--- /dev/null
+/*
+ * drivers/serial/sb1250-duart.c
+ *
+ * Support for the asynchronous serial interface (DUART) included
+ * in the BCM1250 and derived System-On-a-Chip (SOC) devices.
+ *
+ * Copyright (c) 2007 Maciej W. Rozycki
+ *
+ * Derived from drivers/char/sb1250_duart.c for which the following
+ * copyright applies:
+ *
+ * Copyright (c) 2000, 2001, 2002, 2003, 2004 Broadcom Corporation
+ *
+ * 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.
+ *
+ * References:
+ *
+ * "BCM1250/BCM1125/BCM1125H User Manual", Broadcom Corporation
+ */
+
+#if defined(CONFIG_SERIAL_SB1250_DUART_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ)
+#define SUPPORT_SYSRQ
+#endif
+
+#include <linux/console.h>
+#include <linux/delay.h>
+#include <linux/errno.h>
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/ioport.h>
+#include <linux/kernel.h>
+#include <linux/major.h>
+#include <linux/serial.h>
+#include <linux/serial_core.h>
+#include <linux/spinlock.h>
+#include <linux/sysrq.h>
+#include <linux/tty.h>
+#include <linux/types.h>
+
+#include <asm/atomic.h>
+#include <asm/io.h>
+#include <asm/war.h>
+
+#include <asm/sibyte/sb1250.h>
+#include <asm/sibyte/sb1250_uart.h>
+#include <asm/sibyte/swarm.h>
+
+
+#if defined(CONFIG_SIBYTE_BCM1x55) || defined(CONFIG_SIBYTE_BCM1x80)
+#include <asm/sibyte/bcm1480_regs.h>
+#include <asm/sibyte/bcm1480_int.h>
+
+#define SBD_CHANREGS(line) A_BCM1480_DUART_CHANREG((line), 0)
+#define SBD_CTRLREGS(line) A_BCM1480_DUART_CTRLREG((line), 0)
+#define SBD_INT(line) (K_BCM1480_INT_UART_0 + (line))
+
+#elif defined(CONFIG_SIBYTE_SB1250) || defined(CONFIG_SIBYTE_BCM112X)
+#include <asm/sibyte/sb1250_regs.h>
+#include <asm/sibyte/sb1250_int.h>
+
+#define SBD_CHANREGS(line) A_DUART_CHANREG((line), 0)
+#define SBD_CTRLREGS(line) A_DUART_CTRLREG(0)
+#define SBD_INT(line) (K_INT_UART_0 + (line))
+
+#else
+#error invalid SB1250 UART configuration
+
+#endif
+
+
+MODULE_AUTHOR("Maciej W. Rozycki <macro@linux-mips.org>");
+MODULE_DESCRIPTION("BCM1xxx on-chip DUART serial driver");
+MODULE_LICENSE("GPL");
+
+
+#define DUART_MAX_CHIP 2
+#define DUART_MAX_SIDE 2
+
+/*
+ * Per-port state.
+ */
+struct sbd_port {
+ struct sbd_duart *duart;
+ struct uart_port port;
+ unsigned char __iomem *memctrl;
+ int tx_stopped;
+ int initialised;
+};
+
+/*
+ * Per-DUART state for the shared register space.
+ */
+struct sbd_duart {
+ struct sbd_port sport[2];
+ unsigned long mapctrl;
+ atomic_t map_guard;
+};
+
+#define to_sport(uport) container_of(uport, struct sbd_port, port)
+
+static struct sbd_duart sbd_duarts[DUART_MAX_CHIP];
+
+#define __unused __attribute__((__unused__))
+
+
+/*
+ * Reading and writing SB1250 DUART registers.
+ *
+ * There are three register spaces: two per-channel ones and
+ * a shared one. We have to define accessors appropriately.
+ * All registers are 64-bit and all but the Baud Rate Clock
+ * registers only define 8 least significant bits. There is
+ * also a workaround to take into account. Raw accessors use
+ * the full register width, but cooked ones truncate it
+ * intentionally so that the rest of the driver does not care.
+ */
+static u64 __read_sbdchn(struct sbd_port *sport, int reg)
+{
+ void __iomem *csr = sport->port.membase + reg;
+
+ return __raw_readq(csr);
+}
+
+static u64 __read_sbdshr(struct sbd_port *sport, int reg)
+{
+ void __iomem *csr = sport->memctrl + reg;
+
+ return __raw_readq(csr);
+}
+
+static void __write_sbdchn(struct sbd_port *sport, int reg, u64 value)
+{
+ void __iomem *csr = sport->port.membase + reg;
+
+ __raw_writeq(value, csr);
+}
+
+static void __write_sbdshr(struct sbd_port *sport, int reg, u64 value)
+{
+ void __iomem *csr = sport->memctrl + reg;
+
+ __raw_writeq(value, csr);
+}
+
+/*
+ * In bug 1956, we get glitches that can mess up uart registers. This
+ * "read-mode-reg after any register access" is an accepted workaround.
