summaryrefslogtreecommitdiffstats
path: root/drivers/serial/amba-pl011.c
diff options
context:
space:
mode:
authorLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 15:20:36 -0700
committerLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 15:20:36 -0700
commit1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch)
tree0bba044c4ce775e45a88a51686b5d9f90697ea9d /drivers/serial/amba-pl011.c
downloadblackbird-op-linux-1da177e4c3f41524e886b7f1b8a0c1fc7321cac2.tar.gz
blackbird-op-linux-1da177e4c3f41524e886b7f1b8a0c1fc7321cac2.zip
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
Diffstat (limited to 'drivers/serial/amba-pl011.c')
-rw-r--r--drivers/serial/amba-pl011.c869
1 files changed, 869 insertions, 0 deletions
diff --git a/drivers/serial/amba-pl011.c b/drivers/serial/amba-pl011.c
new file mode 100644
index 000000000000..ff658a830f34
--- /dev/null
+++ b/drivers/serial/amba-pl011.c
@@ -0,0 +1,869 @@
+/*
+ * linux/drivers/char/amba.c
+ *
+ * Driver for AMBA serial ports
+ *
+ * Based on drivers/char/serial.c, by Linus Torvalds, Theodore Ts'o.
+ *
+ * Copyright 1999 ARM Limited
+ * Copyright (C) 2000 Deep Blue Solutions Ltd.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ *
+ * $Id: amba.c,v 1.41 2002/07/28 10:03:27 rmk Exp $
+ *
+ * This is a generic driver for ARM AMBA-type serial ports. They
+ * have a lot of 16550-like features, but are not register compatible.
+ * Note that although they do have CTS, DCD and DSR inputs, they do
+ * not have an RI input, nor do they have DTR or RTS outputs. If
+ * required, these have to be supplied via some other means (eg, GPIO)
+ * and hooked into this driver.
+ */
+#include <linux/config.h>
+
+#if defined(CONFIG_SERIAL_AMBA_PL011_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ)
+#define SUPPORT_SYSRQ
+#endif
+
+#include <linux/module.h>
+#include <linux/ioport.h>
+#include <linux/init.h>
+#include <linux/console.h>
+#include <linux/sysrq.h>
+#include <linux/device.h>
+#include <linux/tty.h>
+#include <linux/tty_flip.h>
+#include <linux/serial_core.h>
+#include <linux/serial.h>
+
+#include <asm/io.h>
+#include <asm/irq.h>
+#include <asm/hardware/amba.h>
+#include <asm/hardware/clock.h>
+#include <asm/hardware/amba_serial.h>
+
+#define UART_NR 14
+
+#define SERIAL_AMBA_MAJOR 204
+#define SERIAL_AMBA_MINOR 64
+#define SERIAL_AMBA_NR UART_NR
+
+#define AMBA_ISR_PASS_LIMIT 256
+
+#define UART_DUMMY_RSR_RX 256
+
+/*
+ * We wrap our port structure around the generic uart_port.
+ */
+struct uart_amba_port {
+ struct uart_port port;
+ struct clk *clk;
+ unsigned int im; /* interrupt mask */
+ unsigned int old_status;
+};
+
+static void pl011_stop_tx(struct uart_port *port, unsigned int tty_stop)
+{
+ struct uart_amba_port *uap = (struct uart_amba_port *)port;
+
+ uap->im &= ~UART011_TXIM;
+ writew(uap->im, uap->port.membase + UART011_IMSC);
+}
+
+static void pl011_start_tx(struct uart_port *port, unsigned int tty_start)
+{
+ struct uart_amba_port *uap = (struct uart_amba_port *)port;
+
+ uap->im |= UART011_TXIM;
+ writew(uap->im, uap->port.membase + UART011_IMSC);
+}
+
+static void pl011_stop_rx(struct uart_port *port)
+{
+ struct uart_amba_port *uap = (struct uart_amba_port *)port;
+
+ uap->im &= ~(UART011_RXIM|UART011_RTIM|UART011_FEIM|
