Re: [PATCH v5 5/7] fpga: dfl: fme: add interrupt support for global error reporting

From: Marcelo Tosatti
Date: Mon May 25 2020 - 15:38:06 EST


On Mon, Apr 20, 2020 at 04:11:41PM +0800, Xu Yilun wrote:
> Error reporting interrupt is very useful to notify users that some
> errors are detected by the hardware. Once users are notified, they
> could query hardware logged error states, no need to continuously
> poll on these states.
>
> This patch adds interrupt support for fme global error reporting sub
> feature. It follows the common DFL interrupt notification and handling
> mechanism. And it implements two ioctls below for user to query
> number of irqs supported, and set/unset interrupt triggers.
>
> Ioctls:
> * DFL_FPGA_FME_ERR_GET_IRQ_NUM
> get the number of irqs, which is used to determine whether/how many
> interrupts fme error reporting feature supports.
>
> * DFL_FPGA_FME_ERR_SET_IRQ
> set/unset given eventfds as fme error reporting interrupt triggers.
>
> Signed-off-by: Luwei Kang <luwei.kang@xxxxxxxxx>
> Signed-off-by: Wu Hao <hao.wu@xxxxxxxxx>
> Signed-off-by: Xu Yilun <yilun.xu@xxxxxxxxx>
> Acked-by: Wu Hao <hao.wu@xxxxxxxxx>
> ----
> v2: use DFL_FPGA_FME_ERR_GET_IRQ_NUM instead of
> DFL_FPGA_FME_ERR_GET_INFO
> Delete flags field for DFL_FPGA_FME_ERR_SET_IRQ
> v3: put_user() instead of copy_to_user()
> improves comments
> v4: use common functions to handle irq ioctls
> v5: Minor fixes for Hao's comments
> ---
> drivers/fpga/dfl-fme-error.c | 18 ++++++++++++++++++
> drivers/fpga/dfl-fme-main.c | 6 ++++++
> include/uapi/linux/fpga-dfl.h | 23 +++++++++++++++++++++++
> 3 files changed, 47 insertions(+)
>
> diff --git a/drivers/fpga/dfl-fme-error.c b/drivers/fpga/dfl-fme-error.c
> index f897d41..51c2892 100644
> --- a/drivers/fpga/dfl-fme-error.c
> +++ b/drivers/fpga/dfl-fme-error.c
> @@ -15,6 +15,7 @@
> * Mitchel, Henry <henry.mitchel@xxxxxxxxx>
> */
>
> +#include <linux/fpga-dfl.h>
> #include <linux/uaccess.h>
>
> #include "dfl.h"
> @@ -348,6 +349,22 @@ static void fme_global_err_uinit(struct platform_device *pdev,
> fme_err_mask(&pdev->dev, true);
> }
>
> +static long
> +fme_global_error_ioctl(struct platform_device *pdev,
> + struct dfl_feature *feature,
> + unsigned int cmd, unsigned long arg)
> +{
> + switch (cmd) {
> + case DFL_FPGA_FME_ERR_GET_IRQ_NUM:
> + return dfl_feature_ioctl_get_num_irqs(pdev, feature, arg);
> + case DFL_FPGA_FME_ERR_SET_IRQ:
> + return dfl_feature_ioctl_set_irq(pdev, feature, arg);
> + default:
> + dev_dbg(&pdev->dev, "%x cmd not handled", cmd);
> + return -ENODEV;
> + }
> +}
> +
> const struct dfl_feature_id fme_global_err_id_table[] = {
> {.id = FME_FEATURE_ID_GLOBAL_ERR,},
> {0,}
> @@ -356,4 +373,5 @@ const struct dfl_feature_id fme_global_err_id_table[] = {
> const struct dfl_feature_ops fme_global_err_ops = {
> .init = fme_global_err_init,
> .uinit = fme_global_err_uinit,
> + .ioctl = fme_global_error_ioctl,
> };
> diff --git a/drivers/fpga/dfl-fme-main.c b/drivers/fpga/dfl-fme-main.c
> index 56d720c..ab3722d 100644
> --- a/drivers/fpga/dfl-fme-main.c
> +++ b/drivers/fpga/dfl-fme-main.c
> @@ -616,11 +616,17 @@ static int fme_release(struct inode *inode, struct file *filp)
> {
> struct dfl_feature_platform_data *pdata = filp->private_data;
> struct platform_device *pdev = pdata->dev;
> + struct dfl_feature *feature;
>
> dev_dbg(&pdev->dev, "Device File Release\n");
>
> mutex_lock(&pdata->lock);
> dfl_feature_dev_use_end(pdata);
> +
> + if (!dfl_feature_dev_use_count(pdata))
> + dfl_fpga_dev_for_each_feature(pdata, feature)
> + dfl_fpga_set_irq_triggers(feature, 0,
> + feature->nr_irqs, NULL);
> mutex_unlock(&pdata->lock);
>
> return 0;
> diff --git a/include/uapi/linux/fpga-dfl.h b/include/uapi/linux/fpga-dfl.h
> index 6c71c9d..b6495ea 100644
> --- a/include/uapi/linux/fpga-dfl.h
> +++ b/include/uapi/linux/fpga-dfl.h
> @@ -230,4 +230,27 @@ struct dfl_fpga_fme_port_pr {
> */
> #define DFL_FPGA_FME_PORT_ASSIGN _IOW(DFL_FPGA_MAGIC, DFL_FME_BASE + 2, int)
>
> +/**
> + * DFL_FPGA_FME_ERR_GET_IRQ_NUM - _IOR(DFL_FPGA_MAGIC, DFL_FME_BASE + 3,
> + * __u32 num_irqs)
> + *
> + * Get the number of irqs supported by the fpga fme error reporting private
> + * feature. Currently hardware supports up to 1 irq.
> + * Return: 0 on success, -errno on failure.
> + */
> +#define DFL_FPGA_FME_ERR_GET_IRQ_NUM _IOR(DFL_FPGA_MAGIC, \
> + DFL_FME_BASE + 3, __u32)
> +
> +/**
> + * DFL_FPGA_FME_ERR_SET_IRQ - _IOW(DFL_FPGA_MAGIC, DFL_FME_BASE + 4,
> + * struct dfl_fpga_irq_set)
> + *
> + * Set fpga fme error reporting interrupt trigger if evtfds[n] is valid.
> + * Unset related interrupt trigger if evtfds[n] is a negative value.
> + * Return: 0 on success, -errno on failure.
> + */
> +#define DFL_FPGA_FME_ERR_SET_IRQ _IOW(DFL_FPGA_MAGIC, \
> + DFL_FME_BASE + 4, \
> + struct dfl_fpga_irq_set)
> +
> #endif /* _UAPI_LINUX_FPGA_DFL_H */
> --
> 2.7.4

Reviewed-by: Marcelo Tosatti <mtosatti@xxxxxxxxxx>