[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-ID: <1450364294.30729.134.camel@linux.intel.com>
Date: Thu, 17 Dec 2015 16:58:14 +0200
From: Andy Shevchenko <andriy.shevchenko@...ux.intel.com>
To: Mans Rullgard <mans@...sr.com>, Tejun Heo <tj@...nel.org>,
linux-ide@...r.kernel.org, linux-kernel@...r.kernel.org
Subject: Re: [PATCH 1/3] ata: sata_dwc_460ex: use "dmas" DT property to find
dma channel
On Tue, 2015-12-15 at 23:25 +0000, Mans Rullgard wrote:
> Currently this driver only works with a DesignWare DMA engine which
> it
> registers manually using the second "reg" address range and interrupt
> number from the DT node.
>
> This patch makes the driver instead use the "dmas" property if
> present,
> otherwise optionally falling back on the old way so existing device
> trees can continue to work.
>
> With this change, there is no longer any reason to depend on the
> 460EX
> machine type so drop that from Kconfig.
Looks good for me (from dw_dmac usage prospective).
>
> Signed-off-by: Mans Rullgard <mans@...sr.com>
> ---
> drivers/ata/Kconfig | 10 ++-
> drivers/ata/sata_dwc_460ex.c | 192 +++++++++++++++++++++++++++----
> ------------
> 2 files changed, 131 insertions(+), 71 deletions(-)
>
> diff --git a/drivers/ata/Kconfig b/drivers/ata/Kconfig
> index 3fc2a56..193c673 100644
> --- a/drivers/ata/Kconfig
> +++ b/drivers/ata/Kconfig
> @@ -296,14 +296,20 @@ config ATA_PIIX
>
> config SATA_DWC
> tristate "DesignWare Cores SATA support"
> - depends on 460EX
> - select DW_DMAC
> help
> This option enables support for the on-chip SATA
> controller of the
> AppliedMicro processor 460EX.
>
> If unsure, say N.
>
> +config SATA_DWC_OLD_DMA
> + bool "Support old device trees"
> + depends on SATA_DWC && 460EX
> + select DW_DMAC
> + help
> + This option enables support for old device trees without
> the
> + "dmas" property.
> +
> config SATA_DWC_DEBUG
> bool "Debugging driver version"
> depends on SATA_DWC
> diff --git a/drivers/ata/sata_dwc_460ex.c
> b/drivers/ata/sata_dwc_460ex.c
> index 9020349..9985749 100644
> --- a/drivers/ata/sata_dwc_460ex.c
> +++ b/drivers/ata/sata_dwc_460ex.c
> @@ -30,6 +30,7 @@
> #include <linux/kernel.h>
> #include <linux/module.h>
> #include <linux/device.h>
> +#include <linux/dmaengine.h>
> #include <linux/of_address.h>
> #include <linux/of_irq.h>
> #include <linux/of_platform.h>
> @@ -42,10 +43,6 @@
> #include <scsi/scsi_host.h>
> #include <scsi/scsi_cmnd.h>
>
> -/* Supported DMA engine drivers */
> -#include <linux/platform_data/dma-dw.h>
> -#include <linux/dma/dw.h>
> -
> /* These two are defined in "libata.h" */
> #undef DRV_NAME
> #undef DRV_VERSION
> @@ -148,7 +145,9 @@ struct sata_dwc_device {
> struct ata_host *host;
> u8 __iomem *reg_base;
> struct sata_dwc_regs *sata_dwc_regs; /* DW
> Synopsys SATA specific */
> +#ifdef CONFIG_SATA_DWC_OLD_DMA
> struct dw_dma_chip *dma;
> +#endif
> };
>
> #define SATA_DWC_QCMD_MAX 32
> @@ -159,7 +158,6 @@ struct sata_dwc_device_port {
> int dma_pending[SATA_DWC_QCMD_MAX];
>
> /* DMA info */
> - struct dw_dma_slave *dws;
> struct dma_chan *chan;
> struct dma_async_tx_descriptor *desc[SATA_DWC_QCMD_MA
> X];
> u32 dma_interrupt_count;
> @@ -198,13 +196,6 @@ struct sata_dwc_host_priv {
>
> static struct sata_dwc_host_priv host_pvt;
>
> -static struct dw_dma_slave sata_dwc_dma_dws = {
> - .src_id = 0,
> - .dst_id = 0,
> - .src_master = 0,
> - .dst_master = 1,
> -};
> -
> /*
> * Prototypes
> */