+ UART011_PEIM|UART011_BEIM|UART011_OEIM);
+ writew(uap->im, uap->port.membase + UART011_IMSC);
+}
+
+static void pl011_enable_ms(struct uart_port *port)
+{
+ struct uart_amba_port *uap = (struct uart_amba_port *)port;
+
+ uap->im |= UART011_RIMIM|UART011_CTSMIM|UART011_DCDMIM|UART011_DSRMIM;
+ writew(uap->im, uap->port.membase + UART011_IMSC);
+}
+
+static void
+#ifdef SUPPORT_SYSRQ
+pl011_rx_chars(struct uart_amba_port *uap, struct pt_regs *regs)
+#else
+pl011_rx_chars(struct uart_amba_port *uap)
+#endif
+{
+ struct tty_struct *tty = uap->port.info->tty;
+ unsigned int status, ch, flag, rsr, max_count = 256;
+
+ status = readw(uap->port.membase + UART01x_FR);
+ while ((status & UART01x_FR_RXFE) == 0 && max_count--) {
+ if (tty->flip.count >= TTY_FLIPBUF_SIZE) {
+ if (tty->low_latency)
+ tty_flip_buffer_push(tty);
+ /*
+ * If this failed then we will throw away the
+ * bytes but must do so to clear interrupts
+ */
+ }
+
+ ch = readw(uap->port.membase + UART01x_DR);
+ flag = TTY_NORMAL;
+ uap->port.icount.rx++;
+
+ /*
+ * Note that the error handling code is
+ * out of the main execution path
+ */
+ rsr = readw(uap->port.membase + UART01x_RSR) | UART_DUMMY_RSR_RX;
+ if (rsr & UART01x_RSR_ANY) {
+ if (rsr & UART01x_RSR_BE) {
+ rsr &= ~(UART01x_RSR_FE | UART01x_RSR_PE);
+ uap->port.icount.brk++;
+ if (uart_handle_break(&uap->port))
+ goto ignore_char;
+ } else if (rsr & UART01x_RSR_PE)
+ uap->port.icount.parity++;
+ else if (rsr & UART01x_RSR_FE)
+ uap->port.icount.frame++;
+ if (rsr & UART01x_RSR_OE)
+ uap->port.icount.overrun++;
+
+ rsr &= uap->port.read_status_mask;
+
+ if (rsr & UART01x_RSR_BE)
+ flag = TTY_BREAK;
+ else if (rsr & UART01x_RSR_PE)
+ flag = TTY_PARITY;
+ else if (rsr & UART01x_RSR_FE)
+ flag = TTY_FRAME;
+ }
+
+ if (uart_handle_sysrq_char(&uap->port, ch, regs))
+ goto ignore_char;
+
+ if ((rsr & uap->port.ignore_status_mask) == 0) {
+ tty_insert_flip_char(tty, ch, flag);
+ }
+ if ((rsr & UART01x_RSR_OE) &&
+ tty->flip.count < TTY_FLIPBUF_SIZE) {
+ /*
+ * Overrun is special, since it's reported
+ * immediately, and doesn't affect the current
+ * character
+ */
+ tty_insert_flip_char(tty, 0, TTY_OVERRUN);
+ }
+ ignore_char:
+ status = readw(uap->port.membase + UART01x_FR);
+ }
+ tty_flip_buffer_push(tty);
+ return;
+}
+
+static void pl011_tx_chars(struct uart_amba_port *uap)
+{
+ struct circ_buf *xmit = &uap->port.info->xmit;
+ int count;
+
+ if (uap->port.x_char) {
+ writew(uap->port.x_char, uap->port.membase + UART01x_DR);
+ uap->port.icount.tx++;
+ uap->port.x_char = 0;
+ return;
+ }
+ if (uart_circ_empty(xmit) || uart_tx_stopped(&uap->port)) {
+ pl011_stop_tx(&uap->port, 0);
+ return;
+ }
+
+ count = uap->port.fifosize >> 1;
+ do {
+ writew(xmit->buf[xmit->tail], uap->port.membase + UART01x_DR);
+ xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
+ uap->port.icount.tx++;
+ if (uart_circ_empty(xmit))
+ break;
+ } while (--count > 0);
+
+ if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
+ uart_write_wakeup(&uap->port);
+
+ if (uart_circ_empty(xmit))
+ pl011_stop_tx(&uap->port, 0);
+}
+
+static void pl011_modem_status(struct uart_amba_port *uap)
+{
+ unsigned int status, delta;
+
+ status = readw(uap->port.membase + UART01x_FR) & UART01x_FR_MODEM_ANY;
+
