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Thu, 18 Feb 2010 17:30:07 +0100 Date: Thu, 18 Feb 2010 17:30:07 +0100 (CET) From: Guennadi Liakhovetski To: "linux-sh@vger.kernel.org" cc: Magnus Damm , Dan Williams , linux-serial@vger.kernel.org Subject: [PATCH 2/2] Add DMA support for the sh-sci.c serial driver In-Reply-To: Message-ID: References: MIME-Version: 1.0 X-Y-GMX-Trusted: 0 X-FuHaFi: 0.41999999999999998 Sender: linux-sh-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-sh@vger.kernel.org X-Greylist: IP, sender and recipient auto-whitelisted, not delayed by milter-greylist-4.2.3 (demeter.kernel.org [140.211.167.41]); Thu, 18 Feb 2010 16:30:19 +0000 (UTC) diff --git a/drivers/serial/Kconfig b/drivers/serial/Kconfig index 9a8e9f0..52f28e1 100644 --- a/drivers/serial/Kconfig +++ b/drivers/serial/Kconfig @@ -1016,6 +1016,12 @@ config SERIAL_SH_SCI_CONSOLE depends on SERIAL_SH_SCI=y select SERIAL_CORE_CONSOLE +config SH_SCI_USE_DMA + bool "DMA support" + depends on SERIAL_SH_SCI + select DMADEVICES + select SH_DMAE + config SERIAL_PNX8XXX bool "Enable PNX8XXX SoCs' UART Support" depends on MIPS && (SOC_PNX8550 || SOC_PNX833X) diff --git a/drivers/serial/sh-sci.c b/drivers/serial/sh-sci.c index 2cf3b6d..36e608e 100644 --- a/drivers/serial/sh-sci.c +++ b/drivers/serial/sh-sci.c @@ -48,6 +48,9 @@ #include #include #include +#include +#include +#include #ifdef CONFIG_SUPERH #include @@ -84,6 +87,27 @@ struct sci_port { struct clk *dclk; struct list_head node; + struct dma_chan *chan_tx; + struct dma_chan *chan_rx; +#ifdef CONFIG_SH_SCI_USE_DMA + struct device *dma_dev; + enum sh_dmae_slave_chan_id slave_tx; + enum sh_dmae_slave_chan_id 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; +#endif }; struct sh_sci_priv { @@ -273,29 +297,44 @@ 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 SCIF_TXROOM_MAX - (sci_in(port, SCTFDR) & 0xff); + return sci_in(port, SCTFDR) & 0xff; } -static inline int scif_rxroom(struct uart_port *port) +static int scif_txroom(struct uart_port *port) +{ + return SCIF_TXROOM_MAX - scif_txfill(port); +} + +static int scif_rxfill(struct uart_port *port) { return sci_in(port, SCRFDR) & 0xff; } #elif defined(CONFIG_CPU_SUBTYPE_SH7763) -static 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 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 inline int scif_rxroom(struct uart_port *port) +static int scif_rxfill(struct uart_port *port) { if ((port->mapbase == 0xffe00000) || (port->mapbase == 0xffe08000)) { @@ -307,23 +346,33 @@ static inline int scif_rxroom(struct uart_port *port) } } #else -static inline int scif_txroom(struct uart_port *port) +static int scif_txfill(struct uart_port *port) { - return SCIF_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) +{ + return SCIF_TXROOM_MAX - scif_txfill(port); +} + +static int scif_rxfill(struct uart_port *port) { return sci_in(port, SCFDR) & SCIF_RFDC_MASK; } #endif -static 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; } @@ -410,9 +459,9 @@ 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); @@ -457,10 +506,10 @@ 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 @@ -622,13 +671,39 @@ 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_SH_SCI_USE_DMA + struct uart_port *port = ptr; + struct sci_port *s = to_sci_port(port); + + if (s->chan_rx) { + unsigned long tout; + u16 scr = sci_in(port, SCSCR); + u16 ssr = sci_in(port, SCxSR); + + /* Disable future Rx interrupts */ + sci_out(port, SCSCR, scr & ~SCI_CTRL_FLAGS_RIE); + /* Clear current interrupt */ + sci_out(port, SCxSR, ssr & ~(1 | SCxSR_RDxF(port))); + /* Calculate delay for 1.5 DMA buffers */ + tout = (port->timeout - HZ / 50) * s->buf_len_rx * 3 / + port->fifosize / 2; + dev_dbg(port->dev, "Rx IRQ: setup timeout in %u ms\n", + tout * 1000 / HZ); + if (tout < 2) + tout = 2; + mod_timer(&s->rx_timer, jiffies + tout); + + 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; } @@ -684,6 +759,9 @@ static irqreturn_t sci_mpxed_interrupt(int irq, void *ptr) { unsigned short ssr_status, scr_status, err_enabled; struct uart_port *port = ptr; +#ifdef CONFIG_SH_SCI_USE_DMA + struct sci_port *s = to_sci_port(port); +#endif irqreturn_t ret = IRQ_NONE; ssr_status = sci_in(port, SCxSR); @@ -691,10 +769,15 @@ static irqreturn_t sci_mpxed_interrupt(int irq, void *ptr) err_enabled = scr_status & (SCI_CTRL_FLAGS_REIE | SCI_CTRL_FLAGS_RIE); /* Tx Interrupt */ - if ((ssr_status & SCxSR_TDxE(port)) && (scr_status & SCI_CTRL_FLAGS_TIE)) + if ((ssr_status & SCxSR_TDxE(port)) && (scr_status & SCI_CTRL_FLAGS_TIE) && + !s->chan_tx) ret = sci_tx_interrupt(irq, ptr); - /* Rx Interrupt */ - if ((ssr_status & SCxSR_RDxF(port)) && (scr_status & SCI_CTRL_FLAGS_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 & SCI_CTRL_FLAGS_RIE)) ret = sci_rx_interrupt(irq, ptr); /* Error Interrupt */ if ((ssr_status & SCxSR_ERRORS(port)) && err_enabled) @@ -703,6 +786,10 @@ static irqreturn_t sci_mpxed_interrupt(int irq, void *ptr) if ((ssr_status & SCxSR_BRK(port)) && err_enabled) ret = sci_br_interrupt(irq, ptr); + WARN_ONCE(ret == IRQ_NONE, + "%s: %d IRQ %d, status %x, control %x\n", __func__, + irq, port->line, ssr_status, scr_status); + return ret; } @@ -804,7 +891,9 @@ static void sci_free_irq(struct sci_port *port) static unsigned int sci_tx_empty(struct uart_port *port) { unsigned short status = sci_in(port, SCxSR); - return status & SCxSR_TEND(port) ? TIOCSER_TEMT : 0; + 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) @@ -816,16 +905,301 @@ 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_SH_SCI_USE_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 += s->sg_tx.length; + xmit->tail &= UART_XMIT_SIZE - 1; + + port->icount.tx += s->sg_tx.length; + + async_tx_ack(s->desc_tx); + s->cookie_tx = -EINVAL; + s->desc_tx = NULL; + + spin_unlock_irqrestore(&port->lock, flags); + + if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS) + uart_write_wakeup(port); + + if (uart_circ_chars_pending(xmit)) + schedule_work(&s->work_tx); +} + +/* 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)\n", __func__, port->line); + + spin_lock_irqsave(&port->lock, flags); + + count = sci_dma_rx_push(s, tty, s->buf_len_rx); + + mod_timer(&s->rx_timer, jiffies + msecs_to_jiffies(5)); + + 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; + unsigned long flags; + + s->chan_rx = NULL; + s->cookie_rx[0] = s->cookie_rx[1] = -EINVAL; + dma_release_channel(chan); + 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; + unsigned long flags; + + 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; + } + } + + s->active_rx = s->cookie_rx[0]; + + dma_async_issue_pending(chan); + + return; +} + +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_terminate_all(chan); + 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; + } + + dev_dbg(port->dev, "%s: cookie %d #%d\n", __func__, + s->cookie_rx[new], new); + + s->active_rx = s->cookie_rx[!new]; +} + +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_dma_address(sg) & ~(UART_XMIT_SIZE - 1)) + + sg->offset; + sg->length = min((int)CIRC_CNT(xmit->head, xmit->tail, UART_XMIT_SIZE), + CIRC_CNT_TO_END(xmit->head, xmit->tail, UART_XMIT_SIZE)); + sg->dma_length = sg->length; + spin_unlock_irq(&port->lock); + + BUG_ON(!sg->length); + + 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) { unsigned