diff options
author | Paul Mundt <lethal@linux-sh.org> | 2011-01-13 15:06:28 +0900 |
---|---|---|
committer | Paul Mundt <lethal@linux-sh.org> | 2011-01-13 15:06:28 +0900 |
commit | f43dc23d5ea91fca257be02138a255f02d98e806 (patch) | |
tree | b29722f6e965316e90ac97abf79923ced250dc21 /drivers/serial/sh-sci.c | |
parent | f8e53553f452dcbf67cb89c8cba63a1cd6eb4cc0 (diff) | |
parent | 4162cf64973df51fc885825bc9ca4d055891c49f (diff) |
Merge branch 'master' of master.kernel.org:/pub/scm/linux/kernel/git/torvalds/linux-2.6 into common/serial-rework
Conflicts:
arch/sh/kernel/cpu/sh2/setup-sh7619.c
arch/sh/kernel/cpu/sh2a/setup-mxg.c
arch/sh/kernel/cpu/sh2a/setup-sh7201.c
arch/sh/kernel/cpu/sh2a/setup-sh7203.c
arch/sh/kernel/cpu/sh2a/setup-sh7206.c
arch/sh/kernel/cpu/sh3/setup-sh7705.c
arch/sh/kernel/cpu/sh3/setup-sh770x.c
arch/sh/kernel/cpu/sh3/setup-sh7710.c
arch/sh/kernel/cpu/sh3/setup-sh7720.c
arch/sh/kernel/cpu/sh4/setup-sh4-202.c
arch/sh/kernel/cpu/sh4/setup-sh7750.c
arch/sh/kernel/cpu/sh4/setup-sh7760.c
arch/sh/kernel/cpu/sh4a/setup-sh7343.c
arch/sh/kernel/cpu/sh4a/setup-sh7366.c
arch/sh/kernel/cpu/sh4a/setup-sh7722.c
arch/sh/kernel/cpu/sh4a/setup-sh7723.c
arch/sh/kernel/cpu/sh4a/setup-sh7724.c
arch/sh/kernel/cpu/sh4a/setup-sh7763.c
arch/sh/kernel/cpu/sh4a/setup-sh7770.c
arch/sh/kernel/cpu/sh4a/setup-sh7780.c
arch/sh/kernel/cpu/sh4a/setup-sh7785.c
arch/sh/kernel/cpu/sh4a/setup-sh7786.c
arch/sh/kernel/cpu/sh4a/setup-shx3.c
arch/sh/kernel/cpu/sh5/setup-sh5.c
drivers/serial/sh-sci.c
drivers/serial/sh-sci.h
include/linux/serial_sci.h
Diffstat (limited to 'drivers/serial/sh-sci.c')
-rw-r--r-- | drivers/serial/sh-sci.c | 947 |
1 files changed, 797 insertions, 150 deletions
diff --git a/drivers/serial/sh-sci.c b/drivers/serial/sh-sci.c index 403b01b382e..251c08c55ae 100644 --- a/drivers/serial/sh-sci.c +++ b/drivers/serial/sh-sci.c @@ -3,7 +3,7 @@ * * SuperH on-chip serial module support. (SCI with no FIFO / with FIFO) * - * Copyright (C) 2002 - 2008 Paul Mundt + * 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: @@ -48,9 +48,11 @@ #include <linux/ctype.h> #include <linux/err.h> #include <linux/list.h> +#include <linux/dmaengine.h> +#include <linux/scatterlist.h> +#include <linux/slab.h> #ifdef CONFIG_SUPERH -#include <asm/clock.h> #include <asm/sh_bios.h> #endif @@ -85,22 +87,42 @@ struct sci_port { /* SCBRR calculation algo */ unsigned int scbrr_algo_id; -#ifdef CONFIG_HAVE_CLK /* Interface clock */ struct clk *iclk; - /* Data clock */ - struct clk *dclk; -#endif + /* Function clock */ + struct clk *fclk; + struct list_head node; + + struct dma_chan *chan_tx; + struct dma_chan *chan_rx; + +#ifdef CONFIG_SERIAL_SH_SCI_DMA + struct device *dma_dev; + unsigned int slave_tx; + unsigned int slave_rx; + struct dma_async_tx_descriptor *desc_tx; + struct dma_async_tx_descriptor *desc_rx[2]; + dma_cookie_t cookie_tx; + dma_cookie_t cookie_rx[2]; + dma_cookie_t active_rx; + struct scatterlist sg_tx; + unsigned int sg_len_tx; + struct scatterlist sg_rx[2]; + size_t buf_len_rx; + struct sh_dmae_slave param_tx; + struct sh_dmae_slave param_rx; + struct work_struct work_tx; + struct work_struct work_rx; + struct timer_list rx_timer; + unsigned int rx_timeout; +#endif }; struct sh_sci_priv { spinlock_t lock; struct list_head ports; - -#ifdef CONFIG_HAVE_CLK struct notifier_block clk_nb; -#endif }; /* Function prototypes */ @@ -137,7 +159,11 @@ static int sci_poll_get_char(struct uart_port *port) handle_error(port); continue; } - } while (!(status & SCxSR_RDxF(port))); + break; + } while (1); + + if (!(status & SCxSR_RDxF(port))) + return NO_POLL_CHAR; c = sci_in(port, SCxRDR); @@ -162,32 +188,6 @@ static void sci_poll_put_char(struct uart_port *port, unsigned char c) } #endif /* CONFIG_CONSOLE_POLL || CONFIG_SERIAL_SH_SCI_CONSOLE */ -#if defined(__H8300S__) -enum { sci_disable, sci_enable }; - -static void h8300_sci_config(struct uart_port *port, unsigned int ctrl) -{ - volatile unsigned char *mstpcrl = (volatile unsigned char *)MSTPCRL; - int ch = (port->mapbase - SMR0) >> 3; - unsigned char mask = 1 << (ch+1); - - if (ctrl == sci_disable) - *mstpcrl |= mask; - else - *mstpcrl &= ~mask; -} - -static void h8300_sci_enable(struct uart_port *port) -{ - h8300_sci_config(port, sci_enable); -} - -static void h8300_sci_disable(struct uart_port *port) -{ - h8300_sci_config(port, sci_disable); -} -#endif - #if defined(__H8300H__) || defined(__H8300S__) static void sci_init_pins(struct uart_port *port, unsigned int cflag) { @@ -259,9 +259,9 @@ static inline void sci_init_pins(struct uart_port *port, unsigned int cflag) Set SCP6MD1,0 = {01} (output) */ __raw_writew((data & 0x0fcf) | 0x1000, SCPCR); - data = ctrl_inb(SCPDR); + data = __raw_readb(SCPDR); /* Set /RTS2 (bit6) = 0 */ - ctrl_outb(data & 0xbf, SCPDR); + __raw_writeb(data & 