+ */
+static void __war_sbd1956(struct sbd_port *sport)
+{
+ __read_sbdchn(sport, R_DUART_MODE_REG_1);
+ __read_sbdchn(sport, R_DUART_MODE_REG_2);
+}
+
+static unsigned char read_sbdchn(struct sbd_port *sport, int reg)
+{
+ unsigned char retval;
+
+ retval = __read_sbdchn(sport, reg);
+ if (SIBYTE_1956_WAR)
+ __war_sbd1956(sport);
+ return retval;
+}
+
+static unsigned char read_sbdshr(struct sbd_port *sport, int reg)
+{
+ unsigned char retval;
+
+ retval = __read_sbdshr(sport, reg);
+ if (SIBYTE_1956_WAR)
+ __war_sbd1956(sport);
+ return retval;
+}
+
+static void write_sbdchn(struct sbd_port *sport, int reg, unsigned int value)
+{
+ __write_sbdchn(sport, reg, value);
+ if (SIBYTE_1956_WAR)
+ __war_sbd1956(sport);
+}
+
+static void write_sbdshr(struct sbd_port *sport, int reg, unsigned int value)
+{
+ __write_sbdshr(sport, reg, value);
+ if (SIBYTE_1956_WAR)
+ __war_sbd1956(sport);
+}
+
+
+static int sbd_receive_ready(struct sbd_port *sport)
+{
+ return read_sbdchn(sport, R_DUART_STATUS) & M_DUART_RX_RDY;
+}
+
+static int sbd_receive_drain(struct sbd_port *sport)
+{
+ int loops = 10000;
+
+ while (sbd_receive_ready(sport) && loops--)
+ read_sbdchn(sport, R_DUART_RX_HOLD);
+ return loops;
+}
+
+static int __unused sbd_transmit_ready(struct sbd_port *sport)
+{
+ return read_sbdchn(sport, R_DUART_STATUS) & M_DUART_TX_RDY;
+}
+
+static int __unused sbd_transmit_drain(struct sbd_port *sport)
+{
+ int loops = 10000;
+
+ while (!sbd_transmit_ready(sport) && loops--)
+ udelay(2);
+ return loops;
+}
+
+static int sbd_transmit_empty(struct sbd_port *sport)
+{
+ return read_sbdchn(sport, R_DUART_STATUS) & M_DUART_TX_EMT;
+}
+
+static int sbd_line_drain(struct sbd_port *sport)
+{
+ int loops = 10000;
+
+ while (!sbd_transmit_empty(sport) && loops--)
+ udelay(2);
+ return loops;
+}
+
+
+static unsigned int sbd_tx_empty(struct uart_port *uport)
+{
+ struct sbd_port *sport = to_sport(uport);
+
+ return sbd_transmit_empty(sport) ? TIOCSER_TEMT : 0;
+}
+
+static unsigned int sbd_get_mctrl(struct uart_port *uport)
+{
+ struct sbd_port *sport = to_sport(uport);
+ unsigned int mctrl, status;
+
+ status = read_sbdshr(sport, R_DUART_IN_PORT);
+ status >>= (uport->line) % 2;
+ mctrl = (!(status & M_DUART_IN_PIN0_VAL) ? TIOCM_CTS : 0) |
+ (!(status & M_DUART_IN_PIN4_VAL) ? TIOCM_CAR : 0) |
+ (!(status & M_DUART_RIN0_PIN) ? TIOCM_RNG : 0) |
+ (!(status & M_DUART_IN_PIN2_VAL) ? TIOCM_DSR : 0);
+ return mctrl;
+}
+
+static void sbd_set_mctrl(struct uart_port *uport, unsigned int mctrl)
+{
+ struct sbd_port *sport = to_sport(uport);
+ unsigned int clr = 0, set = 0, mode2;
+
+ if (mctrl & TIOCM_DTR)
+ set |= M_DUART_SET_OPR2;
+ else
+ clr |= M_DUART_CLR_OPR2;
+ if (mctrl & TIOCM_RTS)
+ set |= M_DUART_SET_OPR0;
+ else
+ clr |= M_DUART_CLR_OPR0;
+ clr <<= (uport->line) % 2;
+ set <<= (uport->line) % 2;
+
+ mode2 = read_sbdchn(sport, R_DUART_MODE_REG_2);
