diff options
Diffstat (limited to 'kernel/drivers/tty/serial/sh-sci.c')
| -rw-r--r-- | kernel/drivers/tty/serial/sh-sci.c | 2730 |
1 files changed, 2730 insertions, 0 deletions
diff --git a/kernel/drivers/tty/serial/sh-sci.c b/kernel/drivers/tty/serial/sh-sci.c new file mode 100644 index 000000000..e7d6566fa --- /dev/null +++ b/kernel/drivers/tty/serial/sh-sci.c @@ -0,0 +1,2730 @@ +/* + * 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/clk.h> +#include <linux/console.h> +#include <linux/ctype.h> +#include <linux/cpufreq.h> +#include <linux/delay.h> +#include <linux/dmaengine.h> +#include <linux/dma-mapping.h> +#include <linux/err.h> +#include <linux/errno.h> +#include <linux/init.h> +#include <linux/interrupt.h> +#include <linux/ioport.h> +#include <linux/major.h> +#include <linux/module.h> +#include <linux/mm.h> +#include <linux/notifier.h> +#include <linux/of.h> +#include <linux/platform_device.h> +#include <linux/pm_runtime.h> +#include <linux/scatterlist.h> +#include <linux/serial.h> +#include <linux/serial_sci.h> +#include <linux/sh_dma.h> +#include <linux/slab.h> +#include <linux/string.h> +#include <linux/sysrq.h> +#include <linux/timer.h> +#include <linux/tty.h> +#include <linux/tty_flip.h> + +#ifdef CONFIG_SUPERH +#include <asm/sh_bios.h> +#endif + +#include "sh-sci.h" + +/* Offsets into the sci_port->irqs array */ +enum { + SCIx_ERI_IRQ, + SCIx_RXI_IRQ, + SCIx_TXI_IRQ, + SCIx_BRI_IRQ, + SCIx_NR_IRQS, + + SCIx_MUX_IRQ = SCIx_NR_IRQS, /* special case */ +}; + +#define SCIx_IRQ_IS_MUXED(port) \ + ((port)->irqs[SCIx_ERI_IRQ] == \ + (port)->irqs[SCIx_RXI_IRQ]) || \ + ((port)->irqs[SCIx_ERI_IRQ] && \ + ((port)->irqs[SCIx_RXI_IRQ] < 0)) + +struct sci_port { + struct uart_port port; + + /* Platform configuration */ + struct plat_sci_port *cfg; + int overrun_bit; + unsigned int error_mask; + unsigned int sampling_rate; + + + /* Break timer */ + struct timer_list break_timer; + int break_flag; + + /* Interface clock */ + struct clk *iclk; + /* Function clock */ + struct clk *fclk; + + int irqs[SCIx_NR_IRQS]; + char *irqstr[SCIx_NR_IRQS]; + + struct dma_chan *chan_tx; + struct dma_chan *chan_rx; + +#ifdef CONFIG_SERIAL_SH_SCI_DMA + 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 notifier_block freq_transition; +}; + +/* Function prototypes */ +static void sci_start_tx(struct uart_port *port); +static void sci_stop_tx(struct uart_port *port); +static void sci_start_rx(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); +} + +struct plat_sci_reg { + u8 offset, size; +}; + +/* Helper for invalidating specific entries of an inherited map. */ +#define sci_reg_invalid { .offset = 0, .size = 0 } + +static struct plat_sci_reg sci_regmap[SCIx_NR_REGTYPES][SCIx_NR_REGS] = { + [SCIx_PROBE_REGTYPE] = { + [0 ... SCIx_NR_REGS - 1] = sci_reg_invalid, + }, + + /* + * Common SCI definitions, dependent on the port's regshift + * value. + */ + [SCIx_SCI_REGTYPE] = { + [SCSMR] = { 0x00, 8 }, + [SCBRR] = { 0x01, 8 }, + [SCSCR] = { 0x02, 8 }, + [SCxTDR] = { 0x03, 8 }, + [SCxSR] = { 0x04, 8 }, + [SCxRDR] = { 0x05, 8 }, + [SCFCR] = sci_reg_invalid, + [SCFDR] = sci_reg_invalid, + [SCTFDR] = sci_reg_invalid, + [SCRFDR] = sci_reg_invalid, + [SCSPTR] = sci_reg_invalid, + [SCLSR] = sci_reg_invalid, + [HSSRR] = sci_reg_invalid, + }, + + /* + * Common definitions for legacy IrDA ports, dependent on + * regshift value. + */ + [SCIx_IRDA_REGTYPE] = { + [SCSMR] = { 0x00, 8 }, + [SCBRR] = { 0x01, 8 }, + [SCSCR] = { 0x02, 8 }, + [SCxTDR] = { 0x03, 8 }, + [SCxSR] = { 0x04, 8 }, + [SCxRDR] = { 0x05, 8 }, + [SCFCR] = { 0x06, 8 }, + [SCFDR] = { 0x07, 16 }, + [SCTFDR] = sci_reg_invalid, + [SCRFDR] = sci_reg_invalid, + [SCSPTR] = sci_reg_invalid, + [SCLSR] = sci_reg_invalid, + [HSSRR] = sci_reg_invalid, + }, + + /* + * Common SCIFA definitions. + */ + [SCIx_SCIFA_REGTYPE] = { + [SCSMR] = { 0x00, 16 }, + [SCBRR] = { 0x04, 8 }, + [SCSCR] = { 0x08, 16 }, + [SCxTDR] = { 0x20, 8 }, + [SCxSR] = { 0x14, 16 }, + [SCxRDR] = { 0x24, 8 }, + [SCFCR] = { 0x18, 16 }, + [SCFDR] = { 0x1c, 16 }, + [SCTFDR] = sci_reg_invalid, + [SCRFDR] = sci_reg_invalid, + [SCSPTR] = sci_reg_invalid, + [SCLSR] = sci_reg_invalid, + [HSSRR] = sci_reg_invalid, + }, + + /* + * Common SCIFB definitions. + */ + [SCIx_SCIFB_REGTYPE] = { + [SCSMR] = { 0x00, 16 }, + [SCBRR] = { 0x04, 8 }, + [SCSCR] = { 0x08, 16 }, + [SCxTDR] = { 0x40, 8 }, + [SCxSR] = { 0x14, 16 }, + [SCxRDR] = { 0x60, 8 }, + [SCFCR] = { 0x18, 16 }, + [SCFDR] = sci_reg_invalid, + [SCTFDR] = { 0x38, 16 }, + [SCRFDR] = { 0x3c, 16 }, + [SCSPTR] = sci_reg_invalid, + [SCLSR] = sci_reg_invalid, + [HSSRR] = sci_reg_invalid, + }, + + /* + * Common SH-2(A) SCIF definitions for ports with FIFO data + * count registers. + */ + [SCIx_SH2_SCIF_FIFODATA_REGTYPE] = { + [SCSMR] = { 0x00, 16 }, + [SCBRR] = { 0x04, 8 }, + [SCSCR] = { 0x08, 16 }, + [SCxTDR] = { 0x0c, 8 }, + [SCxSR] = { 0x10, 16 }, + [SCxRDR] = { 0x14, 8 }, + [SCFCR] = { 0x18, 16 }, + [SCFDR] = { 0x1c, 16 }, + [SCTFDR] = sci_reg_invalid, + [SCRFDR] = sci_reg_invalid, + [SCSPTR] = { 0x20, 16 }, + [SCLSR] = { 0x24, 16 }, + [HSSRR] = sci_reg_invalid, + }, + + /* + * Common SH-3 SCIF definitions. + */ + [SCIx_SH3_SCIF_REGTYPE] = { + [SCSMR] = { 0x00, 8 }, + [SCBRR] = { 0x02, 8 }, + [SCSCR] = { 0x04, 8 }, + [SCxTDR] = { 0x06, 8 }, + [SCxSR] = { 0x08, 16 }, + [SCxRDR] = { 0x0a, 8 }, + [SCFCR] = { 0x0c, 8 }, + [SCFDR] = { 0x0e, 16 }, + [SCTFDR] = sci_reg_invalid, + [SCRFDR] = sci_reg_invalid, + [SCSPTR] = sci_reg_invalid, + [SCLSR] = sci_reg_invalid, + [HSSRR] = sci_reg_invalid, + }, + + /* + * Common SH-4(A) SCIF(B) definitions. + */ + [SCIx_SH4_SCIF_REGTYPE] = { + [SCSMR] = { 0x00, 16 }, + [SCBRR] = { 0x04, 8 }, + [SCSCR] = { 0x08, 16 }, + [SCxTDR] = { 0x0c, 8 }, + [SCxSR] = { 0x10, 16 }, + [SCxRDR] = { 0x14, 8 }, + [SCFCR] = { 0x18, 16 }, + [SCFDR] = { 0x1c, 16 }, + [SCTFDR] = sci_reg_invalid, + [SCRFDR] = sci_reg_invalid, + [SCSPTR] = { 0x20, 16 }, + [SCLSR] = { 0x24, 16 }, + [HSSRR] = sci_reg_invalid, + }, + + /* + * Common HSCIF definitions. + */ + [SCIx_HSCIF_REGTYPE] = { + [SCSMR] = { 