linux-kernel.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
To: "Bryan O'Donoghue" <pure.logic@nexus-software.ie>,
	Peter Hurley <peter@hurleysoftware.com>,
	linux-serial@vger.kernel.org, Vinod Koul <vinod.koul@intel.com>,
	linux-kernel@vger.kernel.org, dmaengine@vger.kernel.org,
	Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
	ismo.puustinen@intel.com,
	Heikki Krogerus <heikki.krogerus@linux.intel.com>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Subject: [PATCH v9 11/11] serial: 8250_lpss: enable DMA on Intel Quark UART
Date: Mon, 20 Jun 2016 12:18:02 +0300	[thread overview]
Message-ID: <1466414282-96691-12-git-send-email-andriy.shevchenko@linux.intel.com> (raw)
In-Reply-To: <1466414282-96691-1-git-send-email-andriy.shevchenko@linux.intel.com>

DMA on Intel Quark SoC is a part of UART IP block. Enable it.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
---
 drivers/tty/serial/8250/8250_lpss.c | 83 +++++++++++++++++++++++++++++++++++--
 1 file changed, 79 insertions(+), 4 deletions(-)

diff --git a/drivers/tty/serial/8250/8250_lpss.c b/drivers/tty/serial/8250/8250_lpss.c
index 5ac291c..14f3256 100644
--- a/drivers/tty/serial/8250/8250_lpss.c
+++ b/drivers/tty/serial/8250/8250_lpss.c
@@ -15,7 +15,7 @@
 #include <linux/rational.h>
 
 #include <linux/dmaengine.h>
-#include <linux/platform_data/dma-dw.h>
+#include <linux/dma/dw.h>
 
 #include "8250.h"
 
@@ -47,6 +47,7 @@ struct lpss8250_board {
 	unsigned long freq;
 	unsigned int base_baud;
 	int (*setup)(struct lpss8250 *, struct uart_port *p);
+	void (*exit)(struct lpss8250 *);
 };
 
 struct lpss8250 {
@@ -55,6 +56,7 @@ struct lpss8250 {
 
 	/* DMA parameters */
 	struct uart_8250_dma dma;
+	struct dw_dma_chip dma_chip;
 	struct dw_dma_slave dma_param;
 	u8 dma_maxburst;
 };
@@ -151,6 +153,65 @@ static int byt_serial_setup(struct lpss8250 *lpss, struct uart_port *port)
 	return 0;
 }
 
+#ifdef CONFIG_SERIAL_8250_DMA
+static const struct dw_dma_platform_data qrk_serial_dma_pdata = {
+	.nr_channels = 2,
+	.is_private = true,
+	.is_nollp = true,
+	.chan_allocation_order = CHAN_ALLOCATION_ASCENDING,
+	.chan_priority = CHAN_PRIORITY_ASCENDING,
+	.block_size = 4095,
+	.nr_masters = 1,
+	.data_width = {4},
+};
+
+static int qrk_serial_setup_dma(struct lpss8250 *lpss, struct uart_port *port)
+{
+	struct uart_8250_dma *dma = &lpss->dma;
+	struct dw_dma_chip *chip = &lpss->dma_chip;
+	struct dw_dma_slave *param = &lpss->dma_param;
+	struct pci_dev *pdev = to_pci_dev(port->dev);
+	int ret;
+
+	chip->dev = &pdev->dev;
+	chip->irq = pdev->irq;
+	chip->regs = pci_ioremap_bar(pdev, 1);
+	chip->pdata = &qrk_serial_dma_pdata;
+
+	/* Falling back to PIO mode if DMA probing fails */
+	ret = dw_dma_probe(chip);
+	if (ret)
+		return 0;
+
+	/* Special DMA address for UART */
+	dma->rx_dma_addr = 0xfffff000;
+	dma->tx_dma_addr = 0xfffff000;
+
+	param->dma_dev = &pdev->dev;
+	param->src_id = 0;
+	param->dst_id = 1;
+	param->hs_polarity = true;
+
+	lpss->dma_maxburst = 8;
+	return 0;
+}
+
+static void qrk_serial_exit_dma(struct lpss8250 *lpss)
+{
+	struct dw_dma_slave *param = &lpss->dma_param;
+
+	if (!param->dma_dev)
+		return;
+	dw_dma_remove(&lpss->dma_chip);
+}
+#else	/* CONFIG_SERIAL_8250_DMA */
+static int qrk_serial_setup_dma(struct lpss8250 *lpss, struct uart_port *port)
+{
+	return 0;
+}
+static void qrk_serial_exit_dma(struct lpss8250 *lpss) {}
+#endif	/* !CONFIG_SERIAL_8250_DMA */
+
 static int qrk_serial_setup(struct lpss8250 *lpss, struct uart_port *port)
 {
 	struct pci_dev *pdev = to_pci_dev(port->dev);
@@ -159,7 +220,12 @@ static int qrk_serial_setup(struct lpss8250 *lpss, struct uart_port *port)
 
 	port->irq = pdev->irq;
 
