Merge branch 'lukeshu/linkdown'HEADmain

2 files changed, 94 insertions, 23 deletions

diff --git a/libhw_cr/rp2040_include/libhw/w5500.h b/libhw_cr/rp2040_include/libhw/w5500.h
index 43c58a3..d4ca4de 100644
--- a/libhw_cr/rp2040_include/libhw/w5500.h
+++ b/libhw_cr/rp2040_include/libhw/w5500.h
@@ -12,6 +12,7 @@
 #include <libcr_ipc/chan.h>
 #include <libcr_ipc/mutex.h>
 #include <libcr_ipc/sema.h>
+#include <libmisc/linkedlist.h>
 #include <libmisc/private.h>
 
 #include <libhw/generic/net.h>
@@ -41,19 +42,23 @@ struct _w5500_socket {
 	END_PRIVATE(LIBHW_W5500_H);
 };
 
+SLIST_DECLARE(_w5500_link_waitlist);
+
 struct w5500 {
 	BEGIN_PRIVATE(LIBHW_W5500_H);
 	/* const-after-init */
 	lo_interface spi                 spidev;
 	uint                             pin_intr;
 	uint                             pin_reset;
+	uint                             pin_linkled;
 	struct net_eth_addr              hwaddr;
 
 	/* mutable */
 	uint16_t                         next_local_port;
 	struct _w5500_socket             sockets[8];
 	struct _w5500_socket            *free;
-	cr_sema_t                        intr;
+	cr_sema_t                        intr_sema;
+	struct _w5500_link_waitlist      linkup_waiters;
 	cr_mutex_t                       mu;
 	END_PRIVATE(LIBHW_W5500_H);
 };
@@ -72,14 +77,21 @@ LO_IMPLEMENTATION_H(net_iface, struct w5500, w5500_if);
  *    the MCU know that it should do an SPI RPC "get" to see what
  *    happened.)
  *  - A reset pin that the MCU can pull low to reset the W5500.
+ *
+ * Additionally (even though it isn't supposed to be a line of
+ * communication with the MCU) we watch the link-LED output of the
+ * W5500 (low=has link, high=no link) to know when to do an SPI RPC
+ * "get" on the PHYCFG register for link status, since that isn't one
+ * of the things that triggers the interrupt pin.
  */
-#define w5500_init(self, name, spi, pin_intr, pin_reset, eth_addr) do { \
-		bi_decl(bi_2pins_with_names(pin_intr, name" interrupt", \
-		                            pin_reset, name" reset"));  \
-		_w5500_init(self, spi, pin_intr, pin_reset, eth_addr);  \
+#define w5500_init(self, name, spi, pin_intr, pin_reset, pin_linkled, eth_addr) do { \
+		bi_decl(bi_3pins_with_names(pin_intr, name" interrupt",              \
+		                            pin_reset, name" reset",                 \
+		                            pin_linkled, name" link-LED"));          \
+		_w5500_init(self, spi, pin_intr, pin_reset, pin_linkled, eth_addr);  \
 	} while (0)
 void _w5500_init(struct w5500 *self,
-                 lo_interface spi spi, uint pin_intr, uint pin_reset,
+                 lo_interface spi spi, uint pin_intr, uint pin_reset, uint pin_linkled,
                  struct net_eth_addr addr);
 
 /**
diff --git a/libhw_cr/w5500.c b/libhw_cr/w5500.c
index d757ca1..c519fc2 100644
--- a/libhw_cr/w5500.c
+++ b/libhw_cr/w5500.c
@@ -179,6 +179,8 @@ static void w5500_tcp_maybe_free(struct w5500 *chip, struct _w5500_socket *sock)
 		w5500_free_socket(chip, sock);
 }
 
+SLIST_DECLARE_NODE(_w5500_link_waitlist, cid_t);
+
 static COROUTINE w5500_irq_cr(void *_chip) {
 	struct w5500 *chip = _chip;
 	cr_begin();
@@ -187,11 +189,13 @@ static COROUTINE w5500_irq_cr(void *_chip) {
 		cr_mutex_lock(&chip->mu);
 		bool had_intr = false;
 