> @@ -215,6 +206,90 @@ static void sata_dwc_dma_xfer_complete(struct
> ata_port *ap, u32 check_status);
> static void sata_dwc_port_stop(struct ata_port *ap);
> static void sata_dwc_clear_dmacr(struct sata_dwc_device_port
> *hsdevp, u8 tag);
>
> +#ifdef CONFIG_SATA_DWC_OLD_DMA
> +
> +#include <linux/platform_data/dma-dw.h>
> +#include <linux/dma/dw.h>
> +
> +static struct dw_dma_slave sata_dwc_dma_dws = {
> + .src_id = 0,
> + .dst_id = 0,
> + .src_master = 0,
> + .dst_master = 1,
> +};
> +
> +static bool sata_dwc_dma_filter(struct dma_chan *chan, void *param)
> +{
> + struct dw_dma_slave *dws = &sata_dwc_dma_dws;
> +
> + if (dws->dma_dev != chan->device->dev)
> + return false;
> +
> + chan->private = dws;
> + return true;
> +}
> +
> +static int sata_dwc_dma_get_channel_old(struct sata_dwc_device_port
> *hsdevp)
> +{
> + struct sata_dwc_device *hsdev = hsdevp->hsdev;
> + struct dw_dma_slave *dws = &sata_dwc_dma_dws;
> + dma_cap_mask_t mask;
> +
> + dws->dma_dev = hsdev->dev;
> +
> + dma_cap_zero(mask);
> + dma_cap_set(DMA_SLAVE, mask);
> +
> + /* Acquire DMA channel */
> + hsdevp->chan = dma_request_channel(mask,
> sata_dwc_dma_filter, hsdevp);
> + if (!hsdevp->chan) {
> + dev_err(hsdev->dev, "%s: dma channel unavailable\n",
> + __func__);
> + return -EAGAIN;
> + }
> +
> + return 0;
> +}
> +
> +static int sata_dwc_dma_init_old(struct platform_device *pdev,
> + struct sata_dwc_device *hsdev)
> +{
> + struct device_node *np = pdev->dev.of_node;
> + int err;
> +
> + hsdev->dma = devm_kzalloc(&pdev->dev, sizeof(*hsdev->dma),
> GFP_KERNEL);
> + if (!hsdev->dma)
> + return -ENOMEM;
> +
> + hsdev->dma->dev = &pdev->dev;
> +
> + /* Get SATA DMA interrupt number */
> + hsdev->dma->irq = irq_of_parse_and_map(np, 1);
> + if (hsdev->dma->irq == NO_IRQ) {
> + dev_err(&pdev->dev, "no SATA DMA irq\n");
> + return -ENODEV;
> + }
> +
> + /* Get physical SATA DMA register base address */
> + hsdev->dma->regs = of_iomap(np, 1);
> + if (!hsdev->dma->regs) {
> + dev_err(&pdev->dev,
> + "ioremap failed for AHBDMA register
> address\n");
> + return -ENODEV;
> + }
> +
> + /* Initialize AHB DMAC */
> + err = dw_dma_probe(hsdev->dma, NULL);
> + if (err) {
> + iounmap(hsdev->dma->regs);
> + return err;
> + }
> +
> + return 0;
> +}
> +
> +#endif
> +
> static const char *get_prot_descript(u8 protocol)
> {
> switch ((enum ata_tf_protocols)protocol) {
> @@ -783,18 +858,6 @@ static void sata_dwc_enable_interrupts(struct
> sata_dwc_device *hsdev)
> in_le32(&hsdev->sata_dwc_regs->errmr));
> }
>
> -static bool sata_dwc_dma_filter(struct dma_chan *chan, void *param)
> -{
> - struct sata_dwc_device_port *hsdevp = param;
> - struct dw_dma_slave *dws = hsdevp->dws;
> -
> - if (dws->dma_dev != chan->device->dev)
> - return false;
> -
> - chan->private = dws;
> - return true;
> -}
> -
> static void sata_dwc_setup_port(struct ata_ioports *port, unsigned
> long base)
> {
> port->cmd_addr = (void __iomem *)base + 0x00;
> @@ -817,6 +880,26 @@ static void sata_dwc_setup_port(struct
> ata_ioports *port, unsigned long base)
> port->ctl_addr = (void __iomem *)base + 0x20;
> }
>
> +static int sata_dwc_dma_get_channel(struct sata_dwc_device_port
> *hsdevp)
> +{
> + struct sata_dwc_device *hsdev = hsdevp->hsdev;
> + struct device *dev = hsdev->dev;
> +
> +#ifdef CONFIG_SATA_DWC_OLD_DMA
> + if (!of_find_property(dev->of_node, "dmas", NULL))
> + return sata_dwc_dma_get_channel_old(hsdevp);
> +#endif
> +
> + hsdevp->chan = dma_request_slave_channel(dev, "sata-dma");
