X-Git-Url: http://git.onelab.eu/?a=blobdiff_plain;f=drivers%2Fchar%2Fhvsi.c;h=d7806834fc171ad07f08c90f0e5b20a30c000987;hb=97bf2856c6014879bd04983a3e9dfcdac1e7fe85;hp=595079c07be541edff08da5b86286dabd4f420e6;hpb=a2c21200f1c81b08cb55e417b68150bba439b646;p=linux-2.6.git

diff --git a/drivers/char/hvsi.c b/drivers/char/hvsi.c
index 595079c07..d7806834f 100644
--- a/drivers/char/hvsi.c
+++ b/drivers/char/hvsi.c
@@ -29,11 +29,6 @@
  * the OS cannot change the speed of the port through this protocol.
  */
 
-/* TODO:
- * test FSP reset
- * add udbg support for xmon/kdb
- */
-
 #undef DEBUG
 
 #include <linux/console.h>
@@ -54,6 +49,7 @@
 #include <asm/prom.h>
 #include <asm/uaccess.h>
 #include <asm/vio.h>
+#include <asm/param.h>
 
 #define HVSI_MAJOR	229
 #define HVSI_MINOR	128
@@ -73,7 +69,8 @@
 #define __ALIGNED__	__attribute__((__aligned__(sizeof(long))))
 
 struct hvsi_struct {
-	struct work_struct writer;
+	struct delayed_work writer;
+	struct work_struct handshaker;
 	wait_queue_head_t emptyq; /* woken when outbuf is emptied */
 	wait_queue_head_t stateq; /* woken when HVSI state changes */
 	spinlock_t lock;
@@ -109,6 +106,7 @@ enum HVSI_PROTOCOL_STATE {
 	HVSI_WAIT_FOR_VER_QUERY,
 	HVSI_OPEN,
 	HVSI_WAIT_FOR_MCTRL_RESPONSE,
+	HVSI_FSP_DIED,
 };
 #define HVSI_CONSOLE 0x1
 
@@ -172,6 +170,13 @@ struct hvsi_query_response {
 	} u;
 } __attribute__((packed));
 
+
+
+static inline int is_console(struct hvsi_struct *hp)
+{
+	return hp->flags & HVSI_CONSOLE;
+}
+
 static inline int is_open(struct hvsi_struct *hp)
 {
 	/* if we're waiting for an mctrl then we're already open */
@@ -188,10 +193,11 @@ static inline void print_state(struct hvsi_struct *hp)
 		"HVSI_WAIT_FOR_VER_QUERY",
 		"HVSI_OPEN",
 		"HVSI_WAIT_FOR_MCTRL_RESPONSE",
+		"HVSI_FSP_DIED",
 	};
 	const char *name = state_names[hp->state];
 
-	if (hp->state > (sizeof(state_names)/sizeof(char*)))
+	if (hp->state > ARRAY_SIZE(state_names))
 		name = "UNKNOWN";
 
 	pr_debug("hvsi%i: state = %s\n", hp->index, name);
@@ -285,25 +291,18 @@ static void dump_packet(uint8_t *packet)
 	dump_hex(packet, header->len);
 }
 
-/* can't use hvc_get_chars because that strips CRs */
 static int hvsi_read(struct hvsi_struct *hp, char *buf, int count)
 {
 	unsigned long got;
 
-	if (plpar_hcall(H_GET_TERM_CHAR, hp->vtermno, 0, 0, 0, &got,
-			(unsigned long *)buf, (unsigned long *)buf+1) == H_Success)
-		return got;
-	return 0;
+	got = hvc_get_chars(hp->vtermno, buf, count);
+
+	return got;
 }
 
