wip

1 files changed, 91 insertions, 73 deletions

diff --git a/cmd/sbc_harness/hw/w5500.c b/cmd/sbc_harness/hw/w5500.c
index b4000f4..7470401 100644
--- a/cmd/sbc_harness/hw/w5500.c
+++ b/cmd/sbc_harness/hw/w5500.c
@@ -163,11 +163,11 @@ struct w5500_block_sock_reg {
 	uint8_t mode;                /* Sn_MR; see MODE_{x} below */
 	uint8_t command;             /* Sn_CR; see CMD_{x} below */
 	uint8_t interrupt;           /* Sn_IR */
-	uint8_t status;              /* Sn_SR; see STATUS_{x} below */
-	uint8_t local_port[2];         /* Sn_PORT0, Sn_PORT1 */
-	uint8_t remote_eth_addr[6];     /* Sn_DHAR0 ... SnDHAR5 */
-	uint8_t remote_ip_addr[4];      /* Sn_DIPR0 ... Sn_DIP3 */
-	uint8_t remote_port[2];         /* Sn_DPORT0 ... Sn_DPORT1 */
+	uint8_t state;               /* Sn_SR; see STATE_{x} below */
+	uint8_t local_port[2];       /* Sn_PORT0, Sn_PORT1 */
+	uint8_t remote_eth_addr[6];  /* Sn_DHAR0 ... SnDHAR5 */
+	uint8_t remote_ip_addr[4];   /* Sn_DIPR0 ... Sn_DIP3 */
+	uint8_t remote_port[2];      /* Sn_DPORT0 ... Sn_DPORT1 */
 
 	uint8_t max_seg_size[2];     /* Sn_MSSR0, Sn_MSSR1 */
 	uint8_t _reserved0[1];
@@ -218,74 +218,92 @@ static_assert(sizeof(struct w5500_block_sock_reg) == 0x30);
 #define CMD_SEND_KEEP ((uint8_t)0x22) /* TCP-only: send a keepalive without any data */
 #define CMD_RECV      ((uint8_t)0x40)
 
-#define STATUS_CLOSED          ((uint8_t)0x00)
+#define STATE_CLOSED          ((uint8_t)0x00)
 
