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path: root/drivers/tty/serial/sh-sci.c
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-rw-r--r--drivers/tty/serial/sh-sci.c2079
1 files changed, 2079 insertions, 0 deletions
diff --git a/drivers/tty/serial/sh-sci.c b/drivers/tty/serial/sh-sci.c
new file mode 100644
index 00000000000..92c91c83edd
--- /dev/null
+++ b/drivers/tty/serial/sh-sci.c
@@ -0,0 +1,2079 @@
+/*
+ * drivers/serial/sh-sci.c
+ *
+ * SuperH on-chip serial module support. (SCI with no FIFO / with FIFO)
+ *
+ * Copyright (C) 2002 - 2011 Paul Mundt
+ * Modified to support SH7720 SCIF. Markus Brunner, Mark Jonas (Jul 2007).
+ *
+ * based off of the old drivers/char/sh-sci.c by:
+ *
+ * Copyright (C) 1999, 2000 Niibe Yutaka
+ * Copyright (C) 2000 Sugioka Toshinobu
+ * Modified to support multiple serial ports. Stuart Menefy (May 2000).
+ * Modified to support SecureEdge. David McCullough (2002)
+ * Modified to support SH7300 SCIF. Takashi Kusuda (Jun 2003).
+ * Removed SH7300 support (Jul 2007).
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License. See the file "COPYING" in the main directory of this archive
+ * for more details.
+ */
+#if defined(CONFIG_SERIAL_SH_SCI_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ)
+#define SUPPORT_SYSRQ
+#endif
+
+#undef DEBUG
+
+#include <linux/module.h>
+#include <linux/errno.h>
+#include <linux/timer.h>
+#include <linux/interrupt.h>
+#include <linux/tty.h>
+#include <linux/tty_flip.h>
+#include <linux/serial.h>
+#include <linux/major.h>
+#include <linux/string.h>
+#include <linux/sysrq.h>
+#include <linux/ioport.h>
+#include <linux/mm.h>
+#include <linux/init.h>
+#include <linux/delay.h>
+#include <linux/console.h>
+#include <linux/platform_device.h>
+#include <linux/serial_sci.h>
+#include <linux/notifier.h>
+#include <linux/cpufreq.h>
+#include <linux/clk.h>
+#include <linux/ctype.h>
+#include <linux/err.h>
+#include <linux/list.h>
+#include <linux/dmaengine.h>
+#include <linux/scatterlist.h>
+#include <linux/slab.h>
+
+#ifdef CONFIG_SUPERH
+#include <asm/sh_bios.h>
+#endif
+
+#ifdef CONFIG_H8300
+#include <asm/gpio.h>
+#endif
+
+#include "sh-sci.h"
+
+struct sci_port {
+ struct uart_port port;
+
+ /* Port type */
+ unsigned int type;
+
+ /* Port IRQs: ERI, RXI, TXI, BRI (optional) */
+ unsigned int irqs[SCIx_NR_IRQS];
+
+ /* Port enable callback */
+ void (*enable)(struct uart_port *port);
+
+ /* Port disable callback */
+ void (*disable)(struct uart_port *port);
+
+ /* Break timer */
+ struct timer_list break_timer;
+ int break_flag;
+
+ /* SCSCR initialization */
+ unsigned int scscr;
+
+ /* SCBRR calculation algo */
+ unsigned int scbrr_algo_id;
+
+ /* Interface clock */
+ struct clk *iclk;
+ /* Function clock */
+ struct clk *fclk;
+
+ struct list_head node;
+
+ struct dma_chan *chan_tx;
+ struct dma_chan *chan_rx;
+
+#ifdef CONFIG_SERIAL_SH_SCI_DMA
+ struct device *dma_dev;
+ unsigned int slave_tx;
+ unsigned int slave_rx;
+ struct dma_async_tx_descriptor *desc_tx;
+ struct dma_async_tx_descriptor *desc_rx[2];
+ dma_cookie_t cookie_tx;
+ dma_cookie_t cookie_rx[2];
+ dma_cookie_t active_rx;
+ struct scatterlist sg_tx;
+ unsigned int sg_len_tx;
+ struct scatterlist sg_rx[2];
+ size_t buf_len_rx;
+ struct sh_dmae_slave param_tx;
+ struct sh_dmae_slave param_rx;
+ struct work_struct work_tx;
+ struct work_struct work_rx;
+ struct timer_list rx_timer;
+ unsigned int rx_timeout;
+#endif
+};
+
+struct sh_sci_priv {
+ spinlock_t lock;
+ struct list_head ports;
+ struct notifier_block clk_nb;
+};
+
+/* Function prototypes */
+static void sci_stop_tx(struct uart_port *port);
+
+#define SCI_NPORTS CONFIG_SERIAL_SH_SCI_NR_UARTS
+
+static struct sci_port sci_ports[SCI_NPORTS];
+static struct uart_driver sci_uart_driver;
+
+static inline struct sci_port *
+to_sci_port(struct uart_port *uart)
+{
+ return container_of(uart, struct sci_port, port);
+}
+
+#if defined(CONFIG_CONSOLE_POLL) || defined(CONFIG_SERIAL_SH_SCI_CONSOLE)
+
+#ifdef CONFIG_CONSOLE_POLL
+static inline void handle_error(struct uart_port *port)
+{
+ /* Clear error flags */
+ sci_out(port, SCxSR, SCxSR_ERROR_CLEAR(port));
+}
+
+static int sci_poll_get_char(struct uart_port *port)
+{
+ unsigned short status;
+ int c;
+
+ do {
+ status = sci_in(port, SCxSR);
+ if (status & SCxSR_ERRORS(port)) {
+ handle_error(port);
+ continue;
+ }
+ break;
+ } while (1);
+
+ if (!(status & SCxSR_RDxF(port)))
+ return NO_POLL_CHAR;
+
+ c = sci_in(port, SCxRDR);
+
+ /* Dummy read */
+ sci_in(port, SCxSR);
+ sci_out(port, SCxSR, SCxSR_RDxF_CLEAR(port));
+
+ return c;
+}
+#endif
+
+static void sci_poll_put_char(struct uart_port *port, unsigned char c)
+{
+ unsigned short status;
+
+ do {
+ status = sci_in(port, SCxSR);
+ } while (!(status & SCxSR_TDxE(port)));
+
+ sci_out(port, SCxTDR, c);
+ sci_out(port, SCxSR, SCxSR_TDxE_CLEAR(port) & ~SCxSR_TEND(port));
+}
+#endif /* CONFIG_CONSOLE_POLL || CONFIG_SERIAL_SH_SCI_CONSOLE */
+
+#if defined(__H8300H__) || defined(__H8300S__)
+static void sci_init_pins(struct uart_port *port, unsigned int cflag)
+{
+ int ch = (port->mapbase - SMR0) >> 3;
+
+ /* set DDR regs */
+ H8300_GPIO_DDR(h8300_sci_pins[ch].port,
+ h8300_sci_pins[ch].rx,
+ H8300_GPIO_INPUT);
+ H8300_GPIO_DDR(h8300_sci_pins[ch].port,
+ h8300_sci_pins[ch].tx,
+ H8300_GPIO_OUTPUT);
+
+ /* tx mark output*/
+ H8300_SCI_DR(ch) |= h8300_sci_pins[ch].tx;
+}
+#elif defined(CONFIG_CPU_SUBTYPE_SH7710) || defined(CONFIG_CPU_SUBTYPE_SH7712)
+static inline void sci_init_pins(struct uart_port *port, unsigned int cflag)
+{
+ if (port->mapbase == 0xA4400000) {
+ __raw_writew(__raw_readw(PACR) & 0xffc0, PACR);
+ __raw_writew(__raw_readw(PBCR) & 0x0fff, PBCR);
+ } else if (port->mapbase == 0xA4410000)
+ __raw_writew(__raw_readw(PBCR) & 0xf003, PBCR);
+}
+#elif defined(CONFIG_CPU_SUBTYPE_SH7720) || defined(CONFIG_CPU_SUBTYPE_SH7721)
+static inline void sci_init_pins(struct uart_port *port, unsigned int cflag)
+{
+ unsigned short data;
+
+ if (cflag & CRTSCTS) {
+ /* enable RTS/CTS */
+ if (port->mapbase == 0xa4430000) { /* SCIF0 */
+ /* Clear PTCR bit 9-2; enable all scif pins but sck */
+ data = __raw_readw(PORT_PTCR);
+ __raw_writew((data & 0xfc03), PORT_PTCR);
+ } else if (port->mapbase == 0xa4438000) { /* SCIF1 */
+ /* Clear PVCR bit 9-2 */
+ data = __raw_readw(PORT_PVCR);
+ __raw_writew((data & 0xfc03), PORT_PVCR);
+ }
+ } else {
+ if (port->mapbase == 0xa4430000) { /* SCIF0 */
+ /* Clear PTCR bit 5-2; enable only tx and rx */
+ data = __raw_readw(PORT_PTCR);
+ __raw_writew((data & 0xffc3), PORT_PTCR);
+ } else if (port->mapbase == 0xa4438000) { /* SCIF1 */
+ /* Clear PVCR bit 5-2 */
+ data = __raw_readw(PORT_PVCR);
+ __raw_writew((data & 0xffc3), PORT_PVCR);
+ }
+ }
+}
+#elif defined(CONFIG_CPU_SH3)
+/* For SH7705, SH7706, SH7707, SH7709, SH7709A, SH7729 */
+static inline void sci_init_pins(struct uart_port *port, unsigned int cflag)
+{
+ unsigned short data;
+
+ /* We need to set SCPCR to enable RTS/CTS */
+ data = __raw_readw(SCPCR);
+ /* Clear out SCP7MD1,0, SCP6MD1,0, SCP4MD1,0*/
+ __raw_writew(data & 0x0fcf, SCPCR);
+
+ if (!(cflag & CRTSCTS)) {
+ /* We need to set SCPCR to enable RTS/CTS */
+ data = __raw_readw(SCPCR);
+ /* Clear out SCP7MD1,0, SCP4MD1,0,
+ Set SCP6MD1,0 = {01} (output) */
+ __raw_writew((data & 0x0fcf) | 0x1000, SCPCR);
+