-/*
- * we can't call tty_hangup() directly here because we need to call that
- * outside of our lock
- */
-static struct tty_struct *hvsi_recv_control(struct hvsi_struct *hp,
-		uint8_t *packet)
+static void hvsi_recv_control(struct hvsi_struct *hp, uint8_t *packet,
+	struct tty_struct **to_hangup, struct hvsi_struct **to_handshake)
 {
-	struct tty_struct *to_hangup = NULL;
 	struct hvsi_control *header = (struct hvsi_control *)packet;
 
 	switch (header->verb) {
@@ -312,16 +311,16 @@ static struct tty_struct *hvsi_recv_control(struct hvsi_struct *hp,
 				/* CD went away; no more connection */
 				pr_debug("hvsi%i: CD dropped\n", hp->index);
 				hp->mctrl &= TIOCM_CD;
-				if (!(hp->tty->flags & CLOCAL))
-					to_hangup = hp->tty;
+				/* If userland hasn't done an open(2) yet, hp->tty is NULL. */
+				if (hp->tty && !(hp->tty->flags & CLOCAL))
+					*to_hangup = hp->tty;
 			}
 			break;
 		case VSV_CLOSE_PROTOCOL:
-			printk(KERN_DEBUG
-				"hvsi%i: service processor closed connection!\n", hp->index);
-			__set_state(hp, HVSI_CLOSED);
-			to_hangup = hp->tty;
-			hp->tty = NULL;
+			pr_debug("hvsi%i: service processor came back\n", hp->index);
+			if (hp->state != HVSI_CLOSED) {
+				*to_handshake = hp;
+			}
 			break;
 		default:
 			printk(KERN_WARNING "hvsi%i: unknown HVSI control packet: ",
@@ -329,8 +328,6 @@ static struct tty_struct *hvsi_recv_control(struct hvsi_struct *hp,
 			dump_packet(packet);
 			break;
 	}
-
-	return to_hangup;
 }
 
 static void hvsi_recv_response(struct hvsi_struct *hp, uint8_t *packet)
@@ -388,8 +385,8 @@ static void hvsi_recv_query(struct hvsi_struct *hp, uint8_t *packet)
 
 	switch (hp->state) {
 		case HVSI_WAIT_FOR_VER_QUERY:
-			__set_state(hp, HVSI_OPEN);
 			hvsi_version_respond(hp, query->seqno);
+			__set_state(hp, HVSI_OPEN);
 			break;
 		default:
 			printk(KERN_ERR "hvsi%i: unexpected query: ", hp->index);
@@ -409,7 +406,7 @@ static void hvsi_insert_chars(struct hvsi_struct *hp, const char *buf, int len)
 			hp->sysrq = 1;
 			continue;
 		} else if (hp->sysrq) {
-			handle_sysrq(c, NULL, hp->tty);
+			handle_sysrq(c, hp->tty);
 			hp->sysrq = 0;
 			continue;
 		}
@@ -467,17 +464,20 @@ static struct tty_struct *hvsi_recv_data(struct hvsi_struct *hp,
  * incoming data).
  */
 static int hvsi_load_chunk(struct hvsi_struct *hp, struct tty_struct **flip,
-		struct tty_struct **hangup)
+		struct tty_struct **hangup, struct hvsi_struct **handshake)
 {
 	uint8_t *packet = hp->inbuf;
 	int chunklen;
 
 	*flip = NULL;
 	*hangup = NULL;
+	*handshake = NULL;
 
 	chunklen = hvsi_read(hp, hp->inbuf_end, HVSI_MAX_READ);
-	if (chunklen == 0)
+	if (chunklen == 0) {
+		pr_debug("%s: 0-length read\n", __FUNCTION__);
 		return 0;
+	}
 
 	pr_debug("%s: got %i bytes\n", __FUNCTION__, chunklen);
 	dbg_dump_hex(hp->inbuf_end, chunklen);
@@ -509,7 +509,7 @@ static int hvsi_load_chunk(struct hvsi_struct *hp, struct tty_struct **flip,
 				*flip = hvsi_recv_data(hp, packet);
 				break;
 			case VS_CONTROL_PACKET_HEADER:
-				*hangup = hvsi_recv_control(hp, packet);
+				hvsi_recv_control(hp, packet, hangup, handshake);
 				break;
 			case VS_QUERY_RESPONSE_PACKET_HEADER:
 				hvsi_recv_response(hp, packet);
@@ -526,8 +526,8 @@ static int hvsi_load_chunk(struct hvsi_struct *hp, struct tty_struct **flip,
 
 		packet += len_packet(packet);
 