0x00, 16 }, + [SCBRR] = { 0x04, 8 }, + [SCSCR] = { 0x08, 16 }, + [SCxTDR] = { 0x0c, 8 }, + [SCxSR] = { 0x10, 16 }, + [SCxRDR] = { 0x14, 8 }, + [SCFCR] = { 0x18, 16 }, + [SCFDR] = { 0x1c, 16 }, + [SCTFDR] = sci_reg_invalid, + [SCRFDR] = sci_reg_invalid, + [SCSPTR] = { 0x20, 16 }, + [SCLSR] = { 0x24, 16 }, + [HSSRR] = { 0x40, 16 }, + }, + + /* + * Common SH-4(A) SCIF(B) definitions for ports without an SCSPTR + * register. + */ + [SCIx_SH4_SCIF_NO_SCSPTR_REGTYPE] = { + [SCSMR] = { 0x00, 16 }, + [SCBRR] = { 0x04, 8 }, + [SCSCR] = { 0x08, 16 }, + [SCxTDR] = { 0x0c, 8 }, + [SCxSR] = { 0x10, 16 }, + [SCxRDR] = { 0x14, 8 }, + [SCFCR] = { 0x18, 16 }, + [SCFDR] = { 0x1c, 16 }, + [SCTFDR] = sci_reg_invalid, + [SCRFDR] = sci_reg_invalid, + [SCSPTR] = sci_reg_invalid, + [SCLSR] = { 0x24, 16 }, + [HSSRR] = sci_reg_invalid, + }, + + /* + * Common SH-4(A) SCIF(B) definitions for ports with FIFO data + * count registers. + */ + [SCIx_SH4_SCIF_FIFODATA_REGTYPE] = { + [SCSMR] = { 0x00, 16 }, + [SCBRR] = { 0x04, 8 }, + [SCSCR] = { 0x08, 16 }, + [SCxTDR] = { 0x0c, 8 }, + [SCxSR] = { 0x10, 16 }, + [SCxRDR] = { 0x14, 8 }, + [SCFCR] = { 0x18, 16 }, + [SCFDR] = { 0x1c, 16 }, + [SCTFDR] = { 0x1c, 16 }, /* aliased to SCFDR */ + [SCRFDR] = { 0x20, 16 }, + [SCSPTR] = { 0x24, 16 }, + [SCLSR] = { 0x28, 16 }, + [HSSRR] = sci_reg_invalid, + }, + + /* + * SH7705-style SCIF(B) ports, lacking both SCSPTR and SCLSR + * registers. + */ + [SCIx_SH7705_SCIF_REGTYPE] = { + [SCSMR] = { 0x00, 16 }, + [SCBRR] = { 0x04, 8 }, + [SCSCR] = { 0x08, 16 }, + [SCxTDR] = { 0x20, 8 }, + [SCxSR] = { 0x14, 16 }, + [SCxRDR] = { 0x24, 8 }, + [SCFCR] = { 0x18, 16 }, + [SCFDR] = { 0x1c, 16 }, + [SCTFDR] = sci_reg_invalid, + [SCRFDR] = sci_reg_invalid, + [SCSPTR] = sci_reg_invalid, + [SCLSR] = sci_reg_invalid, + [HSSRR] = sci_reg_invalid, + }, +}; + +#define sci_getreg(up, offset) (sci_regmap[to_sci_port(up)->cfg->regtype] + offset) + +/* + * The "offset" here is rather misleading, in that it refers to an enum + * value relative to the port mapping rather than the fixed offset + * itself, which needs to be manually retrieved from the platform's + * register map for the given port. + */ +static unsigned int sci_serial_in(struct uart_port *p, int offset) +{ + struct plat_sci_reg *reg = sci_getreg(p, offset); + + if (reg->size == 8) + return ioread8(p->membase + (reg->offset << p->regshift)); + else if (reg->size == 16) + return ioread16(p->membase + (reg->offset << p->regshift)); + else + WARN(1, "Invalid register access\n"); + + return 0; +} + +static void sci_serial_out(struct uart_port *p, int offset, int value) +{ + struct plat_sci_reg *reg = sci_getreg(p, offset); + + if (reg->size == 8) + iowrite8(value, p->membase + (reg->offset << p->regshift)); + else if (reg->size == 16) + iowrite16(value, p->membase + (reg->offset << p->regshift)); + else + WARN(1, "Invalid register access\n"); +} + +static int sci_probe_regmap(struct plat_sci_port *cfg) +{ + switch (cfg->type) { + case PORT_SCI: + cfg->regtype = SCIx_SCI_REGTYPE; + break; + case PORT_IRDA: + cfg->regtype = SCIx_IRDA_REGTYPE; + break; + case PORT_SCIFA: + cfg->regtype = SCIx_SCIFA_REGTYPE; + break; + case PORT_SCIFB: + cfg->regtype = SCIx_SCIFB_REGTYPE; + break; + case PORT_SCIF: + /* + * The SH-4 is a bit of a misnomer here, although that's + * where this particular port layout originated. This + * configuration (or some slight variation thereof) + * remains the dominant model for all SCIFs. + */ + cfg->regtype = SCIx_SH4_SCIF_REGTYPE; + break; + case PORT_HSCIF: + cfg->regtype = SCIx_HSCIF_REGTYPE; + break; + default: + pr_err("Can't probe register map for given port\n"); + return -EINVAL; + } + + return 0; +} + +static void sci_port_enable(struct sci_port *sci_port) +{ + if (!sci_port->port.dev) + return; + + pm_runtime_get_sync(sci_port->port.dev); + + clk_prepare_enable(sci_port->iclk); + sci_port->port.uartclk = clk_get_rate(sci_port->iclk); + clk_prepare_enable(sci_port->fclk); +} + +static void sci_port_disable(struct sci_port *sci_port) +{ + if (!sci_port->port.dev) + return; + + /* Cancel the break timer to ensure that the timer handler will not try + * to access the hardware with clocks and power disabled. Reset the + * break flag to make the break debouncing state machine ready for the + * next break. + */ + del_timer_sync(&sci_port->break_timer); + sci_port->break_flag = 0; + + clk_disable_unprepare(sci_port->fclk); + clk_disable_unprepare(sci_port->iclk); + + pm_runtime_put_sync(sci_port->port.dev); +} + +#if defined(CONFIG_CONSOLE_POLL) || defined(CONFIG_SERIAL_SH_SCI_CONSOLE) + +#ifdef CONFIG_CONSOLE_POLL +static int sci_poll_get_char(struct uart_port *port) +{ + unsigned short status; + int c; + + do { + status = serial_port_in(port, SCxSR); + if (status & SCxSR_ERRORS(port)) { + serial_port_out(port, SCxSR, SCxSR_ERROR_CLEAR(port)); + continue; + } + break; + } while (1); + + if (!(status & SCxSR_RDxF(port))) + return NO_POLL_CHAR; + + c = serial_port_in(port, SCxRDR); + + /* Dummy read */ + serial_port_in(port, SCxSR); + serial_port_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 = serial_port_in(port, SCxSR); + } while (!(status & SCxSR_TDxE(port))); + + serial_port_out(port, SCxTDR, c); + serial_port_out(port, SCxSR, SCxSR_TDxE_CLEAR(port) & ~SCxSR_TEND(port)); +} +#endif /* CONFIG_CONSOLE_POLL || CONFIG_SERIAL_SH_SCI_CONSOLE */ + +static void sci_init_pins(struct uart_port *port, unsigned int cflag) +{ + struct sci_port *s = to_sci_port(port); + struct plat_sci_reg *reg = sci_regmap[s->cfg->regtype] + SCSPTR; + + /* + * Use port-specific handler if provided. + */ + if (s->cfg->ops && s->cfg->ops->init_pins) { + s->cfg->ops->init_pins(port, cflag); + return; + } + + /* + * For the generic path SCSPTR is necessary. Bail out if that's + * unavailable, too. + */ + if (!reg->size) + return; + + if ((s->cfg->capabilities & SCIx_HAVE_RTSCTS) && + ((!