+ data = __raw_readb(SCPDR);
+ /* Set /RTS2 (bit6) = 0 */
+ __raw_writeb(data & 0xbf, SCPDR);
+ }
+}
+#elif defined(CONFIG_CPU_SUBTYPE_SH7722)
+static inline void sci_init_pins(struct uart_port *port, unsigned int cflag)
+{
+ unsigned short data;
+
+ if (port->mapbase == 0xffe00000) {
+ data = __raw_readw(PSCR);
+ data &= ~0x03cf;
+ if (!(cflag & CRTSCTS))
+ data |= 0x0340;
+
+ __raw_writew(data, PSCR);
+ }
+}
+#elif defined(CONFIG_CPU_SUBTYPE_SH7757) || \
+ defined(CONFIG_CPU_SUBTYPE_SH7763) || \
+ defined(CONFIG_CPU_SUBTYPE_SH7780) || \
+ defined(CONFIG_CPU_SUBTYPE_SH7785) || \
+ defined(CONFIG_CPU_SUBTYPE_SH7786) || \
+ defined(CONFIG_CPU_SUBTYPE_SHX3)
+static inline void sci_init_pins(struct uart_port *port, unsigned int cflag)
+{
+ if (!(cflag & CRTSCTS))
+ __raw_writew(0x0080, SCSPTR0); /* Set RTS = 1 */
+}
+#elif defined(CONFIG_CPU_SH4) && !defined(CONFIG_CPU_SH4A)
+static inline void sci_init_pins(struct uart_port *port, unsigned int cflag)
+{
+ if (!(cflag & CRTSCTS))
+ __raw_writew(0x0080, SCSPTR2); /* Set RTS = 1 */
+}
+#else
+static inline void sci_init_pins(struct uart_port *port, unsigned int cflag)
+{
+ /* Nothing to do */
+}
+#endif
+
+#if defined(CONFIG_CPU_SUBTYPE_SH7760) || \
+ defined(CONFIG_CPU_SUBTYPE_SH7780) || \
+ defined(CONFIG_CPU_SUBTYPE_SH7785) || \
+ defined(CONFIG_CPU_SUBTYPE_SH7786)
+static int scif_txfill(struct uart_port *port)
+{
+ return sci_in(port, SCTFDR) & 0xff;
+}
+
+static int scif_txroom(struct uart_port *port)
+{
+ return SCIF_TXROOM_MAX - scif_txfill(port);
+}
+
+static int scif_rxfill(struct uart_port *port)
+{
+ return sci_in(port, SCRFDR) & 0xff;
+}
+#elif defined(CONFIG_CPU_SUBTYPE_SH7763)
+static int scif_txfill(struct uart_port *port)
+{
+ if (port->mapbase == 0xffe00000 ||
+ port->mapbase == 0xffe08000)
+ /* SCIF0/1*/
+ return sci_in(port, SCTFDR) & 0xff;
+ else
+ /* SCIF2 */
+ return sci_in(port, SCFDR) >> 8;
+}
+
+static int scif_txroom(struct uart_port *port)
+{
+ if (port->mapbase == 0xffe00000 ||
+ port->mapbase == 0xffe08000)
+ /* SCIF0/1*/
+ return SCIF_TXROOM_MAX - scif_txfill(port);
+ else
+ /* SCIF2 */
+ return SCIF2_TXROOM_MAX - scif_txfill(port);
+}
+
+static int scif_rxfill(struct uart_port *port)
+{
+ if ((port->mapbase == 0xffe00000) ||
+ (port->mapbase == 0xffe08000)) {
+ /* SCIF0/1*/
+ return sci_in(port, SCRFDR) & 0xff;
+ } else {
+ /* SCIF2 */
+ return sci_in(port, SCFDR) & SCIF2_RFDC_MASK;
+ }
+}
+#elif defined(CONFIG_ARCH_SH7372)
+static int scif_txfill(struct uart_port *port)
+{
+ if (port->type == PORT_SCIFA)
+ return sci_in(port, SCFDR) >> 8;
+ else
+ return sci_in(port, SCTFDR);
+}
+
+static int scif_txroom(struct uart_port *port)
+{
+ return port->fifosize - scif_txfill(port);
+}
+
+static int scif_rxfill(struct uart_port *port)
+{
+ if (port->type == PORT_SCIFA)
+ return sci_in(port, SCFDR) & SCIF_RFDC_MASK;
+ else
+ return sci_in(port, SCRFDR);
+}
+#else
+static int scif_txfill(struct uart_port *port)
+{
+ return sci_in(port, SCFDR) >> 8;
+}
+
+static int scif_txroom(struct uart_port *port)
+{
+ return SCIF_TXROOM_MAX - scif_txfill(port);
+}
+
+static int scif_rxfill(struct uart_port *port)
+{
+ return sci_in(port, SCFDR) & SCIF_RFDC_MASK;
+}
+#endif
+
+static int sci_txfill(struct uart_port *port)
+{
+ return !(sci_in(port, SCxSR) & SCI_TDRE);
+}
+
+static int sci_txroom(struct uart_port *port)
+{
+ return !sci_txfill(port);
+}
+
+static int sci_rxfill(struct uart_port *port)
+{
+ return (sci_in(port, SCxSR) & SCxSR_RDxF(port)) != 0;
+}
+
+/* ********************************************************************** *
+ * the interrupt related routines *
+ * ********************************************************************** */
+
+static void sci_transmit_chars(struct uart_port *port)
+{
+ struct circ_buf *xmit = &port->state->xmit;
+ unsigned int stopped = uart_tx_stopped(port);
+ unsigned short status;
+ unsigned short ctrl;
+ int count;
+
+ status = sci_in(port, SCxSR);
+ if (!(status & SCxSR_TDxE(port))) {
+ ctrl = sci_in(port, SCSCR);
+ if (uart_circ_empty(xmit))
+ ctrl &= ~SCSCR_TIE;
+ else
+ ctrl |= SCSCR_TIE;
+ sci_out(port, SCSCR, ctrl);
+ return;
+ }
+
+ if (port->type == PORT_SCI)
+ count = sci_txroom(port);
+ else
+ count = scif_txroom(port);
+
+ do {
+ unsigned char c;
+
+ if (port->x_char) {
+ c = port->x_char;
+ port->x_char = 0;
+ } else if (!uart_circ_empty(xmit) && !stopped) {
+ c = xmit->buf[xmit->tail];
+ xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
+ } else {
+ break;
+ }
+
+ sci_out(port, SCxTDR, c);
+
+ port->icount.tx++;
+ } while (--count > 0);
+
+ sci_out(port, SCxSR, SCxSR_TDxE_CLEAR(port));
+
+ if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
+ uart_write_wakeup(port);
+ if (uart_circ_empty(xmit)) {
+ sci_stop_tx(port);
+ } else {
+ ctrl = sci_in(port, SCSCR);
+
+ if (port->type != PORT_SCI) {
+ sci_in(port, SCxSR); /* Dummy read */
+ sci_out(port, SCxSR, SCxSR_TDxE_CLEAR(port));
+ }
+
+ ctrl |= SCSCR_TIE;
+ sci_out(port, SCSCR, ctrl);
+ }
+}
+
+/* On SH3, SCIF may read end-of-break as a space->mark char */
+#define STEPFN(c) ({int __c = (c); (((__c-1)|(__c)) == -1); })
+
+static inline void sci_receive_chars(struct uart_port *port)
+{
+ struct sci_port *sci_port = to_sci_port(port);
+ struct tty_struct *tty = port->state->port.tty;
+ int i, count, copied = 0;
+ unsigned short status;
+ unsigned char flag;
+
+ status = sci_in(port, SCxSR);
+ if (!(status & SCxSR_RDxF(port)))
+ return;
+
+ while (1) {
+ if (port->type == PORT_SCI)
+ count = sci_rxfill(port);
+ else
+ count = scif_rxfill(port);
+
+ /* Don't copy more bytes than there is room for in the buffer */
+ count = tty_buffer_request_room(tty, count);
+
+ /* If for any reason we can't copy more data, we're done! */
+ if (count == 0)
+ break;
+
+ if (port->type == PORT_SCI) {
+ char c = sci_in(port, SCxRDR);
+ if (uart_handle_sysrq_char(port, c) ||
+ sci_port->break_flag)
+ count = 0;
+ else
+ tty_insert_flip_char(tty, c, TTY_NORMAL);
+ } else {
+ for (i = 0; i < count; i++) {
+ char c = sci_in(port, SCxRDR);
+ status = sci_in(port, SCxSR);
+#if defined(CONFIG_CPU_SH3)
+ /* Skip "chars" during break */
+ if (sci_port->break_flag) {
+ if ((c == 0) &&
+ (status & SCxSR_FER(port))) {
+ count--; i--;
+ continue;
+ }
+
+ /* Nonzero => end-of-break */
+ dev_dbg(port->dev, "debounce<%02x>\n", c);
+ sci_port->break_flag = 0;
+
+ if (STEPFN(c)) {
+ count--; i--;
+ continue;
+ }
+ }
+#endif /* CONFIG_CPU_SH3 */
+ if (uart_handle_sysrq_char(port, c)) {
+ count--; i--;
+ continue;
+ }
+
+ /* Store data and status */
+ if (status & SCxSR_FER(port)) {
+ flag = TTY_FRAME;
+ dev_notice(port->dev, "frame error\n");
+ } else if (status & SCxSR_PER(port)) {
+ flag = TTY_PARITY;
+ dev_notice(port->dev, "parity error\n");
+ } else
+ flag = TTY_NORMAL;
+
+ tty_insert_flip_char(tty, c, flag);
+ }
+ }
+
+ sci_in(port, SCxSR); /* dummy read */
+ sci_out(port, SCxSR, SCxSR_RDxF_CLEAR(port));
+
+ copied += count;
+ port->icount.rx += count;
+ }
+
+ if (copied) {
+ /* Tell the rest of the system the news. New characters! */
+ tty_flip_buffer_push(tty);
+ } else {
+ sci_in(port, SCxSR); /* dummy read */
+ sci_out(port, SCxSR, SCxSR_RDxF_CLEAR(port));
+ }
+}
+
+#define SCI_BREAK_JIFFIES (HZ/20)
+/* The sci generates interrupts during the break,
+ * 1 per millisecond or so during the break period, for 9600 baud.