+		bool linkdown = (w5500ll_read_common_reg(chip->spidev, phy_cfg) & PHYCFG_STAT_LINK) == 0;
+
 		uint8_t chipintr = w5500ll_read_common_reg(chip->spidev, chip_interrupt);
 		log_n_debugln(W5500_LL, "w5500_irq_cr(): chipintr=", (base2_u8_, chipintr));
 		had_intr = had_intr || (chipintr != 0);
 		if (chipintr)
-			w5500ll_write_common_reg(chip->spidev, chip_interrupt, 0xFF);
+			w5500ll_write_common_reg(chip->spidev, chip_interrupt, chipintr);
 
 		for (uint8_t socknum = 0; socknum < 8; socknum++) {
 			struct _w5500_socket *socket = &chip->sockets[socknum];
@@ -212,11 +216,11 @@ static COROUTINE w5500_irq_cr(void *_chip) {
 					log_debugln("w5500_irq_cr(): signal sock[", socknum, "]->listen_sema");
 					cr_sema_signal(&socket->listen_sema);
 				}
-				if (recv_bits) {
+				if (recv_bits || linkdown) {
 					log_debugln("w5500_irq_cr(): signal sock[", socknum, "]->read_sema");
 					cr_sema_signal(&socket->read_sema);
 				}
-				if (send_bits) {
+				if (send_bits || (linkdown && cr_chan_can_send(&socket->write_ch))) {
 					log_debugln("w5500_irq_cr(): signal sock[", socknum, "]->write_ch");
 					cr_chan_send(&socket->write_ch, send_bits);
 				}
@@ -226,11 +230,16 @@ static COROUTINE w5500_irq_cr(void *_chip) {
 			w5500ll_write_sock_reg(chip->spidev, socknum, interrupt, sockintr);
 		}
 
+		if (chip->linkup_waiters.front && !linkdown) {
+			log_debugln("w5500_irq_cr(): signal linkup_waiters");
+			cr_unpause(slist_pop_from_front(&chip->linkup_waiters)->val);
+		}
+
 		cr_mutex_unlock(&chip->mu);
 
 		if (!had_intr && gpio_get(chip->pin_intr)) {
 			log_debugln("w5500_irq_cr(): looks like all interrupts have been processed, sleeping...");
-			cr_sema_wait(&chip->intr);
+			cr_sema_wait(&chip->intr_sema);
 		} else
 			cr_yield();
 	}
@@ -282,21 +291,22 @@ static inline void w5500_socket_close(struct _w5500_socket *socket) {
 
 /* init() *********************************************************************/
 
-static void w5500_intrhandler(void *_chip, uint LM_UNUSED(gpio), enum gpio_irq_level LM_UNUSED(event)) {
+static void w5500_intrhandler(void *_chip, uint gpio, enum gpio_irq_level LM_UNUSED(event)) {
 	struct w5500 *chip = _chip;
-	log_debugln("w5500_intrhandler()");
-	cr_sema_signal_from_intrhandler(&chip->intr);
+	log_debugln("w5500_intrhandler(gpio=", gpio, ")");
+	cr_sema_signal_from_intrhandler(&chip->intr_sema);
 }
 
 void _w5500_init(struct w5500 *chip,
-                 lo_interface spi spi, uint pin_intr, uint pin_reset,
+                 lo_interface spi spi, uint pin_intr, uint pin_reset, uint pin_linkled,
                  struct net_eth_addr addr) {
 	assert(chip);
 	assert(!LO_IS_NULL(spi));
 
 	/* Initialize the pads.  */
-	gpiopad_configure(pin_intr,  GPIOPAD_CONF(IN(SCHMITT), NOOUT,          PULL_DOWN));
-	gpiopad_configure(pin_reset, GPIOPAD_CONF(NOIN,        OUT(4MA, SLOW), PULL_DOWN));
+	gpiopad_configure(pin_intr,    GPIOPAD_CONF(IN(SCHMITT), NOOUT,          PULL_DOWN));
+	gpiopad_configure(pin_reset,   GPIOPAD_CONF(NOIN,        OUT(4MA, SLOW), PULL_DOWN));
+	gpiopad_configure(pin_linkled, GPIOPAD_CONF(IN(SCHMITT), NOOUT,          NO_PULL)); /* pulled up externally */
 
