read_sock_reg(chip->spidev, socknum, state);
 		debugf("tcp_listener.accept() => state=%s", w5500_state_str(state));
@@ -660,8 +683,10 @@ static ssize_t w5500_tcp_write(implements_net_stream_conn *_socket, void *buf, s
 			debugf(" => soft closed");
 			return -NET_ECLOSED;
 		}
+		cr_mutex_lock(&chip->mu);
 		uint8_t state = w5500ll_read_sock_reg(chip->spidev, socknum, state);
 		if (state != STATE_TCP_ESTABLISHED && state != STATE_TCP_CLOSE_WAIT) {
+			cr_mutex_unlock(&chip->mu);
 			debugf(" => hard closed");
 			return -NET_ECLOSED;
 		}
@@ -669,6 +694,7 @@ static ssize_t w5500_tcp_write(implements_net_stream_conn *_socket, void *buf, s
 		uint16_t freesize = uint16be_unmarshal(w5500ll_read_sock_reg(chip->spidev, socknum, tx_free_size));
 		if (freesize < count-done && freesize < min_free_space) {
 			/* Wait for more buffer space.  */
+			cr_mutex_unlock(&chip->mu);
 			cr_yield();
 			continue;
 		}
@@ -682,6 +708,8 @@ static ssize_t w5500_tcp_write(implements_net_stream_conn *_socket, void *buf, s
 
 		/* Submit the queue.  */
 		w5500_socket_cmd(socket, CMD_SEND);
+
+		cr_mutex_unlock(&chip->mu);
 		switch (_w5500_sockintr_ch_recv(&socket->write_ch)) {
 		case SOCKINTR_SEND_OK:
 			debugf(" => sent %zu", freesize);
@@ -737,6 +765,7 @@ static ssize_t w5500_tcp_read(implements_net_stream_conn *_socket, void *buf, si
 			debugf(" => recv timeout");
 			return -NET_ERECV_TIMEOUT;
 		}
+		cr_mutex_lock(&chip->mu);
 		uint8_t state = w5500ll_read_sock_reg(chip->spidev, socknum, state);
 		switch (state) {
 		case STATE_TCP_CLOSE_WAIT:
@@ -745,6 +774,7 @@ static ssize_t w5500_tcp_read(implements_net_stream_conn *_socket, void *buf, si
 			break; /* OK */
 		default:
 			VCALL(bootclock, del_trigger, &trigger);
+			cr_mutex_unlock(&chip->mu);
 			debugf(" => hard closed");
 			return -NET_ECLOSED;
 		}
@@ -755,10 +785,12 @@ static ssize_t w5500_tcp_read(implements_net_stream_conn *_socket, void *buf, si
 			break;
 		if (state == STATE_TCP_CLOSE_WAIT) {
 			VCALL(bootclock, del_trigger, &trigger);
+			cr_mutex_unlock(&chip->mu);
 			debugf(" => EOF");
 			return 0;
 		}
 
+		cr_mutex_unlock(&chip->mu);
 		cr_sema_wait(&socket->read_sema);
 	}
 	assert(avail);
@@ -773,6 +805,7 @@ static ssize_t w5500_tcp_read(implements_net_stream_conn *_socket, void *buf, si
 	w5500_socket_cmd(socket, CMD_RECV);
 	/* Return.  */
 	VCALL(bootclock, del_trigger, &trigger);
+	cr_mutex_unlock(&chip->mu);
 	return avail;
 }
 
@@ -784,6 +817,7 @@ static int w5500_tcp_close(implements_net_stream_conn *_socket, bool rd, bool wr
 		socket->read_open = false;
 
 	if (wr && socket->write_open) {
+		cr_mutex_lock(&chip->mu);
 		w5500_socket_cmd(socket, CMD_DISCON);
 		while (socket->write_open) {
 			uint8_t state = w5500ll_read_sock_reg(chip->spidev, socknum, state);
@@ -799,6 +833,7 @@ static int w5500_tcp_close(implements_net_stream_conn *_socket, bool rd, bool wr
 				break;
 			}
 		}
+		cr_mutex_unlock(&chip->mu);
 	}
 
 	w5500_tcp_maybe_free(chip, socket);
@@ -821,8 +856,10 @@ static ssize_t w5500_udp_sendto(implements_net_packet_conn *_socket, void *buf,
 	}
 
 	for (;;) {
+		cr_mutex_lock(&chip->mu);
 		uint8_t state = w5500ll_read_sock_reg(chip->spidev, socknum, state);
 		if (state != STATE_UDP) {
+			cr_mutex_unlock(&chip->mu);
 			debugf(" => closed");
 			return -NET_ECLOSED;
 		}
@@ -833,6 +870,7 @@ static ssize_t w5500_udp_sendto(implements_net_packet_conn *_socket, void *buf,
 			break;
 
 		/* Wait for more buffer space.  */
+		cr_mutex_unlock(&chip->mu);
 		cr_yield();
 	}
 
@@ -846,6 +884,7 @@ static ssize_t w5500_udp_sendto(implements_net_packet_conn *_socket, void *buf,
 	/* Submit the queue.  */
 	w5500_socket_cmd(socket, CMD_SEND);
 
+	cr_mutex_unlock(&chip->mu);
 	switch (_w5500_sockintr_ch_recv(&socket->write_ch)) {
 	case SOCKINTR_SEND_OK:
 		debugf(" => sent");
@@ -893,6 +932,7 @@ static ssize_t w5500_udp_recvfrom(implements_net_packet_conn *_socket, void *buf
 			debugf(" => recv timeout");
 			return -NET_ERECV_TIMEOUT;
 		}
+		cr_mutex_lock(&chip->mu);
 		uint8_t state = w5500ll_read_sock_reg(chip->spidev, socknum, state);
 		if (state != STATE_UDP) {
 			VCALL(bootclock, del_trigger, &trigger);
@@ -905,6 +945,7 @@ static ssize_t w5500_udp_recvfrom(implements_net_packet_conn *_socket, void *buf
 			/* We have data to read.  */
 			break;
 
+		cr_mutex_unlock(&chip->mu);
 		cr_sema_wait(&socket->read_sema);
 	}
 	assert(avail >= 8);
@@ -933,6 +974,7 @@ static ssize_t w5500_udp_recvfrom(implements_net_packet_conn *_socket, void *buf
 	w5500_socket_cmd(socket, CMD_RECV);
 	/* Return.  */
 	VCALL(bootclock, del_trigger, &trigger);
+	cr_mutex_unlock(&chip->mu);
 	return len;
 }