From: bigeasy@linutronix.de (Sebastian Andrzej Siewior)
To: linux-arm-kernel@lists.infradead.org
Subject: [PATCH 08/16] tty: serial: 8250_dma: enqueue RX dma again on completion.
Date: Wed, 10 Sep 2014 21:30:03 +0200 [thread overview]
Message-ID: <1410377411-26656-9-git-send-email-bigeasy@linutronix.de> (raw)
In-Reply-To: <1410377411-26656-1-git-send-email-bigeasy@linutronix.de>
The omap needs a DMA request pending right away. If it is enqueued once
the bytes are in the FIFO then nothing will happen and the FIFO will be
later purged via RX-timeout interrupt.
This patch enqueues RX-DMA request on completion but not if it was
aborted on error. The first enqueue will happen in the driver in
startup.
Reviewed-by: Tony Lindgren <tony@atomide.com>
Tested-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
---
drivers/tty/serial/8250/8250.h | 3 ++-
drivers/tty/serial/8250/8250_core.c | 3 +++
drivers/tty/serial/8250/8250_dma.c | 12 +++++++++---
3 files changed, 14 insertions(+), 4 deletions(-)
diff --git a/drivers/tty/serial/8250/8250.h b/drivers/tty/serial/8250/8250.h
index a63d198f8d03..fbed1636e9c4 100644
--- a/drivers/tty/serial/8250/8250.h
+++ b/drivers/tty/serial/8250/8250.h
@@ -80,7 +80,8 @@ struct serial8250_config {
#define UART_BUG_NOMSR (1 << 2) /* UART has buggy MSR status bits (Au1x00) */
#define UART_BUG_THRE (1 << 3) /* UART has buggy THRE reassertion */
#define UART_BUG_PARITY (1 << 4) /* UART mishandles parity if FIFO enabled */
-
+#define UART_BUG_DMA_RX (1 << 5) /* UART needs DMA RX req before there is
+ data in FIFO */
#define PROBE_RSA (1 << 0)
#define PROBE_ANY (~0)
diff --git a/drivers/tty/serial/8250/8250_core.c b/drivers/tty/serial/8250/8250_core.c
index 9f961ea82564..39b1c7318f17 100644
--- a/drivers/tty/serial/8250/8250_core.c
+++ b/drivers/tty/serial/8250/8250_core.c
@@ -1592,6 +1592,9 @@ int serial8250_handle_irq(struct uart_port *port, unsigned int iir)
if (!up->dma || dma_err)
status = serial8250_rx_chars(up, status);
+
+ if (dma_err && up->bugs & UART_BUG_DMA_RX)
+ serial8250_rx_dma(up, 0);
}
serial8250_modem_status(up);
if ((!up->dma || (up->dma && up->dma->tx_err)) &&
diff --git a/drivers/tty/serial/8250/8250_dma.c b/drivers/tty/serial/8250/8250_dma.c
index 69e54abb6e71..3674900a1f14 100644
--- a/drivers/tty/serial/8250/8250_dma.c
+++ b/drivers/tty/serial/8250/8250_dma.c
@@ -50,9 +50,8 @@ static void __dma_tx_complete(void *param)
spin_unlock_irqrestore(&p->port.lock, flags);
}
-static void __dma_rx_complete(void *param)
+static void __dma_rx_do_complete(struct uart_8250_port *p, bool error)
{
- struct uart_8250_port *p = param;
struct uart_8250_dma *dma = p->dma;
struct tty_port *tty_port = &p->port.state->port;
struct dma_tx_state state;
@@ -68,10 +67,17 @@ static void __dma_rx_complete(void *param)
tty_insert_flip_string(tty_port, dma->rx_buf, count);
p->port.icount.rx += count;
+ if (!error && p->bugs & UART_BUG_DMA_RX)
+ serial8250_rx_dma(p, 0);
tty_flip_buffer_push(tty_port);
}