+ mode2 &= ~M_DUART_CHAN_MODE;
+ if (mctrl & TIOCM_LOOP)
+ mode2 |= V_DUART_CHAN_MODE_LCL_LOOP;
+ else
+ mode2 |= V_DUART_CHAN_MODE_NORMAL;
+
+ write_sbdshr(sport, R_DUART_CLEAR_OPR, clr);
+ write_sbdshr(sport, R_DUART_SET_OPR, set);
+ write_sbdchn(sport, R_DUART_MODE_REG_2, mode2);
+}
+
+static void sbd_stop_tx(struct uart_port *uport)
+{
+ struct sbd_port *sport = to_sport(uport);
+
+ write_sbdchn(sport, R_DUART_CMD, M_DUART_TX_DIS);
+ sport->tx_stopped = 1;
+};
+
+static void sbd_start_tx(struct uart_port *uport)
+{
+ struct sbd_port *sport = to_sport(uport);
+ unsigned int mask;
+
+ /* Enable tx interrupts. */
+ mask = read_sbdshr(sport, R_DUART_IMRREG((uport->line) % 2));
+ mask |= M_DUART_IMR_TX;
+ write_sbdshr(sport, R_DUART_IMRREG((uport->line) % 2), mask);
+
+ /* Go!, go!, go!... */
+ write_sbdchn(sport, R_DUART_CMD, M_DUART_TX_EN);
+ sport->tx_stopped = 0;
+};
+
+static void sbd_stop_rx(struct uart_port *uport)
+{
+ struct sbd_port *sport = to_sport(uport);
+
+ write_sbdshr(sport, R_DUART_IMRREG((uport->line) % 2), 0);
+};
+
+static void sbd_enable_ms(struct uart_port *uport)
+{
+ struct sbd_port *sport = to_sport(uport);
+
+ write_sbdchn(sport, R_DUART_AUXCTL_X,
+ M_DUART_CIN_CHNG_ENA | M_DUART_CTS_CHNG_ENA);
+}
+
+static void sbd_break_ctl(struct uart_port *uport, int break_state)
+{
+ struct sbd_port *sport = to_sport(uport);
+
+ if (break_state == -1)
+ write_sbdchn(sport, R_DUART_CMD, V_DUART_MISC_CMD_START_BREAK);
+ else
+ write_sbdchn(sport, R_DUART_CMD, V_DUART_MISC_CMD_STOP_BREAK);
+}
+
+
+static void sbd_receive_chars(struct sbd_port *sport)
+{
+ struct uart_port *uport = &sport->port;
+ struct uart_icount *icount;
+ unsigned int status, ch, flag;
+ int count;
+
+ for (count = 16; count; count--) {
+ status = read_sbdchn(sport, R_DUART_STATUS);
+ if (!(status & M_DUART_RX_RDY))
+ break;
+
+ ch = read_sbdchn(sport, R_DUART_RX_HOLD);
+
+ flag = TTY_NORMAL;
+
+ icount = &uport->icount;
+ icount->rx++;
+
+ if (unlikely(status &
+ (M_DUART_RCVD_BRK | M_DUART_FRM_ERR |
+ M_DUART_PARITY_ERR | M_DUART_OVRUN_ERR))) {
+ if (status & M_DUART_RCVD_BRK) {
+ icount->brk++;
+ if (uart_handle_break(uport))
+ continue;
+ } else if (status & M_DUART_FRM_ERR)
+ icount->frame++;
+ else if (status & M_DUART_PARITY_ERR)
+ icount->parity++;
+ if (status & M_DUART_OVRUN_ERR)
+ icount->overrun++;
+
+ status &= uport->read_status_mask;
+ if (status & M_DUART_RCVD_BRK)
+ flag = TTY_BREAK;
+ else if (status & M_DUART_FRM_ERR)
+ flag = TTY_FRAME;
+ else if (status & M_DUART_PARITY_ERR)
+ flag = TTY_PARITY;
+ }
+
+ if (uart_handle_sysrq_char(uport, ch))
+ continue;
+
+ uart_insert_char(uport, status, M_DUART_OVRUN_ERR, ch, flag);
+ }
+
+ tty_flip_buffer_push(uport->info->tty);
+}
+
+static void sbd_transmit_chars(struct sbd_port *sport)
+{
+ struct uart_port *uport = &sport->port;
+ struct circ_buf *xmit = &sport->port.info->xmit;