0xbf, SCPDR); } } #elif defined(CONFIG_CPU_SUBTYPE_SH7722) @@ -278,7 +278,8 @@ static inline void sci_init_pins(struct uart_port *port, unsigned int cflag) __raw_writew(data, PSCR); } } -#elif defined(CONFIG_CPU_SUBTYPE_SH7763) || \ +#elif defined(CONFIG_CPU_SUBTYPE_SH7757) || \ + defined(CONFIG_CPU_SUBTYPE_SH7763) || \ defined(CONFIG_CPU_SUBTYPE_SH7780) || \ defined(CONFIG_CPU_SUBTYPE_SH7785) || \ defined(CONFIG_CPU_SUBTYPE_SH7786) || \ @@ -305,29 +306,44 @@ static inline void sci_init_pins(struct uart_port *port, unsigned int cflag) defined(CONFIG_CPU_SUBTYPE_SH7780) || \ defined(CONFIG_CPU_SUBTYPE_SH7785) || \ defined(CONFIG_CPU_SUBTYPE_SH7786) -static inline int scif_txroom(struct uart_port *port) +static int scif_txfill(struct uart_port *port) +{ + return sci_in(port, SCTFDR) & 0xff; +} + +static int scif_txroom(struct uart_port *port) { - return SCIF_TXROOM_MAX - (sci_in(port, SCTFDR) & 0xff); + return SCIF_TXROOM_MAX - scif_txfill(port); } -static inline int scif_rxroom(struct uart_port *port) +static int scif_rxfill(struct uart_port *port) { return sci_in(port, SCRFDR) & 0xff; } #elif defined(CONFIG_CPU_SUBTYPE_SH7763) -static inline int scif_txroom(struct uart_port *port) +static int scif_txfill(struct uart_port *port) { - if ((port->mapbase == 0xffe00000) || - (port->mapbase == 0xffe08000)) { + if (port->mapbase == 0xffe00000 || + port->mapbase == 0xffe08000) /* SCIF0/1*/ - return SCIF_TXROOM_MAX - (sci_in(port, SCTFDR) & 0xff); - } else { + return sci_in(port, SCTFDR) & 0xff; + else /* SCIF2 */ - return SCIF2_TXROOM_MAX - (sci_in(port, SCFDR) >> 8); - } + return sci_in(port, SCFDR) >> 8; } -static inline int scif_rxroom(struct uart_port *port) +static int scif_txroom(struct uart_port *port) +{ + if (port->mapbase == 0xffe00000 || + port->mapbase == 0xffe08000) + /* SCIF0/1*/ + return SCIF_TXROOM_MAX - scif_txfill(port); + else + /* SCIF2 */ + return SCIF2_TXROOM_MAX - scif_txfill(port); +} + +static int scif_rxfill(struct uart_port *port) { if ((port->mapbase == 0xffe00000) || (port->mapbase == 0xffe08000)) { @@ -338,24 +354,55 @@ static inline int scif_rxroom(struct uart_port *port) return sci_in(port, SCFDR) & SCIF2_RFDC_MASK; } } +#elif defined(CONFIG_ARCH_SH7372) +static int scif_txfill(struct uart_port *port) +{ + if (port->type == PORT_SCIFA) + return sci_in(port, SCFDR) >> 8; + else + return sci_in(port, SCTFDR); +} + +static int scif_txroom(struct uart_port *port) +{ + return port->fifosize - scif_txfill(port); +} + +static int scif_rxfill(struct uart_port *port) +{ + if (port->type == PORT_SCIFA) + return sci_in(port, SCFDR) & SCIF_RFDC_MASK; + else + return sci_in(port, SCRFDR); +} #else -static inline int scif_txroom(struct uart_port *port) +static int scif_txfill(struct uart_port *port) +{ + return sci_in(port, SCFDR) >> 8; +} + +static int scif_txroom(struct uart_port *port) { - return SCIF_TXROOM_MAX - (sci_in(port, SCFDR) >> 8); + return SCIF_TXROOM_MAX - scif_txfill(port); } -static inline int scif_rxroom(struct uart_port *port) +static int scif_rxfill(struct uart_port *port) { return sci_in(port, SCFDR) & SCIF_RFDC_MASK; } #endif -static inline int sci_txroom(struct uart_port *port) +static int sci_txfill(struct uart_port *port) { - return (sci_in(port, SCxSR) & SCI_TDRE) != 0; + return !(sci_in(port, SCxSR) & SCI_TDRE); } -static inline int sci_rxroom(struct uart_port *port) +static int sci_txroom(struct uart_port *port) +{ + return !sci_txfill(port); +} + +static int sci_rxfill(struct uart_port *port) { return (sci_in(port, SCxSR) & SCxSR_RDxF(port)) != 0; } @@ -366,7 +413,7 @@ static inline int sci_rxroom(struct uart_port *port) static void sci_transmit_chars(struct uart_port *port) { - struct circ_buf *xmit = &port->info->xmit; + struct circ_buf *xmit = &port->state->xmit; unsigned int stopped = uart_tx_stopped(port); unsigned short status; unsigned short ctrl; @@ -431,7 +478,7 @@ static void sci_transmit_chars(struct uart_port *port) static inline void sci_receive_chars(struct uart_port *port) { struct sci_port *sci_port = to_sci_port(port); - struct tty_struct *tty = port->info->port.tty; + struct tty_struct *tty = port->state->port.tty; int i, count, copied = 0; unsigned short status; unsigned char flag; @@ -442,9 +489,9 @@ static inline void sci_receive_chars(struct uart_port *port) while (1) { if (port->type == PORT_SCI) - count = sci_rxroom(port); + count = sci_rxfill(port); else - count = scif_rxroom(port); + count = scif_rxfill(port); /* Don't copy more bytes than there is room for in the buffer */ count = tty_buffer_request_room(tty, count); @@ -489,10 +536,10 @@ static inline void sci_receive_chars(struct uart_port *port) } /* Store data and status */ - if (status&SCxSR_FER(port)) { + if (status & SCxSR_FER(port)) { flag = TTY_FRAME; dev_notice(port->dev, "frame error\n"); - } else