From: Koji Matsuoka <koji.matsuoka.xm@xxxxxxxxxxx>
Signed-off-by: Koji Matsuoka <koji.matsuoka.xm@xxxxxxxxxxx>
Signed-off-by: Kazuya Mizuguchi <kazuya.mizuguchi.ks@xxxxxxxxxxx>
Signed-off-by: Yoshihiro Kaneko <ykaneko0929@xxxxxxxxx>
---
This patch is based on the tty-next branch of Greg Kroah-Hartman's tty
tree.
This patch is the result of squashing two patches.
One, of the same name, by Koji Matsuoka. And a second small fix by
Kazuya Mizuguchi. Accordingly I have included both authors signed-off-by
lines above.
drivers/tty/serial/sh-sci.c | 142 +++++++++++++++++++++++++++++++++++---------
1 file changed, 114 insertions(+), 28 deletions(-)
diff --git a/drivers/tty/serial/sh-sci.c b/drivers/tty/serial/sh-sci.c
index e7d6566..65cc72a 100644
--- a/drivers/tty/serial/sh-sci.c
+++ b/drivers/tty/serial/sh-sci.c
@@ -1,4 +1,8 @@
/*
+ * drivers/tty/serial/sh-sci.c
+ *
+ * Copyright (C) 2014 Renesas Electronics Corporation
+ *
* SuperH on-chip serial module support. (SCI with no FIFO / with FIFO)
*
* Copyright (C) 2002 - 2011 Paul Mundt
@@ -103,13 +107,13 @@ struct sci_port {
#ifdef CONFIG_SERIAL_SH_SCI_DMA
struct dma_async_tx_descriptor *desc_tx;
- struct dma_async_tx_descriptor *desc_rx[2];
+ struct dma_async_tx_descriptor *desc_rx[3];
dma_cookie_t cookie_tx;
- dma_cookie_t cookie_rx[2];
+ dma_cookie_t cookie_rx[3];
dma_cookie_t active_rx;
struct scatterlist sg_tx;
unsigned int sg_len_tx;
- struct scatterlist sg_rx[2];
+ struct scatterlist sg_rx[3];
size_t buf_len_rx;
struct sh_dmae_slave param_tx;
struct sh_dmae_slave param_rx;
@@ -117,6 +121,8 @@ struct sci_port {
struct work_struct work_rx;
struct timer_list rx_timer;
unsigned int rx_timeout;
+ int rx_flag;
+ int rx_release_flag;
#endif
struct notifier_block freq_transition;
@@ -1300,6 +1306,8 @@ static int sci_dma_rx_push(struct sci_port *s, size_t count)
active = 0;
} else if (s->active_rx == s->cookie_rx[1]) {
active = 1;
+ } else if (s->active_rx == s->cookie_rx[2]) {
+ active = 2;
} else {
dev_err(port->dev, "cookie %d not found!\n", s->active_rx);
return 0;
@@ -1332,7 +1340,14 @@ static void sci_dma_rx_complete(void *arg)
spin_lock_irqsave(&port->lock, flags);
- count = sci_dma_rx_push(s, s->buf_len_rx);
+ s->rx_flag = 1;
+
+ if ((port->type == PORT_SCIF || port->type == PORT_HSCIF) &&
+ s->active_rx == s->cookie_rx[0]) {
+ count = sci_dma_rx_push(s, 1);
+ async_tx_ack(s->desc_rx[0]);
+ } else
+ count = sci_dma_rx_push(s, s->buf_len_rx);
mod_timer(&s->rx_timer, jiffies + s->rx_timeout);
@@ -1348,13 +1363,26 @@ 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;
+ size_t buf_len_rx;
+ int t = 100000;
+
+ s->rx_release_flag = 1;
+ while (t--) {
+ if (!s->rx_flag)
+ break;
+ usleep_range(10, 50);
+ }
s->chan_rx = NULL;
- s->cookie_rx[0] = s->cookie_rx[1] = -EINVAL;
+ s->cookie_rx[0] = s->cookie_rx[1] = s->cookie_rx[2] = -EINVAL;
+ if (port->type == PORT_SCIF || port->type == PORT_HSCIF)
+ buf_len_rx = 1 + s->buf_len_rx * 2;
+ else
+ buf_len_rx = s->buf_len_rx * 2;
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]));
+ dma_free_coherent(port->dev, buf_len_rx, sg_virt(&s->sg_rx[0]),
+ sg_dma_address(&s->sg_rx[0]));
if (enable_pio)
sci_start_rx(port);
}
@@ -1374,9 +1402,15 @@ static void sci_tx_dma_release(struct sci_port *s, bool enable_pio)
static void sci_submit_rx(struct sci_port *s)
{
struct dma_chan *chan = s->chan_rx;
+ struct uart_port *port = &s->port;
int i;
+ int j;
+ int nr_descs = 2;
- for (i = 0; i < 2; i++) {
+ if (port->type == PORT_SCIF || port->type == PORT_HSCIF)
+ nr_descs = 3;
+
+ for (i = 0; i < nr_descs; i++) {
struct scatterlist *sg = &s->sg_rx[i];
struct dma_async_tx_descriptor *desc;
@@ -1392,8 +1426,10 @@ static void sci_submit_rx(struct sci_port *s)
if (!desc || s->cookie_rx[i] < 0) {
if (i) {
- async_tx_ack(s->desc_rx[0]);
- s->cookie_rx[0] = -EINVAL;