-/* The status modes starting with an underscore are expected to be
- * very short-lived.  */
-
-#define STATUS_TCP_INIT        ((uint8_t)0x13)
-#define STATUS_TCP_LISTEN      ((uint8_t)0x14)
-#define _STATUS_TCP_SYNSENT    ((uint8_t)0x15) /* in the CMD_CONNECT INIT->SYNSENT->ESTABLISHED transition */
-#define _STATUS_TCP_SYNRECV    ((uint8_t)0x16) /* in the CMD_LISTEN LISTEN->SYNRECV->ESTABLISHED transition */
-#define STATUS_TCP_ESTABLISHED ((uint8_t)0x17)
-/* The "graceful shutdown" state diagram (with the exception that
- * reading the W5500's "status" register does not distinguish between
- * FIN_WAIT_1 and FIN_WAIT_2; it just has a single FIN_WAIT):
- *
- *                                                ║
- *                                                V
- *                                         ┌─────────────┐
- *                          "active close" │ ESTABLISHED │  "passive close"
- *                     (we send FIN first) └─────────────┘  (we send FIN second)
- *                                             V     V
- *                                 ╔═══════════╝     ╚═════════╗
- *                            (CMD_DISCON)                     ║
- *                        ┌┈┈┈<(send FIN)>┈┈┈┈┈┈┈┈┐            ║
- *                        ┊        ║              └┈┈┈┈┈┈┈>(recv FIN)
- *                        ┊        V              ┌┈┈┈┈┈┈┈<(send ACK)
- *    "double active"     ┊  ┌────────────┐       ┊            ║
- *   (both sides think    ┊  │ FIN_WAIT_1 │       ┊            V
- *  they sent FIN first)  ┊  └────────────┘       ┊     ┌────────────┐
- *                        ┊     V     V           ┊     │ CLOSE_WAIT │
- *            ╔═════════════════╝  ╔══╝           ┊     └────────────┘
- *        (recv FIN)<┈┈┈┈┈┤        ║              ┊            V
- *    ┌┈┈<(send ACK)>┈┈┈┐ ┊        ║              ┊            ║
- *    ┊       ║         └┈┈┈┈┈>(recv ACK)<┈┈┈┈┈┈┈┈┘            ║
- *    ┊       ║           ┊        ║                           ║
- *    ┊       V           ┊        V                           ║
- *    ┊  ┌─────────┐      ┊  ┌────────────┐                    ║
- *    ┊  │ CLOSING │      ┊  │ FIN_WAIT_2 │                    ║
- *    ┊  └─────────┘      ┊  └────────────┘                    ║
- *    ┊       V           ┊        V                      (CMD_DISCON)
- *    ┊       ║           ┊        ║              ┌┈┈┈┈┈┈┈<(send FIN)
- *    ┊       ║           └┈┈┈>(recv FIN)<┈┈┈┈┈┈┈┈┘            ║
- *    ┊       ║         ┌┈┈┈┈┈<(send ACK)>┈┈┈┈┈┈┈┈┐            V
- *    └┈┈>(recv ACK)<┈┈┈┘          ║              ┊       ┌──────────┐
- *            ╚═════════════════╗  ╚═╗            ┊       │ LAST_ACK │
- *                              V    V            ┊       └──────────┘
- *                           ┌───────────┐        ┊            V
- *                           │ TIME_WAIT │        ┊            ║
- *                           └───────────┘        └┈┈┈┈┈┈┈>(recv ACK)
- *                                 V                           ║
- *                                 ║                           ║
- *                         (2*MSL has elapsed)                 ║
- *                                 ╚═══════════╗    ╔══════════╝
- *                                             V    V
- *                                           ┌────────┐
- *                                           │ CLOSED │
- *                                           └────────┘
+/**
+ * The TCP state diagram is as follows.
+ *  - Reading the W5500's "state" register does not distinguish between FIN_WAIT_1 and FIN_WAIT_2;
+ *    it just has a single FIN_WAIT.
+ *  - At any point the state can jump to "CLOSED" either by CMD_CLOSE or by a timeout.
+ *  - Writing data is valid in ESTABLISHED and CLOSE_WAIT.
+ *  - Reading data is valid in ESTABLISHED and FIN_WAIT.
  *
- * One can still write in CLOSE_WAIT, and can still read in FIN_WAIT.
+ *                                              │ CLOSED │
+ *                                              └────────┘
+ *                                                   V
+ *                                               (CMD_OPEN)
+ *                                                   V
+ *                                              ┌────────┐
+ *     ┏━━━━━━━━━━━━━━━━┳━━━━━━━━━━━━━━━━━━━━━━━│  INIT  │━━━━━━━━━━━━━━━━━━━━━━━━┳━━━━━━━━━━━━━━━━┓
+ *     ┃ server         ┃                       └────────┘                        ┃         client ┃
+ *     ┣━━━━━━━━━━━━━━━━┛                         V ┃┃ V                          ┗━━━━━━━━━━━━━━━━┫
+ *     ┃                              ╔═══════════╝ ┃┃ ╚═══════════╗                               ┃
+ *     ┃                        (CMD_LISTEN)        ┃┃       (CMD_CONNECT)                         ┃
+ *     ┃                              V            ┌┃┃┈┈┈┈┈┈┈┈<(send SYN)                          ┃
+ *     ┃                         ┌────────┐        ┊┃┃             V                               ┃
+ *     ┃                         │ LISTEN │        ┊┃┃        ┌─────────┐                          ┃
+ *     ┃                         └────────┘        ┊┃┃        │ SYNSENT │                          ┃
+ *     ┃                              V            ┊┃┃        └─────────┘                          ┃
+ *     ┃                          (recv SYN)<┈┈┈┈┈┈┘┃┃             V                               ┃
+ *     ┃                        (send SYN+ACK)>┈┈┈┈┐┃┃             ║                               ┃