 	/* Initialize the data structures.  */
 	*chip = (struct w5500){
@@ -304,6 +314,7 @@ void _w5500_init(struct w5500 *chip,
 		.spidev          = spi,
 		.pin_intr        = pin_intr,
 		.pin_reset       = pin_reset,
+		.pin_linkled     = pin_linkled,
 		.hwaddr          = addr,
 		/* mutable */
 		.next_local_port = CONFIG_W5500_LOCAL_PORT_MIN,
@@ -337,6 +348,8 @@ void _w5500_init(struct w5500 *chip,
 
 	/* Initialize the hardware.  */
 	gpioirq_set_and_enable_exclusive_handler(pin_intr, GPIO_IRQ_EDGE_FALL, w5500_intrhandler, chip);
+	gpioirq_set_and_enable_exclusive_handler(pin_linkled, GPIO_IRQ_EDGE_FALL, w5500_intrhandler, chip);
+	gpioirq_set_and_enable_exclusive_handler(pin_linkled, GPIO_IRQ_EDGE_RISE, w5500_intrhandler, chip);
 	gpio_set_dir(chip->pin_reset, GPIO_OUT);
 	w5500_hard_reset(chip);
 
@@ -349,8 +362,9 @@ void _w5500_init(struct w5500 *chip,
 
 static void w5500_ifdown(struct w5500 *chip) {
 	w5500ll_write_common_reg(chip->spidev, phy_cfg, PHYCFG_CONF(normal, powerdown));
-	/* Wait for the PHYCFG_STAT_LINK bit to clear.  */
-	while ((w5500ll_read_common_reg(chip->spidev, phy_cfg) & (PHYCFG_CONF_MASK|PHYCFG_STAT_LINK)) != PHYCFG_CONF(normal, powerdown))
+	/* Wait for the PHYCFG_STAT_LINK bit to clear and the link-LED to turn off.  */
+	while ((w5500ll_read_common_reg(chip->spidev, phy_cfg) & (PHYCFG_CONF_MASK|PHYCFG_STAT_LINK)) != PHYCFG_CONF(normal, powerdown) ||
+	       !gpio_get(chip->pin_linkled))
 		cr_yield();
 }
 
@@ -505,6 +519,24 @@ void w5500_if_ifup(struct w5500 *chip) {
 	cr_mutex_unlock(&chip->mu);
 }
 
+bool w5500_if_is_link_up(struct w5500 *chip) {
+	cr_mutex_lock(&chip->mu);
+	bool linkup = (w5500ll_read_common_reg(chip->spidev, phy_cfg) & PHYCFG_STAT_LINK) != 0;
+	cr_mutex_unlock(&chip->mu);
+	return linkup;
+}
+
+void w5500_if_wait_for_link_up(struct w5500 *chip) {
+	struct _w5500_link_waitlist_node self = {
+		.val = cr_getcid(),
+	};
+	slist_push_to_rear(&chip->linkup_waiters, &self);
+	cr_sema_signal(&chip->intr_sema);
+	cr_pause_and_yield();
+	if (chip->linkup_waiters.front)
+		cr_unpause(slist_pop_from_front(&chip->linkup_waiters)->val);
+}
+
 lo_interface net_stream_listener w5500_if_tcp_listen(struct w5500 *chip, uint16_t local_port) {
 	assert(chip);
 
@@ -721,6 +753,11 @@ static size_t_and_error w5500_tcp_writev(struct _w5500_socket *socket, const str
 			return ERROR_AND(size_t, done, error_new(E_NET_ECLOSED));
 		}
 		cr_mutex_lock(&chip->mu);
+		if ((w5500ll_read_common_reg(chip->spidev, phy_cfg) & PHYCFG_STAT_LINK) == 0) {
+			cr_mutex_unlock(&chip->mu);
+			log_debugln(" => network down");
+			return ERROR_AND(size_t, done, error_new(E_POSIX_ENETDOWN));
+		}
 		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);
@@ -746,8 +783,11 @@ static size_t_and_error w5500_tcp_writev(struct _w5500_socket *socket, const str
 		/* Submit the queue.  */
 		w5500_socket_cmd(socket, CMD_SEND);
 