if (status&SCxSR_PER(port)) { + } else if (status & SCxSR_PER(port)) { flag = TTY_PARITY; dev_notice(port->dev, "parity error\n"); } else @@ -551,7 +598,7 @@ static inline int sci_handle_errors(struct uart_port *port) { int copied = 0; unsigned short status = sci_in(port, SCxSR); - struct tty_struct *tty = port->info->port.tty; + struct tty_struct *tty = port->state->port.tty; if (status & SCxSR_ORER(port)) { /* overrun error */ @@ -605,7 +652,7 @@ static inline int sci_handle_errors(struct uart_port *port) static inline int sci_handle_fifo_overrun(struct uart_port *port) { - struct tty_struct *tty = port->info->port.tty; + struct tty_struct *tty = port->state->port.tty; int copied = 0; if (port->type != PORT_SCIF) @@ -628,7 +675,7 @@ static inline int sci_handle_breaks(struct uart_port *port) { int copied = 0; unsigned short status = sci_in(port, SCxSR); - struct tty_struct *tty = port->info->port.tty; + struct tty_struct *tty = port->state->port.tty; struct sci_port *s = to_sci_port(port); if (uart_handle_break(port)) @@ -654,13 +701,39 @@ static inline int sci_handle_breaks(struct uart_port *port) return copied; } -static irqreturn_t sci_rx_interrupt(int irq, void *port) +static irqreturn_t sci_rx_interrupt(int irq, void *ptr) { +#ifdef CONFIG_SERIAL_SH_SCI_DMA + struct uart_port *port = ptr; + struct sci_port *s = to_sci_port(port); + + if (s->chan_rx) { + u16 scr = sci_in(port, SCSCR); + u16 ssr = sci_in(port, SCxSR); + + /* Disable future Rx interrupts */ + if (port->type == PORT_SCIFA || port->type == PORT_SCIFB) { + disable_irq_nosync(irq); + scr |= 0x4000; + } else { + scr &= ~SCSCR_RIE; + } + sci_out(port, SCSCR, scr); + /* Clear current interrupt */ + sci_out(port, SCxSR, ssr & ~(1 | SCxSR_RDxF(port))); + dev_dbg(port->dev, "Rx IRQ %lu: setup t-out in %u jiffies\n", + jiffies, s->rx_timeout); + mod_timer(&s->rx_timer, jiffies + s->rx_timeout); + + return IRQ_HANDLED; + } +#endif + /* I think sci_receive_chars has to be called irrespective * of whether the I_IXOFF is set, otherwise, how is the interrupt * to be disabled? */ - sci_receive_chars(port); + sci_receive_chars(ptr); return IRQ_HANDLED; } @@ -668,10 +741,11 @@ static irqreturn_t sci_rx_interrupt(int irq, void *port) static irqreturn_t sci_tx_interrupt(int irq, void *ptr) { struct uart_port *port = ptr; + unsigned long flags; - spin_lock_irq(&port->lock); + spin_lock_irqsave(&port->lock, flags); sci_transmit_chars(port); - spin_unlock_irq(&port->lock); + spin_unlock_irqrestore(&port->lock, flags); return IRQ_HANDLED; } @@ -711,32 +785,53 @@ static irqreturn_t sci_br_interrupt(int irq, void *ptr) return IRQ_HANDLED; } +static inline unsigned long port_rx_irq_mask(struct uart_port *port) +{ + /* + * Not all ports (such as SCIFA) will support REIE. Rather than + * special-casing the port type, we check the port initialization + * IRQ enable mask to see whether the IRQ is desired at all. If + * it's unset, it's logically inferred that there's no point in + * testing for it. + */ + return SCSCR_RIE | (to_sci_port(port)->scscr & SCSR_REIE); +} + static irqreturn_t sci_mpxed_interrupt(int irq, void *ptr) { - unsigned short ssr_status, scr_status; + unsigned short ssr_status, scr_status, err_enabled; struct uart_port *port = ptr; + struct sci_port *s = to_sci_port(port); irqreturn_t ret = IRQ_NONE; ssr_status = sci_in(port, SCxSR); scr_status = sci_in(port, SCSCR); + err_enabled = scr_status & port_rx_irq_mask(port); /* Tx Interrupt */ - if ((ssr_status & 0x0020) && (scr_status & SCSCR_TIE)) + if ((ssr_status & SCxSR_TDxE(port)) && (scr_status & SCSCR_TIE) && + !s->chan_tx) ret = sci_tx_interrupt(irq, ptr); - /* Rx Interrupt */ - if ((ssr_status & 0x0002) && (scr_status & SCSCR_RIE)) + + /* + * 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 & 0x0080) && (scr_status & SCSCR_REIE)) + if ((ssr_status & SCxSR_ERRORS(port)) && err_enabled) ret = sci_er_interrupt(irq, ptr); + /* Break Interrupt */ - if ((ssr_status & 0x0010) && (scr_status & SCSCR_REIE)) + if ((ssr_status & SCxSR_BRK(port)) && err_enabled) ret = sci_br_interrupt(irq, ptr); return ret; } -#ifdef CONFIG_HAVE_CLK /* * Here we define a transistion notifier so that we can update all of our * ports' baud rate when the peripheral clock changes. @@ -753,8 +848,7 @@ static int sci_notifier(struct notifier_block *self, (phase == CPUFREQ_RESUMECHANGE)) { spin_lock_irqsave(&priv->lock, flags); list_for_each_entry(sci_port, &priv->ports, node) - sci_port->port.uartclk = clk_get_rate(sci_port->dclk); - + sci_port->port.uartclk = clk_get_rate(sci_port->iclk); spin_unlock_irqrestore(&priv->lock, flags); } @@ -765,23 +859,18 @@ static void sci_clk_enable(struct uart_port *port) { struct sci_port *sci_port = to_sci_port(port); - clk_enable(sci_port->dclk); - sci_port->port.uartclk = clk_get_rate(sci_port->dclk); - - if (sci_port->iclk) - clk_enable(sci_port->iclk); + clk_enable(sci_port->iclk); + sci_port->port.uartclk = clk_get_rate(sci_port->iclk); + clk_enable(sci_port->fclk); } static void sci_clk_disable(struct uart_port *port) { struct sci_port *sci_port = to_sci_port(port); - if (sci_port->iclk) - clk_disable(sci_port->iclk); - - clk_disable(sci_port->dclk); + clk_disable(sci_port->fclk); + clk_disable(sci_port->iclk); } -#endif static int sci_request_irq(struct sci_port *port) { @@ -836,8 +925,10 @@ static void sci_free_irq(struct sci_port *port) static unsigned int sci_tx_empty(struct uart_port *port) { - /* Can't detect */ - return TIOCSER_TEMT; + unsigned short status = sci_in(port, SCxSR); + unsigned short in_tx_fifo = scif_txfill(port); + + return (status & SCxSR_TEND(port)) && !in_tx_fifo ? TIOCSER_TEMT : 0; } static void sci_set_mctrl(struct uart_port *port, unsigned int mctrl) @@ -849,20 +940,314 @@ static void sci_set_mctrl(struct uart_port *port, unsigned int mctrl) static unsigned int sci_get_mctrl(struct uart_port *port) { - /* This routine is used for geting signals of: DTR, DCD, DSR, RI, + /* This routine is used for getting signals of: DTR, DCD, DSR, RI, and CTS/RTS */ return TIOCM_DTR | TIOCM_RTS | TIOCM_DSR; } +#ifdef CONFIG_SERIAL_SH_SCI_DMA +static void sci_dma_tx_complete(void *arg) +{ + struct sci_port *s = arg; + struct uart_port *port = &s->port; + struct circ_buf *xmit = &port->state->xmit; + unsigned long flags; + + dev_dbg(port->dev, "%s(%d)\n", __func__, port->line); + + spin_lock_irqsave(&port->lock, flags); + + xmit->tail += sg_dma_len(&s->sg_tx); + xmit->tail &= UART_XMIT_SIZE - 1; + + port->icount.tx += sg_dma_len(&s->sg_tx); + + async_tx_ack(s->desc_tx); + s->cookie_tx = -EINVAL; + s->desc_tx = NULL; + + if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS) + uart_write_wakeup(port); + + if (!uart_circ_empty(xmit)) { + schedule_work(&s->work_tx); + } else if (port->type == PORT_SCIFA || port->type == PORT_SCIFB) { + u16 ctrl = sci_in(port, SCSCR); + sci_out(port, SCSCR, ctrl & ~SCSCR_TIE); + } + + spin_unlock_irqrestore(&port->lock, flags); +} + +/* Locking: called with port lock held */ +static int sci_dma_rx_push(struct sci_port *s, struct tty_struct *tty, + size_t count) +{ + struct uart_port *port = &s->port; + int i, active, room; + + room = tty_buffer_request_room(tty, count); + + if (s->active_rx == s->cookie_rx[0]) { + active = 0; + } else if (s->active_rx == s->cookie_rx[1]) { + active = 1; + } else { + dev_err(port->dev, "cookie %d not found!\n", s->active_rx); + return 0; + } + + if (room < count) + dev_warn(port->dev, "Rx overrun: dropping %u bytes\n", + count - room); + if (!room) + return room; + + for (i = 0; i < room; i++) + tty_insert_flip_char(tty, ((u8 *)sg_virt(&s->sg_rx[active]))[i], + TTY_NORMAL); + + port->icount.rx += room; + + return room; +} + +static void sci_dma_rx_complete(void *arg) +{ + struct sci_port *s = arg; + struct uart_port *port = &s->port; + struct tty_struct *tty = port->state->port.tty; + unsigned long flags; + int count; + + dev_dbg(port->dev, "%s(%d) active #%d\n", __func__, port->line, s->active_rx); + + spin_lock_irqsave(&port->lock, flags); + + count = sci_dma_rx_push(s, tty, s->buf_len_rx); + + mod_timer(&s->rx_timer, jiffies + s->rx_timeout); + + spin_unlock_irqrestore(&port->lock, flags); + + if (count) + tty_flip_buffer_push(tty); + + schedule_work(&s->work_rx); +} + +static void sci_start_rx(struct uart_port *port); +static void sci_start_tx(struct uart_port *port); + +static void sci_rx_dma_release(struct sci_port *s, bool enable_pio) +{ + struct dma_chan *chan = s->chan_rx; + struct uart_port *port = &s->port; + + s->chan_rx = NULL; + s->cookie_rx[0] = s->cookie_rx[1] = -EINVAL; + dma_release_channel(chan); + if (sg_dma_address(&s->sg_rx[0])) + dma_free_coherent(port->dev, s->buf_len_rx * 2, + sg_virt(&s->sg_rx[0]), sg_dma_address(&s->sg_rx[0])); + if (enable_pio) + sci_start_rx(port); +} + +static void sci_tx_dma_release(struct sci_port *s, bool enable_pio) +{ + struct dma_chan *chan = s->chan_tx; + struct uart_port *port = &s->port; + + s->chan_tx = NULL; + s->cookie_tx = -EINVAL; + dma_release_channel(chan); + if (enable_pio) + sci_start_tx(port); +} + +static void sci_submit_rx(struct sci_port *s) +{ + struct dma_chan *chan = s->chan_rx; + int i; + + for (i = 0; i < 2; i++) { + struct scatterlist *sg = &s->sg_rx[i]; + struct dma_async_tx_descriptor *desc; + + desc = chan->device->device_prep_slave_sg(chan, + sg, 1, DMA_FROM_DEVICE, DMA_PREP_INTERRUPT); + + if (desc) { + s->desc_rx[i] = desc; + desc->callback = sci_dma_rx_complete; + desc->callback_param = s; + s->cookie_rx[i] = desc->tx_submit(desc); + } + + if (!desc || s->cookie_rx[i] < 0) { + if (i) { + async_tx_ack(s->desc_rx[0]); + s->cookie_rx[0] = -EINVAL; + } + if (desc) { + async_tx_ack(desc); + s->cookie_rx[i] = -EINVAL; + } + dev_warn(s->port.dev, + "failed to re-start DMA, using PIO\n"); + sci_rx_dma_release(s, true); + return; + } + dev_dbg(s->port.dev, "%s(): cookie %d to #%d\n", __func__, + s->cookie_rx[i], i); + } + + s->active_rx = s->cookie_rx[0]; + + dma_async_issue_pending(chan); +} + +static void work_fn_rx(struct work_struct *work) +{ + struct sci_port *s = container_of(work, struct sci_port, work_rx); + struct uart_port *port = &s->port; + struct dma_async_tx_descriptor *desc; + int new; + + if (s->active_rx == s->cookie_rx[0]) { + new = 0; + } else if (s->active_rx == s->cookie_rx[1]) { + new = 1; + } else { + dev_err(port->dev, "cookie %d not found!\n", s->active_rx); + return; + } + desc = s->desc_rx[new]; + + if (dma_async_is_tx_complete(s->chan_rx, s->active_rx, NULL, NULL) != + DMA_SUCCESS) { + /* Handle incomplete DMA receive */ + struct tty_struct *tty = port->state->port.tty; + struct dma_chan *chan = s->chan_rx; + struct sh_desc *sh_desc = container_of(desc, struct sh_desc, + async_tx); + unsigned long flags; + int count; + + chan->device->device_control(chan, DMA_TERMINATE_ALL, 0); + dev_dbg(port->dev, "Read %u bytes with cookie %d\n", + sh_desc->partial, sh_desc->cookie); + + spin_lock_irqsave(&port->lock, flags); + count = sci_dma_rx_push(s, tty, sh_desc->partial); + spin_unlock_irqrestore(&port->lock, flags); + + if (count) + tty_flip_buffer_push(tty); + + sci_submit_rx(s); + + return; + } + + s->cookie_rx[new] = desc->tx_submit(desc); + if (s->cookie_rx[new] < 0) { + dev_warn(port->dev, "Failed submitting Rx DMA descriptor\n"); + sci_rx_dma_release(s, true); + return; + } + + s->active_rx = s->cookie_rx[!new]; + + dev_dbg(port->dev, "%s: cookie %d #%d, new active #%d\n", __func__, + s->cookie_rx[new], new, s->active_rx); +} + +static void work_fn_tx(struct work_struct *work) +{ + struct sci_port *s = container_of(work, struct sci_port, work_tx); + struct dma_async_tx_descriptor *desc; + struct dma_chan *chan = s->chan_tx; + struct uart_port *port = &s->port; + struct circ_buf *xmit = &port->state->xmit; + struct scatterlist *sg = &s->sg_tx; + + /* + * DMA is idle now. + * Port xmit buffer is already mapped, and it is one page... Just adjust + * offsets and lengths. Since it is a circular buffer, we have to + * transmit till the end, and then the rest. Take the port lock to get a + * consistent xmit buffer state. + */ + spin_lock_irq(&port->lock); + sg->offset = xmit->tail & (UART_XMIT_SIZE - 1); + sg_dma_address(sg) = (sg_dma_address(sg) & ~(UART_XMIT_SIZE - 1)) + + sg->offset; + sg_dma_len(sg) = min((int)CIRC_CNT(xmit->head, xmit->tail, UART_XMIT_SIZE), + CIRC_CNT_TO_END(xmit->head, xmit->tail, UART_XMIT_SIZE)); + spin_unlock_irq(&port->lock); + + BUG_ON(!sg_dma_len(sg)); + + desc = chan->device->device_prep_slave_sg(chan, + sg, s->sg_len_tx, DMA_TO_DEVICE, + DMA_PREP_INTERRUPT | DMA_CTRL_ACK); + if (!desc) { + /* switch to PIO */ + sci_tx_dma_release(s, true); + return; + } + + dma_sync_sg_for_device(port->dev, sg, 1, DMA_TO_DEVICE); + + spin_lock_irq(&port->lock); + s->desc_tx = desc; + desc->callback = sci_dma_tx_complete; + desc->callback_param = s; + spin_unlock_irq(&port->lock); + s->cookie_tx = desc->tx_submit(desc); + if (s->cookie_tx < 0) { + dev_warn(port->dev, "Failed submitting Tx DMA descriptor\n"); + /* switch to PIO */ + sci_tx_dma_release(s, true); + return; + } + + dev_dbg(port->dev, "%s: %p: %d...%d, cookie %d\n", __func__, + xmit->buf, xmit->tail, xmit->head, s->cookie_tx); + + dma_async_issue_pending(chan); +} +#endif + static void sci_start_tx(struct uart_port *port) { + struct sci_port *s = to_sci_port(port); unsigned short ctrl; - /* Set TIE (Transmit Interrupt Enable) bit in SCSCR */ - ctrl = sci_in(port, SCSCR); - ctrl |= SCSCR_TIE; - sci_out(port, SCSCR, ctrl); +#ifdef CONFIG_SERIAL_SH_SCI_DMA + if (port->type == PORT_SCIFA || port->type == PORT_SCIFB) { + u16 new, scr = sci_in(port, SCSCR); + if (s->chan_tx) + new = scr | 0x8000; + else + new = scr & ~0x8000; + if (new != scr) + sci_out(port, SCSCR, new); + } + + if (s->chan_tx && !uart_circ_empty(&s->port.state->xmit) && + s->cookie_tx < 0) + schedule_work(&s->work_tx); +#endif + + if (!s->chan_tx || port->type == PORT_SCIFA || port->type == PORT_SCIFB) { + /* Set TIE (Transmit Interrupt Enable) bit in SCSCR */ + ctrl = sci_in(port, SCSCR); + sci_out(port, SCSCR, ctrl | SCSCR_TIE); + } } static void sci_stop_tx(struct uart_port *port) @@ -871,17 +1256,24 @@ static void sci_stop_tx(struct uart_port *port) /* Clear TIE (Transmit Interrupt Enable) bit in SCSCR */ ctrl = sci_in(port, SCSCR); + + if (port->type == PORT_SCIFA || port->type == PORT_SCIFB) + ctrl &= ~0x8000; + ctrl &= ~SCSCR_TIE; + sci_out(port, SCSCR, ctrl); } -static void sci_start_rx(struct