-		if (*hangup) {
-			pr_debug("%s: hangup\n", __FUNCTION__);
+		if (*hangup || *handshake) {
+			pr_debug("%s: hangup or handshake\n", __FUNCTION__);
 			/*
 			 * we need to send the hangup now before receiving any more data.
 			 * If we get "data, hangup, data", we can't deliver the second
@@ -555,21 +555,20 @@ static void hvsi_send_overflow(struct hvsi_struct *hp)
  * must get all pending data because we only get an irq on empty->non-empty
  * transition
  */
-static irqreturn_t hvsi_interrupt(int irq, void *arg, struct pt_regs *regs)
+static irqreturn_t hvsi_interrupt(int irq, void *arg)
 {
 	struct hvsi_struct *hp = (struct hvsi_struct *)arg;
 	struct tty_struct *flip;
 	struct tty_struct *hangup;
+	struct hvsi_struct *handshake;
 	unsigned long flags;
-	irqreturn_t handled = IRQ_NONE;
 	int again = 1;
 
 	pr_debug("%s\n", __FUNCTION__);
 
 	while (again) {
 		spin_lock_irqsave(&hp->lock, flags);
-		again = hvsi_load_chunk(hp, &flip, &hangup);
-		handled = IRQ_HANDLED;
+		again = hvsi_load_chunk(hp, &flip, &hangup, &handshake);
 		spin_unlock_irqrestore(&hp->lock, flags);
 
 		/*
@@ -587,6 +586,11 @@ static irqreturn_t hvsi_interrupt(int irq, void *arg, struct pt_regs *regs)
 		if (hangup) {
 			tty_hangup(hangup);
 		}
+
+		if (handshake) {
+			pr_debug("hvsi%i: attempting re-handshake\n", handshake->index);
+			schedule_work(&handshake->handshaker);
+		}
 	}
 
 	spin_lock_irqsave(&hp->lock, flags);
@@ -603,7 +607,7 @@ static irqreturn_t hvsi_interrupt(int irq, void *arg, struct pt_regs *regs)
 		tty_flip_buffer_push(flip);
 	}
 
-	return handled;
+	return IRQ_HANDLED;
 }
 
 /* for boot console, before the irq handler is running */
@@ -612,7 +616,7 @@ static int __init poll_for_state(struct hvsi_struct *hp, int state)
 	unsigned long end_jiffies = jiffies + HVSI_TIMEOUT;
 
 	for (;;) {
-		hvsi_interrupt(hp->virq, (void *)hp, NULL); /* get pending data */
+		hvsi_interrupt(hp->virq, (void *)hp); /* get pending data */
 
 		if (hp->state == state)
 			return 0;
@@ -626,27 +630,10 @@ static int __init poll_for_state(struct hvsi_struct *hp, int state)
 /* wait for irq handler to change our state */
 static int wait_for_state(struct hvsi_struct *hp, int state)
 {
-	unsigned long end_jiffies = jiffies + HVSI_TIMEOUT;
-	unsigned long timeout;
 	int ret = 0;
 
-	DECLARE_WAITQUEUE(myself, current);
-	set_current_state(TASK_INTERRUPTIBLE);
-	add_wait_queue(&hp->stateq, &myself);
-
-	for (;;) {
-		set_current_state(TASK_INTERRUPTIBLE);
-		if (hp->state == state)
-			break;
-		timeout = end_jiffies - jiffies;
-		if (time_after(jiffies, end_jiffies)) {
-			ret = -EIO;
-			break;
-		}
-		schedule_timeout(timeout);
-	}
-	remove_wait_queue(&hp->stateq, &myself);
-	set_current_state(TASK_RUNNING);
+	if (!wait_event_timeout(hp->stateq, (hp->state == state), HVSI_TIMEOUT))
+		ret = -EIO;
 
 	return ret;
 }
@@ -757,6 +744,24 @@ static int hvsi_handshake(struct hvsi_struct *hp)
 	return 0;
 }
 