+ unsigned int mask;
+ int stop_tx;
+
+ /* XON/XOFF chars. */
+ if (sport->port.x_char) {
+ write_sbdchn(sport, R_DUART_TX_HOLD, sport->port.x_char);
+ sport->port.icount.tx++;
+ sport->port.x_char = 0;
+ return;
+ }
+
+ /* If nothing to do or stopped or hardware stopped. */
+ stop_tx = (uart_circ_empty(xmit) || uart_tx_stopped(&sport->port));
+
+ /* Send char. */
+ if (!stop_tx) {
+ write_sbdchn(sport, R_DUART_TX_HOLD, xmit->buf[xmit->tail]);
+ xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
+ sport->port.icount.tx++;
+
+ if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
+ uart_write_wakeup(&sport->port);
+ }
+
+ /* Are we are done? */
+ if (stop_tx || uart_circ_empty(xmit)) {
+ /* Disable tx interrupts. */
+ mask = read_sbdshr(sport, R_DUART_IMRREG((uport->line) % 2));
+ mask &= ~M_DUART_IMR_TX;
+ write_sbdshr(sport, R_DUART_IMRREG((uport->line) % 2), mask);
+ }
+}
+
+static void sbd_status_handle(struct sbd_port *sport)
+{
+ struct uart_port *uport = &sport->port;
+ unsigned int delta;
+
+ delta = read_sbdshr(sport, R_DUART_INCHREG((uport->line) % 2));
+ delta >>= (uport->line) % 2;
+
+ if (delta & (M_DUART_IN_PIN0_VAL << S_DUART_IN_PIN_CHNG))
+ uart_handle_cts_change(uport, !(delta & M_DUART_IN_PIN0_VAL));
+
+ if (delta & (M_DUART_IN_PIN2_VAL << S_DUART_IN_PIN_CHNG))
+ uport->icount.dsr++;
+
+ if (delta & ((M_DUART_IN_PIN2_VAL | M_DUART_IN_PIN0_VAL) <<
+ S_DUART_IN_PIN_CHNG))
+ wake_up_interruptible(&uport->info->delta_msr_wait);
+}
+
+static irqreturn_t sbd_interrupt(int irq, void *dev_id)
+{
+ struct sbd_port *sport = dev_id;
+ struct uart_port *uport = &sport->port;
+ irqreturn_t status = IRQ_NONE;
+ unsigned int intstat;
+ int count;
+
+ for (count = 16; count; count--) {
+ intstat = read_sbdshr(sport,
+ R_DUART_ISRREG((uport->line) % 2));
+ intstat &= read_sbdshr(sport,
+ R_DUART_IMRREG((uport->line) % 2));
+ intstat &= M_DUART_ISR_ALL;
+ if (!intstat)
+ break;
+
+ if (intstat & M_DUART_ISR_RX)
+ sbd_receive_chars(sport);
+ if (intstat & M_DUART_ISR_IN)
+ sbd_status_handle(sport);
+ if (intstat & M_DUART_ISR_TX)
+ sbd_transmit_chars(sport);
+
+ status = IRQ_HANDLED;
+ }
+
+ return status;
+}
+
+
+static int sbd_startup(struct uart_port *uport)
+{
+ struct sbd_port *sport = to_sport(uport);
+ unsigned int mode1;
+ int ret;
+
+ ret = request_irq(sport->port.irq, sbd_interrupt,
+ IRQF_SHARED, "sb1250-duart", sport);
+ if (ret)
+ return ret;
+
+ /* Clear the receive FIFO. */
+ sbd_receive_drain(sport);
+
+ /* Clear the interrupt registers. */
+ write_sbdchn(sport, R_DUART_CMD, V_DUART_MISC_CMD_RESET_BREAK_INT);
+ read_sbdshr(sport, R_DUART_INCHREG((uport->line) % 2));
+
+ /* Set rx/tx interrupt to FIFO available. */
+ mode1 = read_sbdchn(sport, R_DUART_MODE_REG_1);
+ mode1 &= ~(M_DUART_RX_IRQ_SEL_RXFULL | M_DUART_TX_IRQ_SEL_TXEMPT);
+ write_sbdchn(sport, R_DUART_MODE_REG_1, mode1);
+
+ /* Disable tx, enable rx. */