+ delta = status ^ uap->old_status;
+ uap->old_status = status;
+
+ if (!delta)
+ return;
+
+ if (delta & UART01x_FR_DCD)
+ uart_handle_dcd_change(&uap->port, status & UART01x_FR_DCD);
+
+ if (delta & UART01x_FR_DSR)
+ uap->port.icount.dsr++;
+
+ if (delta & UART01x_FR_CTS)
+ uart_handle_cts_change(&uap->port, status & UART01x_FR_CTS);
+
+ wake_up_interruptible(&uap->port.info->delta_msr_wait);
+}
+
+static irqreturn_t pl011_int(int irq, void *dev_id, struct pt_regs *regs)
+{
+ struct uart_amba_port *uap = dev_id;
+ unsigned int status, pass_counter = AMBA_ISR_PASS_LIMIT;
+ int handled = 0;
+
+ spin_lock(&uap->port.lock);
+
+ status = readw(uap->port.membase + UART011_MIS);
+ if (status) {
+ do {
+ writew(status & ~(UART011_TXIS|UART011_RTIS|
+ UART011_RXIS),
+ uap->port.membase + UART011_ICR);
+
+ if (status & (UART011_RTIS|UART011_RXIS))
+#ifdef SUPPORT_SYSRQ
+ pl011_rx_chars(uap, regs);
+#else
+ pl011_rx_chars(uap);
+#endif
+ if (status & (UART011_DSRMIS|UART011_DCDMIS|
+ UART011_CTSMIS|UART011_RIMIS))
+ pl011_modem_status(uap);
+ if (status & UART011_TXIS)
+ pl011_tx_chars(uap);
+
+ if (pass_counter-- == 0)
+ break;
+
+ status = readw(uap->port.membase + UART011_MIS);
+ } while (status != 0);
+ handled = 1;
+ }
+
+ spin_unlock(&uap->port.lock);
+
+ return IRQ_RETVAL(handled);
+}
+
+static unsigned int pl01x_tx_empty(struct uart_port *port)
+{
+ struct uart_amba_port *uap = (struct uart_amba_port *)port;
+ unsigned int status = readw(uap->port.membase + UART01x_FR);
+ return status & (UART01x_FR_BUSY|UART01x_FR_TXFF) ? 0 : TIOCSER_TEMT;
+}
+
+static unsigned int pl01x_get_mctrl(struct uart_port *port)
+{
+ struct uart_amba_port *uap = (struct uart_amba_port *)port;
+ unsigned int result = 0;
+ unsigned int status = readw(uap->port.membase + UART01x_FR);
+
+#define BIT(uartbit, tiocmbit) \
+ if (status & uartbit) \
+ result |= tiocmbit
+
+ BIT(UART01x_FR_DCD, TIOCM_CAR);
+ BIT(UART01x_FR_DSR, TIOCM_DSR);
+ BIT(UART01x_FR_CTS, TIOCM_CTS);
+ BIT(UART011_FR_RI, TIOCM_RNG);
+#undef BIT
+ return result;
+}
+
+static void pl011_set_mctrl(struct uart_port *port, unsigned int mctrl)
+{
+ struct uart_amba_port *uap = (struct uart_amba_port *)port;
+ unsigned int cr;
+
+ cr = readw(uap->port.membase + UART011_CR);
+
+#define BIT(tiocmbit, uartbit) \
+ if (mctrl & tiocmbit) \
+ cr |= uartbit; \
+ else \
+ cr &= ~uartbit
+
+ BIT(TIOCM_RTS, UART011_CR_RTS);
+ BIT(TIOCM_DTR, UART011_CR_DTR);
+ BIT(TIOCM_OUT1, UART011_CR_OUT1);
+ BIT(TIOCM_OUT2, UART011_CR_OUT2);
+ BIT(TIOCM_LOOP, UART011_CR_LBE);
+#undef BIT
+
+ writew(cr, uap->port.membase + UART011_CR);
+}
+
+static void pl011_break_ctl(struct uart_port *port, int break_state)
+{
+ struct uart_amba_port *uap = (struct uart_amba_port *)port;
+ unsigned long flags;
+ unsigned int lcr_h;
+
+ spin_lock_irqsave(&uap->port.lock, flags);
+ lcr_h = readw(uap->port.membase + UART011_LCRH);
+ if (break_state == -1)
+ lcr_h |= UART01x_LCRH_BRK;
+ else
+ lcr_h &= ~UART01x_LCRH_BRK;
+ writew(lcr_h, uap->port.membase + UART011_LCRH);
+ spin_unlock_irqrestore(&uap->port.lock, flags);
+}
+
+static int pl011_startup(struct uart_port *port)
+{
+ struct uart_amba_port *uap = (struct uart_amba_port *)port;
+ unsigned int cr;
+ int retval;
+
+ /*
+ * Try to enable the clock producer.
