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authorLinus Torvalds <torvalds@g5.osdl.org>2006-05-12 00:46:42 +0200
committerLinus Torvalds <torvalds@g5.osdl.org>2006-05-12 00:46:42 +0200
commit2bf9d6d0f2dadc2a6c13684719c67dc043b9ce67 (patch)
tree512d855751247641aa68991b11026c1fb48736af
parentMerge master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6 (diff)
parent[SERIAL] 8250: add locking to console write function (diff)
downloadlinux-2bf9d6d0f2dadc2a6c13684719c67dc043b9ce67.tar.xz
linux-2bf9d6d0f2dadc2a6c13684719c67dc043b9ce67.zip
Merge master.kernel.org:/home/rmk/linux-2.6-serial
* master.kernel.org:/home/rmk/linux-2.6-serial: [SERIAL] 8250: add locking to console write function [SERIAL] Remove unconditional enable of TX irq for console [SERIAL] 8250: set divisor register correctly for AMD Alchemy SoC uart [SERIAL] AMD Alchemy UART: claim memory range [SERIAL] Clean up serial locking when obtaining a reference to a port
-rw-r--r--drivers/serial/8250.c74
-rw-r--r--drivers/serial/8250_au1x00.c5
-rw-r--r--drivers/serial/serial_core.c114
-rw-r--r--include/linux/serial_core.h1
4 files changed, 122 insertions, 72 deletions
diff --git a/drivers/serial/8250.c b/drivers/serial/8250.c
index 674b15c78f68..bbf78aaf9e01 100644
--- a/drivers/serial/8250.c
+++ b/drivers/serial/8250.c
@@ -362,6 +362,40 @@ serial_out(struct uart_8250_port *up, int offset, int value)
#define serial_inp(up, offset) serial_in(up, offset)
#define serial_outp(up, offset, value) serial_out(up, offset, value)
+/* Uart divisor latch read */
+static inline int _serial_dl_read(struct uart_8250_port *up)
+{
+ return serial_inp(up, UART_DLL) | serial_inp(up, UART_DLM) << 8;
+}
+
+/* Uart divisor latch write */
+static inline void _serial_dl_write(struct uart_8250_port *up, int value)
+{
+ serial_outp(up, UART_DLL, value & 0xff);
+ serial_outp(up, UART_DLM, value >> 8 & 0xff);
+}
+
+#ifdef CONFIG_SERIAL_8250_AU1X00
+/* Au1x00 haven't got a standard divisor latch */
+static int serial_dl_read(struct uart_8250_port *up)
+{
+ if (up->port.iotype == UPIO_AU)
+ return __raw_readl(up->port.membase + 0x28);
+ else
+ return _serial_dl_read(up);
+}
+
+static void serial_dl_write(struct uart_8250_port *up, int value)
+{
+ if (up->port.iotype == UPIO_AU)
+ __raw_writel(value, up->port.membase + 0x28);
+ else
+ _serial_dl_write(up, value);
+}
+#else
+#define serial_dl_read(up) _serial_dl_read(up)
+#define serial_dl_write(up, value) _serial_dl_write(up, value)
+#endif
/*
* For the 16C950
@@ -494,7 +528,8 @@ static void disable_rsa(struct uart_8250_port *up)
*/
static int size_fifo(struct uart_8250_port *up)
{
- unsigned char old_fcr, old_mcr, old_dll, old_dlm, old_lcr;
+ unsigned char old_fcr, old_mcr, old_lcr;
+ unsigned short old_dl;
int count;
old_lcr = serial_inp(up, UART_LCR);
@@ -505,10 +540,8 @@ static int size_fifo(struct uart_8250_port *up)
UART_FCR_CLEAR_RCVR | UART_FCR_CLEAR_XMIT);
serial_outp(up, UART_MCR, UART_MCR_LOOP);
serial_outp(up, UART_LCR, UART_LCR_DLAB);
- old_dll = serial_inp(up, UART_DLL);
- old_dlm = serial_inp(up, UART_DLM);
- serial_outp(up, UART_DLL, 0x01);
- serial_outp(up, UART_DLM, 0x00);
+ old_dl = serial_dl_read(up);
+ serial_dl_write(up, 0x0001);
serial_outp(up, UART_LCR, 0x03);
for (count = 0; count < 256; count++)
serial_outp(up, UART_TX, count);
@@ -519,8 +552,7 @@ static int size_fifo(struct uart_8250_port *up)
serial_outp(up, UART_FCR, old_fcr);
serial_outp(up, UART_MCR, old_mcr);
serial_outp(up, UART_LCR, UART_LCR_DLAB);
- serial_outp(up, UART_DLL, old_dll);
- serial_outp(up, UART_DLM, old_dlm);
+ serial_dl_write(up, old_dl);
serial_outp(up, UART_LCR, old_lcr);
return count;
@@ -750,8 +782,7 @@ static void autoconfig_16550a(struct uart_8250_port *up)
serial_outp(up, UART_LCR, 0xE0);
- quot = serial_inp(up, UART_DLM) << 8;
- quot += serial_inp(up, UART_DLL);
+ quot = serial_dl_read(up);
quot <<= 3;
status1 = serial_in(up, 0x04); /* EXCR1 */
@@ -759,8 +790,7 @@ static void autoconfig_16550a(struct uart_8250_port *up)