+ write_sbdchn(sport, R_DUART_CMD, M_DUART_TX_DIS | M_DUART_RX_EN);
+ sport->tx_stopped = 1;
+
+ /* Enable interrupts. */
+ write_sbdshr(sport, R_DUART_IMRREG((uport->line) % 2),
+ M_DUART_IMR_IN | M_DUART_IMR_RX);
+
+ return 0;
+}
+
+static void sbd_shutdown(struct uart_port *uport)
+{
+ struct sbd_port *sport = to_sport(uport);
+
+ write_sbdchn(sport, R_DUART_CMD, M_DUART_TX_DIS | M_DUART_RX_DIS);
+ sport->tx_stopped = 1;
+ free_irq(sport->port.irq, sport);
+}
+
+
+static void sbd_init_port(struct sbd_port *sport)
+{
+ struct uart_port *uport = &sport->port;
+
+ if (sport->initialised)
+ return;
+
+ /* There is no DUART reset feature, so just set some sane defaults. */
+ write_sbdchn(sport, R_DUART_CMD, V_DUART_MISC_CMD_RESET_TX);
+ write_sbdchn(sport, R_DUART_CMD, V_DUART_MISC_CMD_RESET_RX);
+ write_sbdchn(sport, R_DUART_MODE_REG_1, V_DUART_BITS_PER_CHAR_8);
+ write_sbdchn(sport, R_DUART_MODE_REG_2, 0);
+ write_sbdchn(sport, R_DUART_FULL_CTL,
+ V_DUART_INT_TIME(0) | V_DUART_SIG_FULL(15));
+ write_sbdchn(sport, R_DUART_OPCR_X, 0);
+ write_sbdchn(sport, R_DUART_AUXCTL_X, 0);
+ write_sbdshr(sport, R_DUART_IMRREG((uport->line) % 2), 0);
+
+ sport->initialised = 1;
+}
+
+static void sbd_set_termios(struct uart_port *uport, struct ktermios *termios,
+ struct ktermios *old_termios)
+{
+ struct sbd_port *sport = to_sport(uport);
+ unsigned int mode1 = 0, mode2 = 0, aux = 0;
+ unsigned int mode1mask = 0, mode2mask = 0, auxmask = 0;
+ unsigned int oldmode1, oldmode2, oldaux;
+ unsigned int baud, brg;
+ unsigned int command;
+
+ mode1mask |= ~(M_DUART_PARITY_MODE | M_DUART_PARITY_TYPE_ODD |
+ M_DUART_BITS_PER_CHAR);
+ mode2mask |= ~M_DUART_STOP_BIT_LEN_2;
+ auxmask |= ~M_DUART_CTS_CHNG_ENA;
+
+ /* Byte size. */
+ switch (termios->c_cflag & CSIZE) {
+ case CS5:
+ case CS6:
+ /* Unsupported, leave unchanged. */
+ mode1mask |= M_DUART_PARITY_MODE;
+ break;
+ case CS7:
+ mode1 |= V_DUART_BITS_PER_CHAR_7;
+ break;
+ case CS8:
+ default:
+ mode1 |= V_DUART_BITS_PER_CHAR_8;
+ break;
+ }
+
+ /* Parity and stop bits. */
+ if (termios->c_cflag & CSTOPB)
+ mode2 |= M_DUART_STOP_BIT_LEN_2;
+ else
+ mode2 |= M_DUART_STOP_BIT_LEN_1;
+ if (termios->c_cflag & PARENB)
+ mode1 |= V_DUART_PARITY_MODE_ADD;
+ else
+ mode1 |= V_DUART_PARITY_MODE_NONE;
+ if (termios->c_cflag & PARODD)
+ mode1 |= M_DUART_PARITY_TYPE_ODD;
+ else
+ mode1 |= M_DUART_PARITY_TYPE_EVEN;
+
+ baud = uart_get_baud_rate(uport, termios, old_termios, 1200, 5000000);
+ brg = V_DUART_BAUD_RATE(baud);
+ /* The actual lower bound is 1221bps, so compensate. */
+ if (brg > M_DUART_CLK_COUNTER)
+ brg = M_DUART_CLK_COUNTER;
+
+ uart_update_timeout(uport, termios->c_cflag, baud);
+
+ uport->read_status_mask = M_DUART_OVRUN_ERR;
+ if (termios->c_iflag & INPCK)
+ uport->read_status_mask |= M_DUART_FRM_ERR |
+ M_DUART_PARITY_ERR;
+ if (termios->c_iflag & (BRKINT | PARMRK))
+ uport->read_status_mask |= M_DUART_RCVD_BRK;
