On 9/17/20 11:32 AM, Russ Weight wrote:
> Port enable is not complete until ACK = 0. Change
> __afu_port_enable() to guarantee that the enable process
> is complete by polling for ACK == 0.
>
> Signed-off-by: Russ Weight <russell.h.wei...@intel.com>
> ---
> drivers/fpga/dfl-afu-error.c | 2 +-
> drivers/fpga/dfl-afu-main.c | 29 +++++++++++++++++++++--------
> drivers/fpga/dfl-afu.h | 2 +-
> 3 files changed, 23 insertions(+), 10 deletions(-)
>
> diff --git a/drivers/fpga/dfl-afu-error.c b/drivers/fpga/dfl-afu-error.c
> index c4691187cca9..0806532a3e9f 100644
> --- a/drivers/fpga/dfl-afu-error.c
> +++ b/drivers/fpga/dfl-afu-error.c
> @@ -103,7 +103,7 @@ static int afu_port_err_clear(struct device *dev, u64 err)
> __afu_port_err_mask(dev, false);
>
There is an earlier bit that sets ret = -EINVAL.
This error will be lost or not handled well.
Right now it doesn't seem to be handled.
> /* Enable the Port by clear the reset */
> - __afu_port_enable(pdev);
> + ret = __afu_port_enable(pdev);
>
> done:
> mutex_unlock(&pdata->lock);
> diff --git a/drivers/fpga/dfl-afu-main.c b/drivers/fpga/dfl-afu-main.c
> index 753cda4b2568..f73b06cdf13c 100644
> --- a/drivers/fpga/dfl-afu-main.c
> +++ b/drivers/fpga/dfl-afu-main.c
> @@ -21,6 +21,9 @@
>
> #include "dfl-afu.h"
>
> +#define RST_POLL_INVL 10 /* us */
> +#define RST_POLL_TIMEOUT 1000 /* us */
> +
> /**
> * __afu_port_enable - enable a port by clear reset
> * @pdev: port platform device.
> @@ -32,7 +35,7 @@
> *
> * The caller needs to hold lock for protection.
> */
> -void __afu_port_enable(struct platform_device *pdev)
> +int __afu_port_enable(struct platform_device *pdev)
> {
> struct dfl_feature_platform_data *pdata = dev_get_platdata(&pdev->dev);
> void __iomem *base;
> @@ -41,7 +44,7 @@ void __afu_port_enable(struct platform_device *pdev)
> WARN_ON(!pdata->disable_count);
>
> if (--pdata->disable_count != 0)
> - return;
> + return 0;
Is this really a success ? Maybe -EBUSY ?
>
> base = dfl_get_feature_ioaddr_by_id(&pdev->dev, PORT_FEATURE_ID_HEADER);
>
> @@ -49,10 +52,20 @@ void __afu_port_enable(struct platform_device *pdev)
> v = readq(base + PORT_HDR_CTRL);
> v &= ~PORT_CTRL_SFTRST;
> writeq(v, base + PORT_HDR_CTRL);
> -}
>
> -#define RST_POLL_INVL 10 /* us */
> -#define RST_POLL_TIMEOUT 1000 /* us */
> + /*
> + * HW clears the ack bit to indicate that the port is fully out
> + * of reset.
> + */
> + if (readq_poll_timeout(base + PORT_HDR_CTRL, v,
> + !(v & PORT_CTRL_SFTRST_ACK),
> + RST_POLL_INVL, RST_POLL_TIMEOUT)) {
> + dev_err(&pdev->dev, "timeout, failure to enable device\n");
> + return -ETIMEDOUT;
> + }
> +
> + return 0;
> +}
>
> /**
> * __afu_port_disable - disable a port by hold reset
> @@ -111,7 +124,7 @@ static int __port_reset(struct platform_device *pdev)
>
> ret = __afu_port_disable(pdev);
> if (!ret)
> - __afu_port_enable(pdev);
> + ret = __afu_port_enable(pdev);
>
> return ret;
> }
> @@ -872,11 +885,11 @@ static int afu_dev_destroy(struct platform_device *pdev)
> static int port_enable_set(struct platform_device *pdev, bool enable)
> {
> struct dfl_feature_platform_data *pdata = dev_get_platdata(&pdev->dev);
> - int ret = 0;
> + int ret;
>
> mutex_lock(&pdata->lock);
> if (enable)
> - __afu_port_enable(pdev);
> + ret = __afu_port_enable(pdev);
> else
> ret = __afu_port_disable(pdev);
> mutex_unlock(&pdata->lock);
> diff --git a/drivers/fpga/dfl-afu.h b/drivers/fpga/dfl-afu.h
> index 576e94960086..e5020e2b1f3d 100644
> --- a/drivers/fpga/dfl-afu.h
> +++ b/drivers/fpga/dfl-afu.h
> @@ -80,7 +80,7 @@ struct dfl_afu {
> };
>
> /* hold pdata->lock when call __afu_port_enable/disable */
> -void __afu_port_enable(struct platform_device *pdev);
> +int __afu_port_enable(struct platform_device *pdev);
> int __afu_port_disable(struct platform_device *pdev);
The other functions in this file have afu_* since the __afu_port_enable/disable
are used other places would it make sense to remove the '__' prefix ?
If you think so, maybe a cleanup patch later.
Tom
>
> void afu_mmio_region_init(struct dfl_feature_platform_data *pdata);