status1 |= 0x10; /* 1.625 divisor for baud_base --> 921600 */
serial_outp(up, 0x04, status1);
- serial_outp(up, UART_DLL, quot & 0xff);
- serial_outp(up, UART_DLM, quot >> 8);
+ serial_dl_write(up, quot);
serial_outp(up, UART_LCR, 0);
@@ -1862,8 +1892,7 @@ serial8250_set_termios(struct uart_port *port, struct termios *termios,
serial_outp(up, UART_LCR, cval | UART_LCR_DLAB);/* set DLAB */
}
- serial_outp(up, UART_DLL, quot & 0xff); /* LS of divisor */
- serial_outp(up, UART_DLM, quot >> 8); /* MS of divisor */
+ serial_dl_write(up, quot);
/*
* LCR DLAB must be set to enable 64-byte FIFO mode. If the FCR
@@ -1906,6 +1935,9 @@ static int serial8250_request_std_resource(struct uart_8250_port *up)
int ret = 0;
switch (up->port.iotype) {
+ case UPIO_AU:
+ size = 0x100000;
+ /* fall thru */
case UPIO_MEM:
if (!up->port.mapbase)
break;
@@ -1938,6 +1970,9 @@ static void serial8250_release_std_resource(struct uart_8250_port *up)
unsigned int size = 8 << up->port.regshift;
switch (up->port.iotype) {
+ case UPIO_AU:
+ size = 0x100000;
+ /* fall thru */
case UPIO_MEM:
if (!up->port.mapbase)
break;
@@ -2200,10 +2235,17 @@ static void
serial8250_console_write(struct console *co, const char *s, unsigned int count)
{
struct uart_8250_port *up = &serial8250_ports[co->index];
+ unsigned long flags;
unsigned int ier;
+ int locked = 1;
touch_nmi_watchdog();
+ if (oops_in_progress) {
+ locked = spin_trylock_irqsave(&up->port.lock, flags);
+ } else
+ spin_lock_irqsave(&up->port.lock, flags);
+
/*
* First save the IER then disable the interrupts
*/
@@ -2221,8 +2263,10 @@ serial8250_console_write(struct console *co, const char *s, unsigned int count)
* and restore the IER
*/
wait_for_xmitr(up, BOTH_EMPTY);
- up->ier |= UART_IER_THRI;
- serial_out(up, UART_IER, ier | UART_IER_THRI);
+ serial_out(up, UART_IER, ier);
+
+ if (locked)
+ spin_unlock_irqrestore(&up->port.lock, flags);
}
static int serial8250_console_setup(struct console *co, char *options)
diff --git a/drivers/serial/8250_au1x00.c b/drivers/serial/8250_au1x00.c
index 3d1bfd07208d..58015fd14be9 100644
--- a/drivers/serial/8250_au1x00.c
+++ b/drivers/serial/8250_au1x00.c
@@ -30,13 +30,12 @@
{ \
.iobase = _base, \
.membase = (void __iomem *)_base,\
- .mapbase = _base, \
+ .mapbase = CPHYSADDR(_base), \
.irq = _irq, \
.uartclk = 0, /* filled */ \
.regshift = 2, \
.iotype = UPIO_AU, \
- .flags = UPF_SKIP_TEST | \
- UPF_IOREMAP, \
+ .flags = UPF_SKIP_TEST \
}
static struct plat_serial8250_port au1x00_data[] = {
diff --git a/drivers/serial/serial_core.c b/drivers/serial/serial_core.c
index fcd7744c4253..aeb8153ccf24 100644
--- a/drivers/serial/serial_core.c
+++ b/drivers/serial/serial_core.c
@@ -1500,20 +1500,18 @@ uart_block_til_ready(struct file *filp, struct uart_state *state)
static struct uart_state *uart_get(struct uart_driver *drv, int line)
{
struct uart_state *state;
+ int ret = 0;
- mutex_lock(&port_mutex);
state = drv->state + line;
if (mutex_lock_interruptible(&state->mutex)) {
- state = ERR_PTR(-ERESTARTSYS);
- goto out;
+ ret = -ERESTARTSYS;
+ goto err;
}
state->count++;
- if (!state->port) {
- state->count--;
- mutex_unlock(&state->mutex);
- state = ERR_PTR(-ENXIO);
- goto out;
+ if (!state->port || state->port->flags & UPF_DEAD) {
+ ret = -ENXIO;
+ goto err_unlock;
}
if (!state->info) {
@@ -1531,15 +1529,17 @@ static struct uart_state *uart_get(struct uart_driver *drv, int line)
tasklet_init(&state->info->tlet, uart_tasklet_action,
(unsigned long)state);
} else {
- state->count--;
- mutex_unlock(&state->mutex);
- state = ERR_PTR(-ENOMEM);
+ ret = -ENOMEM;
+ goto err_unlock;
}
}
-
- out:
- mutex_unlock(&port_mutex);
return state;
+
+ err_unlock:
+ state->count--;
+ mutex_unlock(&state->mutex);
+ err:
+ return ERR_PTR(ret);
}
/*
@@ -2085,45 +2085,6 @@ uart_configure_port(struct uart_driver *drv, struct uart_state *state,
}
}
-/*
- * This reverses the effects of uart_configure_port, hanging up the
- * port before removal.