+
+ uport->ignore_status_mask = 0;
+ if (termios->c_iflag & IGNPAR)
+ uport->ignore_status_mask |= M_DUART_FRM_ERR |
+ M_DUART_PARITY_ERR;
+ if (termios->c_iflag & IGNBRK) {
+ uport->ignore_status_mask |= M_DUART_RCVD_BRK;
+ if (termios->c_iflag & IGNPAR)
+ uport->ignore_status_mask |= M_DUART_OVRUN_ERR;
+ }
+
+ if (termios->c_cflag & CREAD)
+ command = M_DUART_RX_EN;
+ else
+ command = M_DUART_RX_DIS;
+
+ if (termios->c_cflag & CRTSCTS)
+ aux |= M_DUART_CTS_CHNG_ENA;
+ else
+ aux &= ~M_DUART_CTS_CHNG_ENA;
+
+ spin_lock(&uport->lock);
+
+ if (sport->tx_stopped)
+ command |= M_DUART_TX_DIS;
+ else
+ command |= M_DUART_TX_EN;
+
+ oldmode1 = read_sbdchn(sport, R_DUART_MODE_REG_1) & mode1mask;
+ oldmode2 = read_sbdchn(sport, R_DUART_MODE_REG_2) & mode2mask;
+ oldaux = read_sbdchn(sport, R_DUART_AUXCTL_X) & auxmask;
+
+ if (!sport->tx_stopped)
+ sbd_line_drain(sport);
+ write_sbdchn(sport, R_DUART_CMD, M_DUART_TX_DIS | M_DUART_RX_DIS);
+
+ write_sbdchn(sport, R_DUART_MODE_REG_1, mode1 | oldmode1);
+ write_sbdchn(sport, R_DUART_MODE_REG_2, mode2 | oldmode2);
+ write_sbdchn(sport, R_DUART_CLK_SEL, brg);
+ write_sbdchn(sport, R_DUART_AUXCTL_X, aux | oldaux);
+
+ write_sbdchn(sport, R_DUART_CMD, command);
+
+ spin_unlock(&uport->lock);
+}
+
+
+static const char *sbd_type(struct uart_port *uport)
+{
+ return "SB1250 DUART";
+}
+
+static void sbd_release_port(struct uart_port *uport)
+{
+ struct sbd_port *sport = to_sport(uport);
+ struct sbd_duart *duart = sport->duart;
+ int map_guard;
+
+ iounmap(sport->memctrl);
+ sport->memctrl = NULL;
+ iounmap(uport->membase);
+ uport->membase = NULL;
+
+ map_guard = atomic_add_return(-1, &duart->map_guard);
+ if (!map_guard)
+ release_mem_region(duart->mapctrl, DUART_CHANREG_SPACING);
+ release_mem_region(uport->mapbase, DUART_CHANREG_SPACING);
+}
+
+static int sbd_map_port(struct uart_port *uport)
+{
+ static const char *err = KERN_ERR "sbd: Cannot map MMIO\n";
+ struct sbd_port *sport = to_sport(uport);
+ struct sbd_duart *duart = sport->duart;
+
+ if (!uport->membase)
+ uport->membase = ioremap_nocache(uport->mapbase,
+ DUART_CHANREG_SPACING);
+ if (!uport->membase) {
+ printk(err);
+ return -ENOMEM;
+ }
+
+ if (!sport->memctrl)
+ sport->memctrl = ioremap_nocache(duart->mapctrl,
+ DUART_CHANREG_SPACING);
+ if (!sport->memctrl) {
+ printk(err);
+ iounmap(uport->membase);
+ uport->membase = NULL;
+ return -ENOMEM;
+ }
+
+ return 0;
+}
+
+static int sbd_request_port(struct uart_port *uport)
+{
+ static const char *err = KERN_ERR
+ "sbd: Unable to reserve MMIO resource\n";
+ struct sbd_duart *duart = to_sport(uport)->duart;
+ int map_guard;
+ int ret = 0;
+
+ if (!request_mem_region(uport->mapbase, DUART_CHANREG_SPACING,
+ "sb1250-duart")) {
+ printk(err);
+ return -EBUSY;
+ }
+ map_guard = atomic_add_return(1, &duart->map_guard);
+ if (map_guard == 1) {