+ * So dont bother disabling interrupts.
+ * But dont want more than 1 break event.
+ * Use a kernel timer to periodically poll the rx line until
+ * the break is finished.
+ */
+static void sci_schedule_break_timer(struct sci_port *port)
+{
+ port->break_timer.expires = jiffies + SCI_BREAK_JIFFIES;
+ add_timer(&port->break_timer);
+}
+/* Ensure that two consecutive samples find the break over. */
+static void sci_break_timer(unsigned long data)
+{
+ struct sci_port *port = (struct sci_port *)data;
+
+ if (sci_rxd_in(&port->port) == 0) {
+ port->break_flag = 1;
+ sci_schedule_break_timer(port);
+ } else if (port->break_flag == 1) {
+ /* break is over. */
+ port->break_flag = 2;
+ sci_schedule_break_timer(port);
+ } else
+ port->break_flag = 0;
+}
+
+static inline int sci_handle_errors(struct uart_port *port)
+{
+ int copied = 0;
+ unsigned short status = sci_in(port, SCxSR);
+ struct tty_struct *tty = port->state->port.tty;
+
+ if (status & SCxSR_ORER(port)) {
+ /* overrun error */
+ if (tty_insert_flip_char(tty, 0, TTY_OVERRUN))
+ copied++;
+
+ dev_notice(port->dev, "overrun error");
+ }
+
+ if (status & SCxSR_FER(port)) {
+ if (sci_rxd_in(port) == 0) {
+ /* Notify of BREAK */
+ struct sci_port *sci_port = to_sci_port(port);
+
+ if (!sci_port->break_flag) {
+ sci_port->break_flag = 1;
+ sci_schedule_break_timer(sci_port);
+
+ /* Do sysrq handling. */
+ if (uart_handle_break(port))
+ return 0;
+
+ dev_dbg(port->dev, "BREAK detected\n");
+
+ if (tty_insert_flip_char(tty, 0, TTY_BREAK))
+ copied++;
+ }
+
+ } else {
+ /* frame error */
+ if (tty_insert_flip_char(tty, 0, TTY_FRAME))
+ copied++;
+
+ dev_notice(port->dev, "frame error\n");
+ }
+ }
+
+ if (status & SCxSR_PER(port)) {
+ /* parity error */
+ if (tty_insert_flip_char(tty, 0, TTY_PARITY))
+ copied++;
+
+ dev_notice(port->dev, "parity error");
+ }
+
+ if (copied)
+ tty_flip_buffer_push(tty);
+
+ return copied;
+}
+
+static inline int sci_handle_fifo_overrun(struct uart_port *port)
+{
+ struct tty_struct *tty = port->state->port.tty;
+ int copied = 0;
+
+ if (port->type != PORT_SCIF)
+ return 0;
+
+ if ((sci_in(port, SCLSR) & SCIF_ORER) != 0) {
+ sci_out(port, SCLSR, 0);
+
+ tty_insert_flip_char(tty, 0, TTY_OVERRUN);
+ tty_flip_buffer_push(tty);
+
+ dev_notice(port->dev, "overrun error\n");
+ copied++;
+ }
+
+ return copied;
+}
+
+static inline int sci_handle_breaks(struct uart_port *port)
+{
+ int copied = 0;
+ unsigned short status = sci_in(port, SCxSR);
+ struct tty_struct *tty = port->state->port.tty;
+ struct sci_port *s = to_sci_port(port);
+
+ if (uart_handle_break(port))
+ return 0;
+
+ if (!s->break_flag && status & SCxSR_BRK(port)) {
+#if defined(CONFIG_CPU_SH3)
+ /* Debounce break */
+ s->break_flag = 1;
+#endif
+ /* Notify of BREAK */
+ if (tty_insert_flip_char(tty, 0, TTY_BREAK))
+ copied++;
+
+ dev_dbg(port->dev, "BREAK detected\n");
+ }
+
+ if (copied)
+ tty_flip_buffer_push(tty);
+
+ copied += sci_handle_fifo_overrun(port);
+
+ return copied;
+}
+
+static irqreturn_t sci_rx_interrupt(int irq, void *ptr)
+{
+#ifdef CONFIG_SERIAL_SH_SCI_DMA
+ struct uart_port *port = ptr;
+ struct sci_port *s = to_sci_port(port);
+
+ if (s->chan_rx) {
+ u16 scr = sci_in(port, SCSCR);
+ u16 ssr = sci_in(port, SCxSR);
+
+ /* Disable future Rx interrupts */
+ if (port->type == PORT_SCIFA || port->type == PORT_SCIFB) {
+ disable_irq_nosync(irq);
+ scr |= 0x4000;
+ } else {
+ scr &= ~SCSCR_RIE;
+ }
+ sci_out(port, SCSCR, scr);
+ /* Clear current interrupt */
+ sci_out(port, SCxSR, ssr & ~(1 | SCxSR_RDxF(port)));
+ dev_dbg(port->dev, "Rx IRQ %lu: setup t-out in %u jiffies\n",
+ jiffies, s->rx_timeout);
+ mod_timer(&s->rx_timer, jiffies + s->rx_timeout);
+
+ return IRQ_HANDLED;
+ }
+#endif
+
+ /* I think sci_receive_chars has to be called irrespective
+ * of whether the I_IXOFF is set, otherwise, how is the interrupt
+ * to be disabled?
+ */
+ sci_receive_chars(ptr);
+
+ return IRQ_HANDLED;
+}
+
+static irqreturn_t sci_tx_interrupt(int irq, void *ptr)
+{
+ struct uart_port *port = ptr;
+ unsigned long flags;
+
+ spin_lock_irqsave(&port->lock, flags);
+ sci_transmit_chars(port);
+ spin_unlock_irqrestore(&port->lock, flags);
+
+ return IRQ_HANDLED;
+}
+
+static irqreturn_t sci_er_interrupt(int irq, void *ptr)
+{
+ struct uart_port *port = ptr;
+
+ /* Handle errors */
+ if (port->type == PORT_SCI) {
+ if (sci_handle_errors(port)) {
+ /* discard character in rx buffer */
+ sci_in(port, SCxSR);
+ sci_out(port, SCxSR, SCxSR_RDxF_CLEAR(port));
+ }
+ } else {
+ sci_handle_fifo_overrun(port);
+ sci_rx_interrupt(irq, ptr);
+ }
+
+ sci_out(port, SCxSR, SCxSR_ERROR_CLEAR(port));
+
+ /* Kick the transmission */
+ sci_tx_interrupt(irq, ptr);
+
+ return IRQ_HANDLED;
+}
+
+static irqreturn_t sci_br_interrupt(int irq, void *ptr)
+{
+ struct uart_port *port = ptr;
+
+ /* Handle BREAKs */
+ sci_handle_breaks(port);
+ sci_out(port, SCxSR, SCxSR_BREAK_CLEAR(port));
+
+ return IRQ_HANDLED;
+}
+
+static inline unsigned long port_rx_irq_mask(struct uart_port *port)
+{
+ /*
+ * Not all ports (such as SCIFA) will support REIE. Rather than
+ * special-casing the port type, we check the port initialization
+ * IRQ enable mask to see whether the IRQ is desired at all. If
+ * it's unset, it's logically inferred that there's no point in
+ * testing for it.