+static void hvsi_handshaker(struct work_struct *work)
+{
+	struct hvsi_struct *hp =
+		container_of(work, struct hvsi_struct, handshaker);
+
+	if (hvsi_handshake(hp) >= 0)
+		return;
+
+	printk(KERN_ERR "hvsi%i: re-handshaking failed\n", hp->index);
+	if (is_console(hp)) {
+		/*
+		 * ttys will re-attempt the handshake via hvsi_open, but
+		 * the console will not.
+		 */
+		printk(KERN_ERR "hvsi%i: lost console!\n", hp->index);
+	}
+}
+
 static int hvsi_put_chars(struct hvsi_struct *hp, const char *buf, int count)
 {
 	struct hvsi_data packet __ALIGNED__;
@@ -808,6 +813,10 @@ static int hvsi_open(struct tty_struct *tty, struct file *filp)
 	tty->driver_data = hp;
 	tty->low_latency = 1; /* avoid throttle/tty_flip_buffer_push race */
 
+	mb();
+	if (hp->state == HVSI_FSP_DIED)
+		return -EIO;
+
 	spin_lock_irqsave(&hp->lock, flags);
 	hp->tty = tty;
 	hp->count++;
@@ -815,7 +824,7 @@ static int hvsi_open(struct tty_struct *tty, struct file *filp)
 	h_vio_signal(hp->vtermno, VIO_IRQ_ENABLE);
 	spin_unlock_irqrestore(&hp->lock, flags);
 
-	if (hp->flags & HVSI_CONSOLE)
+	if (is_console(hp))
 		return 0; /* this has already been handshaked as the console */
 
 	ret = hvsi_handshake(hp);
@@ -842,24 +851,7 @@ static int hvsi_open(struct tty_struct *tty, struct file *filp)
 /* wait for hvsi_write_worker to empty hp->outbuf */
 static void hvsi_flush_output(struct hvsi_struct *hp)
 {
-	unsigned long end_jiffies = jiffies + HVSI_TIMEOUT;
-	unsigned long timeout;
-
-	DECLARE_WAITQUEUE(myself, current);
-	set_current_state(TASK_UNINTERRUPTIBLE);
-	add_wait_queue(&hp->emptyq, &myself);
-
-	for (;;) {
-		set_current_state(TASK_UNINTERRUPTIBLE);
-		if (hp->n_outbuf <= 0)
-			break;
-		timeout = end_jiffies - jiffies;
-		if (time_after(jiffies, end_jiffies))
-			break;
-		schedule_timeout(timeout);
-	}
-	remove_wait_queue(&hp->emptyq, &myself);
-	set_current_state(TASK_RUNNING);
+	wait_event_timeout(hp->emptyq, (hp->n_outbuf <= 0), HVSI_TIMEOUT);
 
 	/* 'writer' could still be pending if it didn't see n_outbuf = 0 yet */
 	cancel_delayed_work(&hp->writer);
@@ -889,7 +881,7 @@ static void hvsi_close(struct tty_struct *tty, struct file *filp)
 		hp->inbuf_end = hp->inbuf; /* discard remaining partial packets */
 
 		/* only close down connection if it is not the console */
-		if (!(hp->flags & HVSI_CONSOLE)) {
+		if (!is_console(hp)) {
 			h_vio_signal(hp->vtermno, VIO_IRQ_DISABLE); /* no more irqs */
 			__set_state(hp, HVSI_CLOSED);
 			/*
@@ -927,11 +919,17 @@ static void hvsi_close(struct tty_struct *tty, struct file *filp)
 static void hvsi_hangup(struct tty_struct *tty)
 {
 	struct hvsi_struct *hp = tty->driver_data;
+	unsigned long flags;
 
 	pr_debug("%s\n", __FUNCTION__);
 
+	spin_lock_irqsave(&hp->lock, flags);
+
 	hp->count = 0;
+	hp->n_outbuf = 0;
 	hp->tty = NULL;
+
+	spin_unlock_irqrestore(&hp->lock, flags);
 }
 