+ if (!request_mem_region(duart->mapctrl, DUART_CHANREG_SPACING,
+ "sb1250-duart")) {
+ atomic_add(-1, &duart->map_guard);
+ printk(err);
+ ret = -EBUSY;
+ }
+ }
+ if (!ret) {
+ ret = sbd_map_port(uport);
+ if (ret) {
+ map_guard = atomic_add_return(-1, &duart->map_guard);
+ if (!map_guard)
+ release_mem_region(duart->mapctrl,
+ DUART_CHANREG_SPACING);
+ }
+ }
+ if (ret) {
+ release_mem_region(uport->mapbase, DUART_CHANREG_SPACING);
+ return ret;
+ }
+ return 0;
+}
+
+static void sbd_config_port(struct uart_port *uport, int flags)
+{
+ struct sbd_port *sport = to_sport(uport);
+
+ if (flags & UART_CONFIG_TYPE) {
+ if (sbd_request_port(uport))
+ return;
+
+ uport->type = PORT_SB1250_DUART;
+
+ sbd_init_port(sport);
+ }
+}
+
+static int sbd_verify_port(struct uart_port *uport, struct serial_struct *ser)
+{
+ int ret = 0;
+
+ if (ser->type != PORT_UNKNOWN && ser->type != PORT_SB1250_DUART)
+ ret = -EINVAL;
+ if (ser->irq != uport->irq)
+ ret = -EINVAL;
+ if (ser->baud_base != uport->uartclk / 16)
+ ret = -EINVAL;
+ return ret;
+}
+
+
+static struct uart_ops sbd_ops = {
+ .tx_empty = sbd_tx_empty,
+ .set_mctrl = sbd_set_mctrl,
+ .get_mctrl = sbd_get_mctrl,
+ .stop_tx = sbd_stop_tx,
+ .start_tx = sbd_start_tx,
+ .stop_rx = sbd_stop_rx,
+ .enable_ms = sbd_enable_ms,
+ .break_ctl = sbd_break_ctl,
+ .startup = sbd_startup,
+ .shutdown = sbd_shutdown,
+ .set_termios = sbd_set_termios,
+ .type = sbd_type,
+ .release_port = sbd_release_port,
+ .request_port = sbd_request_port,
+ .config_port = sbd_config_port,
+ .verify_port = sbd_verify_port,
+};
+
+/* Initialize SB1250 DUART port structures. */
+static void __init sbd_probe_duarts(void)
+{
+ static int probed;
+ int chip, side;
+ int max_lines, line;
+
+ if (probed)
+ return;
+
+ /* Set the number of available units based on the SOC type. */
+ switch (soc_type) {
+ case K_SYS_SOC_TYPE_BCM1x55:
+ case K_SYS_SOC_TYPE_BCM1x80:
+ max_lines = 4;
+ break;
+ default:
+ /* Assume at least two serial ports at the normal address. */
+ max_lines = 2;
+ break;
+ }
+
+ probed = 1;
+
+ for (chip = 0, line = 0; chip < DUART_MAX_CHIP && line < max_lines;
+ chip++) {
+ sbd_duarts[chip].mapctrl = SBD_CTRLREGS(line);
+
+ for (side = 0; side < DUART_MAX_SIDE && line < max_lines;
+ side++, line++) {
+ struct sbd_port *sport = &sbd_duarts[chip].sport[side];
+ struct uart_port *uport = &sport->port;
+
+ sport->duart = &sbd_duarts[chip];
+
+ uport->irq = SBD_INT(line);
+ uport->uartclk = 100000000 / 20 * 16;
+ uport->fifosize = 16;
+ uport->iotype = UPIO_MEM;
+ uport->flags = UPF_BOOT_AUTOCONF;
+ uport->ops = &sbd_ops;
+ uport->line = line;
+ uport->mapbase = SBD_CHANREGS(line);
+ }
+ }
+}
+
+
+#ifdef CONFIG_SERIAL_SB1250_DUART_CONSOLE
+/*
+ * Serial console stuff. Very basic, polling driver for doing serial
+ * console output. The console_sem is held by the caller, so we
+ * shouldn't be interrupted for more console activity.