+ */
+ return SCSCR_RIE | (to_sci_port(port)->scscr & SCSCR_REIE);
+}
+
+static irqreturn_t sci_mpxed_interrupt(int irq, void *ptr)
+{
+ unsigned short ssr_status, scr_status, err_enabled;
+ struct uart_port *port = ptr;
+ struct sci_port *s = to_sci_port(port);
+ irqreturn_t ret = IRQ_NONE;
+
+ ssr_status = sci_in(port, SCxSR);
+ scr_status = sci_in(port, SCSCR);
+ err_enabled = scr_status & port_rx_irq_mask(port);
+
+ /* Tx Interrupt */
+ if ((ssr_status & SCxSR_TDxE(port)) && (scr_status & SCSCR_TIE) &&
+ !s->chan_tx)
+ ret = sci_tx_interrupt(irq, ptr);
+
+ /*
+ * Rx Interrupt: if we're using DMA, the DMA controller clears RDF /
+ * DR flags
+ */
+ if (((ssr_status & SCxSR_RDxF(port)) || s->chan_rx) &&
+ (scr_status & SCSCR_RIE))
+ ret = sci_rx_interrupt(irq, ptr);
+
+ /* Error Interrupt */
+ if ((ssr_status & SCxSR_ERRORS(port)) && err_enabled)
+ ret = sci_er_interrupt(irq, ptr);
+
+ /* Break Interrupt */
+ if ((ssr_status & SCxSR_BRK(port)) && err_enabled)
+ ret = sci_br_interrupt(irq, ptr);
+
+ return ret;
+}
+
+/*
+ * Here we define a transistion notifier so that we can update all of our
+ * ports' baud rate when the peripheral clock changes.
+ */
+static int sci_notifier(struct notifier_block *self,
+ unsigned long phase, void *p)
+{
+ struct sh_sci_priv *priv = container_of(self,
+ struct sh_sci_priv, clk_nb);
+ struct sci_port *sci_port;
+ unsigned long flags;
+
+ if ((phase == CPUFREQ_POSTCHANGE) ||
+ (phase == CPUFREQ_RESUMECHANGE)) {
+ spin_lock_irqsave(&priv->lock, flags);
+ list_for_each_entry(sci_port, &priv->ports, node)
+ sci_port->port.uartclk = clk_get_rate(sci_port->iclk);
+ spin_unlock_irqrestore(&priv->lock, flags);
+ }
+
+ return NOTIFY_OK;
+}
+
+static void sci_clk_enable(struct uart_port *port)
+{
+ struct sci_port *sci_port = to_sci_port(port);
+
+ clk_enable(sci_port->iclk);
+ sci_port->port.uartclk = clk_get_rate(sci_port->iclk);
+ clk_enable(sci_port->fclk);
+}
+
+static void sci_clk_disable(struct uart_port *port)
+{
+ struct sci_port *sci_port = to_sci_port(port);
+
+ clk_disable(sci_port->fclk);
+ clk_disable(sci_port->iclk);
+}
+
+static int sci_request_irq(struct sci_port *port)
+{
+ int i;
+ irqreturn_t (*handlers[4])(int irq, void *ptr) = {
+ sci_er_interrupt, sci_rx_interrupt, sci_tx_interrupt,
+ sci_br_interrupt,
+ };
+ const char *desc[] = { "SCI Receive Error", "SCI Receive Data Full",
+ "SCI Transmit Data Empty", "SCI Break" };
+
+ if (port->irqs[0] == port->irqs[1]) {
+ if (unlikely(!port->irqs[0]))
+ return -ENODEV;
+
+ if (request_irq(port->irqs[0], sci_mpxed_interrupt,
+ IRQF_DISABLED, "sci", port)) {
+ dev_err(port->port.dev, "Can't allocate IRQ\n");
+ return -ENODEV;
+ }
+ } else {
+ for (i = 0; i < ARRAY_SIZE(handlers); i++) {
+ if (unlikely(!port->irqs[i]))
+ continue;
+
+ if (request_irq(port->irqs[i], handlers[i],
+ IRQF_DISABLED, desc[i], port)) {
+ dev_err(port->port.dev, "Can't allocate IRQ\n");
+ return -ENODEV;
+ }
+ }
+ }
+
+ return 0;
+}
+
+static void sci_free_irq(struct sci_port *port)
+{
+ int i;
+
+ if (port->irqs[0] == port->irqs[1])
+ free_irq(port->irqs[0], port);
+ else {
+ for (i = 0; i < ARRAY_SIZE(port->irqs); i++) {
+ if (!port->irqs[i])
+ continue;
+
+ free_irq(port->irqs[i], port);
+ }
+ }
+}
+
+static unsigned int sci_tx_empty(struct uart_port *port)
+{
+ unsigned short status = sci_in(port, SCxSR);
+ unsigned short in_tx_fifo = scif_txfill(port);
+
+ return (status & SCxSR_TEND(port)) && !in_tx_fifo ? TIOCSER_TEMT : 0;
+}
+
+static void sci_set_mctrl(struct uart_port *port, unsigned int mctrl)
+{
+ /* This routine is used for seting signals of: DTR, DCD, CTS/RTS */
+ /* We use SCIF's hardware for CTS/RTS, so don't need any for that. */
+ /* If you have signals for DTR and DCD, please implement here. */
+}
+
+static unsigned int sci_get_mctrl(struct uart_port *port)
+{
+ /* This routine is used for getting signals of: DTR, DCD, DSR, RI,
+ and CTS/RTS */
+
+ return TIOCM_DTR | TIOCM_RTS | TIOCM_DSR;
+}
+
+#ifdef CONFIG_SERIAL_SH_SCI_DMA
+static void sci_dma_tx_complete(void *arg)
+{
+ struct sci_port *s = arg;
+ struct uart_port *port = &s->port;
+ struct circ_buf *xmit = &port->state->xmit;
+ unsigned long flags;
+
+ dev_dbg(port->dev, "%s(%d)\n", __func__, port->line);
+
+ spin_lock_irqsave(&port->lock, flags);
+
+ xmit->tail += sg_dma_len(&s->sg_tx);
+ xmit->tail &= UART_XMIT_SIZE - 1;
+
+ port->icount.tx += sg_dma_len(&s->sg_tx);
+
+ async_tx_ack(s->desc_tx);
+ s->cookie_tx = -EINVAL;
+ s->desc_tx = NULL;
+
+ if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
+ uart_write_wakeup(port);
+
+ if (!uart_circ_empty(xmit)) {
+ schedule_work(&s->work_tx);
+ } else if (port->type == PORT_SCIFA || port->type == PORT_SCIFB) {
+ u16 ctrl = sci_in(port, SCSCR);
+ sci_out(port, SCSCR, ctrl & ~SCSCR_TIE);
+ }
+
+ spin_unlock_irqrestore(&port->lock, flags);
+}
+
+/* Locking: called with port lock held */
+static int sci_dma_rx_push(struct sci_port *s, struct tty_struct *tty,
+ size_t count)
+{
+ struct uart_port *port = &s->port;
+ int i, active, room;
+
+ room = tty_buffer_request_room(tty, count);
+
+ if (s->active_rx == s->cookie_rx[0]) {
+ active = 0;
+ } else if (s->active_rx == s->cookie_rx[1]) {
+ active = 1;
+ } else {
+ dev_err(port->dev, "cookie %d not found!\n", s->active_rx);
+ return 0;
+ }
+
+ if (room < count)
+ dev_warn(port->dev, "Rx overrun: dropping %u bytes\n",
+ count - room);
+ if (!room)
+ return room;
+
+ for (i = 0; i < room; i++)
+ tty_insert_flip_char(tty, ((u8 *)sg_virt(&s->sg_rx[active]))[i],
+ TTY_NORMAL);
+
+ port->icount.rx += room;
+
+ return room;
+}
+
+static void sci_dma_rx_complete(void *arg)
+{
+ struct sci_port *s = arg;
+ struct uart_port *port = &s->port;
+ struct tty_struct *tty = port->state->port.tty;
+ unsigned long flags;
+ int count;
+
+ dev_dbg(port->dev, "%s(%d) active #%d\n", __func__, port->line, s->active_rx);
+
+ spin_lock_irqsave(&port->lock, flags);
+
+ count = sci_dma_rx_push(s, tty, s->buf_len_rx);
+
+ mod_timer(&s->rx_timer, jiffies + s->rx_timeout);