+static void __dma_rx_complete(void *param)
+{
+ __dma_rx_do_complete(param, false);
+}
+
int serial8250_tx_dma(struct uart_8250_port *p)
{
struct uart_8250_dma *dma = p->dma;
@@ -139,7 +145,7 @@ int serial8250_rx_dma(struct uart_8250_port *p, unsigned int iir)
*/
if (dma_status == DMA_IN_PROGRESS) {
dmaengine_pause(dma->rxchan);
- __dma_rx_complete(p);
+ __dma_rx_do_complete(p, true);
}
return -ETIMEDOUT;
default:
--
2.1.0
next prev parent reply other threads:[~2014-09-10 19:30 UTC|newest]
Thread overview: 97+ messages / expand[flat|nested] mbox.gz Atom feed top
2014-09-10 19:29 [PATCH 00/16 v9] omap 8250 based uart + DMA Sebastian Andrzej Siewior
2014-09-10 19:29 ` [PATCH 01/16] tty: serial: 8250_core: allow to set ->throttle / ->unthrottle callbacks Sebastian Andrzej Siewior
2014-09-10 19:29 ` [PATCH 02/16] tty: serial: 8250_core: add run time pm Sebastian Andrzej Siewior
2014-09-29 9:46 ` Frans Klaver
2014-09-29 13:39 ` Sebastian Andrzej Siewior
2014-09-10 19:29 ` [PATCH 03/16] tty: serial: 8250_core: read only RX if there is something in the FIFO Sebastian Andrzej Siewior
2015-02-09 13:34 ` Nicolas Schichan
2015-02-09 23:34 ` Peter Hurley
2015-02-10 9:32 ` Sebastian Andrzej Siewior
2015-02-10 12:04 ` Nicolas Schichan
2015-02-10 17:46 ` Peter Hurley
2015-02-11 20:01 ` Peter Hurley
2015-02-11 20:03 ` Tony Lindgren
2015-02-11 20:42 ` Peter Hurley
2015-02-12 8:45 ` Sebastian Andrzej Siewior
2015-02-12 9:40 ` Russell King - ARM Linux
2015-02-12 16:32 ` Peter Hurley
2015-02-12 19:23 ` Sebastian Andrzej Siewior
2015-02-12 19:55 ` Peter Hurley
2015-02-12 20:34 ` Sebastian Andrzej Siewior
2015-02-13 18:51 ` Sebastian Andrzej Siewior
2015-02-13 23:15 ` Russell King - ARM Linux
2015-02-15 17:32 ` [PATCH] serial: 8250: Revert "tty: serial: 8250_core: read only RX if there is something in the FIFO" Sebastian Andrzej Siewior
2015-05-12 20:25 ` Tony Lindgren
2014-09-10 19:29 ` [PATCH 04/16] tty: serial: 8250_core: use the ->line argument as a hint in serial8250_find_match_or_unused() Sebastian Andrzej Siewior
2014-09-10 19:30 ` [PATCH 05/16] tty: serial: 8250_core: remove UART_IER_RDI in serial8250_stop_rx() Sebastian Andrzej Siewior
2014-09-11 11:19 ` Heikki Krogerus
2014-09-10 19:30 ` [PATCH 06/16] tty: serial: Add 8250-core based omap driver Sebastian Andrzej Siewior
2014-09-11 11:57 ` Peter Hurley
2014-09-16 17:01 ` Sebastian Andrzej Siewior
2014-09-29 9:38 ` Frans Klaver
2014-09-29 13:27 ` Sebastian Andrzej Siewior
2014-09-29 13:34 ` Frans Klaver
2014-09-10 19:30 ` [PATCH 07/16] tty: serial: 8250_dma: handle error on TX submit Sebastian Andrzej Siewior
2014-09-10 19:30 ` Sebastian Andrzej Siewior [this message]
2014-09-10 19:30 ` [PATCH 09/16] tty: serial: 8250_dma: Add a TX trigger workaround for AM33xx Sebastian Andrzej Siewior
2014-09-11 11:17 ` Heikki Krogerus
2014-09-11 11:42 ` Sebastian Andrzej Siewior
2014-09-11 12:32 ` Peter Hurley
2014-09-11 12:50 ` Sebastian Andrzej Siewior
2014-09-11 14:35 ` Peter Hurley
