sparc64: vcc: Add RX & TX timer for delayed LDC operation
Add RX & TX timers to perform delayed/asynchronous LDC read and write operations. Signed-off-by: Jagannathan Raman <jag.raman@oracle.com> Reviewed-by: Liam Merwick <liam.merwick@oracle.com> Reviewed-by: Shannon Nelson <shannon.nelson@oracle.com> Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Jag Raman
David S. Miller
parent
8868e44a56
commit
f8c553354e
|
|
@ -1480,6 +1480,7 @@ int ldc_rx_reset(struct ldc_channel *lp)
|
|||
{
|
||||
return __set_rx_head(lp, lp->rx_tail);
|
||||
}
|
||||
EXPORT_SYMBOL(ldc_rx_reset);
|
||||
|
||||
void __ldc_print(struct ldc_channel *lp, const char *caller)
|
||||
{
|
||||
|
|
|
|||
|
|
@ -9,6 +9,7 @@
|
|||
#include <linux/slab.h>
|
||||
#include <linux/sysfs.h>
|
||||
#include <linux/tty.h>
|
||||
#include <linux/tty_flip.h>
|
||||
#include <asm/vio.h>
|
||||
#include <asm/ldc.h>
|
||||
|
||||
|
|
@ -52,6 +53,7 @@ struct vcc_port {
|
|||
|
||||
#define VCC_MAX_PORTS 1024
|
||||
#define VCC_MINOR_START 0 /* must be zero */
|
||||
#define VCC_BUFF_LEN VIO_VCC_MTU_SIZE
|
||||
|
||||
#define VCC_CTL_BREAK -1
|
||||
#define VCC_CTL_HUP -2
|
||||
|
|
@ -256,6 +258,185 @@ static struct vcc_port *vcc_get_ne(unsigned long index)
|
|||
return port;
|
||||
}
|
||||
|
||||
static void vcc_kick_rx(struct vcc_port *port)
|
||||
{
|
||||
struct vio_driver_state *vio = &port->vio;
|
||||
|
||||
assert_spin_locked(&port->lock);
|
||||
|
||||
if (!timer_pending(&port->rx_timer) && !port->removed) {
|
||||
disable_irq_nosync(vio->vdev->rx_irq);
|
||||
port->rx_timer.expires = (jiffies + 1);
|
||||
add_timer(&port->rx_timer);
|
||||
}
|
||||
}
|
||||
|
||||
static void vcc_kick_tx(struct vcc_port *port)
|
||||
{
|
||||
assert_spin_locked(&port->lock);
|
||||
|
||||
if (!timer_pending(&port->tx_timer) && !port->removed) {
|
||||
port->tx_timer.expires = (jiffies + 1);
|
||||
add_timer(&port->tx_timer);
|
||||
}
|
||||
}
|
||||
|
||||
static int vcc_rx_check(struct tty_struct *tty, int size)
|
||||
{
|
||||
if (WARN_ON(!tty || !tty->port))
|
||||
return 1;
|
||||
|
||||
/* tty_buffer_request_room won't sleep because it uses
|
||||
* GFP_ATOMIC flag to allocate buffer
|
||||
*/
|
||||
if (test_bit(TTY_THROTTLED, &tty->flags) ||
|
||||
(tty_buffer_request_room(tty->port, VCC_BUFF_LEN) < VCC_BUFF_LEN))
|
||||
return 0;
|
||||
|
||||
return 1;
|
||||
}
|
||||
|
||||
static int vcc_rx(struct tty_struct *tty, char *buf, int size)
|
||||
{
|
||||
int len = 0;
|
||||
|
||||
if (WARN_ON(!tty || !tty->port))
|
||||
return len;
|
||||
|
||||
len = tty_insert_flip_string(tty->port, buf, size);
|
||||
if (len)
|
||||
tty_flip_buffer_push(tty->port);
|
||||
|
||||
return len;
|
||||
}
|
||||
|
||||
static int vcc_ldc_read(struct vcc_port *port)
|
||||
{
|
||||
struct vio_driver_state *vio = &port->vio;
|
||||
struct tty_struct *tty;
|
||||
struct vio_vcc pkt;
|
||||
int rv = 0;
|
||||
|
||||
tty = port->tty;
|
||||
if (!tty) {
|
||||
rv = ldc_rx_reset(vio->lp);
|
||||
vccdbg("VCC: reset rx q: rv=%d\n", rv);
|
||||
goto done;
|
||||
}
|
||||
|
||||
/* Read as long as LDC has incoming data. */
|
||||
while (1) {
|
||||
if (!vcc_rx_check(tty, VIO_VCC_MTU_SIZE)) {
|
||||
vcc_kick_rx(port);
|
||||
break;
|
||||
}
|
||||
|
||||
vccdbgl(vio->lp);
|
||||
|
||||
rv = ldc_read(vio->lp, &pkt, sizeof(pkt));
|
||||
if (rv <= 0)
|
||||
break;
|
||||
|
||||
vccdbg("VCC: ldc_read()=%d\n", rv);
|
||||
vccdbg("TAG [%02x:%02x:%04x:%08x]\n",
|
||||
pkt.tag.type, pkt.tag.stype,
|
||||
pkt.tag.stype_env, pkt.tag.sid);
|
||||
|
||||
if (pkt.tag.type == VIO_TYPE_DATA) {
|
||||
vccdbgp(pkt);
|
||||
/* vcc_rx_check ensures memory availability */
|
||||
vcc_rx(tty, pkt.data, pkt.tag.stype);
|
||||
} else {
|
||||
pr_err("VCC: unknown msg [%02x:%02x:%04x:%08x]\n",
