1 files changed, 135 insertions, 67 deletions

diff --git a/drivers/serial/sh-sci.c b/drivers/serial/sh-sci.c
index 8eb094c1f61b..5f90fcd7d107 100644
--- a/drivers/serial/sh-sci.c
+++ b/drivers/serial/sh-sci.c
@@ -83,16 +83,16 @@ struct sci_port {
 
         /* Interface clock */
         struct clk              *iclk;
-        /* Data clock */
-        struct clk              *dclk;
+        /* 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;
-        enum sh_dmae_slave_chan_id      slave_tx;
-        enum sh_dmae_slave_chan_id      slave_rx;
+        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;
@@ -107,6 +107,7 @@ struct sci_port {
         struct work_struct              work_tx;
         struct work_struct              work_rx;
         struct timer_list               rx_timer;
+        unsigned int                    rx_timeout;
 #endif
 };
 
@@ -150,7 +151,11 @@ 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);
 
@@ -674,22 +679,22 @@ static irqreturn_t sci_rx_interrupt(int irq, void *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);
+                if (port->type == PORT_SCIFA) {
+                        disable_irq_nosync(irq);
+                        scr |= 0x4000;
+                } else {
+                        scr &= ~SCI_CTRL_FLAGS_RIE;
+                }
+                sci_out(port, SCSCR, scr);
                 /* 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 %lu ms\n",
-                        tout * 1000 / HZ);
-                if (tout < 2)
-                        tout = 2;
-                mod_timer(&s->rx_timer, jiffies + tout);
+                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;
         }
@@ -799,7 +804,7 @@ 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);
         }
 
@@ -810,21 +815,17 @@ 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);
 }
 
 static int sci_request_irq(struct sci_port *port)
@@ -913,22 +914,26 @@ static void sci_dma_tx_complete(void *arg)
 
         spin_lock_irqsave(&port->lock, flags);
 
-        xmit->tail += s->sg_tx.length;
+        xmit->tail += sg_dma_len(&s->sg_tx);
         xmit->tail &= UART_XMIT_SIZE - 1;
 
-        port->icount.tx += s->sg_tx.length;
+        port->icount.tx += sg_dma_len(&s->sg_tx);
 
         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))
+        if (!uart_circ_empty(xmit)) {
                 schedule_work(&s->work_tx);
+        } else if (port->type == PORT_SCIFA) {
+                u16 ctrl = sci_in(port, SCSCR);
+                sci_out(port, SCSCR, ctrl & ~SCI_CTRL_FLAGS_TIE);
+        }
+
+        spin_unlock_irqrestore(&port->lock, flags);
 }
 
 /* Locking: called with port lock held */
@@ -972,13 +977,13 @@ static void sci_dma_rx_complete(void *arg)
         unsigned long flags;
         int count;
 
-        dev_dbg(port->dev, "%s(%d)\n", __func__, port->line);
+        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 + msecs_to_jiffies(5));
+        mod_timer(&s->rx_timer, jiffies + s->rx_timeout);
 
         spin_unlock_irqrestore(&port->lock, flags);
 
@@ -999,8 +1004,9 @@ static void sci_rx_dma_release(struct sci_port *s, bool enable_pio)
         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 (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);
 }
@@ -1050,6 +1056,8 @@ static void sci_submit_rx(struct sci_port *s)
                         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];
@@ -1084,7 +1092,7 @@ static void work_fn_rx(struct work_struct *work)
                 unsigned long flags;
                 int count;
 
-                chan->device->device_terminate_all(chan);
+                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);
 
@@ -1107,10 +1115,10 @@ static void work_fn_rx(struct work_struct *work)
                 return;
         }
 
-        dev_dbg(port->dev, "%s: cookie %d #%d\n", __func__,
-                s->cookie_rx[new], new);
-
         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)
@@ -1131,14 +1139,13 @@ static void work_fn_tx(struct work_struct *work)
          */
         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_dma_address(sg) = (sg_dma_address(sg) & ~(UART_XMIT_SIZE - 1)) +
                 sg->offset;
-        sg->length = min((int)CIRC_CNT(xmit->head, xmit->tail, UART_XMIT_SIZE),
+        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));
-        sg->dma_length = sg->length;
         spin_unlock_irq(&port->lock);
 