+ */
+ retval = clk_enable(uap->clk);
+ if (retval)
+ goto out;
+
+ uap->port.uartclk = clk_get_rate(uap->clk);
+
+ /*
+ * Allocate the IRQ
+ */
+ retval = request_irq(uap->port.irq, pl011_int, 0, "uart-pl011", uap);
+ if (retval)
+ goto clk_dis;
+
+ writew(UART011_IFLS_RX4_8|UART011_IFLS_TX4_8,
+ uap->port.membase + UART011_IFLS);
+
+ /*
+ * Provoke TX FIFO interrupt into asserting.
+ */
+ cr = UART01x_CR_UARTEN | UART011_CR_TXE | UART011_CR_LBE;
+ writew(cr, uap->port.membase + UART011_CR);
+ writew(0, uap->port.membase + UART011_FBRD);
+ writew(1, uap->port.membase + UART011_IBRD);
+ writew(0, uap->port.membase + UART011_LCRH);
+ writew(0, uap->port.membase + UART01x_DR);
+ while (readw(uap->port.membase + UART01x_FR) & UART01x_FR_BUSY)
+ barrier();
+
+ cr = UART01x_CR_UARTEN | UART011_CR_RXE | UART011_CR_TXE;
+ writew(cr, uap->port.membase + UART011_CR);
+
+ /*
+ * initialise the old status of the modem signals
+ */
+ uap->old_status = readw(uap->port.membase + UART01x_FR) & UART01x_FR_MODEM_ANY;
+
+ /*
+ * Finally, enable interrupts
+ */
+ spin_lock_irq(&uap->port.lock);
+ uap->im = UART011_RXIM | UART011_RTIM;
+ writew(uap->im, uap->port.membase + UART011_IMSC);
+ spin_unlock_irq(&uap->port.lock);
+
+ return 0;
+
+ clk_dis:
+ clk_disable(uap->clk);
+ out:
+ return retval;
+}
+
+static void pl011_shutdown(struct uart_port *port)
+{
+ struct uart_amba_port *uap = (struct uart_amba_port *)port;
+ unsigned long val;
+
+ /*
+ * disable all interrupts
+ */
+ spin_lock_irq(&uap->port.lock);
+ uap->im = 0;
+ writew(uap->im, uap->port.membase + UART011_IMSC);
+ writew(0xffff, uap->port.membase + UART011_ICR);
+ spin_unlock_irq(&uap->port.lock);
+
+ /*
+ * Free the interrupt
+ */
+ free_irq(uap->port.irq, uap);
+
+ /*
+ * disable the port
+ */
+ writew(UART01x_CR_UARTEN | UART011_CR_TXE, uap->port.membase + UART011_CR);
+
+ /*
+ * disable break condition and fifos
+ */
+ val = readw(uap->port.membase + UART011_LCRH);
+ val &= ~(UART01x_LCRH_BRK | UART01x_LCRH_FEN);
+ writew(val, uap->port.membase + UART011_LCRH);
+
+ /*
+ * Shut down the clock producer
+ */
+ clk_disable(uap->clk);
+}
+
+static void
+pl011_set_termios(struct uart_port *port, struct termios *termios,
+ struct termios *old)
+{
+ unsigned int lcr_h, old_cr;
+ unsigned long flags;
+ unsigned int baud, quot;
+
+ /*
+ * Ask the core to calculate the divisor for us.
+ */
+ baud = uart_get_baud_rate(port, termios, old, 0, port->uartclk/16);
+ quot = port->uartclk * 4 / baud;
+
+ switch (termios->c_cflag & CSIZE) {
+ case CS5:
+ lcr_h = UART01x_LCRH_WLEN_5;
+ break;
+ case CS6:
+ lcr_h = UART01x_LCRH_WLEN_6;
+ break;
+ case CS7:
+ lcr_h = UART01x_LCRH_WLEN_7;
+ break;
+ default: // CS8
+ lcr_h = UART01x_LCRH_WLEN_8;
+ break;
+ }
+ if (termios->c_cflag & CSTOPB)
+ lcr_h |= UART01x_LCRH_STP2;
+ if (termios->c_cflag & PARENB) {
+ lcr_h |= UART01x_LCRH_PEN;
+ if (!(termios->c_cflag & PARODD))
+ lcr_h |= UART01x_LCRH_EPS;
+ }
+ if (port->fifosize > 1)
+ lcr_h |= UART01x_LCRH_FEN;
+
+ spin_lock_irqsave(&port->lock, flags);
+
+ /*
+ * Update the per-port timeout.