uart_port *port, unsigned int tty_start) +static void sci_start_rx(struct uart_port *port) { unsigned short ctrl; - /* Set RIE (Receive Interrupt Enable) bit in SCSCR */ - ctrl = sci_in(port, SCSCR); - ctrl |= SCSCR_RIE | SCSCR_REIE; + ctrl = sci_in(port, SCSCR) | port_rx_irq_mask(port); + + if (port->type == PORT_SCIFA || port->type == PORT_SCIFB) + ctrl &= ~0x4000; + sci_out(port, SCSCR, ctrl); } @@ -889,9 +1281,13 @@ static void sci_stop_rx(struct uart_port *port) { unsigned short ctrl; - /* Clear RIE (Receive Interrupt Enable) bit in SCSCR */ ctrl = sci_in(port, SCSCR); - ctrl &= ~(SCSCR_RIE | SCSCR_REIE); + + if (port->type == PORT_SCIFA || port->type == PORT_SCIFB) + ctrl &= ~0x4000; + + ctrl &= ~port_rx_irq_mask(port); + sci_out(port, SCSCR, ctrl); } @@ -905,16 +1301,157 @@ static void sci_break_ctl(struct uart_port *port, int break_state) /* Nothing here yet .. */ } +#ifdef CONFIG_SERIAL_SH_SCI_DMA +static bool filter(struct dma_chan *chan, void *slave) +{ + struct sh_dmae_slave *param = slave; + + dev_dbg(chan->device->dev, "%s: slave ID %d\n", __func__, + param->slave_id); + + if (param->dma_dev == chan->device->dev) { + chan->private = param; + return true; + } else { + return false; + } +} + +static void rx_timer_fn(unsigned long arg) +{ + struct sci_port *s = (struct sci_port *)arg; + struct uart_port *port = &s->port; + u16 scr = sci_in(port, SCSCR); + + if (port->type == PORT_SCIFA || port->type == PORT_SCIFB) { + scr &= ~0x4000; + enable_irq(s->irqs[1]); + } + sci_out(port, SCSCR, scr | SCSCR_RIE); + dev_dbg(port->dev, "DMA Rx timed out\n"); + schedule_work(&s->work_rx); +} + +static void sci_request_dma(struct uart_port *port) +{ + struct sci_port *s = to_sci_port(port); + struct sh_dmae_slave *param; + struct dma_chan *chan; + dma_cap_mask_t mask; + int nent; + + dev_dbg(port->dev, "%s: port %d DMA %p\n", __func__, + port->line, s->dma_dev); + + if (!s->dma_dev) + return; + + dma_cap_zero(mask); + dma_cap_set(DMA_SLAVE, mask); + + param = &s->param_tx; + + /* Slave ID, e.g., SHDMA_SLAVE_SCIF0_TX */ + param->slave_id = s->slave_tx; + param->dma_dev = s->dma_dev; + + s->cookie_tx = -EINVAL; + chan = dma_request_channel(mask, filter, param); + dev_dbg(port->dev, "%s: TX: got channel %p\n", __func__, chan); + if (chan) { + s->chan_tx = chan; + sg_init_table(&s->sg_tx, 1); + /* UART circular tx buffer is an aligned page. */ + BUG_ON((int)port->state->xmit.buf & ~PAGE_MASK); + sg_set_page(&s->sg_tx, virt_to_page(port->state->xmit.buf), + UART_XMIT_SIZE, (int)port->state->xmit.buf & ~PAGE_MASK); + nent = dma_map_sg(port->dev, &s->sg_tx, 1, DMA_TO_DEVICE); + if (!nent) + sci_tx_dma_release(s, false); + else + dev_dbg(port->dev, "%s: mapped %d@%p to %x\n", __func__, + sg_dma_len(&s->sg_tx), + port->state->xmit.buf, sg_dma_address(&s->sg_tx)); + + s->sg_len_tx = nent; + + INIT_WORK(&s->work_tx, work_fn_tx); + } + + param = &s->param_rx; + + /* Slave ID, e.g., SHDMA_SLAVE_SCIF0_RX */ + param->slave_id = s->slave_rx; + param->dma_dev = s->dma_dev; + + chan = dma_request_channel(mask, filter, param); + dev_dbg(port->dev, "%s: RX: got channel %p\n", __func__, chan); + if (chan) { + dma_addr_t dma[2]; + void *buf[2]; + int i; + + s->chan_rx = chan; + + s->buf_len_rx = 2 * max(16, (int)port->fifosize); + buf[0] = dma_alloc_coherent(port->dev, s->buf_len_rx * 2, + &dma[0], GFP_KERNEL); + + if (!buf[0]) { + dev_warn(port->dev, + "failed to allocate dma buffer, using PIO\n"); + sci_rx_dma_release(s, true); + return; + } + + buf[1] = buf[0] + s->buf_len_rx; + dma[1] = dma[0] + s->buf_len_rx; + + for (i = 0; i < 2; i++) { + struct scatterlist *sg = &s->sg_rx[i]; + + sg_init_table(sg, 1); + sg_set_page(sg, virt_to_page(buf[i]), s->buf_len_rx, + (int)buf[i] & ~PAGE_MASK); + sg_dma_address(sg) = dma[i]; + } + + INIT_WORK(&s->work_rx, work_fn_rx); + setup_timer(&s->rx_timer, rx_timer_fn, (unsigned long)s); + + sci_submit_rx(s); + } +} + +static void sci_free_dma(struct uart_port *port) +{ + struct sci_port *s = to_sci_port(port); + + if (!s->dma_dev) + return; + + if (s->chan_tx) + sci_tx_dma_release(s, false); + if (s->chan_rx) + sci_rx_dma_release(s, false); +} +#endif + static int sci_startup(struct uart_port *port) { struct sci_port *s = to_sci_port(port); + dev_dbg(port->dev, "%s(%d)\n", __func__, port->line); + if (s->enable) s->enable(port); sci_request_irq(s); +#ifdef CONFIG_SERIAL_SH_SCI_DMA + sci_request_dma(port); +#endif sci_start_tx(port); - sci_start_rx(port, 1); + sci_start_rx(port); return 0; } @@ -923,8 +1460,13 @@ static void sci_shutdown(struct uart_port *port) { struct sci_port *s = to_sci_port(port); + dev_dbg(port->dev, "%s(%d)\n", __func__, port->line); + sci_stop_rx(port); sci_stop_tx(port); +#ifdef CONFIG_SERIAL_SH_SCI_DMA + sci_free_dma(port); +#endif sci_free_irq(s); if (s->disable) @@ -956,11 +1498,22 @@ static void sci_set_termios(struct uart_port *port, struct ktermios *termios, struct ktermios *old) { struct sci_port *s = to_sci_port(port); - unsigned int status, baud, smr_val; + unsigned int status, baud, smr_val, max_baud; int t = -1; + u16 scfcr = 0; + + /* + * earlyprintk comes here early on with port->uartclk set to zero. + * the clock framework is not up and running at this point so here + * we assume that 115200 is the maximum baud rate. please note that + * the baud rate is not programmed during earlyprintk - it is assumed + * that the previous boot loader has enabled required clocks and + * setup the baud rate generator hardware for us already. + */ + max_baud = port->uartclk ? port->uartclk / 16 : 115200; - baud = uart_get_baud_rate(port, termios, old, 0, port->uartclk/16); - if (likely(baud)) + baud = uart_get_baud_rate(port, termios, old, 0, max_baud); + if (likely(baud && port->uartclk)) t = sci_scbrr_calc(s->scbrr_algo_id, baud, port->uartclk); do { @@ -970,7 +1523,7 @@ static void sci_set_termios(struct uart_port *port, struct ktermios *termios, sci_out(port, SCSCR, 0x00); /* TE=0, RE=0, CKE1=0 */ if (port->type != PORT_SCI) - sci_out(port, SCFCR, SCFCR_RFRST | SCFCR_TFRST); + sci_out(port, SCFCR, scfcr | SCFCR_RFRST | SCFCR_TFRST); smr_val = sci_in(port, SCSMR) & 3; if ((termios->c_cflag & CSIZE) == CS7) @@ -986,6 +1539,9 @@ static void sci_set_termios(struct uart_port *port, struct ktermios *termios, sci_out(port, SCSMR, smr_val); + dev_dbg(port->dev, "%s: SMR %x, t %x, SCSCR %x\n", __func__, smr_val, t, + SCSCR_INIT(port)); + if (t > 0) { if (t >= 256) { sci_out(port, SCSMR, (sci_in(port, SCSMR) & ~3) | 1); @@ -998,12 +1554,34 @@ static void sci_set_termios(struct uart_port *port, struct ktermios *termios, } sci_init_pins(port, termios->c_cflag); - sci_out(port, SCFCR, (termios->c_cflag & CRTSCTS) ? SCFCR_MCE : 0); + sci_out(port, SCFCR, scfcr | ((termios->c_cflag & CRTSCTS) ? SCFCR_MCE : 0)); sci_out(port, SCSCR, s->scscr); +#ifdef CONFIG_SERIAL_SH_SCI_DMA + /* + * Calculate delay for 1.5 DMA buffers: see + * drivers/serial/serial_core.c::uart_update_timeout(). With 10 bits + * (CS8), 250Hz, 115200 baud and 64 bytes FIFO, the above function + * calculates 1 jiffie for the data plus 5 jiffies for the "slop(e)." + * Then below we calculate 3 jiffies (12ms) for 1.5 DMA buffers (3 FIFO + * sizes), but it has been found out experimentally, that this is not + * enough: the driver too often needlessly runs on a DMA timeout. 20ms + * as a minimum seem to work perfectly. + */ + if (s->chan_rx) { + s->rx_timeout = (port->timeout - HZ / 50) * s->buf_len_rx * 3 / + port->fifosize / 2; + dev_dbg(port->dev, + "DMA Rx t-out %ums, tty t-out %u jiffies\n", + s->rx_timeout * 1000 / HZ, port->timeout); + if (s->rx_timeout < msecs_to_jiffies(20)) + s->rx_timeout = msecs_to_jiffies(20); + } +#endif + if ((termios->c_cflag & CREAD) != 0) - sci_start_rx(port, 0); + sci_start_rx(port); } static const char *sci_type(struct uart_port *port) @@ -1017,6 +1595,8 @@ static const char *sci_type(struct uart_port *port) return "scif"; case PORT_SCIFA: return "scifa"; + case PORT_SCIFB: + return "scifb"; } return NULL; @@ -1093,45 +1673,79 @@ static struct uart_ops sci_uart_ops = { #endif }; -static void __devinit sci_init_single(struct platform_device *dev, - struct sci_port *sci_port, - unsigned int index, - struct plat_sci_port *p) +static int __devinit sci_init_single(struct platform_device *dev, + struct sci_port *sci_port, + unsigned int index, + struct plat_sci_port *p) { - sci_port->port.ops = &sci_uart_ops; - sci_port->port.iotype = UPIO_MEM; - sci_port->port.line = index; - sci_port->port.fifosize = 1; + struct uart_port *port = &sci_port->port; -#if defined(__H8300H__) || defined(__H8300S__) -#ifdef __H8300S__ - sci_port->enable = h8300_sci_enable; - sci_port->disable = h8300_sci_disable; -#endif - sci_port->port.uartclk = CONFIG_CPU_CLOCK; -#elif defined(CONFIG_HAVE_CLK) - sci_port->iclk = p->clk ? clk_get(&dev->dev, p->clk) : NULL; - sci_port->dclk = clk_get(&dev->dev, "peripheral_clk"); - sci_port->enable = sci_clk_enable; - sci_port->disable = sci_clk_disable; -#else -#error "Need a valid uartclk" -#endif + port->ops = &sci_uart_ops; + port->iotype = UPIO_MEM; + port->line = index; + + switch (p->type) { + case PORT_SCIFB: + port->fifosize = 256; + break; + case PORT_SCIFA: + port->fifosize = 64; + break; + case PORT_SCIF: + port->fifosize = 16; + break; + default: + port->fifosize = 1; + break; + } + + if (dev) { + sci_port->iclk = clk_get(&dev->dev, "sci_ick"); + if (IS_ERR(sci_port->iclk)) { + sci_port->iclk = clk_get(&dev->dev, "peripheral_clk"); + if (IS_ERR(sci_port->iclk)) { + dev_err(&dev->dev, "can't get iclk\n"); + return PTR_ERR(sci_port->iclk); + } + } + + /* + * The function clock is