-		cr_mutex_unlock(&chip->mu);
+		cr_mutex_unlock(&chip->mu); /* NB: cr_mutex_unlock() never yields */
 		switch (cr_chan_recv(&socket->write_ch)) {
+		case 0:
+			log_debugln(" => network down");
+			return ERROR_AND(size_t, done, error_new(E_POSIX_ENETDOWN));
 		case SOCKINTR_SEND_OK:
 			log_debugln(" => sent ", freesize);
 			done += freesize;
@@ -807,6 +847,12 @@ static size_t_or_error w5500_tcp_readv(struct _w5500_socket *socket, const struc
 			return ERROR_NEW_ERR(size_t, error_new(E_NET_ERECV_TIMEOUT));
 		}
 		cr_mutex_lock(&chip->mu);
+		if ((w5500ll_read_common_reg(chip->spidev, phy_cfg) & PHYCFG_STAT_LINK) == 0) {
+			LO_CALL(bootclock, del_trigger, &trigger);
+			cr_mutex_unlock(&chip->mu);
+			log_debugln(" => network down");
+			return ERROR_NEW_ERR(size_t, error_new(E_POSIX_ENETDOWN));
+		}
 		uint8_t state = w5500ll_read_sock_reg(chip->spidev, socknum, state);
 		switch (state) {
 		case STATE_TCP_CLOSE_WAIT:
@@ -902,8 +948,12 @@ static error w5500_udp_sendto(struct _w5500_socket *socket, void *buf, size_t co
 
 	for (;;) {
 		cr_mutex_lock(&chip->mu);
-		uint8_t state = w5500ll_read_sock_reg(chip->spidev, socknum, state);
-		if (state != STATE_UDP) {
+		if ((w5500ll_read_common_reg(chip->spidev, phy_cfg) & PHYCFG_STAT_LINK) == 0) {
+			cr_mutex_unlock(&chip->mu);
+			log_debugln(" => network down");
+			return error_new(E_POSIX_ENETDOWN);
+		}
+		if (w5500ll_read_sock_reg(chip->spidev, socknum, state) != STATE_UDP) {
 			cr_mutex_unlock(&chip->mu);
 			log_debugln(" => closed");
 			return error_new(E_NET_ECLOSED);
@@ -934,6 +984,9 @@ static error w5500_udp_sendto(struct _w5500_socket *socket, void *buf, size_t co
 
 	cr_mutex_unlock(&chip->mu);
 	switch (cr_chan_recv(&socket->write_ch)) {
+	case 0:
+		log_debugln(" => network down");
+		return error_new(E_POSIX_ENETDOWN);
 	case SOCKINTR_SEND_OK:
 		log_debugln(" => sent");
 		return ERROR_NULL;
@@ -981,9 +1034,15 @@ static size_t_or_error w5500_udp_recvfrom(struct _w5500_socket *socket, void *bu
 			return ERROR_NEW_ERR(size_t, error_new(E_NET_ERECV_TIMEOUT));
 		}
 		cr_mutex_lock(&chip->mu);
-		uint8_t state = w5500ll_read_sock_reg(chip->spidev, socknum, state);
-		if (state != STATE_UDP) {
+		if ((w5500ll_read_common_reg(chip->spidev, phy_cfg) & PHYCFG_STAT_LINK) == 0) {
+			LO_CALL(bootclock, del_trigger, &trigger);
+			cr_mutex_unlock(&chip->mu);
+			log_debugln(" => network down");
+			return ERROR_NEW_ERR(size_t, error_new(E_POSIX_ENETDOWN));
+		}
+		if (w5500ll_read_sock_reg(chip->spidev, socknum, state) != STATE_UDP) {
 			LO_CALL(bootclock, del_trigger, &trigger);
+			cr_mutex_unlock(&chip->mu);
 			log_debugln(" => hard closed");
 			return ERROR_NEW_ERR(size_t, error_new(E_NET_ECLOSED));
 		}