Re: [PATCH v5 4/7] fpga: dfl: afu: add interrupt support for port error reporting

Marcelo Tosatti
2020-05-25T19:38:10Z

On Mon, Apr 20, 2020 at 04:11:40PM +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 port error reporting sub feature.
> It follows the common DFL interrupt notification and handling mechanism,
> implements two ioctl commands below for user to query number of irqs
> supported, and set/unset interrupt triggers.
>
> Ioctls:
> * DFL_FPGA_PORT_ERR_GET_IRQ_NUM
> get the number of irqs, which is used to determine whether/how many
> interrupts error reporting feature supports.
>
> * DFL_FPGA_PORT_ERR_SET_IRQ
> set/unset given eventfds as error interrupt triggers.
>
> Signed-off-by: Luwei Kang <luwei.kang@intel.com>
> Signed-off-by: Wu Hao <hao.wu@intel.com>
> Signed-off-by: Xu Yilun <yilun.xu@intel.com>
> Acked-by: Wu Hao <hao.wu@intel.com>
> ----
> v2: use DFL_FPGA_PORT_ERR_GET_IRQ_NUM instead of
> DFL_FPGA_PORT_ERR_GET_INFO
> Delete flag field for DFL_FPGA_PORT_ERR_SET_IRQ param
> 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-afu-error.c | 17 +++++++++++++++++
> drivers/fpga/dfl-afu-main.c | 4 ++++
> include/uapi/linux/fpga-dfl.h | 23 +++++++++++++++++++++++
> 3 files changed, 44 insertions(+)
>
> diff --git a/drivers/fpga/dfl-afu-error.c b/drivers/fpga/dfl-afu-error.c
> index c1467ae..c469118 100644
> --- a/drivers/fpga/dfl-afu-error.c
> +++ b/drivers/fpga/dfl-afu-error.c
> @@ -14,6 +14,7 @@
> * Mitchel Henry <henry.mitchel@intel.com>
> */
>
> +#include <linux/fpga-dfl.h>
> #include <linux/uaccess.h>
>
> #include "dfl-afu.h"
> @@ -219,6 +220,21 @@ static void port_err_uinit(struct platform_device *pdev,
> afu_port_err_mask(&pdev->dev, true);
> }
>
> +static long
> +port_err_ioctl(struct platform_device *pdev, struct dfl_feature *feature,
> + unsigned int cmd, unsigned long arg)
> +{
> + switch (cmd) {
> + case DFL_FPGA_PORT_ERR_GET_IRQ_NUM:
> + return dfl_feature_ioctl_get_num_irqs(pdev, feature, arg);
> + case DFL_FPGA_PORT_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 port_err_id_table[] = {
> {.id = PORT_FEATURE_ID_ERROR,},
> {0,}
> @@ -227,4 +243,5 @@ const struct dfl_feature_id port_err_id_table[] = {
> const struct dfl_feature_ops port_err_ops = {
> .init = port_err_init,
> .uinit = port_err_uinit,
> + .ioctl = port_err_ioctl,
> };
> diff --git a/drivers/fpga/dfl-afu-main.c b/drivers/fpga/dfl-afu-main.c
> index 3fa2c59..b1ed7b4 100644
> --- a/drivers/fpga/dfl-afu-main.c
> +++ b/drivers/fpga/dfl-afu-main.c
> @@ -578,6 +578,7 @@ static int afu_release(struct inode *inode, struct file *filp)
> {
> struct platform_device *pdev = filp->private_data;
> struct dfl_feature_platform_data *pdata;
> + struct dfl_feature *feature;
>
> dev_dbg(&pdev->dev, "Device File Release\n");
>
> @@ -587,6 +588,9 @@ static int afu_release(struct inode *inode, struct file *filp)
> 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);
> __port_reset(pdev);
> afu_dma_region_destroy(pdata);
> }
> diff --git a/include/uapi/linux/fpga-dfl.h b/include/uapi/linux/fpga-dfl.h
> index 7331350..6c71c9d 100644
> --- a/include/uapi/linux/fpga-dfl.h
> +++ b/include/uapi/linux/fpga-dfl.h
> @@ -164,6 +164,29 @@ struct dfl_fpga_irq_set {
> __s32 evtfds[];
> };
>
> +/**
> + * DFL_FPGA_PORT_ERR_GET_IRQ_NUM - _IOR(DFL_FPGA_MAGIC, DFL_PORT_BASE + 5,
> + * __u32 num_irqs)
> + *
> + * Get the number of irqs supported by the fpga port error reporting private
> + * feature. Currently hardware supports up to 1 irq.
> + * Return: 0 on success, -errno on failure.
> + */
> +#define DFL_FPGA_PORT_ERR_GET_IRQ_NUM _IOR(DFL_FPGA_MAGIC, \
> + DFL_PORT_BASE + 5, __u32)
> +
> +/**
> + * DFL_FPGA_PORT_ERR_SET_IRQ - _IOW(DFL_FPGA_MAGIC, DFL_PORT_BASE + 6,
> + * struct dfl_fpga_irq_set)
> + *
> + * Set fpga port 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_PORT_ERR_SET_IRQ _IOW(DFL_FPGA_MAGIC, \
> + DFL_PORT_BASE + 6, \
> + struct dfl_fpga_irq_set)
> +
> /* IOCTLs for FME file descriptor */
>
> /**
> --
> 2.7.4

Reviewed-by: Marcelo Tosatti <mtosatti@redhat.com>