+ for (j = 0; j < i; j++) {
+ async_tx_ack(s->desc_rx[j]);
+ s->cookie_rx[j] = -EINVAL;
+ }
}
if (desc) {
async_tx_ack(desc);
@@ -1406,11 +1442,13 @@ static void sci_submit_rx(struct sci_port *s)
}
dev_dbg(s->port.dev, "%s(): cookie %d to #%d\n",
__func__, s->cookie_rx[i], i);
- }
- s->active_rx = s->cookie_rx[0];
+ if (i == 0) {
+ s->active_rx = s->cookie_rx[0];
+ dma_async_issue_pending(chan);
+ }
+ }
- dma_async_issue_pending(chan);
}
static void work_fn_rx(struct work_struct *work)
@@ -1419,11 +1457,19 @@ static void work_fn_rx(struct work_struct *work)
struct uart_port *port = &s->port;
struct dma_async_tx_descriptor *desc;
int new;
+ int next;
+
+ if (s->chan_rx == NULL) {
+ dev_dbg(port->dev, "%s: DMA channel is released.\n", __func__);
+ return;
+ }
if (s->active_rx == s->cookie_rx[0]) {
new = 0;
} else if (s->active_rx == s->cookie_rx[1]) {
new = 1;
+ } else if (s->active_rx == s->cookie_rx[2]) {
+ new = 2;
} else {
dev_err(port->dev, "cookie %d not found!\n", s->active_rx);
return;
@@ -1450,19 +1496,34 @@ static void work_fn_rx(struct work_struct *work)
if (count)
tty_flip_buffer_push(&port->state->port);
- sci_submit_rx(s);
+ if (!s->rx_release_flag)
+ sci_submit_rx(s);
+ s->rx_flag = 0;
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;
+ if (port->type == PORT_SCIF || port->type == PORT_HSCIF) {
+ if (new != 0) {
+ 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;
+ }
+ }
+ next = new % 2 + 1;
+ } else {
+ 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;
+ }
+ next = !new;
}
- s->active_rx = s->cookie_rx[!new];
+ s->active_rx = s->cookie_rx[next];
dev_dbg(port->dev, "%s: cookie %d #%d, new active #%d\n",
__func__, s->cookie_rx[new], new, s->active_rx);
@@ -1666,6 +1727,8 @@ static void sci_request_dma(struct uart_port *port)
if (s->cfg->dma_slave_tx <= 0 || s->cfg->dma_slave_rx <= 0)
return;
+ s->rx_flag = 0;
+ s->rx_release_flag = 0;
dma_cap_zero(mask);
dma_cap_set(DMA_SLAVE, mask);
@@ -1707,14 +1770,22 @@ static void sci_request_dma(struct uart_port *port)
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];
+ dma_addr_t dma[3];
+ void *buf[3];
+ size_t sum_buf_len;
+ int nr_sg = 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,
+ if (port->type == PORT_SCIF || port->type == PORT_HSCIF) {
+ nr_sg = 3;
+ sum_buf_len = 1 + s->buf_len_rx * 2;
+ } else {
+ sum_buf_len = s->buf_len_rx * 2;
+ }
+ buf[0] = dma_alloc_coherent(port->dev, sum_buf_len,
&dma[0], GFP_KERNEL);
if (!buf[0]) {
@@ -1724,14 +1795,28 @@ static void sci_request_dma(struct uart_port *port)
return;
}
- buf[1] = buf[0] + s->buf_len_rx;
- dma[1] = dma[0] + s->buf_len_rx;
+ if (port->type == PORT_SCIF || port->type == PORT_HSCIF) {
+ buf[1] = buf[0] + 1;
+ dma[1] = dma[0] + 1;
+ buf[2] = buf[1] + s->buf_len_rx;
+ dma[2] = dma[1] + s->buf_len_rx;
+ } else {
+ buf[1] = buf[0] + s->buf_len_rx;
+ dma[1] = dma[0] + s->buf_len_rx;
+ }
- for (i = 0; i < 2; i++) {
+ for (i = 0; i < nr_sg; i++) {
struct scatterlist *sg = &s->sg_rx[i];
+ unsigned int len;
+
+ if ((port->type == PORT_SCIF ||
+ port->type == PORT_HSCIF) && i == 0)
+ len = 1;
+ else
+ len = s->buf_len_rx;
sg_init_table(sg, 1);
- sg_set_page(sg, virt_to_page(buf[i]), s->buf_len_rx,
+ sg_set_page(sg, virt_to_page(buf[i]), len,
(uintptr_t)buf[i] & ~PAGE_MASK);
sg_dma_address(sg) = dma[i];
}
@@ -1778,7 +1863,6 @@ static int sci_startup(struct uart_port *port)
spin_lock_irqsave(&port->lock, flags);
sci_start_tx(port);
- sci_start_rx(port);
spin_unlock_irqrestore(&port->lock, flags);
return 0;
@@ -1796,6 +1880,8 @@ static void sci_shutdown(struct uart_port *port)
sci_stop_tx(port);
spin_unlock_irqrestore(&port->lock, flags);
+ serial_port_out(port, SCSCR, 0x00);
+
sci_free_dma(port);
sci_free_irq(s);
}
--
1.9.1
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