 /* called with hp->lock held */
@@ -943,19 +941,21 @@ static void hvsi_push(struct hvsi_struct *hp)
 		return;
 
 	n = hvsi_put_chars(hp, hp->outbuf, hp->n_outbuf);
-	if (n != 0) {
-		/*
-		 * either all data was sent or there was an error, and we throw away
-		 * data on error.
-		 */
+	if (n > 0) {
+		/* success */
+		pr_debug("%s: wrote %i chars\n", __FUNCTION__, n);
 		hp->n_outbuf = 0;
+	} else if (n == -EIO) {
+		__set_state(hp, HVSI_FSP_DIED);
+		printk(KERN_ERR "hvsi%i: service processor died\n", hp->index);
 	}
 }
 
 /* hvsi_write_worker will keep rescheduling itself until outbuf is empty */
-static void hvsi_write_worker(void *arg)
+static void hvsi_write_worker(struct work_struct *work)
 {
-	struct hvsi_struct *hp = (struct hvsi_struct *)arg;
+	struct hvsi_struct *hp =
+		container_of(work, struct hvsi_struct, writer.work);
 	unsigned long flags;
 #ifdef DEBUG
 	static long start_j = 0;
@@ -966,6 +966,19 @@ static void hvsi_write_worker(void *arg)
 
 	spin_lock_irqsave(&hp->lock, flags);
 
+	pr_debug("%s: %i chars in buffer\n", __FUNCTION__, hp->n_outbuf);
+
+	if (!is_open(hp)) {
+		/*
+		 * We could have a non-open connection if the service processor died
+		 * while we were busily scheduling ourselves. In that case, it could
+		 * be minutes before the service processor comes back, so only try
+		 * again once a second.
+		 */
+		schedule_delayed_work(&hp->writer, HZ);
+		goto out;
+	}
+
 	hvsi_push(hp);
 	if (hp->n_outbuf > 0)
 		schedule_delayed_work(&hp->writer, 10);
@@ -976,12 +989,10 @@ static void hvsi_write_worker(void *arg)
 		start_j = 0;
 #endif /* DEBUG */
 		wake_up_all(&hp->emptyq);
-		if (test_bit(TTY_DO_WRITE_WAKEUP, &hp->tty->flags)
-				&& hp->tty->ldisc.write_wakeup)
-			hp->tty->ldisc.write_wakeup(hp->tty);
-		wake_up_interruptible(&hp->tty->write_wait);
+		tty_wakeup(hp->tty);
 	}
 
+out:
 	spin_unlock_irqrestore(&hp->lock, flags);
 }
 
@@ -999,29 +1010,19 @@ static int hvsi_chars_in_buffer(struct tty_struct *tty)
 	return hp->n_outbuf;
 }
 
-static int hvsi_write(struct tty_struct *tty, int from_user,
+static int hvsi_write(struct tty_struct *tty,
 		     const unsigned char *buf, int count)
 {
 	struct hvsi_struct *hp = tty->driver_data;
 	const char *source = buf;
-	char *kbuf = NULL;
 	unsigned long flags;
 	int total = 0;
 	int origcount = count;
 
-	if (from_user) {
-		kbuf = kmalloc(count, GFP_KERNEL);
-		if (kbuf == NULL)
-			return -ENOMEM;
-		if (copy_from_user(kbuf, buf, count)) {
-			kfree(kbuf);
-			return -EFAULT;
-		}
-		source = kbuf;
-	}
-
 	spin_lock_irqsave(&hp->lock, flags);
 
+	pr_debug("%s: %i chars in buffer\n", __FUNCTION__, hp->n_outbuf);
+
 	if (!is_open(hp)) {
 		/* we're either closing or not yet open; don't accept data */
 		pr_debug("%s: not open\n", __FUNCTION__);
@@ -1057,9 +1058,6 @@ static int hvsi_write(struct tty_struct *tty, int from_user,
 out:
 	spin_unlock_irqrestore(&hp->lock, flags);
 
-	if (from_user)
-		kfree(kbuf);
-
 	if (total != origcount)
 		pr_debug("%s: wanted %i, only wrote %i\n", __FUNCTION__, origcount,
 			total);
@@ -1134,7 +1132,7 @@ static int hvsi_tiocmset(struct tty_struct *tty, struct file *file,
 }
 
