diff --git a/arch/mn10300/kernel/asm-offsets.c b/arch/mn10300/kernel/asm-offsets.c
index 96f24fab7de6ee0e559369e195a2fa7b5120a8f2..47b3bb0c04ffc4f9db8395a6042235a5c7fab105 100644
--- a/arch/mn10300/kernel/asm-offsets.c
+++ b/arch/mn10300/kernel/asm-offsets.c
@@ -96,7 +96,7 @@ void foo(void)
OFFSET(__rx_outp, mn10300_serial_port, rx_outp);
OFFSET(__uart_state, mn10300_serial_port, uart.state);
OFFSET(__tx_xchar, mn10300_serial_port, tx_xchar);
- OFFSET(__tx_break, mn10300_serial_port, tx_break);
+ OFFSET(__tx_flags, mn10300_serial_port, tx_flags);
OFFSET(__intr_flags, mn10300_serial_port, intr_flags);
OFFSET(__rx_icr, mn10300_serial_port, rx_icr);
OFFSET(__tx_icr, mn10300_serial_port, tx_icr);
diff --git a/arch/mn10300/kernel/mn10300-serial-low.S b/arch/mn10300/kernel/mn10300-serial-low.S
index dfc1b6f2fa9a4b70f251d8766c773c39fc7733fe..b95e76caf4fae24e0841500cde288bcd775dbc5f 100644
--- a/arch/mn10300/kernel/mn10300-serial-low.S
+++ b/arch/mn10300/kernel/mn10300-serial-low.S
@@ -118,8 +118,8 @@ ENTRY(mn10300_serial_vdma_tx_handler)
movbu d2,(e3) # ACK the interrupt
movhu (e3),d2 # flush
- btst 0x01,(__tx_break,a3) # handle transmit break request
- bne mnsc_vdma_tx_break
+ btst 0xFF,(__tx_flags,a3) # handle transmit flags
+ bne mnsc_vdma_tx_flags
movbu (SCxSTR,e2),d2 # don't try and transmit a char if the
# buffer is not empty
@@ -171,10 +171,13 @@ mnsc_vdma_tx_empty:
bset MNSCx_TX_EMPTY,(__intr_flags,a3)
bra mnsc_vdma_tx_done
-mnsc_vdma_tx_break:
+mnsc_vdma_tx_flags:
+ btst MNSCx_TX_STOP,(__tx_flags,a3)
+ bne mnsc_vdma_tx_stop
movhu (SCxCTR,e2),d2 # turn on break mode
or SC01CTR_BKE,d2
movhu d2,(SCxCTR,e2)
+mnsc_vdma_tx_stop:
mov +(NUM2GxICR_LEVEL(CONFIG_MN10300_SERIAL_IRQ_LEVEL)|GxICR_DETECT),d2
movhu d2,(e3) # disable transmit interrupts on this
# channel
diff --git a/arch/mn10300/kernel/mn10300-serial.c b/arch/mn10300/kernel/mn10300-serial.c
index cac0f0da92037e3cd9fe61d9e5b063d0b23d2670..587545cb7e4c82ed3884928f148fed445a784259 100644
--- a/arch/mn10300/kernel/mn10300-serial.c
+++ b/arch/mn10300/kernel/mn10300-serial.c
@@ -444,25 +444,53 @@ struct mn10300_serial_int mn10300_serial_int_tbl[NR_IRQS];
static void mn10300_serial_dis_tx_intr(struct mn10300_serial_port *port)
{
- unsigned long flags;
+ int retries = 100;
u16 x;
- flags = arch_local_cli_save();
- *port->tx_icr = NUM2GxICR_LEVEL(CONFIG_MN10300_SERIAL_IRQ_LEVEL);
- x = *port->tx_icr;
- arch_local_irq_restore(flags);
+ /* nothing to do if irq isn't set up */
+ if (!mn10300_serial_int_tbl[port->tx_irq].port)
+ return;
+
+ port->tx_flags |= MNSCx_TX_STOP;
+ mb();
+
+ /*
+ * Here we wait for the irq to be disabled. Either it already is
+ * disabled or we wait some number of retries for the VDMA handler
+ * to disable it. The retries give the VDMA handler enough time to
+ * run to completion if it was already in progress. If the VDMA IRQ
+ * is enabled but the handler is not yet running when arrive here,
+ * the STOP flag will prevent the handler from conflicting with the
+ * driver code following this loop.