-	return 0;
+	return qrk_serial_setup_dma(lpss, port);
+}
+
+static void qrk_serial_exit(struct lpss8250 *lpss)
+{
+	qrk_serial_exit_dma(lpss);
 }
 
 static bool lpss8250_dma_filter(struct dma_chan *chan, void *param)
@@ -244,22 +310,30 @@ static int lpss8250_probe(struct pci_dev *pdev, const struct pci_device_id *id)
 
 	ret = lpss8250_dma_setup(lpss, &uart);
 	if (ret)
-		return ret;
+		goto err_exit;
 
 	ret = serial8250_register_8250_port(&uart);
 	if (ret < 0)
-		return ret;
+		goto err_exit;
 
 	lpss->line = ret;
 
 	pci_set_drvdata(pdev, lpss);
 	return 0;
+
+err_exit:
+	if (lpss->board->exit)
+		lpss->board->exit(lpss);
+	return ret;
 }
 
 static void lpss8250_remove(struct pci_dev *pdev)
 {
 	struct lpss8250 *lpss = pci_get_drvdata(pdev);
 
+	if (lpss->board->exit)
+		lpss->board->exit(lpss);
+
 	serial8250_unregister_port(lpss->line);
 }
 
@@ -273,6 +347,7 @@ static const struct lpss8250_board qrk_board = {
 	.freq = 44236800,
 	.base_baud = 2764800,
 	.setup = qrk_serial_setup,
+	.exit = qrk_serial_exit,
 };
 
 #define LPSS_DEVICE(id, board) { PCI_VDEVICE(INTEL, id), (kernel_ulong_t)&board }
-- 
2.8.1

  parent reply	other threads:[~2016-06-20  9:18 UTC|newest]

Thread overview: 15+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2016-06-20  9:17 [PATCH v9 00/11] serial: 8250: split LPSS to 8250_lpss, enable DMA on Quark Andy Shevchenko
2016-06-20  9:17 ` [PATCH v9 01/11] dmaengine: dw: keep copy of custom slave config in dwc Andy Shevchenko
2016-06-20  9:17 ` [PATCH v9 02/11] dmaengine: dw: provide probe(), remove() stubs for users Andy Shevchenko
2016-06-20  9:17 ` [PATCH v9 03/11] dmaengine: dw: set polarity of handshake interface Andy Shevchenko
2016-06-20  9:17 ` [PATCH v9 04/11] dmaengine: dw: override LLP support if asked in platform data Andy Shevchenko
2016-06-20  9:17 ` [PATCH v9 05/11] serial: 8250_dma: switch to new dmaengine_terminate_* API Andy Shevchenko
2016-06-20  9:17 ` [PATCH v9 06/11] serial: 8250_dma: adjust DMA address of the UART Andy Shevchenko
2016-06-20  9:17 ` [PATCH v9 07/11] serial: 8250: enable AFE on ports where FIFO is 16 bytes Andy Shevchenko
2016-06-20  9:17 ` [PATCH v9 08/11] serial: 8250_lpss: split LPSS driver to separate module Andy Shevchenko
2016-06-20  9:18 ` [PATCH v9 09/11] serial: 8250_lpss: move Quark code from PCI driver Andy Shevchenko
2016-06-20  9:18 ` [PATCH v9 10/11] serial: 8250_lpss: enable MSI for Intel Quark Andy Shevchenko
2016-06-20  9:18 ` Andy Shevchenko [this message]
2016-06-21 15:10 ` [PATCH v9 00/11] serial: 8250: split LPSS to 8250_lpss, enable DMA on Quark Bryan O'Donoghue
2016-06-21 15:46   ` Andy Shevchenko
2016-08-03 16:14   ` Andy Shevchenko

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=1466414282-96691-12-git-send-email-andriy.shevchenko@linux.intel.com \
    --to=andriy.shevchenko@linux.intel.com \
    --cc=dmaengine@vger.kernel.org \
    --cc=gregkh@linuxfoundation.org \
    --cc=heikki.krogerus@linux.intel.com \
    --cc=ismo.puustinen@intel.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-serial@vger.kernel.org \
    --cc=peter@hurleysoftware.com \
    --cc=pure.logic@nexus-software.ie \
    --cc=vinod.koul@intel.com \
    /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).