#ifdef CONFIG_SERIAL_8250_CONSOLE
-static void univ8250_console_write_atomic(struct console *co,
- struct nbcon_write_context *wctxt)
+static void univ8250_console_write(struct console *co, const char *s,
+ unsigned int count)
{
struct uart_8250_port *up = &serial8250_ports[co->index];
- serial8250_console_write(up, wctxt, true);
-}
-
-static void univ8250_console_write_thread(struct console *co,
- struct nbcon_write_context *wctxt)
-{
- struct uart_8250_port *up = &serial8250_ports[co->index];
-
- serial8250_console_write(up, wctxt, false);
-}
-
-static void univ8250_console_device_lock(struct console *co, unsigned long *flags)
-{
- struct uart_port *up = &serial8250_ports[co->index].port;
-
- __uart_port_lock_irqsave(up, flags);
-}
-
-static void univ8250_console_device_unlock(struct console *co, unsigned long flags)
-{
- struct uart_port *up = &serial8250_ports[co->index].port;
-
- __uart_port_unlock_irqrestore(up, flags);
+ serial8250_console_write(up, s, count);
}
static int univ8250_console_setup(struct console *co, char *options)
static struct console univ8250_console = {
.name = "ttyS",
- .write_atomic = univ8250_console_write_atomic,
- .write_thread = univ8250_console_write_thread,
- .device_lock = univ8250_console_device_lock,
- .device_unlock = univ8250_console_device_unlock,
+ .write = univ8250_console_write,
.device = uart_console_device,
.setup = univ8250_console_setup,
.exit = univ8250_console_exit,
.match = univ8250_console_match,
- .flags = CON_PRINTBUFFER | CON_ANYTIME | CON_NBCON,
+ .flags = CON_PRINTBUFFER | CON_ANYTIME,
.index = -1,
.data = &serial8250_reg,
};
serial8250_rpm_put(p);
}
-/*
- * Only to be used directly by the callback helper serial8250_console_write(),
- * which may not require the port lock. Use serial8250_clear_IER() instead for
- * all other cases.
- */
-static void __serial8250_clear_IER(struct uart_8250_port *up)
+static void serial8250_clear_IER(struct uart_8250_port *up)
{
if (up->capabilities & UART_CAP_UUE)
serial_out(up, UART_IER, UART_IER_UUE);
serial_out(up, UART_IER, 0);
}
-static inline void serial8250_clear_IER(struct uart_8250_port *up)
-{
- __serial8250_clear_IER(up);
-}
-
#ifdef CONFIG_SERIAL_8250_RSA
/*
* Attempts to turn on the RSA FIFO. Returns zero on failure.
{
unsigned char mcr = serial8250_in_MCR(p);
+ /* Port locked to synchronize UART_IER access against the console. */
+ lockdep_assert_held_once(&p->port.lock);
+
if (p->port.rs485.flags & SER_RS485_RTS_AFTER_SEND)
mcr |= UART_MCR_RTS;
else
serial8250_clear_and_reinit_fifos(p);
if (toggle_ier) {
- /*
- * Port locked to synchronize UART_IER access against
- * the console. The lockdep_assert must be restricted
- * to this condition because only here is it
- * guaranteed that the port lock is held. The other
- * hardware access in this function is synchronized
- * by console ownership.
- */
- lockdep_assert_held_once(&p->port.lock);
-
p->ier |= UART_IER_RLSI | UART_IER_RDI;
serial_port_out(&p->port, UART_IER, p->ier);
}
static void serial8250_console_putchar(struct uart_port *port, unsigned char ch)
{
- struct uart_8250_port *up = up_to_u8250p(port);
-
serial_port_out(port, UART_TX, ch);
-
- up->console_line_ended = (ch == '\n');
}
static void serial8250_console_wait_putchar(struct uart_port *port, unsigned char ch)
serial8250_out_MCR(up, up->mcr | UART_MCR_DTR | UART_MCR_RTS);
}
-static void fifo_wait_for_lsr(struct uart_8250_port *up,
- struct nbcon_write_context *wctxt,
- unsigned int count)
+static void fifo_wait_for_lsr(struct uart_8250_port *up, unsigned int count)
{
unsigned int i;
for (i = 0; i < count; i++) {
- /*
- * Pass the ownership as quickly as possible to a higher
- * priority context. Otherwise, its attempt to take over
- * the ownership might timeout. The new owner will wait
- * for UART_LSR_THRE before reusing the fifo.
- */
- if (!nbcon_can_proceed(wctxt))
- return;
-
if (wait_for_lsr(up, UART_LSR_THRE))
return;
}
* to get empty.
*/
static void serial8250_console_fifo_write(struct uart_8250_port *up,
- struct nbcon_write_context *wctxt)
+ const char *s, unsigned int count)
{
+ const char *end = s + count;
unsigned int fifosize = up->tx_loadsz;
struct uart_port *port = &up->port;
- const char *s = wctxt->outbuf;
- const char *end = s + wctxt->len;
unsigned int tx_count = 0;
bool cr_sent = false;
unsigned int i;
while (s != end) {
/* Allow timeout for each byte of a possibly full FIFO */
- fifo_wait_for_lsr(up, wctxt, fifosize);
+ fifo_wait_for_lsr(up, fifosize);
- /*
- * Fill the FIFO. If a handover or takeover occurs, writing
- * must be aborted since wctxt->outbuf and wctxt->len are no
- * longer valid.