+ */
+ while ((*port->tx_icr & GxICR_ENABLE) && retries-- > 0)
+ ;
+ if (retries <= 0) {
+ *port->tx_icr =
+ NUM2GxICR_LEVEL(CONFIG_MN10300_SERIAL_IRQ_LEVEL);
+ x = *port->tx_icr;
+ }
}
static void mn10300_serial_en_tx_intr(struct mn10300_serial_port *port)
{
- unsigned long flags;
u16 x;
- flags = arch_local_cli_save();
+ /* nothing to do if irq isn't set up */
+ if (!mn10300_serial_int_tbl[port->tx_irq].port)
+ return;
+
+ /* stop vdma irq if not already stopped */
+ if (!(port->tx_flags & MNSCx_TX_STOP))
+ mn10300_serial_dis_tx_intr(port);
+
+ port->tx_flags &= ~MNSCx_TX_STOP;
+ mb();
+
*port->tx_icr =
- NUM2GxICR_LEVEL(CONFIG_MN10300_SERIAL_IRQ_LEVEL) | GxICR_ENABLE;
+ NUM2GxICR_LEVEL(CONFIG_MN10300_SERIAL_IRQ_LEVEL) |
+ GxICR_ENABLE | GxICR_REQUEST | GxICR_DETECT;
x = *port->tx_icr;
- arch_local_irq_restore(flags);
}
static void mn10300_serial_dis_rx_intr(struct mn10300_serial_port *port)
@@ -807,8 +835,6 @@ static void mn10300_serial_start_tx(struct uart_port *_port)
struct mn10300_serial_port *port =
container_of(_port, struct mn10300_serial_port, uart);
- u16 x;
-
_enter("%s{%lu}",
port->name,
CIRC_CNT(&port->uart.state->xmit.head,
@@ -816,14 +842,7 @@ static void mn10300_serial_start_tx(struct uart_port *_port)
UART_XMIT_SIZE));
/* kick the virtual DMA controller */
- arch_local_cli();
- x = *port->tx_icr;
- x |= GxICR_ENABLE;
-
- if (*port->_status & SC01STR_TBF)
- x &= ~(GxICR_REQUEST | GxICR_DETECT);
- else
- x |= GxICR_REQUEST | GxICR_DETECT;
+ mn10300_serial_en_tx_intr(port);
_debug("CTR=%04hx ICR=%02hx STR=%04x TMD=%02hx TBR=%04hx ICR=%04hx",
*port->_control, *port->_intr, *port->_status,
@@ -831,10 +850,6 @@ static void mn10300_serial_start_tx(struct uart_port *_port)
(port->div_timer == MNSCx_DIV_TIMER_8BIT) ?
*(volatile u8 *)port->_tmxbr : *port->_tmxbr,
*port->tx_icr);
-
- *port->tx_icr = x;
- x = *port->tx_icr;
- arch_local_sti();
}
/*
@@ -844,13 +859,17 @@ static void mn10300_serial_send_xchar(struct uart_port *_port, char ch)
{
struct mn10300_serial_port *port =
container_of(_port, struct mn10300_serial_port, uart);
+ unsigned long flags;
_enter("%s,%02x", port->name, ch);
if (likely(port->gdbstub)) {
port->tx_xchar = ch;
- if (ch)
+ if (ch) {
+ spin_lock_irqsave(&port->uart.lock, flags);
mn10300_serial_en_tx_intr(port);
+ spin_unlock_irqrestore(&port->uart.lock, flags);
+ }
}
}
@@ -911,18 +930,21 @@ static void mn10300_serial_break_ctl(struct uart_port *_port, int ctl)
{
struct mn10300_serial_port *port =
container_of(_port, struct mn10300_serial_port, uart);
+ unsigned long flags;
_enter("%s,%d", port->name, ctl);
+ spin_lock_irqsave(&port->uart.lock, flags);
if (ctl) {
/* tell the virtual DMA handler to assert BREAK */
- port->tx_break = 1;
+ port->tx_flags |= MNSCx_TX_BREAK;
mn10300_serial_en_tx_intr(port);
} else {
- port->tx_break = 0;
+ port->tx_flags &= ~MNSCx_TX_BREAK;
*port->_control &= ~SC01CTR_BKE;
mn10300_serial_en_tx_intr(port);
}
+ spin_unlock_irqrestore(&port->uart.lock, flags);
}
/*
@@ -945,6 +967,7 @@ static int mn10300_serial_startup(struct uart_port *_port)
return -ENOMEM;
port->rx_inp = port->rx_outp = 0;
+ port->tx_flags = 0;
/* finally, enable the device */
*port->_intr = SC01ICR_TI;