optional, ignore it if we can't + * find it. + */ + sci_port->fclk = clk_get(&dev->dev, "sci_fck"); + if (IS_ERR(sci_port->fclk)) + sci_port->fclk = NULL; + + sci_port->enable = sci_clk_enable; + sci_port->disable = sci_clk_disable; + port->dev = &dev->dev; + } sci_port->break_timer.data = (unsigned long)sci_port; sci_port->break_timer.function = sci_break_timer; init_timer(&sci_port->break_timer); - sci_port->port.mapbase = p->mapbase; - sci_port->port.membase = p->membase; + port->mapbase = p->mapbase; + port->membase = p->membase; + port->irq = p->irqs[SCIx_TXI_IRQ]; + port->flags = p->flags; + sci_port->type = port->type = p->type; sci_port->scscr = p->scscr; - sci_port->port.irq = p->irqs[SCIx_TXI_IRQ]; - sci_port->port.flags = p->flags; - sci_port->port.dev = &dev->dev; - sci_port->type = sci_port->port.type = p->type; + sci_port->scbrr_algo_id = p->scbrr_algo_id; + +#ifdef CONFIG_SERIAL_SH_SCI_DMA + sci_port->dma_dev = p->dma_dev; + sci_port->slave_tx = p->dma_slave_tx; + sci_port->slave_rx = p->dma_slave_rx; + + dev_dbg(port->dev, "%s: DMA device %p, tx %d, rx %d\n", __func__, + p->dma_dev, p->dma_slave_tx, p->dma_slave_rx); +#endif memcpy(&sci_port->irqs, &p->irqs, sizeof(p->irqs)); + return 0; } #ifdef CONFIG_SERIAL_SH_SCI_CONSOLE @@ -1168,11 +1782,11 @@ static void serial_console_write(struct console *co, const char *s, while ((sci_in(port, SCxSR) & bits) != bits) cpu_relax(); - if (sci_port->disable); + if (sci_port->disable) sci_port->disable(port); } -static int __init serial_console_setup(struct console *co, char *options) +static int __devinit serial_console_setup(struct console *co, char *options) { struct sci_port *sci_port; struct uart_port *port; @@ -1190,9 +1804,14 @@ static int __init serial_console_setup(struct console *co, char *options) if (co->index >= SCI_NPORTS) co->index = 0; - sci_port = &sci_ports[co->index]; - port = &sci_port->port; - co->data = port; + if (co->data) { + port = co->data; + sci_port = to_sci_port(port); + } else { + sci_port = &sci_ports[co->index]; + port = &sci_port->port; + co->data = port; + } /* * Also need to check port->type, we don't actually have any @@ -1236,6 +1855,15 @@ static int __init sci_console_init(void) return 0; } console_initcall(sci_console_init); + +static struct sci_port early_serial_port; +static struct console early_serial_console = { + .name = "early_ttySC", + .write = serial_console_write, + .flags = CON_PRINTBUFFER, +}; +static char early_serial_buf[32]; + #endif /* CONFIG_SERIAL_SH_SCI_CONSOLE */ #if defined(CONFIG_SERIAL_SH_SCI_CONSOLE) @@ -1264,14 +1892,14 @@ static int sci_remove(struct platform_device *dev) struct sci_port *p; unsigned long flags; -#ifdef CONFIG_HAVE_CLK cpufreq_unregister_notifier(&priv->clk_nb, CPUFREQ_TRANSITION_NOTIFIER); -#endif spin_lock_irqsave(&priv->lock, flags); - list_for_each_entry(p, &priv->ports, node) + list_for_each_entry(p, &priv->ports, node) { uart_remove_one_port(&sci_uart_driver, &p->port); - + clk_put(p->iclk); + clk_put(p->fclk); + } spin_unlock_irqrestore(&priv->lock, flags); kfree(priv); @@ -1297,7 +1925,9 @@ static int __devinit sci_probe_single(struct platform_device *dev, return 0; } - sci_init_single(dev, sciport, index, p); + ret = sci_init_single(dev, sciport, index, p); + if (ret) + return ret; ret = uart_add_one_port(&sci_uart_driver, &sciport->port); if (ret) @@ -1324,6 +1954,21 @@ static int __devinit sci_probe(struct platform_device *dev) struct sh_sci_priv *priv; int i, ret = -EINVAL; +#ifdef CONFIG_SERIAL_SH_SCI_CONSOLE + if (is_early_platform_device(dev)) { + if (dev->id == -1) + return -ENOTSUPP; + early_serial_console.index = dev->id; + early_serial_console.data = &early_serial_port.port; + sci_init_single(NULL, &early_serial_port, dev->id, p); + serial_console_setup(&early_serial_console, early_serial_buf); + if (!strstr(early_serial_buf, "keep")) + early_serial_console.flags |= CON_BOOT; + register_console(&early_serial_console); + return 0; + } +#endif + priv = kzalloc(sizeof(*priv), GFP_KERNEL); if (!priv) return -ENOMEM; @@ -1332,10 +1977,8 @@ static int __devinit sci_probe(struct platform_device *dev) spin_lock_init(&priv->lock); platform_set_drvdata(dev, priv); -#ifdef CONFIG_HAVE_CLK priv->clk_nb.notifier_call = sci_notifier; cpufreq_register_notifier(&priv->clk_nb, CPUFREQ_TRANSITION_NOTIFIER); -#endif if (dev->id != -1) { ret = sci_probe_single(dev, dev->id, p, &sci_ports[dev->id]); @@ -1388,14 +2031,14 @@ static int sci_resume(struct device *dev) return 0; } -static struct dev_pm_ops sci_dev_pm_ops = { +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 = __devexit_p(sci_remove), + .remove = sci_remove, .driver = { .name = "sh-sci", .owner = THIS_MODULE, @@ -1425,6 +2068,10 @@ static void __exit sci_exit(void) 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); |