+ *     ┃                              V            └┃┃┈┈┈┈┈┈>(recv SYN+ACK)                        ┃
+ *     ┃                        ┌─────────┐        ┌┃┃┈┈┈┈┈┈┈┈<(send ack)                          ┃
+ *     ┃                        │ SYNRECV │        ┊┃┃             ║                               ┃
+ *     ┃                        └─────────┘        ┊┃┃             ║                               ┃
+ *     ┃                          V     V          ┊┃┃             ║                               ┃
+ *     ┃                          ║  (recv ACK)<┈┈┈┘┃┃             ║                               ┃
+ *     ┃                          ║     ╚═════════╗ ┃┃ ╔═══════════╝                               ┃
+ *     ┃                          ╚═══╗           V ┃┃ V                                           ┃
+ *     ┃                              ║       ┌─────────────┐                                      ┃
+ *     ┗━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━║━━━━━━━│ ESTABLISHED │━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━┛
+ *     ┏━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━║━━━━━━━└─────────────┘━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━┓
+ *     ┃                              ║           V ┃┃ V                                           ┃
+ *     ┃                              ╠═══════════╝ ┃┃ ╚═══════════╗                               ┃
+ *     ┃                         (CMD_DISCON)       ┃┃             ║                               ┃
+ *     ┃                     ┌┈┈┈<(send FIN)>┈┈┈┈┈┈┐┃┃             ║                               ┃
+ *     ┃                     ┊        V            └┃┃┈┈┈┈┈┈┈┈>(recv FIN)                          ┃
+ *     ┃                     ┊  ┌────────────┐     ┌┃┃┈┈┈┈┈┈┈┈<(send ACK)                          ┃
+ *     ┃                     ┊  │ FIN_WAIT_1 │     ┊┃┃             V                               ┃
+ *     ┃                     ┊  └────────────┘     ┊┃┃      ┌────────────┐                         ┃
+ *     ┃                     ┊     V     V         ┊┃┃      │ CLOSE_WAIT │                         ┃
+ *     ┃          ╔════════════════╝  ╔══╝         ┊┃┃      └────────────┘                         ┃
+ *     ┃      (recv FIN)<┈┈┈┈┤        ║            ┊┃┃             V                               ┃
+ *     ┃  ┌┈┈<(send ACK)>┈┈┐ ┊        ║            ┊┃┃             ║                               ┃
+ *     ┃  ┊       ║        └┈┈┈┈┈>(recv ACK)<┈┈┈┈┈┈┘┃┃             ║                               ┃
+ *     ┃  ┊       V          ┊        V             ┃┃             ║                               ┃
+ *     ┃  ┊  ┌─────────┐     ┊  ┌────────────┐      ┃┃             ║                               ┃
+ *     ┃  ┊  │ CLOSING │     ┊  │ FIN_WAIT_2 │      ┃┃             ║                               ┃
+ *     ┃  ┊  └─────────┘     ┊  └────────────┘      ┃┃        (CMD_DISCON)                         ┃
+ *     ┃  ┊       V          ┊        V            ┌┃┃┈┈┈┈┈┈┈┈<(send FIN)                          ┃
+ *     ┃  ┊       ║          └┈┈┈>(recv FIN)<┈┈┈┈┈┈┘┃┃             ║                               ┃
+ *     ┃  ┊       ║        ┌┈┈┈┈┈<(send ACK)>┈┈┈┈┈┈┐┃┃             V                               ┃
+ *     ┃  └┈┈>(recv ACK)<┈┈┘          ║            ┊┃┃        ┌──────────┐                         ┃
+ *     ┃          ╚════════════════╗  ╚═╗          ┊┃┃        │ LAST_ACK │                         ┃
+ *     ┃ `------,  ,-------'       V    V          ┊┃┃        └──────────┘                         ┃
+ *     ┃         \/             ┌───────────┐      ┊┃┃             V                               ┃
+ *     ┃  Both sides sent       │ TIME_WAIT │      ┊┃┃             ║                               ┃
+ *     ┃  FIN at the "same"     └───────────┘      └┃┃┈┈┈┈┈┈┈┈>(recv ACK)                          ┃
+ *     ┃   time; both are             V             ┃┃             ║                               ┃
+ *     ┃   active closers     (2*MSL has elapsed)   ┃┃             ║                               ┃
+ *     ┃                              ╚═══════════╗ ┃┃  ╔══════════╝                               ┃
+ *     ┣━━━━━━━━━━━━━━━━┓                         V ┃┃  V                         ┏━━━━━━━━━━━━━━━━┫
+ *     ┃ active closer  ┃                       ┌────────┐                        ┃ passive closer ┃
+ *     ┗━━━━━━━━━━━━━━━━┻━━━━━━━━━━━━━━━━━━━━━━━│ CLOSED │━━━━━━━━━━━━━━━━━━━━━━━━┻━━━━━━━━━━━━━━━━┛
  */
-#define _STATUS_TCP_FIN_WAIT   ((uint8_t)0x18) /* during active close */
-#define _STATUS_TCP_CLOSING    ((uint8_t)0x1a) /* during active close */
-#define _STATUS_TCP_TIME_WAIT  ((uint8_t)0x1b) /* during active close */
-#define STATUS_TCP_CLOSE_WAIT  ((uint8_t)0x1c) /* during passive close */
-#define _STATUS_TCP_LAST_ACK   ((uint8_t)0x1d) /* during passive close */
+#define STATE_TCP_INIT        ((uint8_t)0x13)
+#define STATE_TCP_LISTEN      ((uint8_t)0x14) /* server */
+#define STATE_TCP_SYNSENT     ((uint8_t)0x15) /* client; during dial */
+#define STATE_TCP_SYNRECV     ((uint8_t)0x16) /* server; during accept */
+#define STATE_TCP_ESTABLISHED ((uint8_t)0x17)
+#define STATE_TCP_FIN_WAIT    ((uint8_t)0x18) /* during active close */
+#define STATE_TCP_CLOSING     ((uint8_t)0x1a) /* during active close */
+#define STATE_TCP_TIME_WAIT   ((uint8_t)0x1b) /* during active close */
+#define STATE_TCP_CLOSE_WAIT  ((uint8_t)0x1c) /* during passive close */
+#define STATE_TCP_LAST_ACK    ((uint8_t)0x1d) /* during passive close */
 