+
+ spin_unlock_irqrestore(&port->lock, flags);
+
+ if (count)
+ tty_flip_buffer_push(tty);
+
+ schedule_work(&s->work_rx);
+}
+
+static void sci_start_rx(struct uart_port *port);
+static void sci_start_tx(struct uart_port *port);
+
+static void sci_rx_dma_release(struct sci_port *s, bool enable_pio)
+{
+ struct dma_chan *chan = s->chan_rx;
+ struct uart_port *port = &s->port;
+
+ s->chan_rx = NULL;
+ s->cookie_rx[0] = s->cookie_rx[1] = -EINVAL;
+ dma_release_channel(chan);
+ if (sg_dma_address(&s->sg_rx[0]))
+ dma_free_coherent(port->dev, s->buf_len_rx * 2,
+ sg_virt(&s->sg_rx[0]), sg_dma_address(&s->sg_rx[0]));
+ if (enable_pio)
+ sci_start_rx(port);
+}
+
+static void sci_tx_dma_release(struct sci_port *s, bool enable_pio)
+{
+ struct dma_chan *chan = s->chan_tx;
+ struct uart_port *port = &s->port;
+
+ s->chan_tx = NULL;
+ s->cookie_tx = -EINVAL;
+ dma_release_channel(chan);
+ if (enable_pio)
+ sci_start_tx(port);
+}
+
+static void sci_submit_rx(struct sci_port *s)
+{
+ struct dma_chan *chan = s->chan_rx;
+ int i;
+
+ for (i = 0; i < 2; i++) {
+ struct scatterlist *sg = &s->sg_rx[i];
+ struct dma_async_tx_descriptor *desc;
+
+ desc = chan->device->device_prep_slave_sg(chan,
+ sg, 1, DMA_FROM_DEVICE, DMA_PREP_INTERRUPT);
+
+ if (desc) {
+ s->desc_rx[i] = desc;
+ desc->callback = sci_dma_rx_complete;
+ desc->callback_param = s;
+ s->cookie_rx[i] = desc->tx_submit(desc);
+ }
+
+ if (!desc || s->cookie_rx[i] < 0) {
+ if (i) {
+ async_tx_ack(s->desc_rx[0]);
+ s->cookie_rx[0] = -EINVAL;
+ }
+ if (desc) {
+ async_tx_ack(desc);
+ s->cookie_rx[i] = -EINVAL;
+ }
+ dev_warn(s->port.dev,
+ "failed to re-start DMA, using PIO\n");
+ sci_rx_dma_release(s, true);
+ return;
+ }
+ dev_dbg(s->port.dev, "%s(): cookie %d to #%d\n", __func__,
+ s->cookie_rx[i], i);
+ }
+
+ s->active_rx = s->cookie_rx[0];
+
+ dma_async_issue_pending(chan);
+}
+
+static void work_fn_rx(struct work_struct *work)
+{
+ struct sci_port *s = container_of(work, struct sci_port, work_rx);
+ struct uart_port *port = &s->port;
+ struct dma_async_tx_descriptor *desc;
+ int new;
+
+ if (s->active_rx == s->cookie_rx[0]) {
+ new = 0;
+ } else if (s->active_rx == s->cookie_rx[1]) {
+ new = 1;
+ } else {
+ dev_err(port->dev, "cookie %d not found!\n", s->active_rx);
+ return;
+ }
+ desc = s->desc_rx[new];
+
+ if (dma_async_is_tx_complete(s->chan_rx, s->active_rx, NULL, NULL) !=
+ DMA_SUCCESS) {
+ /* Handle incomplete DMA receive */
+ struct tty_struct *tty = port->state->port.tty;
+ struct dma_chan *chan = s->chan_rx;
+ struct sh_desc *sh_desc = container_of(desc, struct sh_desc,
+ async_tx);
+ unsigned long flags;
+ int count;
+
+ chan->device->device_control(chan, DMA_TERMINATE_ALL, 0);
+ dev_dbg(port->dev, "Read %u bytes with cookie %d\n",
+ sh_desc->partial, sh_desc->cookie);
+
+ spin_lock_irqsave(&port->lock, flags);
+ count = sci_dma_rx_push(s, tty, sh_desc->partial);
+ spin_unlock_irqrestore(&port->lock, flags);
+
+ if (count)
+ tty_flip_buffer_push(tty);
+
+ sci_submit_rx(s);
+
+ return;
+ }
+
+ s->cookie_rx[new] = desc->tx_submit(desc);
+ if (s->cookie_rx[new] < 0) {
+ dev_warn(port->dev, "Failed submitting Rx DMA descriptor\n");
+ sci_rx_dma_release(s, true);
+ return;
+ }
+
+ s->active_rx = s->cookie_rx[!new];
+
+ dev_dbg(port->dev, "%s: cookie %d #%d, new active #%d\n", __func__,
+ s->cookie_rx[new], new, s->active_rx);
+}
+
+static void work_fn_tx(struct work_struct *work)
+{
+ struct sci_port *s = container_of(work, struct sci_port, work_tx);
+ struct dma_async_tx_descriptor *desc;
+ struct dma_chan *chan = s->chan_tx;
+ struct uart_port *port = &s->port;
+ struct circ_buf *xmit = &port->state->xmit;
+ struct scatterlist *sg = &s->sg_tx;
+
+ /*
+ * DMA is idle now.
+ * Port xmit buffer is already mapped, and it is one page... Just adjust
+ * offsets and lengths. Since it is a circular buffer, we have to
+ * transmit till the end, and then the rest. Take the port lock to get a
+ * consistent xmit buffer state.
+ */
+ spin_lock_irq(&port->lock);
+ sg->offset = xmit->tail & (UART_XMIT_SIZE - 1);
+ sg_dma_address(sg) = (sg_dma_address(sg) & ~(UART_XMIT_SIZE - 1)) +
+ sg->offset;
+ sg_dma_len(sg) = min((int)CIRC_CNT(xmit->head, xmit->tail, UART_XMIT_SIZE),
+ CIRC_CNT_TO_END(xmit->head, xmit->tail, UART_XMIT_SIZE));
+ spin_unlock_irq(&port->lock);
+
+ BUG_ON(!sg_dma_len(sg));
+
+ desc = chan->device->device_prep_slave_sg(chan,
+ sg, s->sg_len_tx, DMA_TO_DEVICE,
+ DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
+ if (!desc) {
+ /* switch to PIO */
+ sci_tx_dma_release(s, true);
+ return;
+ }
+
+ dma_sync_sg_for_device(port->dev, sg, 1, DMA_TO_DEVICE);
+
+ spin_lock_irq(&port->lock);
+ s->desc_tx = desc;
+ desc->callback = sci_dma_tx_complete;
+ desc->callback_param = s;
+ spin_unlock_irq(&port->lock);
+ s->cookie_tx = desc->tx_submit(desc);
+ if (s->cookie_tx < 0) {
+ dev_warn(port->dev, "Failed submitting Tx DMA descriptor\n");
+ /* switch to PIO */
+ sci_tx_dma_release(s, true);
+ return;
+ }
+
+ dev_dbg(port->dev, "%s: %p: %d...%d, cookie %d\n", __func__,
+ xmit->buf, xmit->tail, xmit->head, s->cookie_tx);
+
+ dma_async_issue_pending(chan);
+}
+#endif
+
+static void sci_start_tx(struct uart_port *port)
+{
+ struct sci_port *s = to_sci_port(port);
+ unsigned short ctrl;
+
+#ifdef CONFIG_SERIAL_SH_SCI_DMA
+ if (port->type == PORT_SCIFA || port->type == PORT_SCIFB) {
+ u16 new, scr = sci_in(port, SCSCR);
+ if (s->chan_tx)
+ new = scr | 0x8000;
+ else
+ new = scr & ~0x8000;
+ if (new != scr)
+ sci_out(port, SCSCR, new);
+ }
+
+ if (s->chan_tx && !uart_circ_empty(&s->port.state->xmit) &&
+ s->cookie_tx < 0)
+ schedule_work(&s->work_tx);
+#endif
+
+ if (!s->chan_tx || port->type == PORT_SCIFA || port->type == PORT_SCIFB) {
+ /* Set TIE (Transmit Interrupt Enable) bit in SCSCR */
+ ctrl = sci_in(port, SCSCR);
+ sci_out(port, SCSCR, ctrl | SCSCR_TIE);
+ }
+}
+
+static void sci_stop_tx(struct uart_port *port)
+{
+ unsigned short ctrl;
+
+ /* Clear TIE (Transmit Interrupt Enable) bit in SCSCR */
+ ctrl = sci_in(port, SCSCR);
