| /* |
| * 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; |
| |
| reg = sci_getreg(port, SCLSR); |
| if (!reg->size) |
| return 0; |
| |
| if ((serial_port_in(port, SCLSR) & (1 << s->overrun_bit))) { |
| serial_port_out(port, SCLSR, 0); |
| |
| port->icount.overrun++; |
| |
| tty_insert_flip_char(tport, 0, TTY_OVERRUN); |
| tty_flip_buffer_push(tport); |
| |
| dev_notice(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; |
| 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); |
| 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 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; |
| if (err < 0) |
| continue; |
| |
| /* 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 (min_err > 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 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); |
| |
| 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 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 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 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, |
| .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"); |