> + if (IS_ERR(hsdevp->chan)) {
> + dev_err(dev, "failed to allocate dma channel:
> %ld\n",
> + PTR_ERR(hsdevp->chan));
> + return PTR_ERR(hsdevp->chan);
> + }
> +
> + return 0;
> +}
> +
> /*
> * Function : sata_dwc_port_start
> * arguments : struct ata_ioports *port
> @@ -829,7 +912,6 @@ static int sata_dwc_port_start(struct ata_port
> *ap)
> struct sata_dwc_device *hsdev;
> struct sata_dwc_device_port *hsdevp = NULL;
> struct device *pdev;
> - dma_cap_mask_t mask;
> int i;
>
> hsdev = HSDEV_FROM_AP(ap);
> @@ -853,20 +935,9 @@ static int sata_dwc_port_start(struct ata_port
> *ap)
> }
> hsdevp->hsdev = hsdev;
>
> - hsdevp->dws = &sata_dwc_dma_dws;
> - hsdevp->dws->dma_dev = hsdev->dev;
> -
> - dma_cap_zero(mask);
> - dma_cap_set(DMA_SLAVE, mask);
> -
> - /* Acquire DMA channel */
> - hsdevp->chan = dma_request_channel(mask,
> sata_dwc_dma_filter, hsdevp);
> - if (!hsdevp->chan) {
> - dev_err(hsdev->dev, "%s: dma channel unavailable\n",
> - __func__);
> - err = -EAGAIN;
> + err = sata_dwc_dma_get_channel(hsdevp);
> + if (err)
> goto CLEANUP_ALLOC;
> - }
>
> for (i = 0; i < SATA_DWC_QCMD_MAX; i++)
> hsdevp->cmd_issued[i] = SATA_DWC_CMD_ISSUED_NOT;
> @@ -1225,33 +1296,9 @@ static int sata_dwc_probe(struct
> platform_device *ofdev)
> dev_notice(&ofdev->dev, "id %d, controller version
> %c.%c%c\n",
> idr, ver[0], ver[1], ver[2]);
>
> - /* Get SATA DMA interrupt number */
> - hsdev->dma->irq = irq_of_parse_and_map(np, 1);
> - if (hsdev->dma->irq == NO_IRQ) {
> - dev_err(&ofdev->dev, "no SATA DMA irq\n");
> - err = -ENODEV;
> - goto error_iomap;
> - }
> -
> - /* Get physical SATA DMA register base address */
> - hsdev->dma->regs = of_iomap(np, 1);
> - if (!hsdev->dma->regs) {
> - dev_err(&ofdev->dev,
> - "ioremap failed for AHBDMA register
> address\n");
> - err = -ENODEV;
> - goto error_iomap;
> - }
> -
> /* Save dev for later use in dev_xxx() routines */
> hsdev->dev = &ofdev->dev;
>
> - hsdev->dma->dev = &ofdev->dev;
> -
> - /* Initialize AHB DMAC */
> - err = dw_dma_probe(hsdev->dma, NULL);
> - if (err)
> - goto error_dma_iomap;
> -
> /* Enable SATA Interrupts */
> sata_dwc_enable_interrupts(hsdev);
>
> @@ -1263,6 +1310,14 @@ static int sata_dwc_probe(struct
> platform_device *ofdev)
> goto error_out;
> }
>
> +#ifdef CONFIG_SATA_DWC_OLD_DMA
> + if (!of_find_property(np, "dmas", NULL)) {
> + err = sata_dwc_dma_init_old(ofdev, hsdev);
> + if (err)
> + goto error_out;
> + }
> +#endif
> +
> /*
> * Now, register with libATA core, this will also initiate
> the
> * device discovery process, invoking our port_start()
> handler &
> @@ -1276,11 +1331,6 @@ static int sata_dwc_probe(struct
> platform_device *ofdev)
> return 0;
>
> error_out:
> - /* Free SATA DMA resources */
> - dw_dma_remove(hsdev->dma);
> -error_dma_iomap:
> - iounmap(hsdev->dma->regs);
> -error_iomap:
> iounmap(base);
> return err;
> }
> @@ -1293,10 +1343,14 @@ static int sata_dwc_remove(struct
> platform_device *ofdev)
>
> ata_host_detach(host);
>
> +#ifdef CONFIG_SATA_DWC_OLD_DMA
> /* Free SATA DMA resources */
> - dw_dma_remove(hsdev->dma);
> + if (hsdev->dma) {
> + dw_dma_remove(hsdev->dma);
> + iounmap(hsdev->dma->regs);
> + }
> +#endif
>
> - iounmap(hsdev->dma->regs);
> iounmap(hsdev->reg_base);
> dev_dbg(&ofdev->dev, "done\n");
> return 0;
--
Andy Shevchenko <andriy.shevchenko@...ux.intel.com>
Intel Finland Oy
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
Powered by blists - more mailing lists