@@ -994,14 +1017,22 @@ error:
*/
static void mn10300_serial_shutdown(struct uart_port *_port)
{
+ unsigned long flags;
u16 x;
struct mn10300_serial_port *port =
container_of(_port, struct mn10300_serial_port, uart);
_enter("%s", port->name);
+ spin_lock_irqsave(&_port->lock, flags);
+ mn10300_serial_dis_tx_intr(port);
+
+ *port->rx_icr = NUM2GxICR_LEVEL(CONFIG_MN10300_SERIAL_IRQ_LEVEL);
+ x = *port->rx_icr;
+ port->tx_flags = 0;
+ spin_unlock_irqrestore(&_port->lock, flags);
+
/* disable the serial port and its baud rate timer */
- port->tx_break = 0;
*port->_control &= ~(SC01CTR_TXE | SC01CTR_RXE | SC01CTR_BKE);
*port->_tmxmd = 0;
@@ -1016,12 +1047,8 @@ static void mn10300_serial_shutdown(struct uart_port *_port)
free_irq(port->rx_irq, port);
free_irq(port->tx_irq, port);
- arch_local_cli();
- *port->rx_icr = NUM2GxICR_LEVEL(CONFIG_MN10300_SERIAL_IRQ_LEVEL);
- x = *port->rx_icr;
- *port->tx_icr = NUM2GxICR_LEVEL(CONFIG_MN10300_SERIAL_IRQ_LEVEL);
- x = *port->tx_icr;
- arch_local_sti();
+ mn10300_serial_int_tbl[port->tx_irq].port = NULL;
+ mn10300_serial_int_tbl[port->rx_irq].port = NULL;
}
/*
@@ -1549,17 +1576,24 @@ static void mn10300_serial_console_write(struct console *co,
{
struct mn10300_serial_port *port;
unsigned i;
- u16 scxctr, txicr, tmp;
+ u16 scxctr;
u8 tmxmd;
+ unsigned long flags;
+ int locked = 1;
port = mn10300_serial_ports[co->index];
+ local_irq_save(flags);
+ if (port->uart.sysrq) {
+ /* mn10300_serial_interrupt() already took the lock */
+ locked = 0;
+ } else if (oops_in_progress) {
+ locked = spin_trylock(&port->uart.lock);
+ } else
+ spin_lock(&port->uart.lock);
+
/* firstly hijack the serial port from the "virtual DMA" controller */
- arch_local_cli();
- txicr = *port->tx_icr;
- *port->tx_icr = NUM2GxICR_LEVEL(CONFIG_MN10300_SERIAL_IRQ_LEVEL);
- tmp = *port->tx_icr;
- arch_local_sti();
+ mn10300_serial_dis_tx_intr(port);
/* the transmitter may be disabled */
scxctr = *port->_control;
@@ -1613,10 +1647,11 @@ static void mn10300_serial_console_write(struct console *co,
if (!(scxctr & SC01CTR_TXE))
*port->_control = scxctr;
- arch_local_cli();
- *port->tx_icr = txicr;
- tmp = *port->tx_icr;
- arch_local_sti();
+ mn10300_serial_en_tx_intr(port);
+
+ if (locked)
+ spin_unlock(&port->uart.lock);
+ local_irq_restore(flags);
}
/*
diff --git a/arch/mn10300/kernel/mn10300-serial.h b/arch/mn10300/kernel/mn10300-serial.h
index 6796499bf789b0136a79a066afaa44a0b901f072..0004e61619a5831740e9b413433cfe7b8eee4099 100644
--- a/arch/mn10300/kernel/mn10300-serial.h
+++ b/arch/mn10300/kernel/mn10300-serial.h
@@ -29,6 +29,10 @@
#define MNSCx_TX_SPACE 0x04
#define MNSCx_TX_EMPTY 0x08
+/* tx_flags bits */
+#define MNSCx_TX_BREAK 0x01
+#define MNSCx_TX_STOP 0x02
+
#ifndef __ASSEMBLY__
struct mn10300_serial_port {
@@ -36,7 +40,7 @@ struct mn10300_serial_port {
unsigned rx_inp; /* pointer to rx input offset */
unsigned rx_outp; /* pointer to rx output offset */
u8 tx_xchar; /* high-priority XON/XOFF buffer */
- u8 tx_break; /* transmit break request */
+ u8 tx_flags; /* transmit break/stop request */
u8 intr_flags; /* interrupt flags */
volatile u16 *rx_icr; /* Rx interrupt control register */
volatile u16 *tx_icr; /* Tx interrupt control register */