 
-static struct tty_operations hvsi_ops = {
+static const struct tty_operations hvsi_ops = {
 	.open = hvsi_open,
 	.close = hvsi_close,
 	.write = hvsi_write,
@@ -1156,7 +1154,6 @@ static int __init hvsi_init(void)
 		return -ENOMEM;
 
 	hvsi_driver->owner = THIS_MODULE;
-	hvsi_driver->devfs_name = "hvsi/";
 	hvsi_driver->driver_name = "hvsi";
 	hvsi_driver->name = "hvsi";
 	hvsi_driver->major = HVSI_MAJOR;
@@ -1164,6 +1161,8 @@ static int __init hvsi_init(void)
 	hvsi_driver->type = TTY_DRIVER_TYPE_SYSTEM;
 	hvsi_driver->init_termios = tty_std_termios;
 	hvsi_driver->init_termios.c_cflag = B9600 | CS8 | CREAD | HUPCL;
+	hvsi_driver->init_termios.c_ispeed = 9600;
+	hvsi_driver->init_termios.c_ospeed = 9600;
 	hvsi_driver->flags = TTY_DRIVER_REAL_RAW;
 	tty_set_operations(hvsi_driver, &hvsi_ops);
 
@@ -1171,7 +1170,7 @@ static int __init hvsi_init(void)
 		struct hvsi_struct *hp = &hvsi_ports[i];
 		int ret = 1;
 
-		ret = request_irq(hp->virq, hvsi_interrupt, SA_INTERRUPT, "hvsi", hp);
+		ret = request_irq(hp->virq, hvsi_interrupt, IRQF_DISABLED, "hvsi", hp);
 		if (ret)
 			printk(KERN_ERR "HVSI: couldn't reserve irq 0x%x (error %i)\n",
 				hp->virq, ret);
@@ -1181,7 +1180,7 @@ static int __init hvsi_init(void)
 	if (tty_register_driver(hvsi_driver))
 		panic("Couldn't register hvsi console driver\n");
 
-	printk(KERN_INFO "HVSI: registered %i devices\n", hvsi_count);
+	printk(KERN_DEBUG "HVSI: registered %i devices\n", hvsi_count);
 
 	return 0;
 }
@@ -1279,11 +1278,10 @@ static int __init hvsi_console_init(void)
 			vty != NULL;
 			vty = of_find_compatible_node(vty, "serial", "hvterm-protocol")) {
 		struct hvsi_struct *hp;
-		uint32_t *vtermno;
-		uint32_t *irq;
+		const uint32_t *vtermno, *irq;
 
-		vtermno = (uint32_t *)get_property(vty, "reg", NULL);
-		irq = (uint32_t *)get_property(vty, "interrupts", NULL);
+		vtermno = get_property(vty, "reg", NULL);
+		irq = get_property(vty, "interrupts", NULL);
 		if (!vtermno || !irq)
 			continue;
 
@@ -1293,21 +1291,21 @@ static int __init hvsi_console_init(void)
 		}
 
 		hp = &hvsi_ports[hvsi_count];
-		INIT_WORK(&hp->writer, hvsi_write_worker, hp);
+		INIT_DELAYED_WORK(&hp->writer, hvsi_write_worker);
+		INIT_WORK(&hp->handshaker, hvsi_handshaker);
 		init_waitqueue_head(&hp->emptyq);
 		init_waitqueue_head(&hp->stateq);
-		hp->lock = SPIN_LOCK_UNLOCKED;
+		spin_lock_init(&hp->lock);
 		hp->index = hvsi_count;
 		hp->inbuf_end = hp->inbuf;
 		hp->state = HVSI_CLOSED;
 		hp->vtermno = *vtermno;
-		hp->virq = virt_irq_create_mapping(irq[0]);
+		hp->virq = irq_create_mapping(NULL, irq[0]);
 		if (hp->virq == NO_IRQ) {
 			printk(KERN_ERR "%s: couldn't create irq mapping for 0x%x\n",
-				__FUNCTION__, hp->virq);
+				__FUNCTION__, irq[0]);
 			continue;
-		} else
-			hp->virq = irq_offset_up(hp->virq);
+		}
 
 		hvsi_count++;
 	}