-#define STATUS_UDP             ((uint8_t)0x22)
+#define STATE_UDP             ((uint8_t)0x22)
 
-#define STATUS_MACRAW          ((uint8_t)0x42)
+#define STATE_MACRAW          ((uint8_t)0x42)
 
 #define REGWRITE_COMMON(spidev, field, val) do {                                      \
 		assert(sizeof(val) == sizeof((struct w5500_block_common_reg).field)); \
@@ -401,7 +419,7 @@ struct libnet_listener *w5500_listen(struct w5500 *chip, uint8_t socknum, uint16
 	REGWRITE_SOCK(chip->spidev, socknum, command, CMD_OPEN);
 	while (REGREAD_SOCK(chip->spidev, socknum, command, uint8_t) != 0x00)
 		cr_yield();
-	while (REGREAD_SOCK(spidev, socknum, status, uint8_t) != STATUS_TCP_INIT)
+	while (REGREAD_SOCK(spidev, socknum, state, uint8_t) != STATE_TCP_INIT)
 		cr_yield();
 
 	return (struct libnet_listener *)&chip->_listeners[socknum];
@@ -425,10 +443,10 @@ static struct libnet_conn *w5500_accept(struct libnet_listener *_self) {
 	while (REGREAD_SOCK(chip->spidev, socknum, command, uint8_t) != 0x00)
 		cr_yield();
 	for (;;) {
-		uint8_t mode = REGREAD_SOCK(spidev, socknum, status, uint8_t);
+		uint8_t mode = REGREAD_SOCK(spidev, socknum, state, uint8_t);
 		switch (mode) {
-		case STATUS_TCP_LISTEN:
-		case _STATUS_TCP_SYNRECV:
+		case STATE_TCP_LISTEN:
+		case STATE_TCP_SYNRECV:
 			cr_yield();
 			break;
 		default:
@@ -464,7 +482,7 @@ static int w5500_close(struct libnet_conn *_self, bool rd, bool wr) {
 	while (REGREAD_SOCK(chip->spidev, socknum, command, uint8_t) != 0x00)
 		cr_yield();
 	REGWRITE_SOCK(chip->spidev, socknum, interrupt, (uint8_t)0xff);
-	while (REGREAD_SOCK(chip->spidev, socknum, status, uint8_t) != STATUS_CLOSED)
+	while (REGREAD_SOCK(chip->spidev, socknum, state, uint8_t) != STATE_CLOSED)
 		cr_yield();
 
 	return 0;