+ */
+ uart_update_timeout(port, termios->c_cflag, baud);
+
+ port->read_status_mask = UART01x_RSR_OE;
+ if (termios->c_iflag & INPCK)
+ port->read_status_mask |= UART01x_RSR_FE | UART01x_RSR_PE;
+ if (termios->c_iflag & (BRKINT | PARMRK))
+ port->read_status_mask |= UART01x_RSR_BE;
+
+ /*
+ * Characters to ignore
+ */
+ port->ignore_status_mask = 0;
+ if (termios->c_iflag & IGNPAR)
+ port->ignore_status_mask |= UART01x_RSR_FE | UART01x_RSR_PE;
+ if (termios->c_iflag & IGNBRK) {
+ port->ignore_status_mask |= UART01x_RSR_BE;
+ /*
+ * If we're ignoring parity and break indicators,
+ * ignore overruns too (for real raw support).
+ */
+ if (termios->c_iflag & IGNPAR)
+ port->ignore_status_mask |= UART01x_RSR_OE;
+ }
+
+ /*
+ * Ignore all characters if CREAD is not set.
+ */
+ if ((termios->c_cflag & CREAD) == 0)
+ port->ignore_status_mask |= UART_DUMMY_RSR_RX;
+
+ if (UART_ENABLE_MS(port, termios->c_cflag))
+ pl011_enable_ms(port);
+
+ /* first, disable everything */
+ old_cr = readw(port->membase + UART011_CR);
+ writew(0, port->membase + UART011_CR);
+
+ /* Set baud rate */
+ writew(quot & 0x3f, port->membase + UART011_FBRD);
+ writew(quot >> 6, port->membase + UART011_IBRD);
+
+ /*
+ * ----------v----------v----------v----------v-----
+ * NOTE: MUST BE WRITTEN AFTER UARTLCR_M & UARTLCR_L
+ * ----------^----------^----------^----------^-----
+ */
+ writew(lcr_h, port->membase + UART011_LCRH);
+ writew(old_cr, port->membase + UART011_CR);
+
+ spin_unlock_irqrestore(&port->lock, flags);
+}
+
+static const char *pl011_type(struct uart_port *port)
+{
+ return port->type == PORT_AMBA ? "AMBA/PL011" : NULL;
+}
+
+/*
+ * Release the memory region(s) being used by 'port'
+ */
+static void pl010_release_port(struct uart_port *port)
+{
+ release_mem_region(port->mapbase, SZ_4K);
+}
+
+/*
+ * Request the memory region(s) being used by 'port'
+ */
+static int pl010_request_port(struct uart_port *port)
+{
+ return request_mem_region(port->mapbase, SZ_4K, "uart-pl011")
+ != NULL ? 0 : -EBUSY;
+}
+
+/*
+ * Configure/autoconfigure the port.
+ */
+static void pl010_config_port(struct uart_port *port, int flags)
+{
+ if (flags & UART_CONFIG_TYPE) {
+ port->type = PORT_AMBA;
+ pl010_request_port(port);
+ }
+}
+
+/*
+ * verify the new serial_struct (for TIOCSSERIAL).