(cflag & CRTSCTS)))) { + unsigned short status; + + status = serial_port_in(port, SCSPTR); + status &= ~SCSPTR_CTSIO; + status |= SCSPTR_RTSIO; + serial_port_out(port, SCSPTR, status); /* Set RTS = 1 */ + } +} + +static int sci_txfill(struct uart_port *port) +{ + struct plat_sci_reg *reg; + + reg = sci_getreg(port, SCTFDR); + if (reg->size) + return serial_port_in(port, SCTFDR) & ((port->fifosize << 1) - 1); + + reg = sci_getreg(port, SCFDR); + if (reg->size) + return serial_port_in(port, SCFDR) >> 8; + + return !(serial_port_in(port, SCxSR) & SCI_TDRE); +} + +static int sci_txroom(struct uart_port *port) +{ + return port->fifosize - sci_txfill(port); +} + +static int sci_rxfill(struct uart_port *port) +{ + struct plat_sci_reg *reg; + + reg = sci_getreg(port, SCRFDR); + if (reg->size) + return serial_port_in(port, SCRFDR) & ((port->fifosize << 1) - 1); + + reg = sci_getreg(port, SCFDR); + if (reg->size) + return serial_port_in(port, SCFDR) & ((port->fifosize << 1) - 1); + + return (serial_port_in(port, SCxSR) & SCxSR_RDxF(port)) != 0; +} + +/* + * SCI helper for checking the state of the muxed port/RXD pins. + */ +static inline int sci_rxd_in(struct uart_port *port) +{ + struct sci_port *s = to_sci_port(port); + + if (s->cfg->port_reg <= 0) + return 1; + + /* Cast for ARM damage */ + return !!__raw_readb((void __iomem *)(uintptr_t)s->cfg->port_reg); +} + +/* ********************************************************************** * + * 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 = serial_port_in(port, SCxSR); + if (!(status & SCxSR_TDxE(port))) { + ctrl = serial_port_in(port, SCSCR); + if (uart_circ_empty(xmit)) + ctrl &= ~SCSCR_TIE; + else + ctrl |= SCSCR_TIE; + serial_port_out(port, SCSCR, ctrl); + return; + } + + count = sci_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; + } + + serial_port_out(port, SCxTDR, c); + + port->icount.tx++; + } while (--count > 0); + + serial_port_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 = serial_port_in(port, SCSCR); + + if (port->type != PORT_SCI) { + serial_port_in(port, SCxSR); /* Dummy read */ + serial_port_out(port, SCxSR, SCxSR_TDxE_CLEAR(port)); + } + + ctrl |= SCSCR_TIE; + serial_port_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 void sci_receive_chars(struct uart_port *port) +{ + struct sci_port *sci_port = to_sci_port(port); + struct tty_port *tport = &port->state->port; + int i, count, copied = 0; + unsigned short status; + unsigned char flag; + + status = serial_port_in(port, SCxSR); + if (!(status & SCxSR_RDxF(port))) + return; + + while (1) { + /* Don't copy more bytes than there is room for in the buffer */ + count = tty_buffer_request_room(tport, sci_rxfill(port)); + + /* If for any reason we can't copy more data, we're done! */ + if (count == 0) + break; + + if (port->type == PORT_SCI) { + char c = serial_port_in(port, SCxRDR); + if (uart_handle_sysrq_char(port, c) || + sci_port->break_flag) + count = 0; + else + tty_insert_flip_char(tport, c, TTY_NORMAL); + } else { + for (i = 0; i < count; i++) { + char c = serial_port_in(port, SCxRDR); + + status = serial_port_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; + port->icount.frame++; + dev_notice(port->dev, "frame error\n"); + } else if (status & SCxSR_PER(port)) { + flag = TTY_PARITY; + port->icount.parity++; + dev_notice(port->dev, "parity error\n"); + } else + flag = TTY_NORMAL; + + tty_insert_flip_char(tport, c, flag); + } + } + + serial_port_in(port, SCxSR); /* dummy read */ + serial_port_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(tport); + } else { + serial_port_in(port, SCxSR); /* dummy read */ + serial_port_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 inline void sci_schedule_break_timer(struct sci_port *port) +{ + mod_timer(&port->break_timer, jiffies + SCI_BREAK_JIFFIES); +} + +/* 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 int sci_handle_errors(struct uart_port *port) +{ + int copied = 0; + unsigned short status = serial_port_in(port, SCxSR); + struct tty_port *tport = &port->state->port; + struct sci_port *s = to_sci_port(port); + + /* Handle overruns */ + if (status & (1 << s->overrun_bit)) { + port->icount.overrun++; + + /* overrun error */ + if (tty_insert_flip_char(tport, 0, TTY_OVERRUN)) + copied++; + + dev_notice(port->dev, "overrun error\n"); + } + + 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) { + port->icount.brk++; + + 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(tport, 0, TTY_BREAK)) + copied++; + } + + } else { + /* frame error */ + port->icount.frame++; + + if (tty_insert_flip_char(tport, 0, TTY_FRAME)) + copied++; + + dev_notice(port->dev, "frame error\n"); + } + } + + if (status & SCxSR_PER(port)) { + /* parity error */ + port->icount.parity++; + + if (tty_insert_flip_char(tport, 0, TTY_PARITY)) + copied++; + + dev_notice(port->dev, "parity error\n"); + } + + if (copied) + tty_flip_buffer_push(tport); + + return copied; +} + +static int sci_handle_fifo_overrun(struct uart_port *port) +{ + struct tty_port *tport = &port->state->port; + struct sci_port *s = to_sci_port(port); + struct plat_sci_reg *reg; + int copied = 0, offset; + u16 status, bit; + + switch (port->type) { + case PORT_SCIF: + case PORT_HSCIF: + offset = SCLSR; + break; + case PORT_SCIFA: + case PORT_SCIFB: + offset = SCxSR; + break; + default: + return 0; + } + + reg = sci_getreg(port, offset); + if (!reg->size) + return 0; + + status = serial_port_in(port, offset); + bit = 1 << s->overrun_bit; + + if (status & bit) { + status &= ~bit; + serial_port_out(port, offset, status); + + port->icount.overrun++; + + tty_insert_flip_char(tport, 0, TTY_OVERRUN); + tty_flip_buffer_push(tport); + + dev_dbg(port->dev, "overrun error\n"); + copied++; + } + + return copied; +} + +static int sci_handle_breaks(struct uart_port *port) +{ + int copied = 0; + unsigned short status = serial_port_in(port, SCxSR); + struct tty_port *tport = &port->state->port; + 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 + + port->icount.brk++; + + /* Notify of BREAK */ + if (tty_insert_flip_char(tport, 0, TTY_BREAK)) + copied++; + + dev_dbg(port->dev, "BREAK detected\n"); + } + + if (copied) + tty_flip_buffer_push(tport); + + 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 = serial_port_in(port, SCSCR); + u16 ssr = serial_port_in(port, SCxSR); + + /* Disable future Rx interrupts */ + if (port->type == PORT_SCIFA || port->type == PORT_SCIFB) { + disable_irq_nosync(irq); + scr |= SCSCR_RDRQE; + } else { + scr &= ~SCSCR_RIE; + } + serial_port_out(port, SCSCR, scr); + /* Clear current interrupt */ + serial_port_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 */ + serial_port_in(port, SCxSR); + serial_port_out(port, SCxSR, SCxSR_RDxF_CLEAR(port)); + } + } else { + sci_handle_fifo_overrun(port); + sci_rx_interrupt(irq, ptr); + } + + serial_port_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); + serial_port_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)->cfg->scscr & SCSCR_REIE); +} + +static irqreturn_t sci_mpxed_interrupt(int irq, void *ptr) +{ + unsigned short ssr_status, scr_status, err_enabled, orer_status = 0; + struct uart_port *port = ptr; + struct sci_port *s = to_sci_port(port); + irqreturn_t ret = IRQ_NONE; + + ssr_status = serial_port_in(port, SCxSR); + scr_status = serial_port_in(port, SCSCR); + switch (port->type) { + case PORT_SCIF: + case PORT_HSCIF: + orer_status = serial_port_in(port, SCLSR); + break; + case PORT_SCIFA: + case PORT_SCIFB: + orer_status = ssr_status; + break; + } + + 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)) { + if (port->type == PORT_SCIF || port->type == PORT_HSCIF) + sci_handle_fifo_overrun(port); + 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); + + /* Overrun Interrupt */ + if (orer_status & (1 << s->overrun_bit)) + sci_handle_fifo_overrun(port); + + return ret; +} + +/* + * Here we define a transition 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 sci_port *sci_port; + unsigned long flags; + + sci_port = container_of(self, struct sci_port, freq_transition); + + if (phase == CPUFREQ_POSTCHANGE) { + struct uart_port *port = &sci_port->port; + + spin_lock_irqsave(&port->lock, flags); + port->uartclk = clk_get_rate(sci_port->iclk); + spin_unlock_irqrestore(&port->lock, flags); + } + + return NOTIFY_OK; +} + +static struct sci_irq_desc { + const char *desc; + irq_handler_t handler; +} sci_irq_desc[] = { + /* + * Split out handlers, the default case. + */ + [SCIx_ERI_IRQ] = { + .desc = "rx err", + .handler = sci_er_interrupt, + }, + + [SCIx_RXI_IRQ] = { + .desc = "rx full", + .handler = sci_rx_interrupt, + }, + + [SCIx_TXI_IRQ] = { + .desc = "tx empty", + .handler = sci_tx_interrupt, + }, + + [SCIx_BRI_IRQ] = { + .desc = "break", + .handler = sci_br_interrupt, + }, + + /* + * Special muxed handler. + */ + [SCIx_MUX_IRQ] = { + .desc = "mux", + .handler = sci_mpxed_interrupt, + }, +}; + +static int sci_request_irq(struct sci_port *port) +{ + struct uart_port *up = &port->port; + int i, j, ret = 0; + + for (i = j = 0; i < SCIx_NR_IRQS; i++, j++) { + struct sci_irq_desc *desc; + int irq; + + if (SCIx_IRQ_IS_MUXED(port)) { + i = SCIx_MUX_IRQ; + irq = up->irq; + } else { + irq = port->irqs[i]; + + /* + * Certain port types won't support all of the + * available interrupt sources. + */ + if (unlikely(irq < 0)) + continue; + } + + desc = sci_irq_desc + i; + port->irqstr[j] = kasprintf(GFP_KERNEL, "%s:%s", + dev_name(up->dev), desc->desc); + if (!port->irqstr[j]) { + dev_err(up->dev, "Failed to allocate %s IRQ string\n", + desc->desc); + goto out_nomem; + } + + ret = request_irq(irq, desc->handler, up->irqflags, + port->irqstr[j], port); + if (unlikely(ret)) { + dev_err(up->dev, "Can't allocate %s IRQ\n", desc->desc); + goto out_noirq; + } + } + + return 0; + +out_noirq: + while (--i >= 0) + free_irq(port->irqs[i], port); + +out_nomem: + while (--j >= 0) + kfree(port->irqstr[j]); + + return ret; +} + +static void sci_free_irq(struct sci_port *port) +{ + int i; + + /* + * Intentionally in reverse order so we iterate over the muxed + * IRQ first. + */ + for (i = 0; i < SCIx_NR_IRQS; i++) { + int irq = port->irqs[i]; + + /* + * Certain port types won't support all of the available + * interrupt sources. + */ + if (unlikely(irq < 0)) + continue; + + free_irq(port->irqs[i], port); + kfree(port->irqstr[i]); + + if (SCIx_IRQ_IS_MUXED(port)) { + /* If there's only one IRQ, we're done. */ + return; + } + } +} + +static unsigned int sci_tx_empty(struct uart_port *port) +{ + unsigned short status = serial_port_in(port, SCxSR); + unsigned short in_tx_fifo = sci_txfill(port); + + return (status & SCxSR_TEND(port)) && !in_tx_fifo ? TIOCSER_TEMT : 0; +} + +/* + * Modem control is a bit of a mixed bag for SCI(F) ports. Generally + * CTS/RTS is supported in hardware by at least one port and controlled + * via SCSPTR (SCxPCR for SCIFA/B parts), or external pins (presently + * handled via the ->init_pins() op, which is a bit of a one-way street, + * lacking any ability to defer pin control -- this will later be + * converted over to the GPIO framework). + * + * Other modes (such as loopback) are supported generically on certain + * port types, but not others. For these it's sufficient to test for the + * existence of the support register and simply ignore the port type. + */ +static void sci_set_mctrl(struct uart_port *port, unsigned int mctrl) +{ + if (mctrl & TIOCM_LOOP) { + struct plat_sci_reg *reg; + + /* + * Standard loopback mode for SCFCR ports. + */ + reg = sci_getreg(port, SCFCR); + if (reg->size) + serial_port_out(port, SCFCR, + serial_port_in(port, SCFCR) | + SCFCR_LOOP); + } +} + +static unsigned int sci_get_mctrl(struct uart_port *port) +{ + /* + * CTS/RTS is handled in hardware when supported, while nothing + * else is wired up. Keep it simple and simply assert DSR/CAR. + */ + return TIOCM_DSR | TIOCM_CAR; +} + +#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->desc_tx = NULL; + + if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS) + uart_write_wakeup(port); + + if (!uart_circ_empty(xmit)) { + s->cookie_tx = 0; + schedule_work(&s->work_tx); + } else { + s->cookie_tx = -EINVAL; + if (port->type == PORT_SCIFA || port->type == PORT_SCIFB) { + u16 ctrl = serial_port_in(port, SCSCR); + serial_port_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, size_t count) +{ + struct uart_port *port = &s->port; + struct tty_port *tport = &port->state->port; + int i, active, room; + + room = tty_buffer_request_room(tport, 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 %zu bytes\n", + count - room); + if (!room) + return room; + + for (i = 0; i < room; i++) + tty_insert_flip_char(tport, ((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; + 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, 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(&port->state->port); + + schedule_work(&s->work_rx); +} + +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 = dmaengine_prep_slave_sg(chan, + sg, 1, DMA_DEV_TO_MEM, 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_COMPLETE) { + /* Handle incomplete DMA receive */ + struct dma_chan *chan = s->chan_rx; + struct shdma_desc *sh_desc = container_of(desc, + struct shdma_desc, async_tx); + unsigned long flags; + int count; + + dmaengine_terminate_all(chan); + dev_dbg(port->dev, "Read %zu bytes with cookie %d\n", + sh_desc->partial, sh_desc->cookie); + + spin_lock_irqsave(&port->lock, flags); + count = sci_dma_rx_push(s, sh_desc->partial); + spin_unlock_irqrestore(&port->lock, flags); + + if (count) + tty_flip_buffer_push(&port->state->port); + + 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 = dmaengine_prep_slave_sg(chan, + sg, s->sg_len_tx, DMA_MEM_TO_DEV, + 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 = serial_port_in(port, SCSCR); + if (s->chan_tx) + new = scr | SCSCR_TDRQE; + else + new = scr & ~SCSCR_TDRQE; + if (new != scr) + serial_port_out(port, SCSCR, new); + } + + if (s->chan_tx && !uart_circ_empty(&s->port.state->xmit) && + s->cookie_tx < 0) { + 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 = serial_port_in(port, SCSCR); + serial_port_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 = serial_port_in(port, SCSCR); + + if (port->type == PORT_SCIFA || port->type == PORT_SCIFB) + ctrl &= ~SCSCR_TDRQE; + + ctrl &= ~SCSCR_TIE; + + serial_port_out(port, SCSCR, ctrl); +} + +static void sci_start_rx(struct uart_port *port) +{ + unsigned short ctrl; + + ctrl = serial_port_in(port, SCSCR) | port_rx_irq_mask(port); + + if (port->type == PORT_SCIFA || port->type == PORT_SCIFB) + ctrl &= ~SCSCR_RDRQE; + + serial_port_out(port, SCSCR, ctrl); +} + +static void sci_stop_rx(struct uart_port *port) +{ + unsigned short ctrl; + + ctrl = serial_port_in(port, SCSCR); + + if (port->type == PORT_SCIFA || port->type == PORT_SCIFB) + ctrl &= ~SCSCR_RDRQE; + + ctrl &= ~port_rx_irq_mask(port); + + serial_port_out(port, SCSCR, ctrl); +} + +static void sci_break_ctl(struct uart_port *port, int break_state) +{ + struct sci_port *s = to_sci_port(port); + struct plat_sci_reg *reg = sci_regmap[s->cfg->regtype] + SCSPTR; + unsigned short scscr, scsptr; + + /* check wheter the port has SCSPTR */ + if (!reg->size) { + /* + * Not supported by hardware. Most parts couple break and rx + * interrupts together, with break detection always enabled. + */ + return; + } + + scsptr = serial_port_in(port, SCSPTR); + scscr = serial_port_in(port, SCSCR); + + if (break_state == -1) { + scsptr = (scsptr | SCSPTR_SPB2IO) & ~SCSPTR_SPB2DT; + scscr &= ~SCSCR_TE; + } else { + scsptr = (scsptr | SCSPTR_SPB2DT) & ~SCSPTR_SPB2IO; + scscr |= SCSCR_TE; + } + + serial_port_out(port, SCSPTR, scsptr); + serial_port_out(port, SCSCR, scscr); +} + +#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->shdma_slave.slave_id); + + chan->private = ¶m->shdma_slave; + return true; +} + +static void rx_timer_fn(unsigned long arg) +{ + struct sci_port *s = (struct sci_port *)arg; + struct uart_port *port = &s->port; + u16 scr = serial_port_in(port, SCSCR); + + if (port->type == PORT_SCIFA || port->type == PORT_SCIFB) { + scr &= ~SCSCR_RDRQE; + enable_irq(s->irqs[SCIx_RXI_IRQ]); + } + serial_port_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\n", __func__, port->line); + + if (s->cfg->dma_slave_tx <= 0 || s->cfg->dma_slave_rx <= 0) + return; + + dma_cap_zero(mask); + dma_cap_set(DMA_SLAVE, mask); + + param = &s->param_tx; + + /* Slave ID, e.g., SHDMA_SLAVE_SCIF0_TX */ + param->shdma_slave.slave_id = s->cfg->dma_slave_tx; + + 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((uintptr_t)port->state->xmit.buf & ~PAGE_MASK); + sg_set_page(&s->sg_tx, virt_to_page(port->state->xmit.buf), + UART_XMIT_SIZE, + (uintptr_t)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 %pad\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->shdma_slave.slave_id = s->cfg->dma_slave_rx; + + 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, + (uintptr_t)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->chan_tx) + sci_tx_dma_release(s, false); + if (s->chan_rx) + sci_rx_dma_release(s, false); +} +#else +static inline void sci_request_dma(struct uart_port *port) +{ +} + +static inline void sci_free_dma(struct uart_port *port) +{ +} +#endif + +static int sci_startup(struct uart_port *port) +{ + struct sci_port *s = to_sci_port(port); + unsigned long flags; + int ret; + + dev_dbg(port->dev, "%s(%d)\n", __func__, port->line); + + ret = sci_request_irq(s); + if (unlikely(ret < 0)) + return ret; + + sci_request_dma(port); + + spin_lock_irqsave(&port->lock, flags); + sci_start_tx(port); + sci_start_rx(port); + spin_unlock_irqrestore(&port->lock, flags); + + return 0; +} + +static void sci_shutdown(struct uart_port *port) +{ + struct sci_port *s = to_sci_port(port); + unsigned long flags; + + dev_dbg(port->dev, "%s(%d)\n", __func__, port->line); + + spin_lock_irqsave(&port->lock, flags); + sci_stop_rx(port); + sci_stop_tx(port); + spin_unlock_irqrestore(&port->lock, flags); + + sci_free_dma(port); + sci_free_irq(s); +} + +static unsigned int sci_scbrr_calc(struct sci_port *s, unsigned int bps, + unsigned long freq) +{ + if (s->sampling_rate) + return DIV_ROUND_CLOSEST(freq, s->sampling_rate * bps) - 1; + + /* Warn, but use a safe default */ + WARN_ON(1); + + return ((freq + 16 * bps) / (32 * bps) - 1); +} + +/* calculate frame length from SMR */ +static int sci_baud_calc_frame_len(unsigned int smr_val) +{ + int len = 10; + + if (smr_val & SCSMR_CHR) + len--; + if (smr_val & SCSMR_PE) + len++; + if (smr_val & SCSMR_STOP) + len++; + + return len; +} + + +/* calculate sample rate, BRR, and clock select for HSCIF */ +static void sci_baud_calc_hscif(unsigned int bps, unsigned long freq, + int *brr, unsigned int *srr, + unsigned int *cks, int frame_len) +{ + int sr, c, br, err, recv_margin; + int min_err = 1000; /* 100% */ + int recv_max_margin = 0; + + /* Find the combination of sample rate and clock select with the + smallest deviation from the desired baud rate. */ + for (sr = 8; sr <= 32; sr++) { + for (c = 0; c <= 3; c++) { + /* integerized formulas from HSCIF documentation */ + br = DIV_ROUND_CLOSEST(freq, (sr * + (1 << (2 * c + 1)) * bps)) - 1; + br = clamp(br, 0, 255); + err = DIV_ROUND_CLOSEST(freq, ((br + 1) * bps * sr * + (1 << (2 * c + 1)) / 1000)) - + 1000; + /* Calc recv margin + * M: Receive margin (%) + * N: Ratio of bit rate to clock (N = sampling rate) + * D: Clock duty (D = 0 to 1.0) + * L: Frame length (L = 9 to 12) + * F: Absolute value of clock frequency deviation + * + * M = |(0.5 - 1 / 2 * N) - ((L - 0.5) * F) - + * (|D - 0.5| / N * (1 + F))| + * NOTE: Usually, treat D for 0.5, F is 0 by this + * calculation. + */ + recv_margin = abs((500 - + DIV_ROUND_CLOSEST(1000, sr << 1)) / 10); + if (abs(min_err) > abs(err)) { + min_err = err; + recv_max_margin = recv_margin; + } else if ((min_err == err) && + (recv_margin > recv_max_margin)) + recv_max_margin = recv_margin; + else + continue; + + *brr = br; + *srr = sr - 1; + *cks = c; + } + } + + if (min_err == 1000) { + WARN_ON(1); + /* use defaults */ + *brr = 255; + *srr = 15; + *cks = 0; + } +} + +static void sci_reset(struct uart_port *port) +{ + struct plat_sci_reg *reg; + unsigned int status; + + do { + status = serial_port_in(port, SCxSR); + } while (!(status & SCxSR_TEND(port))); + + serial_port_out(port, SCSCR, 0x00); /* TE=0, RE=0, CKE1=0 */ + + reg = sci_getreg(port, SCFCR); + if (reg->size) + serial_port_out(port, SCFCR, SCFCR_RFRST | SCFCR_TFRST); +} + +static void sci_set_termios(struct uart_port *port, struct ktermios *termios, + struct ktermios *old) +{ + struct sci_port *s = to_sci_port(port); + struct plat_sci_reg *reg; + unsigned int baud, smr_val = 0, max_baud, cks = 0; + int t = -1; + unsigned int srr = 15; + + if ((termios->c_cflag & CSIZE) == CS7) + smr_val |= SCSMR_CHR; + if (termios->c_cflag & PARENB) + smr_val |= SCSMR_PE; + if (termios->c_cflag & PARODD) + smr_val |= SCSMR_PE | SCSMR_ODD; + if (termios->c_cflag & CSTOPB) + smr_val |= SCSMR_STOP; + + /* + * 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)) { + if (s->cfg->type == PORT_HSCIF) { + int frame_len = sci_baud_calc_frame_len(smr_val); + sci_baud_calc_hscif(baud, port->uartclk, &t, &srr, + &cks, frame_len); + } else { + t = sci_scbrr_calc(s, baud, port->uartclk); + for (cks = 0; t >= 256 && cks <= 3; cks++) + t >>= 2; + } + } + + sci_port_enable(s); + + sci_reset(port); + + smr_val |= serial_port_in(port, SCSMR) & 3; + + uart_update_timeout(port, termios->c_cflag, baud); + + dev_dbg(port->dev, "%s: SMR %x, cks %x, t %x, SCSCR %x\n", + __func__, smr_val, cks, t, s->cfg->scscr); + + if (t >= 0) { + serial_port_out(port, SCSMR, (smr_val & ~SCSMR_CKS) | cks); + serial_port_out(port, SCBRR, t); + reg = sci_getreg(port, HSSRR); + if (reg->size) + serial_port_out(port, HSSRR, srr | HSCIF_SRE); + udelay((1000000+(baud-1)) / baud); /* Wait one bit interval */ + } else + serial_port_out(port, SCSMR, smr_val); + + sci_init_pins(port, termios->c_cflag); + + reg = sci_getreg(port, SCFCR); + if (reg->size) { + unsigned short ctrl = serial_port_in(port, SCFCR); + + if (s->cfg->capabilities & SCIx_HAVE_RTSCTS) { + if (termios->c_cflag & CRTSCTS) + ctrl |= SCFCR_MCE; + else + ctrl &= ~SCFCR_MCE; + } + + /* + * As we've done a sci_reset() above, ensure we don't + * interfere with the FIFOs while toggling MCE. As the + * reset values could still be set, simply mask them out. + */ + ctrl &= ~(SCFCR_RFRST | SCFCR_TFRST); + + serial_port_out(port, SCFCR, ctrl); + } + + serial_port_out(port, SCSCR, s->cfg->scscr); + +#ifdef CONFIG_SERIAL_SH_SCI_DMA + /* + * Calculate delay for 2 DMA buffers (4 FIFO). + * 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 5 jiffies (20ms) for 2 DMA buffers (4 FIFO + * sizes), but when performing a faster transfer, value obtained by + * this formula is may not enough. Therefore, if value is smaller than + * 20msec, this sets 20msec as timeout of DMA. + */ + if (s->chan_rx) { + unsigned int bits; + + /* byte size and parity */ + switch (termios->c_cflag & CSIZE) { + case CS5: + bits = 7; + break; + case CS6: + bits = 8; + break; + case CS7: + bits = 9; + break; + default: + bits = 10; + break; + } + + if (termios->c_cflag & CSTOPB) + bits++; + if (termios->c_cflag & PARENB) + bits++; + s->rx_timeout = DIV_ROUND_UP((s->buf_len_rx * 2 * bits * HZ) / + (baud / 10), 10); + 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); + + sci_port_disable(s); +} + +static void sci_pm(struct uart_port *port, unsigned int state, + unsigned int oldstate) +{ + struct sci_port *sci_port = to_sci_port(port); + + switch (state) { + case UART_PM_STATE_OFF: + sci_port_disable(sci_port); + break; + default: + sci_port_enable(sci_port); + break; + } +} + +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"; + case PORT_HSCIF: + return "hscif"; + } + + return NULL; +} + +static inline unsigned long sci_port_size(struct uart_port *port) +{ + /* + * Pick an arbitrary size that encapsulates all of the base + * registers by default. This can be optimized later, or derived + * from platform resource data at such a time that ports begin to + * behave more erratically. + */ + if (port->type == PORT_HSCIF) + return 96; + else + return 64; +} + +static int sci_remap_port(struct uart_port *port) +{ + unsigned long size = sci_port_size(port); + + /* + * Nothing to do if there's already an established membase. + */ + if (port->membase) + return 0; + + if (port->flags & UPF_IOREMAP) { + port->membase = ioremap_nocache(port->mapbase, size); + if (unlikely(!port->membase)) { + dev_err(port->dev, "can't remap port#%d\n", port->line); + return -ENXIO; + } + } 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 *)(uintptr_t)port->mapbase; + } + + return 0; +} + +static void sci_release_port(struct uart_port *port) +{ + if (port->flags & UPF_IOREMAP) { + iounmap(port->membase); + port->membase = NULL; + } + + release_mem_region(port->mapbase, sci_port_size(port)); +} + +static int sci_request_port(struct uart_port *port) +{ + unsigned long size = sci_port_size(port); + struct resource *res; + int ret; + + res = request_mem_region(port->mapbase, size, dev_name(port->dev)); + if (unlikely(res == NULL)) + return -EBUSY; + + ret = sci_remap_port(port); + if (unlikely(ret != 0)) { + release_resource(res); + return ret; + } + + return 0; +} + +static void sci_config_port(struct uart_port *port, int flags) +{ + if (flags & UART_CONFIG_TYPE) { + struct sci_port *sport = to_sci_port(port); + + port->type = sport->cfg->type; + sci_request_port(port); + } +} + +static int sci_verify_port(struct uart_port *port, struct serial_struct *ser) +{ + 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, + .break_ctl = sci_break_ctl, + .startup = sci_startup, + .shutdown = sci_shutdown, + .set_termios = sci_set_termios, + .pm = sci_pm, + .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 sci_init_single(struct platform_device *dev, + struct sci_port *sci_port, unsigned int index, + struct plat_sci_port *p, bool early) +{ + struct uart_port *port = &sci_port->port; + const struct resource *res; + unsigned int sampling_rate; + unsigned int i; + int ret; + + sci_port->cfg = p; + + port->ops = &sci_uart_ops; + port->iotype = UPIO_MEM; + port->line = index; + + res = platform_get_resource(dev, IORESOURCE_MEM, 0); + if (res == NULL) + return -ENOMEM; + + port->mapbase = res->start; + + for (i = 0; i < ARRAY_SIZE(sci_port->irqs); ++i) + sci_port->irqs[i] = platform_get_irq(dev, i); + + /* The SCI generates several interrupts. They can be muxed together or + * connected to different interrupt lines. In the muxed case only one + * interrupt resource is specified. In the non-muxed case three or four + * interrupt resources are specified, as the BRI interrupt is optional. + */ + if (sci_port->irqs[0] < 0) + return -ENXIO; + + if (sci_port->irqs[1] < 0) { + sci_port->irqs[1] = sci_port->irqs[0]; + sci_port->irqs[2] = sci_port->irqs[0]; + sci_port->irqs[3] = sci_port->irqs[0]; + } + + if (p->regtype == SCIx_PROBE_REGTYPE) { + ret = sci_probe_regmap(p); + if (unlikely(ret)) + return ret; + } + + switch (p->type) { + case PORT_SCIFB: + port->fifosize = 256; + sci_port->overrun_bit = 9; + sampling_rate = 16; + break; + case PORT_HSCIF: + port->fifosize = 128; + sampling_rate = 0; + sci_port->overrun_bit = 0; + break; + case PORT_SCIFA: + port->fifosize = 64; + sci_port->overrun_bit = 9; + sampling_rate = 16; + break; + case PORT_SCIF: + port->fifosize = 16; + if (p->regtype == SCIx_SH7705_SCIF_REGTYPE) { + sci_port->overrun_bit = 9; + sampling_rate = 16; + } else { + sci_port->overrun_bit = 0; + sampling_rate = 32; + } + break; + default: + port->fifosize = 1; + sci_port->overrun_bit = 5; + sampling_rate = 32; + break; + } + + /* SCIFA on sh7723 and sh7724 need a custom sampling rate that doesn't + * match the SoC datasheet, this should be investigated. Let platform + * data override the sampling rate for now. + */ + sci_port->sampling_rate = p->sampling_rate ? p->sampling_rate + : sampling_rate; + + if (!early) { + 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; + + port->dev = &dev->dev; + + pm_runtime_enable(&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); + + /* + * Establish some sensible defaults for the error detection. + */ + sci_port->error_mask = (p->type == PORT_SCI) ? + SCI_DEFAULT_ERROR_MASK : SCIF_DEFAULT_ERROR_MASK; + + /* + * Establish sensible defaults for the overrun detection, unless + * the part has explicitly disabled support for it. + */ + + /* + * Make the error mask inclusive of overrun detection, if + * supported. + */ + sci_port->error_mask |= 1 << sci_port->overrun_bit; + + port->type = p->type; + port->flags = UPF_FIXED_PORT | p->flags; + port->regshift = p->regshift; + + /* + * The UART port needs an IRQ value, so we peg this to the RX IRQ + * for the multi-IRQ ports, which is where we are primarily + * concerned with the shutdown path synchronization. + * + * For the muxed case there's nothing more to do. + */ + port->irq = sci_port->irqs[SCIx_RXI_IRQ]; + port->irqflags = 0; + + port->serial_in = sci_serial_in; + port->serial_out = sci_serial_out; + + if (p->dma_slave_tx > 0 && p->dma_slave_rx > 0) + dev_dbg(port->dev, "DMA tx %d, rx %d\n", + p->dma_slave_tx, p->dma_slave_rx); + + return 0; +} + +static void sci_cleanup_single(struct sci_port *port) +{ + clk_put(port->iclk); + clk_put(port->fclk); + + pm_runtime_disable(port->port.dev); +} + +#ifdef CONFIG_SERIAL_SH_SCI_CONSOLE +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 sci_port *sci_port = &sci_ports[co->index]; + struct uart_port *port = &sci_port->port; + unsigned short bits, ctrl; + unsigned long flags; + int locked = 1; + + local_irq_save(flags); + if (port->sysrq) + locked = 0; + else if (oops_in_progress) + locked = spin_trylock(&port->lock); + else + spin_lock(&port->lock); + + /* first save the SCSCR then disable the interrupts */ + ctrl = serial_port_in(port, SCSCR); + serial_port_out(port, SCSCR, sci_port->cfg->scscr); + + 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 ((serial_port_in(port, SCxSR) & bits) != bits) + cpu_relax(); + + /* restore the SCSCR */ + serial_port_out(port, SCSCR, ctrl); + + if (locked) + spin_unlock(&port->lock); + local_irq_restore(flags); +} + +static int 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; + + /* + * Refuse