+
+ if (port->type == PORT_SCIFA || port->type == PORT_SCIFB)
+ ctrl &= ~0x8000;
+
+ ctrl &= ~SCSCR_TIE;
+
+ sci_out(port, SCSCR, ctrl);
+}
+
+static void sci_start_rx(struct uart_port *port)
+{
+ unsigned short ctrl;
+
+ ctrl = sci_in(port, SCSCR) | port_rx_irq_mask(port);
+
+ if (port->type == PORT_SCIFA || port->type == PORT_SCIFB)
+ ctrl &= ~0x4000;
+
+ sci_out(port, SCSCR, ctrl);
+}
+
+static void sci_stop_rx(struct uart_port *port)
+{
+ unsigned short ctrl;
+
+ ctrl = sci_in(port, SCSCR);
+
+ if (port->type == PORT_SCIFA || port->type == PORT_SCIFB)
+ ctrl &= ~0x4000;
+
+ ctrl &= ~port_rx_irq_mask(port);
+
+ sci_out(port, SCSCR, ctrl);
+}
+
+static void sci_enable_ms(struct uart_port *port)
+{
+ /* Nothing here yet .. */
+}
+
+static void sci_break_ctl(struct uart_port *port, int break_state)
+{
+ /* Nothing here yet .. */
+}
+
+#ifdef CONFIG_SERIAL_SH_SCI_DMA
+static bool filter(struct dma_chan *chan, void *slave)
+{
+ struct sh_dmae_slave *param = slave;
+
+ dev_dbg(chan->device->dev, "%s: slave ID %d\n", __func__,
+ param->slave_id);
+
+ if (param->dma_dev == chan->device->dev) {
+ chan->private = param;
+ return true;
+ } else {
+ return false;
+ }
+}
+
+static void rx_timer_fn(unsigned long arg)
+{
+ struct sci_port *s = (struct sci_port *)arg;
+ struct uart_port *port = &s->port;
+ u16 scr = sci_in(port, SCSCR);
+
+ if (port->type == PORT_SCIFA || port->type == PORT_SCIFB) {
+ scr &= ~0x4000;
+ enable_irq(s->irqs[1]);
+ }
+ sci_out(port, SCSCR, scr | SCSCR_RIE);
+ dev_dbg(port->dev, "DMA Rx timed out\n");
+ schedule_work(&s->work_rx);
+}
+
+static void sci_request_dma(struct uart_port *port)
+{
+ struct sci_port *s = to_sci_port(port);
+ struct sh_dmae_slave *param;
+ struct dma_chan *chan;
+ dma_cap_mask_t mask;
+ int nent;
+
+ dev_dbg(port->dev, "%s: port %d DMA %p\n", __func__,
+ port->line, s->dma_dev);
+
+ if (!s->dma_dev)
+ return;
+
+ dma_cap_zero(mask);
+ dma_cap_set(DMA_SLAVE, mask);
+
+ param = &s->param_tx;
+
+ /* Slave ID, e.g., SHDMA_SLAVE_SCIF0_TX */
+ param->slave_id = s->slave_tx;
+ param->dma_dev = s->dma_dev;
+
+ s->cookie_tx = -EINVAL;
+ chan = dma_request_channel(mask, filter, param);
+ dev_dbg(port->dev, "%s: TX: got channel %p\n", __func__, chan);
+ if (chan) {
+ s->chan_tx = chan;
+ sg_init_table(&s->sg_tx, 1);
+ /* UART circular tx buffer is an aligned page. */
+ BUG_ON((int)port->state->xmit.buf & ~PAGE_MASK);
+ sg_set_page(&s->sg_tx, virt_to_page(port->state->xmit.buf),
+ UART_XMIT_SIZE, (int)port->state->xmit.buf & ~PAGE_MASK);
+ nent = dma_map_sg(port->dev, &s->sg_tx, 1, DMA_TO_DEVICE);
+ if (!nent)
+ sci_tx_dma_release(s, false);
+ else
+ dev_dbg(port->dev, "%s: mapped %d@%p to %x\n", __func__,
+ sg_dma_len(&s->sg_tx),
+ port->state->xmit.buf, sg_dma_address(&s->sg_tx));
+
+ s->sg_len_tx = nent;
+
+ INIT_WORK(&s->work_tx, work_fn_tx);
+ }
+
+ param = &s->param_rx;
+
+ /* Slave ID, e.g., SHDMA_SLAVE_SCIF0_RX */
+ param->slave_id = s->slave_rx;
+ param->dma_dev = s->dma_dev;
+
+ chan = dma_request_channel(mask, filter, param);
+ dev_dbg(port->dev, "%s: RX: got channel %p\n", __func__, chan);
+ if (chan) {
+ dma_addr_t dma[2];
+ void *buf[2];
+ int i;
+
+ s->chan_rx = chan;
+
+ s->buf_len_rx = 2 * max(16, (int)port->fifosize);
+ buf[0] = dma_alloc_coherent(port->dev, s->buf_len_rx * 2,
+ &dma[0], GFP_KERNEL);
+
+ if (!buf[0]) {
+ dev_warn(port->dev,
+ "failed to allocate dma buffer, using PIO\n");
+ sci_rx_dma_release(s, true);
+ return;
+ }
+
+ buf[1] = buf[0] + s->buf_len_rx;
+ dma[1] = dma[0] + s->buf_len_rx;
+
+ for (i = 0; i < 2; i++) {
+ struct scatterlist *sg = &s->sg_rx[i];
+
+ sg_init_table(sg, 1);
+ sg_set_page(sg, virt_to_page(buf[i]), s->buf_len_rx,
+ (int)buf[i] & ~PAGE_MASK);
+ sg_dma_address(sg) = dma[i];
+ }
+
+ INIT_WORK(&s->work_rx, work_fn_rx);
+ setup_timer(&s->rx_timer, rx_timer_fn, (unsigned long)s);
+
+ sci_submit_rx(s);
+ }
+}
+
+static void sci_free_dma(struct uart_port *port)
+{
+ struct sci_port *s = to_sci_port(port);
+
+ if (!s->dma_dev)
+ return;
+
+ if (s->chan_tx)
+ sci_tx_dma_release(s, false);
+ if (s->chan_rx)
+ sci_rx_dma_release(s, false);
+}
+#endif
+
+static int sci_startup(struct uart_port *port)
+{
+ struct sci_port *s = to_sci_port(port);
+
+ dev_dbg(port->dev, "%s(%d)\n", __func__, port->line);
+
+ if (s->enable)
+ s->enable(port);
+
+ sci_request_irq(s);
+#ifdef CONFIG_SERIAL_SH_SCI_DMA
+ sci_request_dma(port);
+#endif
+ sci_start_tx(port);
+ sci_start_rx(port);
+
+ return 0;
+}
+
+static void sci_shutdown(struct uart_port *port)
+{
+ struct sci_port *s = to_sci_port(port);
+
+ dev_dbg(port->dev, "%s(%d)\n", __func__, port->line);
+
+ sci_stop_rx(port);
+ sci_stop_tx(port);
+#ifdef CONFIG_SERIAL_SH_SCI_DMA
+ sci_free_dma(port);
+#endif
+ sci_free_irq(s);
+
+ if (s->disable)
+ s->disable(port);
+}
+
+static unsigned int sci_scbrr_calc(unsigned int algo_id, unsigned int bps,
+ unsigned long freq)
+{
+ switch (algo_id) {
+ case SCBRR_ALGO_1:
+ return ((freq + 16 * bps) / (16 * bps) - 1);
+ case SCBRR_ALGO_2:
+ return ((freq + 16 * bps) / (32 * bps) - 1);
+ case SCBRR_ALGO_3:
+ return (((freq * 2) + 16 * bps) / (16 * bps) - 1);
+ case SCBRR_ALGO_4:
+ return (((freq * 2) + 16 * bps) / (32 * bps) - 1);
+ case SCBRR_ALGO_5:
+ return (((freq * 1000 / 32) / bps) - 1);
+ }
+
+ /* Warn, but use a safe default */
+ WARN_ON(1);
+ return ((freq + 16 * bps) / (32 * bps) - 1);
+}
+
+static void sci_set_termios(struct uart_port *port, struct ktermios *termios,
+ struct ktermios *old)
+{
+ struct sci_port *s = to_sci_port(port);
+ unsigned int status, baud, smr_val, max_baud;
+ int t = -1;
+ u16 scfcr = 0;
+
+ /*
+ * earlyprintk comes here early on with port->uartclk set to zero.
+ * the clock framework is not up and running at this point so here
+ * we assume that 115200 is the maximum baud rate. please note that
+ * the baud rate is not programmed during earlyprintk - it is assumed
+ * that the previous boot loader has enabled required clocks and
+ * setup the baud rate generator hardware for us already.