-        BUG_ON(!sg->length);
+        BUG_ON(!sg_dma_len(sg));
 
         desc = chan->device->device_prep_slave_sg(chan,
                         sg, s->sg_len_tx, DMA_TO_DEVICE,
@@ -1173,23 +1180,28 @@ static void work_fn_tx(struct work_struct *work)
 
 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
-        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;
+        if (port->type == PORT_SCIFA) {
+                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
-
-        /* Set TIE (Transmit Interrupt Enable) bit in SCSCR */
-        ctrl = sci_in(port, SCSCR);
-        ctrl |= SCI_CTRL_FLAGS_TIE;
-        sci_out(port, SCSCR, ctrl);
+        if (!s->chan_tx || port->type == PORT_SCIFA) {
+                /* Set TIE (Transmit Interrupt Enable) bit in SCSCR */
+                ctrl = sci_in(port, SCSCR);
+                sci_out(port, SCSCR, ctrl | SCI_CTRL_FLAGS_TIE);
+        }
 }
 
 static void sci_stop_tx(struct uart_port *port)
@@ -1198,6 +1210,8 @@ 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)
+                ctrl &= ~0x8000;
         ctrl &= ~SCI_CTRL_FLAGS_TIE;
         sci_out(port, SCSCR, ctrl);
 }
@@ -1208,6 +1222,8 @@ static void sci_start_rx(struct uart_port *port)
 
         /* Set RIE (Receive Interrupt Enable) bit in SCSCR */
         ctrl |= sci_in(port, SCSCR);
+        if (port->type == PORT_SCIFA)
+                ctrl &= ~0x4000;
         sci_out(port, SCSCR, ctrl);
 }
 
@@ -1217,6 +1233,8 @@ static void sci_stop_rx(struct uart_port *port)
 
         /* Clear RIE (Receive Interrupt Enable) bit in SCSCR */
         ctrl = sci_in(port, SCSCR);
+        if (port->type == PORT_SCIFA)
+                ctrl &= ~0x4000;
         ctrl &= ~(SCI_CTRL_FLAGS_RIE | SCI_CTRL_FLAGS_REIE);
         sci_out(port, SCSCR, ctrl);
 }
@@ -1251,8 +1269,12 @@ 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) {
+                scr &= ~0x4000;
+                enable_irq(s->irqs[1]);
+        }
         sci_out(port, SCSCR, scr | SCI_CTRL_FLAGS_RIE);
         dev_dbg(port->dev, "DMA Rx timed out\n");
         schedule_work(&s->work_rx);
@@ -1339,8 +1361,7 @@ static void sci_request_dma(struct uart_port *port)
                         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;
+                        sg_dma_address(sg) = dma[i];
                 }
 
                 INIT_WORK(&s->work_rx, work_fn_rx);
@@ -1403,8 +1424,12 @@ static void sci_shutdown(struct uart_port *port)
 static void sci_set_termios(struct uart_port *port, struct ktermios *termios,
                             struct ktermios *old)
 {
+#ifdef CONFIG_SERIAL_SH_SCI_DMA
+        struct sci_port *s = to_sci_port(port);
+#endif
         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.
@@ -1427,7 +1452,7 @@ 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)
@@ -1458,10 +1483,32 @@ 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, SCSCR_INIT(port));
 
+#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);
 }
@@ -1553,10 +1600,10 @@ 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)
 {
         struct uart_port *port = &sci_port->port;
 
@@ -1577,8 +1624,23 @@ static void __devinit sci_init_single(struct platform_device *dev,
         }
 
         if (dev) {
-                sci_port->iclk = p->clk ? clk_get(&dev->dev, p->clk) : NULL;
-                sci_port->dclk = clk_get(&dev->dev, "peripheral_clk");
+                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;
@@ -1605,6 +1667,7 @@ static void __devinit sci_init_single(struct platform_device *dev,
 #endif
 
         memcpy(&sci_port->irqs, &p->irqs, sizeof(p->irqs));
+        return 0;
 }
 
 #ifdef CONFIG_SERIAL_SH_SCI_CONSOLE
@@ -1754,8 +1817,11 @@ static int sci_remove(struct platform_device *dev)
         cpufreq_unregister_notifier(&priv->clk_nb, CPUFREQ_TRANSITION_NOTIFIER);
 
         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);
@@ -1781,7 +1847,9 @@ 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)