+ */
+static int pl010_verify_port(struct uart_port *port, struct serial_struct *ser)
+{
+ int ret = 0;
+ if (ser->type != PORT_UNKNOWN && ser->type != PORT_AMBA)
+ ret = -EINVAL;
+ if (ser->irq < 0 || ser->irq >= NR_IRQS)
+ ret = -EINVAL;
+ if (ser->baud_base < 9600)
+ ret = -EINVAL;
+ return ret;
+}
+
+static struct uart_ops amba_pl011_pops = {
+ .tx_empty = pl01x_tx_empty,
+ .set_mctrl = pl011_set_mctrl,
+ .get_mctrl = pl01x_get_mctrl,
+ .stop_tx = pl011_stop_tx,
+ .start_tx = pl011_start_tx,
+ .stop_rx = pl011_stop_rx,
+ .enable_ms = pl011_enable_ms,
+ .break_ctl = pl011_break_ctl,
+ .startup = pl011_startup,
+ .shutdown = pl011_shutdown,
+ .set_termios = pl011_set_termios,
+ .type = pl011_type,
+ .release_port = pl010_release_port,
+ .request_port = pl010_request_port,
+ .config_port = pl010_config_port,
+ .verify_port = pl010_verify_port,
+};
+
+static struct uart_amba_port *amba_ports[UART_NR];
+
+#ifdef CONFIG_SERIAL_AMBA_PL011_CONSOLE
+
+static inline void
+pl011_console_write_char(struct uart_amba_port *uap, char ch)
+{
+ unsigned int status;
+
+ do {
+ status = readw(uap->port.membase + UART01x_FR);
+ } while (status & UART01x_FR_TXFF);
+ writew(ch, uap->port.membase + UART01x_DR);
+}
+
+static void
+pl011_console_write(struct console *co, const char *s, unsigned int count)
+{
+ struct uart_amba_port *uap = amba_ports[co->index];
+ unsigned int status, old_cr, new_cr;
+ int i;
+
+ clk_enable(uap->clk);
+
+ /*
+ * First save the CR then disable the interrupts
+ */
+ old_cr = readw(uap->port.membase + UART011_CR);
+ new_cr = old_cr & ~UART011_CR_CTSEN;
+ new_cr |= UART01x_CR_UARTEN | UART011_CR_TXE;
+ writew(new_cr, uap->port.membase + UART011_CR);
+
+ /*
+ * Now, do each character
+ */
+ for (i = 0; i < count; i++) {
+ pl011_console_write_char(uap, s[i]);
+ if (s[i] == '\n')
+ pl011_console_write_char(uap, '\r');
+ }
+
+ /*
+ * Finally, wait for transmitter to become empty
+ * and restore the TCR
+ */
+ do {
+ status = readw(uap->port.membase + UART01x_FR);
+ } while (status & UART01x_FR_BUSY);
+ writew(old_cr, uap->port.membase + UART011_CR);
+
+ clk_disable(uap->clk);
+}
+
+static void __init
+pl011_console_get_options(struct uart_amba_port *uap, int *baud,
+ int *parity, int *bits)
+{
+ if (readw(uap->port.membase + UART011_CR) & UART01x_CR_UARTEN) {
+ unsigned int lcr_h, ibrd, fbrd;
+
+ lcr_h = readw(uap->port.membase + UART011_LCRH);
+
+ *parity = 'n';
+ if (lcr_h & UART01x_LCRH_PEN) {
+ if (lcr_h & UART01x_LCRH_EPS)
+ *parity = 'e';
+ else
+ *parity = 'o';
+ }
+
+ if ((lcr_h & 0x60) == UART01x_LCRH_WLEN_7)
+ *bits = 7;
+ else
+ *bits = 8;
+
+ ibrd = readw(uap->port.membase + UART011_IBRD);
+ fbrd = readw(uap->port.membase + UART011_FBRD);
+
+ *baud = uap->port.uartclk * 4 / (64 * ibrd + fbrd);
+ }
+}
+
+static int __init pl011_console_setup(struct console *co, char *options)
+{
+ struct uart_amba_port *uap;
+ int baud = 38400;
+ int bits = 8;
+ int parity = 'n';
+ int flow = 'n';
+
+ /*
+ * Check whether an invalid uart number has been specified, and
+ * if so, search for the first available port that does have
+ * console support.