+ */
+ max_baud = port->uartclk ? port->uartclk / 16 : 115200;
+
+ baud = uart_get_baud_rate(port, termios, old, 0, max_baud);
+ if (likely(baud && port->uartclk))
+ t = sci_scbrr_calc(s->scbrr_algo_id, baud, port->uartclk);
+
+ do {
+ status = sci_in(port, SCxSR);
+ } while (!(status & SCxSR_TEND(port)));
+
+ sci_out(port, SCSCR, 0x00); /* TE=0, RE=0, CKE1=0 */
+
+ if (port->type != PORT_SCI)
+ sci_out(port, SCFCR, scfcr | SCFCR_RFRST | SCFCR_TFRST);
+
+ smr_val = sci_in(port, SCSMR) & 3;
+ if ((termios->c_cflag & CSIZE) == CS7)
+ smr_val |= 0x40;
+ if (termios->c_cflag & PARENB)
+ smr_val |= 0x20;
+ if (termios->c_cflag & PARODD)
+ smr_val |= 0x30;
+ if (termios->c_cflag & CSTOPB)
+ smr_val |= 0x08;
+
+ uart_update_timeout(port, termios->c_cflag, baud);
+
+ sci_out(port, SCSMR, smr_val);
+
+ dev_dbg(port->dev, "%s: SMR %x, t %x, SCSCR %x\n", __func__, smr_val, t,
+ s->scscr);
+
+ if (t > 0) {
+ if (t >= 256) {
+ sci_out(port, SCSMR, (sci_in(port, SCSMR) & ~3) | 1);
+ t >>= 2;
+ } else
+ sci_out(port, SCSMR, sci_in(port, SCSMR) & ~3);
+
+ sci_out(port, SCBRR, t);
+ udelay((1000000+(baud-1)) / baud); /* Wait one bit interval */
+ }
+
+ sci_init_pins(port, termios->c_cflag);
+ sci_out(port, SCFCR, scfcr | ((termios->c_cflag & CRTSCTS) ? SCFCR_MCE : 0));
+
+ sci_out(port, SCSCR, s->scscr);
+
+#ifdef CONFIG_SERIAL_SH_SCI_DMA
+ /*
+ * Calculate delay for 1.5 DMA buffers: see
+ * drivers/serial/serial_core.c::uart_update_timeout(). With 10 bits
+ * (CS8), 250Hz, 115200 baud and 64 bytes FIFO, the above function
+ * calculates 1 jiffie for the data plus 5 jiffies for the "slop(e)."
+ * Then below we calculate 3 jiffies (12ms) for 1.5 DMA buffers (3 FIFO
+ * sizes), but it has been found out experimentally, that this is not
+ * enough: the driver too often needlessly runs on a DMA timeout. 20ms
+ * as a minimum seem to work perfectly.
+ */
+ if (s->chan_rx) {
+ s->rx_timeout = (port->timeout - HZ / 50) * s->buf_len_rx * 3 /
+ port->fifosize / 2;
+ dev_dbg(port->dev,
+ "DMA Rx t-out %ums, tty t-out %u jiffies\n",
+ s->rx_timeout * 1000 / HZ, port->timeout);
+ if (s->rx_timeout < msecs_to_jiffies(20))
+ s->rx_timeout = msecs_to_jiffies(20);
+ }
+#endif
+
+ if ((termios->c_cflag & CREAD) != 0)
+ sci_start_rx(port);
+}
+
+static const char *sci_type(struct uart_port *port)
+{
+ switch (port->type) {
+ case PORT_IRDA:
+ return "irda";
+ case PORT_SCI:
+ return "sci";
+ case PORT_SCIF:
+ return "scif";
+ case PORT_SCIFA:
+ return "scifa";
+ case PORT_SCIFB:
+ return "scifb";
+ }
+
+ return NULL;
+}
+
+static void sci_release_port(struct uart_port *port)
+{
+ /* Nothing here yet .. */
+}
+
+static int sci_request_port(struct uart_port *port)
+{
+ /* Nothing here yet .. */
+ return 0;
+}
+
+static void sci_config_port(struct uart_port *port, int flags)
+{
+ struct sci_port *s = to_sci_port(port);
+
+ port->type = s->type;
+
+ if (port->membase)
+ return;
+
+ if (port->flags & UPF_IOREMAP) {
+ port->membase = ioremap_nocache(port->mapbase, 0x40);
+
+ if (IS_ERR(port->membase))
+ dev_err(port->dev, "can't remap port#%d\n", port->line);
+ } else {
+ /*
+ * For the simple (and majority of) cases where we don't
+ * need to do any remapping, just cast the cookie
+ * directly.
+ */
+ port->membase = (void __iomem *)port->mapbase;
+ }
+}
+
+static int sci_verify_port(struct uart_port *port, struct serial_struct *ser)
+{
+ struct sci_port *s = to_sci_port(port);
+
+ if (ser->irq != s->irqs[SCIx_TXI_IRQ] || ser->irq > nr_irqs)
+ return -EINVAL;
+ if (ser->baud_base < 2400)
+ /* No paper tape reader for Mitch.. */
+ return -EINVAL;
+
+ return 0;
+}
+
+static struct uart_ops sci_uart_ops = {
+ .tx_empty = sci_tx_empty,
+ .set_mctrl = sci_set_mctrl,
+ .get_mctrl = sci_get_mctrl,
+ .start_tx = sci_start_tx,
+ .stop_tx = sci_stop_tx,
+ .stop_rx = sci_stop_rx,
+ .enable_ms = sci_enable_ms,
+ .break_ctl = sci_break_ctl,
+ .startup = sci_startup,
+ .shutdown = sci_shutdown,
+ .set_termios = sci_set_termios,
+ .type = sci_type,
+ .release_port = sci_release_port,
+ .request_port = sci_request_port,
+ .config_port = sci_config_port,
+ .verify_port = sci_verify_port,
+#ifdef CONFIG_CONSOLE_POLL
+ .poll_get_char = sci_poll_get_char,
+ .poll_put_char = sci_poll_put_char,
+#endif
+};
+
+static int __devinit sci_init_single(struct platform_device *dev,
+ struct sci_port *sci_port,
+ unsigned int index,
+ struct plat_sci_port *p)
+{
+ struct uart_port *port = &sci_port->port;
+
+ port->ops = &sci_uart_ops;
+ port->iotype = UPIO_MEM;
+ port->line = index;
+
+ switch (p->type) {
+ case PORT_SCIFB:
+ port->fifosize = 256;
+ break;
+ case PORT_SCIFA:
+ port->fifosize = 64;
+ break;
+ case PORT_SCIF:
+ port->fifosize = 16;
+ break;
+ default:
+ port->fifosize = 1;
+ break;
+ }
+
+ if (dev) {
+ sci_port->iclk = clk_get(&dev->dev, "sci_ick");
+ if (IS_ERR(sci_port->iclk)) {
+ sci_port->iclk = clk_get(&dev->dev, "peripheral_clk");
+ if (IS_ERR(sci_port->iclk)) {
+ dev_err(&dev->dev, "can't get iclk\n");
+ return PTR_ERR(sci_port->iclk);
+ }
+ }
+
+ /*
+ * The function clock is optional, ignore it if we can't
+ * find it.
+ */
+ sci_port->fclk = clk_get(&dev->dev, "sci_fck");
+ if (IS_ERR(sci_port->fclk))
+ sci_port->fclk = NULL;
+
+ sci_port->enable = sci_clk_enable;
+ sci_port->disable = sci_clk_disable;
+ port->dev = &dev->dev;
+ }
+
+ sci_port->break_timer.data = (unsigned long)sci_port;
+ sci_port->break_timer.function = sci_break_timer;
+ init_timer(&sci_port->break_timer);
+
+ port->mapbase = p->mapbase;
+ port->membase = p->membase;
+
+ port->irq = p->irqs[SCIx_TXI_IRQ];
+ port->flags = p->flags;
+ sci_port->type = port->type = p->type;
+ sci_port->scscr = p->scscr;
+ sci_port->scbrr_algo_id = p->scbrr_algo_id;
+
+#ifdef CONFIG_SERIAL_SH_SCI_DMA
+ sci_port->dma_dev = p->dma_dev;
+ sci_port->slave_tx = p->dma_slave_tx;
+ sci_port->slave_rx = p->dma_slave_rx;
+
+ dev_dbg(port->dev, "%s: DMA device %p, tx %d, rx %d\n", __func__,
+ p->dma_dev, p->dma_slave_tx, p->dma_slave_rx);
+#endif
+
+ memcpy(&sci_port->irqs, &p->irqs, sizeof(p->irqs));
+ return 0;
+}
+
+#ifdef CONFIG_SERIAL_SH_SCI_CONSOLE
+static struct tty_driver *serial_console_device(struct console *co, int *index)
+{
+ struct uart_driver *p = &sci_uart_driver;
+ *index = co->index;
+ return p->tty_driver;
+}
+
+static void serial_console_putchar(struct uart_port *port, int ch)
+{
+ sci_poll_put_char(port, ch);
+}
+
+/*
+ * Print a string to the serial port trying not to disturb
+ * any possible real use of the port...