|
||||
pkt.tag.type, pkt.tag.stype,
|
||||
pkt.tag.stype_env, pkt.tag.sid);
|
||||
rv = -ECONNRESET;
|
||||
break;
|
||||
}
|
||||
|
||||
WARN_ON(rv != LDC_PACKET_SIZE);
|
||||
}
|
||||
|
||||
done:
|
||||
return rv;
|
||||
}
|
||||
|
||||
static void vcc_rx_timer(unsigned long index)
|
||||
{
|
||||
struct vio_driver_state *vio;
|
||||
struct vcc_port *port;
|
||||
unsigned long flags;
|
||||
int rv;
|
||||
|
||||
port = vcc_get_ne(index);
|
||||
if (!port)
|
||||
return;
|
||||
|
||||
spin_lock_irqsave(&port->lock, flags);
|
||||
port->rx_timer.expires = 0;
|
||||
|
||||
vio = &port->vio;
|
||||
|
||||
enable_irq(vio->vdev->rx_irq);
|
||||
|
||||
if (!port->tty || port->removed)
|
||||
goto done;
|
||||
|
||||
rv = vcc_ldc_read(port);
|
||||
if (rv == -ECONNRESET)
|
||||
vio_conn_reset(vio);
|
||||
|
||||
done:
|
||||
spin_unlock_irqrestore(&port->lock, flags);
|
||||
vcc_put(port, false);
|
||||
}
|
||||
|
||||
static void vcc_tx_timer(unsigned long index)
|
||||
{
|
||||
struct vcc_port *port;
|
||||
struct vio_vcc *pkt;
|
||||
unsigned long flags;
|
||||
int tosend = 0;
|
||||
int rv;
|
||||
|
||||
port = vcc_get_ne(index);
|
||||
if (!port)
|
||||
return;
|
||||
|
||||
spin_lock_irqsave(&port->lock, flags);
|
||||
port->tx_timer.expires = 0;
|
||||
|
||||
if (!port->tty || port->removed)
|
||||
goto done;
|
||||
|
||||
tosend = min(VCC_BUFF_LEN, port->chars_in_buffer);
|
||||
if (!tosend)
|
||||
goto done;
|
||||
|
||||
pkt = &port->buffer;
|
||||
pkt->tag.type = VIO_TYPE_DATA;
|
||||
pkt->tag.stype = tosend;
|
||||
vccdbgl(port->vio.lp);
|
||||
|
||||
rv = ldc_write(port->vio.lp, pkt, (VIO_TAG_SIZE + tosend));
|
||||
WARN_ON(!rv);
|
||||
|
||||
if (rv < 0) {
|
||||
vccdbg("VCC: ldc_write()=%d\n", rv);
|
||||
vcc_kick_tx(port);
|
||||
} else {
|
||||
struct tty_struct *tty = port->tty;
|
||||
|
||||
port->chars_in_buffer = 0;
|
||||
if (tty)
|
||||
tty_wakeup(tty);
|
||||
}
|
||||
|
||||
done:
|
||||
spin_unlock_irqrestore(&port->lock, flags);
|
||||
vcc_put(port, false);
|
||||
}
|
||||
|
||||
static void vcc_event(void *arg, int event)
|
||||
{
|
||||
}
|
||||
|
|
@ -322,7 +503,7 @@ static ssize_t vcc_sysfs_break_store(struct device *dev,
|
|||
if (sscanf(buf, "%ud", &brk) != 1 || brk != 1)
|
||||
rv = -EINVAL;
|
||||
else if (vcc_send_ctl(port, VCC_CTL_BREAK) < 0)
|
||||
pr_err("VCC: unable to send CTL_BREAK\n");
|
||||
vcc_kick_tx(port);
|
||||
|
||||
spin_unlock_irqrestore(&port->lock, flags);
|
||||
|
||||
|
|
@ -428,6 +609,14 @@ static int vcc_probe(struct vio_dev *vdev, const struct vio_device_id *id)
|
|||
if (rv)
|
||||
goto free_domain;
|
||||
|
||||
init_timer(&port->rx_timer);
|
||||
port->rx_timer.function = vcc_rx_timer;
|
||||
port->rx_timer.data = port->index;
|
||||
|
||||
init_timer(&port->tx_timer);
|
||||
port->tx_timer.function = vcc_tx_timer;
|
||||
port->tx_timer.data = port->index;
|
||||
|
||||
dev_set_drvdata(&vdev->dev, port);
|
||||
|
||||
/* It's possible to receive IRQs in the middle of vio_port_up. Disable
|
||||
|
|
@ -470,6 +659,9 @@ static int vcc_remove(struct vio_dev *vdev)
|
|||
if (!port)
|
||||
return -ENODEV;
|
||||
|
||||
del_timer_sync(&port->rx_timer);
|
||||
del_timer_sync(&port->tx_timer);
|
||||
|
||||
/* If there's a process with the device open, do a synchronous
|
||||
* hangup of the TTY. This *may* cause the process to call close
|
||||
* asynchronously, but it's not guaranteed.
|
||||
|
|
@ -491,7 +683,6 @@ static int vcc_remove(struct vio_dev *vdev)
|
|||
vio_ldc_free(&port->vio);
|
||||
sysfs_remove_group(&vdev->dev.kobj, &vcc_attribute_group);
|
||||
dev_set_drvdata(&vdev->dev, NULL);
|
||||
|
||||
if (port->tty) {
|
||||
port->removed = true;
|
||||
vcc_put(port, true);
|
||||
|
|
|
|||
Loading…
Reference in New Issue