short ctrl; +#ifdef CONFIG_SH_SCI_USE_DMA + struct sci_port *s = to_sci_port(port); + + if (s->chan_tx) { + if (!uart_circ_empty(&s->port.state->xmit) && s->cookie_tx < 0) + schedule_work(&s->work_tx); + + return; + } +#endif + /* Set TIE (Transmit Interrupt Enable) bit in SCSCR */ ctrl = sci_in(port, SCSCR); ctrl |= SCI_CTRL_FLAGS_TIE; @@ -842,13 +1216,12 @@ static void sci_stop_tx(struct uart_port *port) 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; + unsigned short ctrl = SCI_CTRL_FLAGS_RIE | SCI_CTRL_FLAGS_REIE; /* Set RIE (Receive Interrupt Enable) bit in SCSCR */ - ctrl = sci_in(port, SCSCR); - ctrl |= SCI_CTRL_FLAGS_RIE | SCI_CTRL_FLAGS_REIE; + ctrl |= sci_in(port, SCSCR); sci_out(port, SCSCR, ctrl); } @@ -872,16 +1245,154 @@ static void sci_break_ctl(struct uart_port *port, int break_state) /* Nothing here yet .. */ } +#ifdef CONFIG_SH_SCI_USE_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); + sci_out(port, SCSCR, scr | SCI_CTRL_FLAGS_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 = dma[i]; + sg->dma_length = sg->length; + } + + 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_SH_SCI_USE_DMA + sci_request_dma(port); +#endif sci_start_tx(port); - sci_start_rx(port, 1); + sci_start_rx(port); return 0; } @@ -890,8 +1401,13 @@ 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_SH_SCI_USE_DMA + sci_free_dma(port); +#endif sci_free_irq(s); if (s->disable) @@ -941,6 +1457,9 @@ 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); @@ -958,7 +1477,7 @@ static void sci_set_termios(struct uart_port *port, struct ktermios *termios, sci_out(port, SCSCR, SCSCR_INIT(port)); if ((termios->c_cflag & CREAD) != 0) - sci_start_rx(port, 0); + sci_start_rx(port); } static const char *sci_type(struct uart_port *port) @@ -1053,19 +1572,21 @@ static void __devinit sci_init_single(struct platform_device *dev, 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; + struct uart_port *port = &sci_port->port; + + port->ops = &sci_uart_ops; + port->iotype = UPIO_MEM; + port->line = index; switch (p->type) { case PORT_SCIFA: - sci_port->port.fifosize = 64; + port->fifosize = 64; break; case PORT_SCIF: - sci_port->port.fifosize = 16; + port->fifosize = 16; break; default: - sci_port->port.fifosize = 1; + port->fifosize = 1; break; } @@ -1074,19 +1595,28 @@ static void __devinit sci_init_single(struct platform_device *dev, sci_port->dclk = clk_get(&dev->dev, "peripheral_clk"); sci_port->enable = sci_clk_enable; sci_port->disable = sci_clk_disable; - sci_port->port.dev = &dev->dev; + 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; - sci_port->port.irq = p->irqs[SCIx_TXI_IRQ]; - sci_port->port.flags = p->flags; - sci_port->type = sci_port->port.type = p->type; + port->irq = p->irqs[SCIx_TXI_IRQ]; + port->flags = p->flags; + sci_port->type = port->type = p->type; + +#ifdef CONFIG_SH_SCI_USE_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)); } diff --git a/include/linux/serial_sci.h b/include/linux/serial_sci.h index 1c297dd..1b177d2 100644 --- a/include/linux/serial_sci.h +++ b/include/linux/serial_sci.h @@ -2,6 +2,7 @@ #define __LINUX_SERIAL_SCI_H #include +#include /* * Generic header for SuperH SCI(F) (used by sh/sh64/h8300 and related parts) @@ -16,6 +17,8 @@ enum { SCIx_NR_IRQS, }; +struct device; + /* * Platform device specific platform_data struct */ @@ -26,6 +29,9 @@ struct plat_sci_port { unsigned int type; /* SCI / SCIF / IRDA */ upf_t flags; /* UPF_* flags */ char *clk; /* clock string */ + struct device *dma_dev; + enum sh_dmae_slave_chan_id dma_slave_tx; + enum sh_dmae_slave_chan_id dma_slave_rx; }; #endif /* __LINUX_SERIAL_SCI_H */