to handle any bogus ports. + */ + if (co->index < 0 || co->index >= SCI_NPORTS) + return -ENODEV; + + sci_port = &sci_ports[co->index]; + port = &sci_port->port; + + /* + * Refuse to handle uninitialized ports. + */ + if (!port->ops) + return -ENODEV; + + ret = sci_remap_port(port); + if (unlikely(ret != 0)) + return ret; + + if (options) + uart_parse_options(options, &baud, &parity, &bits, &flow); + + return uart_set_options(port, co, baud, parity, bits, flow); +} + +static struct console serial_console = { + .name = "ttySC", + .device = uart_console_device, + .write = serial_console_write, + .setup = serial_console_setup, + .flags = CON_PRINTBUFFER, + .index = -1, + .data = &sci_uart_driver, +}; + +static struct console early_serial_console = { + .name = "early_ttySC", + .write = serial_console_write, + .flags = CON_PRINTBUFFER, + .index = -1, +}; + +static char early_serial_buf[32]; + +static int sci_probe_earlyprintk(struct platform_device *pdev) +{ + struct plat_sci_port *cfg = dev_get_platdata(&pdev->dev); + + if (early_serial_console.data) + return -EEXIST; + + early_serial_console.index = pdev->id; + + sci_init_single(pdev, &sci_ports[pdev->id], pdev->id, cfg, true); + + 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; +} + +#define SCI_CONSOLE (&serial_console) + +#else +static inline int sci_probe_earlyprintk(struct platform_device *pdev) +{ + return -EINVAL; +} + +#define SCI_CONSOLE NULL + +#endif /* CONFIG_SERIAL_SH_SCI_CONSOLE */ + +static const char banner[] __initconst = "SuperH (H)SCI(F) driver initialized"; + +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 sci_port *port = platform_get_drvdata(dev); + + cpufreq_unregister_notifier(&port->freq_transition, + CPUFREQ_TRANSITION_NOTIFIER); + + uart_remove_one_port(&sci_uart_driver, &port->port); + + sci_cleanup_single(port); + + return 0; +} + +struct sci_port_info { + unsigned int type; + unsigned int regtype; +}; + +static const struct of_device_id of_sci_match[] = { + { + .compatible = "renesas,scif", + .data = &(const struct sci_port_info) { + .type = PORT_SCIF, + .regtype = SCIx_SH4_SCIF_REGTYPE, + }, + }, { + .compatible = "renesas,scifa", + .data = &(const struct sci_port_info) { + .type = PORT_SCIFA, + .regtype = SCIx_SCIFA_REGTYPE, + }, + }, { + .compatible = "renesas,scifb", + .data = &(const struct sci_port_info) { + .type = PORT_SCIFB, + .regtype = SCIx_SCIFB_REGTYPE, + }, + }, { + .compatible = "renesas,hscif", + .data = &(const struct sci_port_info) { + .type = PORT_HSCIF, + .regtype = SCIx_HSCIF_REGTYPE, + }, + }, { + /* Terminator */ + }, +}; +MODULE_DEVICE_TABLE(of, of_sci_match); + +static struct plat_sci_port * +sci_parse_dt(struct platform_device *pdev, unsigned int *dev_id) +{ + struct device_node *np = pdev->dev.of_node; + const struct of_device_id *match; + const struct sci_port_info *info; + struct plat_sci_port *p; + int id; + + if (!IS_ENABLED(CONFIG_OF) || !np) + return NULL; + + match = of_match_node(of_sci_match, pdev->dev.of_node); + if (!match) + return NULL; + + info = match->data; + + p = devm_kzalloc(&pdev->dev, sizeof(struct plat_sci_port), GFP_KERNEL); + if (!p) { + dev_err(&pdev->dev, "failed to allocate DT config data\n"); + return NULL; + } + + /* Get the line number for the aliases node. */ + id = of_alias_get_id(np, "serial"); + if (id < 0) { + dev_err(&pdev->dev, "failed to get alias id (%d)\n", id); + return NULL; + } + + *dev_id = id; + + p->flags = UPF_IOREMAP | UPF_BOOT_AUTOCONF; + p->type = info->type; + p->regtype = info->regtype; + p->scscr = SCSCR_RE | SCSCR_TE; + + return p; +} + +static int sci_probe_single(struct platform_device *dev, + unsigned int index, + struct plat_sci_port *p, + struct sci_port *sciport) +{ + 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 -EINVAL; + } + + ret = sci_init_single(dev, sciport, index, p, false); + if (ret) + return ret; + + ret = uart_add_one_port(&sci_uart_driver, &sciport->port); + if (ret) { + sci_cleanup_single(sciport); + return ret; + } + + return 0; +} + +static int sci_probe(struct platform_device *dev) +{ + struct plat_sci_port *p; + struct sci_port *sp; + unsigned int dev_id; + int ret; + + /* + * If we've come here via earlyprintk initialization, head off to + * the special early probe. We don't have sufficient device state + * to make it beyond this yet. + */ + if (is_early_platform_device(dev)) + return sci_probe_earlyprintk(dev); + + if (dev->dev.of_node) { + p = sci_parse_dt(dev, &dev_id); + if (p == NULL) + return -EINVAL; + } else { + p = dev->dev.platform_data; + if (p == NULL) { + dev_err(&dev->dev, "no platform data supplied\n"); + return -EINVAL; + } + + dev_id = dev->id; + } + + sp = &sci_ports[dev_id]; + platform_set_drvdata(dev, sp); + + ret = sci_probe_single(dev, dev_id, p, sp); + if (ret) + return ret; + + sp->freq_transition.notifier_call = sci_notifier; + + ret = cpufreq_register_notifier(&sp->freq_transition, + CPUFREQ_TRANSITION_NOTIFIER); + if (unlikely(ret < 0)) { + uart_remove_one_port(&sci_uart_driver, &sp->port); + sci_cleanup_single(sp); + return ret; + } + +#ifdef CONFIG_SH_STANDARD_BIOS + sh_bios_gdb_detach(); +#endif + + return 0; +} + +static __maybe_unused int sci_suspend(struct device *dev) +{ + struct sci_port *sport = dev_get_drvdata(dev); + + if (sport) + uart_suspend_port(&sci_uart_driver, &sport->port); + + return 0; +} + +static __maybe_unused int sci_resume(struct device *dev) +{ + struct sci_port *sport = dev_get_drvdata(dev); + + if (sport) + uart_resume_port(&sci_uart_driver, &sport->port); + + return 0; +} + +static SIMPLE_DEV_PM_OPS(sci_dev_pm_ops, sci_suspend, sci_resume); + +static struct platform_driver sci_driver = { + .probe = sci_probe, + .remove = sci_remove, + .driver = { + .name = "sh-sci", + .pm = &sci_dev_pm_ops, + .of_match_table = of_match_ptr(of_sci_match), + }, +}; + +static int __init sci_init(void) +{ + int ret; + + pr_info("%s\n", 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"); +MODULE_AUTHOR("Paul Mundt"); +MODULE_DESCRIPTION("SuperH (H)SCI(F) serial driver"); |