2014-09-15 17:01 ` Sebastian Andrzej Siewior
2014-09-16 16:55 ` Sebastian Andrzej Siewior
2014-09-17 12:20 ` Peter Hurley
2014-09-17 16:25 ` Sebastian Andrzej Siewior
2014-09-29 16:15 ` Sebastian Andrzej Siewior
2014-09-11 15:11 ` Frans Klaver
2014-09-11 16:04 ` Sebastian Andrzej Siewior
2014-09-11 17:04 ` Frans Klaver
2014-09-12 7:23 ` Sebastian Andrzej Siewior
[not found] ` <20140912094010.GE28458@ci00147.xsens-tech.local>
2014-09-12 9:51 ` Sebastian Andrzej Siewior
2014-09-12 10:28 ` Frans Klaver
2014-09-15 16:42 ` Sebastian Andrzej Siewior
2014-09-16 9:05 ` Frans Klaver
2014-09-16 12:42 ` Frans Klaver
2014-09-16 14:23 ` Frans Klaver
2014-09-17 10:28 ` Frans Klaver
2014-09-21 20:41 ` Sebastian Andrzej Siewior
2014-09-22 9:28 ` Frans Klaver
2014-09-24 7:56 ` Sebastian Andrzej Siewior
2014-09-25 15:14 ` Sebastian Andrzej Siewior
2014-09-25 15:18 ` Frans Klaver
2014-09-29 8:50 ` Frans Klaver
2014-09-29 9:54 ` Sebastian Andrzej Siewior
2014-09-29 10:30 ` Frans Klaver
2014-09-30 8:44 ` Frans Klaver
2014-10-02 10:27 ` Sebastian Andrzej Siewior
2014-10-13 14:55 ` Frans Klaver
2014-09-23 17:03 ` Peter Hurley
2014-09-24 7:53 ` Sebastian Andrzej Siewior
2014-09-25 10:42 ` Sebastian Andrzej Siewior
2014-09-25 11:31 ` Peter Hurley
2014-09-25 13:11 ` Sebastian Andrzej Siewior
2014-09-17 16:34 ` Sebastian Andrzej Siewior
2014-09-19 10:22 ` Heikki Krogerus
2014-09-19 10:58 ` Sebastian Andrzej Siewior
2014-09-19 11:25 ` Peter Hurley
2014-09-22 7:46 ` Heikki Krogerus
2014-09-25 9:24 ` Sebastian Andrzej Siewior
2014-09-10 19:30 ` [PATCH 10/16] tty: serial: 8250_dma: optimize the xmit path due to UART_BUG_DMA_TX Sebastian Andrzej Siewior
2014-09-10 19:30 ` [PATCH 11/16] tty: serial: 8250_dma: keep own book keeping about RX transfers Sebastian Andrzej Siewior
2014-09-10 19:30 ` [PATCH 12/16] tty: serial: 8250_dma: handle the UART RDI event while DMA remains idle Sebastian Andrzej Siewior
2014-09-29 9:23 ` Frans Klaver
2014-09-10 19:30 ` [PATCH 13/16] tty: serial: 8250_dma: add pm runtime Sebastian Andrzej Siewior
2014-09-29 9:26 ` Frans Klaver
2014-09-29 9:56 ` Sebastian Andrzej Siewior
2014-09-10 19:30 ` [PATCH 14/16] arm: dts: am33xx: add DMA properties for UART Sebastian Andrzej Siewior
2014-09-10 19:30 ` [PATCH 15/16] arm: dts: dra7: " Sebastian Andrzej Siewior
2014-09-10 19:30 ` [PATCH 16/16] tty: serial: 8250: omap: add dma support Sebastian Andrzej Siewior
2014-09-12 22:43 ` [PATCH 00/16 v9] omap 8250 based uart + DMA Tony Lindgren
2014-09-15 11:50 ` Sebastian Andrzej Siewior
2014-09-16 12:57 ` Sebastian Andrzej Siewior
2014-09-16 16:48 ` Tony Lindgren
2014-09-16 21:30 ` Tony Lindgren
2014-09-17 8:38 ` Sebastian Andrzej Siewior
2014-09-17 9:05 ` Sebastian Andrzej Siewior
2014-09-26 16:02 ` Greg KH
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=1410377411-26656-9-git-send-email-bigeasy@linutronix.de \
--to=bigeasy@linutronix.de \
--cc=linux-arm-kernel@lists.infradead.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).