+ */
+static void serial_console_write(struct console *co, const char *s,
+ unsigned count)
+{
+ struct uart_port *port = co->data;
+ struct sci_port *sci_port = to_sci_port(port);
+ unsigned short bits;
+
+ if (sci_port->enable)
+ sci_port->enable(port);
+
+ uart_console_write(port, s, count, serial_console_putchar);
+
+ /* wait until fifo is empty and last bit has been transmitted */
+ bits = SCxSR_TDxE(port) | SCxSR_TEND(port);
+ while ((sci_in(port, SCxSR) & bits) != bits)
+ cpu_relax();
+
+ if (sci_port->disable)
+ sci_port->disable(port);
+}
+
+static int __devinit serial_console_setup(struct console *co, char *options)
+{
+ struct sci_port *sci_port;
+ struct uart_port *port;
+ int baud = 115200;
+ int bits = 8;
+ int parity = 'n';
+ int flow = 'n';
+ int ret;
+
+ /*
+ * 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 >= SCI_NPORTS)
+ co->index = 0;
+
+ if (co->data) {
+ port = co->data;
+ sci_port = to_sci_port(port);
+ } else {
+ sci_port = &sci_ports[co->index];
+ port = &sci_port->port;
+ co->data = port;
+ }
+
+ /*
+ * Also need to check port->type, we don't actually have any
+ * UPIO_PORT ports, but uart_report_port() handily misreports
+ * it anyways if we don't have a port available by the time this is
+ * called.
+ */
+ if (!port->type)
+ return -ENODEV;
+
+ sci_config_port(port, 0);
+
+ if (sci_port->enable)
+ sci_port->enable(port);
+
+ if (options)
+ uart_parse_options(options, &baud, &parity, &bits, &flow);
+
+ ret = uart_set_options(port, co, baud, parity, bits, flow);
+#if defined(__H8300H__) || defined(__H8300S__)
+ /* disable rx interrupt */
+ if (ret == 0)
+ sci_stop_rx(port);
+#endif
+ /* TODO: disable clock */
+ return ret;
+}
+
+static struct console serial_console = {
+ .name = "ttySC",
+ .device = serial_console_device,
+ .write = serial_console_write,
+ .setup = serial_console_setup,
+ .flags = CON_PRINTBUFFER,
+ .index = -1,
+};
+
+static int __init sci_console_init(void)
+{
+ register_console(&serial_console);
+ return 0;
+}
+console_initcall(sci_console_init);
+
+static struct sci_port early_serial_port;
+static struct console early_serial_console = {
+ .name = "early_ttySC",
+ .write = serial_console_write,
+ .flags = CON_PRINTBUFFER,
+};
+static char early_serial_buf[32];
+
+#endif /* CONFIG_SERIAL_SH_SCI_CONSOLE */
+
+#if defined(CONFIG_SERIAL_SH_SCI_CONSOLE)
+#define SCI_CONSOLE (&serial_console)
+#else
+#define SCI_CONSOLE 0
+#endif
+
+static char banner[] __initdata =
+ KERN_INFO "SuperH SCI(F) driver initialized\n";
+
+static struct uart_driver sci_uart_driver = {
+ .owner = THIS_MODULE,
+ .driver_name = "sci",
+ .dev_name = "ttySC",
+ .major = SCI_MAJOR,
+ .minor = SCI_MINOR_START,
+ .nr = SCI_NPORTS,
+ .cons = SCI_CONSOLE,
+};
+
+
+static int sci_remove(struct platform_device *dev)
+{
+ struct sh_sci_priv *priv = platform_get_drvdata(dev);
+ struct sci_port *p;
+ unsigned long flags;
+
+ cpufreq_unregister_notifier(&priv->clk_nb, CPUFREQ_TRANSITION_NOTIFIER);
+
+ spin_lock_irqsave(&priv->lock, flags);
+ list_for_each_entry(p, &priv->ports, node) {
+ uart_remove_one_port(&sci_uart_driver, &p->port);
+ clk_put(p->iclk);
+ clk_put(p->fclk);
+ }
+ spin_unlock_irqrestore(&priv->lock, flags);
+
+ kfree(priv);
+ return 0;
+}
+
+static int __devinit sci_probe_single(struct platform_device *dev,
+ unsigned int index,
+ struct plat_sci_port *p,
+ struct sci_port *sciport)
+{
+ struct sh_sci_priv *priv = platform_get_drvdata(dev);
+ unsigned long flags;
+ int ret;
+
+ /* Sanity check */
+ if (unlikely(index >= SCI_NPORTS)) {
+ dev_notice(&dev->dev, "Attempting to register port "
+ "%d when only %d are available.\n",
+ index+1, SCI_NPORTS);
+ dev_notice(&dev->dev, "Consider bumping "
+ "CONFIG_SERIAL_SH_SCI_NR_UARTS!\n");
+ return 0;
+ }
+
+ ret = sci_init_single(dev, sciport, index, p);
+ if (ret)
+ return ret;
+
+ ret = uart_add_one_port(&sci_uart_driver, &sciport->port);
+ if (ret)
+ return ret;
+
+ INIT_LIST_HEAD(&sciport->node);
+
+ spin_lock_irqsave(&priv->lock, flags);
+ list_add(&sciport->node, &priv->ports);
+ spin_unlock_irqrestore(&priv->lock, flags);
+
+ return 0;
+}
+
+/*
+ * Register a set of serial devices attached to a platform device. The
+ * list is terminated with a zero flags entry, which means we expect
+ * all entries to have at least UPF_BOOT_AUTOCONF set. Platforms that need
+ * remapping (such as sh64) should also set UPF_IOREMAP.
+ */
+static int __devinit sci_probe(struct platform_device *dev)
+{
+ struct plat_sci_port *p = dev->dev.platform_data;
+ struct sh_sci_priv *priv;
+ int i, ret = -EINVAL;
+
+#ifdef CONFIG_SERIAL_SH_SCI_CONSOLE
+ if (is_early_platform_device(dev)) {
+ if (dev->id == -1)
+ return -ENOTSUPP;
+ early_serial_console.index = dev->id;
+ early_serial_console.data = &early_serial_port.port;
+ sci_init_single(NULL, &early_serial_port, dev->id, p);
+ serial_console_setup(&early_serial_console, early_serial_buf);
+ if (!strstr(early_serial_buf, "keep"))
+ early_serial_console.flags |= CON_BOOT;
+ register_console(&early_serial_console);
+ return 0;
+ }
+#endif
+
+ priv = kzalloc(sizeof(*priv), GFP_KERNEL);
+ if (!priv)
+ return -ENOMEM;
+
+ INIT_LIST_HEAD(&priv->ports);
+ spin_lock_init(&priv->lock);
+ platform_set_drvdata(dev, priv);
+
+ priv->clk_nb.notifier_call = sci_notifier;
+ cpufreq_register_notifier(&priv->clk_nb, CPUFREQ_TRANSITION_NOTIFIER);
+
+ if (dev->id != -1) {
+ ret = sci_probe_single(dev, dev->id, p, &sci_ports[dev->id]);
+ if (ret)
+ goto err_unreg;
+ } else {
+ for (i = 0; p && p->flags != 0; p++, i++) {
+ ret = sci_probe_single(dev, i, p, &sci_ports[i]);
+ if (ret)
+ goto err_unreg;
+ }
+ }
+
+#ifdef CONFIG_SH_STANDARD_BIOS
+ sh_bios_gdb_detach();
+#endif
+
+ return 0;
+
+err_unreg:
+ sci_remove(dev);
+ return ret;
+}
+
+static int sci_suspend(struct device *dev)
+{
+ struct sh_sci_priv *priv = dev_get_drvdata(dev);
+ struct sci_port *p;
+ unsigned long flags;
+
+ spin_lock_irqsave(&priv->lock, flags);
+ list_for_each_entry(p, &priv->ports, node)
+ uart_suspend_port(&sci_uart_driver, &p->port);
+ spin_unlock_irqrestore(&priv->lock, flags);
+
+ return 0;
+}
+
+static int sci_resume(struct device *dev)
+{
+ struct sh_sci_priv *priv = dev_get_drvdata(dev);
+ struct sci_port *p;
+ unsigned long flags;
+
+ spin_lock_irqsave(&priv->lock, flags);
+ list_for_each_entry(p, &priv->ports, node)
+ uart_resume_port(&sci_uart_driver, &p->port);
+ spin_unlock_irqrestore(&priv->lock, flags);
+
+ return 0;
+}
+
+static const struct dev_pm_ops sci_dev_pm_ops = {
+ .suspend = sci_suspend,
+ .resume = sci_resume,
+};
+
+static struct platform_driver sci_driver = {
+ .probe = sci_probe,
+ .remove = sci_remove,
+ .driver = {
+ .name = "sh-sci",
+ .owner = THIS_MODULE,
+ .pm = &sci_dev_pm_ops,
+ },
+};
+
+static int __init sci_init(void)
+{
+ int ret;
+
+ printk(banner);
+
+ ret = uart_register_driver(&sci_uart_driver);
+ if (likely(ret == 0)) {
+ ret = platform_driver_register(&sci_driver);
+ if (unlikely(ret))
+ uart_unregister_driver(&sci_uart_driver);
+ }
+
+ return ret;
+}
+
+static void __exit sci_exit(void)
+{
+ platform_driver_unregister(&sci_driver);
+ uart_unregister_driver(&sci_uart_driver);
+}
+
+#ifdef CONFIG_SERIAL_SH_SCI_CONSOLE
+early_platform_init_buffer("earlyprintk", &sci_driver,
+ early_serial_buf, ARRAY_SIZE(early_serial_buf));
+#endif
+module_init(sci_init);
+module_exit(sci_exit);
+
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:sh-sci");