- */
-static void
-uart_unconfigure_port(struct uart_driver *drv, struct uart_state *state)
-{
- struct uart_port *port = state->port;
- struct uart_info *info = state->info;
-
- if (info && info->tty)
- tty_vhangup(info->tty);
-
- mutex_lock(&state->mutex);
-
- state->info = NULL;
-
- /*
- * Free the port IO and memory resources, if any.
- */
- if (port->type != PORT_UNKNOWN)
- port->ops->release_port(port);
-
- /*
- * Indicate that there isn't a port here anymore.
- */
- port->type = PORT_UNKNOWN;
-
- /*
- * Kill the tasklet, and free resources.
- */
- if (info) {
- tasklet_kill(&info->tlet);
- kfree(info);
- }
-
- mutex_unlock(&state->mutex);
-}
-
static struct tty_operations uart_ops = {
.open = uart_open,
.close = uart_close,
@@ -2270,6 +2231,7 @@ int uart_add_one_port(struct uart_driver *drv, struct uart_port *port)
state = drv->state + port->line;
mutex_lock(&port_mutex);
+ mutex_lock(&state->mutex);
if (state->port) {
ret = -EINVAL;
goto out;
@@ -2304,7 +2266,13 @@ int uart_add_one_port(struct uart_driver *drv, struct uart_port *port)
port->cons && !(port->cons->flags & CON_ENABLED))
register_console(port->cons);
+ /*
+ * Ensure UPF_DEAD is not set.
+ */
+ port->flags &= ~UPF_DEAD;
+
out:
+ mutex_unlock(&state->mutex);
mutex_unlock(&port_mutex);
return ret;
@@ -2322,6 +2290,7 @@ int uart_add_one_port(struct uart_driver *drv, struct uart_port *port)
int uart_remove_one_port(struct uart_driver *drv, struct uart_port *port)
{
struct uart_state *state = drv->state + port->line;
+ struct uart_info *info;
BUG_ON(in_interrupt());
@@ -2332,11 +2301,48 @@ int uart_remove_one_port(struct uart_driver *drv, struct uart_port *port)
mutex_lock(&port_mutex);
/*
+ * Mark the port "dead" - this prevents any opens from
+ * succeeding while we shut down the port.
+ */
+ mutex_lock(&state->mutex);
+ port->flags |= UPF_DEAD;
+ mutex_unlock(&state->mutex);
+
+ /*
* Remove the devices from devfs
*/
tty_unregister_device(drv->tty_driver, port->line);
- uart_unconfigure_port(drv, state);
+ info = state->info;
+ if (info && info->tty)
+ tty_vhangup(info->tty);
+
+ /*
+ * All users of this port should now be disconnected from
+ * this driver, and the port shut down. We should be the
+ * only thread fiddling with this port from now on.
+ */
+ state->info = NULL;
+
+ /*
+ * Free the port IO and memory resources, if any.
+ */
+ if (port->type != PORT_UNKNOWN)
+ port->ops->release_port(port);
+
+ /*
+ * Indicate that there isn't a port here anymore.
+ */
+ port->type = PORT_UNKNOWN;
+
+ /*
+ * Kill the tasklet, and free resources.
+ */
+ if (info) {
+ tasklet_kill(&info->tlet);
+ kfree(info);
+ }
+
state->port = NULL;
mutex_unlock(&port_mutex);
diff --git a/include/linux/serial_core.h b/include/linux/serial_core.h
index c32e60e79dea..bd14858121ea 100644
--- a/include/linux/serial_core.h
+++ b/include/linux/serial_core.h
@@ -254,6 +254,7 @@ struct uart_port {
#define UPF_CONS_FLOW ((__force upf_t) (1 << 23))
#define UPF_SHARE_IRQ ((__force upf_t) (1 << 24))
#define UPF_BOOT_AUTOCONF ((__force upf_t) (1 << 28))
+#define UPF_DEAD ((__force upf_t) (1 << 30))
#define UPF_IOREMAP ((__force upf_t) (1 << 31))
#define UPF_CHANGE_MASK ((__force upf_t) (0x17fff))