+ */
+ if (co->index >= UART_NR)
+ co->index = 0;
+ uap = amba_ports[co->index];
+
+ uap->port.uartclk = clk_get_rate(uap->clk);
+
+ if (options)
+ uart_parse_options(options, &baud, &parity, &bits, &flow);
+ else
+ pl011_console_get_options(uap, &baud, &parity, &bits);
+
+ return uart_set_options(&uap->port, co, baud, parity, bits, flow);
+}
+
+extern struct uart_driver amba_reg;
+static struct console amba_console = {
+ .name = "ttyAMA",
+ .write = pl011_console_write,
+ .device = uart_console_device,
+ .setup = pl011_console_setup,
+ .flags = CON_PRINTBUFFER,
+ .index = -1,
+ .data = &amba_reg,
+};
+
+#define AMBA_CONSOLE (&amba_console)
+#else
+#define AMBA_CONSOLE NULL
+#endif
+
+static struct uart_driver amba_reg = {
+ .owner = THIS_MODULE,
+ .driver_name = "ttyAMA",
+ .dev_name = "ttyAMA",
+ .major = SERIAL_AMBA_MAJOR,
+ .minor = SERIAL_AMBA_MINOR,
+ .nr = UART_NR,
+ .cons = AMBA_CONSOLE,
+};
+
+static int pl011_probe(struct amba_device *dev, void *id)
+{
+ struct uart_amba_port *uap;
+ void __iomem *base;
+ int i, ret;
+
+ for (i = 0; i < ARRAY_SIZE(amba_ports); i++)
+ if (amba_ports[i] == NULL)
+ break;
+
+ if (i == ARRAY_SIZE(amba_ports)) {
+ ret = -EBUSY;
+ goto out;
+ }
+
+ uap = kmalloc(sizeof(struct uart_amba_port), GFP_KERNEL);
+ if (uap == NULL) {
+ ret = -ENOMEM;
+ goto out;
+ }
+
+ base = ioremap(dev->res.start, PAGE_SIZE);
+ if (!base) {
+ ret = -ENOMEM;
+ goto free;
+ }
+
+ memset(uap, 0, sizeof(struct uart_amba_port));
+ uap->clk = clk_get(&dev->dev, "UARTCLK");
+ if (IS_ERR(uap->clk)) {
+ ret = PTR_ERR(uap->clk);
+ goto unmap;
+ }
+
+ ret = clk_use(uap->clk);
+ if (ret)
+ goto putclk;
+
+ uap->port.dev = &dev->dev;
+ uap->port.mapbase = dev->res.start;
+ uap->port.membase = base;
+ uap->port.iotype = UPIO_MEM;
+ uap->port.irq = dev->irq[0];
+ uap->port.fifosize = 16;
+ uap->port.ops = &amba_pl011_pops;
+ uap->port.flags = UPF_BOOT_AUTOCONF;
+ uap->port.line = i;
+
+ amba_ports[i] = uap;
+
+ amba_set_drvdata(dev, uap);
+ ret = uart_add_one_port(&amba_reg, &uap->port);
+ if (ret) {
+ amba_set_drvdata(dev, NULL);
+ amba_ports[i] = NULL;
+ clk_unuse(uap->clk);
+ putclk:
+ clk_put(uap->clk);
+ unmap:
+ iounmap(base);
+ free:
+ kfree(uap);
+ }
+ out:
+ return ret;
+}
+
+static int pl011_remove(struct amba_device *dev)
+{
+ struct uart_amba_port *uap = amba_get_drvdata(dev);
+ int i;
+
+ amba_set_drvdata(dev, NULL);
+
+ uart_remove_one_port(&amba_reg, &uap->port);
+
+ for (i = 0; i < ARRAY_SIZE(amba_ports); i++)
+ if (amba_ports[i] == uap)
+ amba_ports[i] = NULL;
+
+ iounmap(uap->port.membase);
+ clk_unuse(uap->clk);
+ clk_put(uap->clk);
+ kfree(uap);
+ return 0;
+}
+
+static struct amba_id pl011_ids[] __initdata = {
+ {
+ .id = 0x00041011,
+ .mask = 0x000fffff,
+ },
+ { 0, 0 },
+};
+
+static struct amba_driver pl011_driver = {
+ .drv = {
+ .name = "uart-pl011",
+ },
+ .id_table = pl011_ids,
+ .probe = pl011_probe,
+ .remove = pl011_remove,
+};
+
+static int __init pl011_init(void)
+{
+ int ret;
+ printk(KERN_INFO "Serial: AMBA PL011 UART driver\n");
+
+ ret = uart_register_driver(&amba_reg);
+ if (ret == 0) {
+ ret = amba_driver_register(&pl011_driver);
+ if (ret)
+ uart_unregister_driver(&amba_reg);
+ }
+ return ret;
+}
+
+static void __exit pl011_exit(void)
+{
+ amba_driver_unregister(&pl011_driver);
+ uart_unregister_driver(&amba_reg);
+}
+
+module_init(pl011_init);
+module_exit(pl011_exit);
+
+MODULE_AUTHOR("ARM Ltd/Deep Blue Solutions Ltd");
+MODULE_DESCRIPTION("ARM AMBA serial port driver");
+MODULE_LICENSE("GPL");
OpenPOWER on IntegriCloud