- */
for (i = 0; i < fifosize && s != end; ++i) {
- if (!nbcon_enter_unsafe(wctxt))
- return;
-
if (*s == '\n' && !cr_sent) {
serial8250_console_putchar(port, '\r');
cr_sent = true;
serial8250_console_putchar(port, *s++);
cr_sent = false;
}
-
- nbcon_exit_unsafe(wctxt);
}
tx_count = i;
}
* Allow timeout for each byte written since the caller will only wait
* for UART_LSR_BOTH_EMPTY using the timeout of a single character
*/
- fifo_wait_for_lsr(up, wctxt, tx_count);
-}
-
-static void serial8250_console_byte_write(struct uart_8250_port *up,
- struct nbcon_write_context *wctxt)
-{
- struct uart_port *port = &up->port;
- const char *s = wctxt->outbuf;
- const char *end = s + wctxt->len;
-
- /*
- * Write out the message. If a handover or takeover occurs, writing
- * must be aborted since wctxt->outbuf and wctxt->len are no longer
- * valid.
- */
- while (s != end) {
- if (!nbcon_enter_unsafe(wctxt))
- return;
-
- uart_console_write(port, s++, 1, serial8250_console_wait_putchar);
-
- nbcon_exit_unsafe(wctxt);
- }
+ fifo_wait_for_lsr(up, tx_count);
}
/*
- * Print a string to the serial port trying not to disturb
- * any possible real use of the port...
+ * Print a string to the serial port trying not to disturb
+ * any possible real use of the port...
+ *
+ * The console_lock must be held when we get here.
*
- * Doing runtime PM is really a bad idea for the kernel console.
- * Thus, assume it is called when device is powered up.
+ * Doing runtime PM is really a bad idea for the kernel console.
+ * Thus, we assume the function is called when device is powered up.
*/
-void serial8250_console_write(struct uart_8250_port *up,
- struct nbcon_write_context *wctxt,
- bool is_atomic)
+void serial8250_console_write(struct uart_8250_port *up, const char *s,
+ unsigned int count)
{
struct uart_8250_em485 *em485 = up->em485;
struct uart_port *port = &up->port;
- unsigned int ier;
- bool use_fifo;
+ unsigned long flags;
+ unsigned int ier, use_fifo;
+ int locked = 1;
- if (!nbcon_enter_unsafe(wctxt))
- return;
+ touch_nmi_watchdog();
+
+ if (oops_in_progress)
+ locked = uart_port_trylock_irqsave(port, &flags);
+ else
+ uart_port_lock_irqsave(port, &flags);
/*
- * First, save the IER, then disable the interrupts. The special
- * variant to clear the IER is used because console printing may
- * occur without holding the port lock.
+ * First save the IER then disable the interrupts
*/
ier = serial_port_in(port, UART_IER);
- __serial8250_clear_IER(up);
+ serial8250_clear_IER(up);
/* check scratch reg to see if port powered off during system sleep */
if (up->canary && (up->canary != serial_port_in(port, UART_SCR))) {
mdelay(port->rs485.delay_rts_before_send);
}
- /* If ownership was lost, no writing is allowed */
- if (!nbcon_can_proceed(wctxt))
- goto skip_write;
-
- /*
- * If console printer did not fully output the previous line, it must
- * have been handed or taken over. Insert a newline in order to
- * maintain clean output.
- */
- if (!up->console_line_ended)
- uart_console_write(port, "\n", 1, serial8250_console_wait_putchar);
-
use_fifo = (up->capabilities & UART_CAP_FIFO) &&
/*
* BCM283x requires to check the fifo
*/
!(up->port.flags & UPF_CONS_FLOW);
- nbcon_exit_unsafe(wctxt);
-
if (likely(use_fifo))
- serial8250_console_fifo_write(up, wctxt);
+ serial8250_console_fifo_write(up, s, count);
else
- serial8250_console_byte_write(up, wctxt);
-skip_write:
- /*
- * If ownership was lost, this context must reacquire ownership and
- * re-enter the unsafe section in order to perform final actions
- * (such as re-enabling interrupts).
- */
- if (!nbcon_can_proceed(wctxt)) {
- do {
- nbcon_reacquire_nobuf(wctxt);
- } while (!nbcon_enter_unsafe(wctxt));
- }
+ uart_console_write(port, s, count, serial8250_console_wait_putchar);
/*
* Finally, wait for transmitter to become empty
* call it if we have saved something in the saved flags
* while processing with interrupts off.
*/
- if (up->msr_saved_flags) {
- /*
- * For atomic, it must be deferred to irq_work because this
- * may be a context that does not permit waking up tasks.
- */
- if (is_atomic)
- irq_work_queue(&up->modem_status_work);
- else
- serial8250_modem_status(up);
- }
+ if (up->msr_saved_flags)
+ serial8250_modem_status(up);
- nbcon_exit_unsafe(wctxt);
+ if (locked)
+ uart_port_unlock_irqrestore(port, flags);
}
static unsigned int probe_baud(struct uart_port *port)
return (port->uartclk / 16) / quot;
}
-/*
- * irq_work handler to perform modem control. Only triggered via
- * ->write_atomic() callback because it may be in a scheduler or
- * NMI context, unable to wake tasks.
- */
-static void modem_status_handler(struct irq_work *iwp)
-{
- struct uart_8250_port *up = container_of(iwp, struct uart_8250_port, modem_status_work);
- struct uart_port *port = &up->port;
-
- uart_port_lock(port);
- serial8250_modem_status(up);
- uart_port_unlock(port);
-}
-
int serial8250_console_setup(struct uart_port *port, char *options, bool probe)
{
- struct uart_8250_port *up = up_to_u8250p(port);
int baud = 9600;
int bits = 8;
int parity = 'n';
if (!port->iobase && !port->membase)
return -ENODEV;
- up->console_line_ended = true;
- init_irq_work(&up->modem_status_work, modem_status_handler);
-
if (options)
uart_parse_options(options, &baud, &parity, &bits, &flow);
else if (probe)
projects / linux.git / commitdiff