+ */
+static void sbd_console_putchar(struct uart_port *uport, int ch)
+{
+ struct sbd_port *sport = to_sport(uport);
+
+ sbd_transmit_drain(sport);
+ write_sbdchn(sport, R_DUART_TX_HOLD, ch);
+}
+
+static void sbd_console_write(struct console *co, const char *s,
+ unsigned int count)
+{
+ int chip = co->index / DUART_MAX_SIDE;
+ int side = co->index % DUART_MAX_SIDE;
+ struct sbd_port *sport = &sbd_duarts[chip].sport[side];
+ struct uart_port *uport = &sport->port;
+ unsigned long flags;
+ unsigned int mask;
+
+ /* Disable transmit interrupts and enable the transmitter. */
+ spin_lock_irqsave(&uport->lock, flags);
+ mask = read_sbdshr(sport, R_DUART_IMRREG((uport->line) % 2));
+ write_sbdshr(sport, R_DUART_IMRREG((uport->line) % 2),
+ mask & ~M_DUART_IMR_TX);
+ write_sbdchn(sport, R_DUART_CMD, M_DUART_TX_EN);
+ spin_unlock_irqrestore(&uport->lock, flags);
+
+ uart_console_write(&sport->port, s, count, sbd_console_putchar);
+
+ /* Restore transmit interrupts and the transmitter enable. */
+ spin_lock_irqsave(&uport->lock, flags);
+ sbd_line_drain(sport);
+ if (sport->tx_stopped)
+ write_sbdchn(sport, R_DUART_CMD, M_DUART_TX_DIS);
+ write_sbdshr(sport, R_DUART_IMRREG((uport->line) % 2), mask);
+ spin_unlock_irqrestore(&uport->lock, flags);
+}
+
+static int __init sbd_console_setup(struct console *co, char *options)
+{
+ int chip = co->index / DUART_MAX_SIDE;
+ int side = co->index % DUART_MAX_SIDE;
+ struct sbd_port *sport = &sbd_duarts[chip].sport[side];
+ struct uart_port *uport = &sport->port;
+ int baud = 115200;
+ int bits = 8;
+ int parity = 'n';
+ int flow = 'n';
+ int ret;
+
+ if (!sport->duart)
+ return -ENXIO;
+
+ ret = sbd_map_port(uport);
+ if (ret)
+ return ret;
+
+ sbd_init_port(sport);
+
+ if (options)
+ uart_parse_options(options, &baud, &parity, &bits, &flow);
+ return uart_set_options(uport, co, baud, parity, bits, flow);
+}
+
+static struct uart_driver sbd_reg;
+static struct console sbd_console = {
+ .name = "duart",
+ .write = sbd_console_write,
+ .device = uart_console_device,
+ .setup = sbd_console_setup,
+ .flags = CON_PRINTBUFFER,
+ .index = -1,
+ .data = &sbd_reg
+};
+
+static int __init sbd_serial_console_init(void)
+{
+ sbd_probe_duarts();
+ register_console(&sbd_console);
+
+ return 0;
+}
+
+console_initcall(sbd_serial_console_init);
+
+#define SERIAL_SB1250_DUART_CONSOLE &sbd_console
+#else
+#define SERIAL_SB1250_DUART_CONSOLE NULL
+#endif /* CONFIG_SERIAL_SB1250_DUART_CONSOLE */
+
+
+static struct uart_driver sbd_reg = {
+ .owner = THIS_MODULE,
+ .driver_name = "serial",
+ .dev_name = "duart",
+ .major = TTY_MAJOR,
+ .minor = SB1250_DUART_MINOR_BASE,
+ .nr = DUART_MAX_CHIP * DUART_MAX_SIDE,
+ .cons = SERIAL_SB1250_DUART_CONSOLE,
+};
+
+/* Set up the driver and register it. */
+static int __init sbd_init(void)
+{
+ int i, ret;
+
+ sbd_probe_duarts();
+
+ ret = uart_register_driver(&sbd_reg);
+ if (ret)
+ return ret;
+
+ for (i = 0; i < DUART_MAX_CHIP * DUART_MAX_SIDE; i++) {
+ struct sbd_duart *duart = &sbd_duarts[i / DUART_MAX_SIDE];
+ struct sbd_port *sport = &duart->sport[i % DUART_MAX_SIDE];
+ struct uart_port *uport = &sport->port;
+
+ if (sport->duart)
+ uart_add_one_port(&sbd_reg, uport);
+ }
+
+ return 0;
+}
+
+/* Unload the driver. Unregister stuff, get ready to go away. */
+static void __exit sbd_exit(void)
+{
+ int i;
+
+ for (i = DUART_MAX_CHIP * DUART_MAX_SIDE - 1; i >= 0; i--) {
+ struct sbd_duart *duart = &sbd_duarts[i / DUART_MAX_SIDE];
+ struct sbd_port *sport = &duart->sport[i % DUART_MAX_SIDE];
+ struct uart_port *uport = &sport->port;
+
+ if (sport->duart)
+ uart_remove_one_port(&sbd_reg, uport);
+ }
+
+ uart_unregister_driver(&sbd_reg);
+}
+
+module_init(sbd_init);
+module_exit(sbd_exit);
projects / GitHub / exynos8895 / android_kernel_samsung_universal8895.git / commitdiff