Re: [PATCH v5 09/28] fpga: dfl: add feature device infrastructure

Alan Tull
2018-06-05T21:14:43Z

On Tue, May 1, 2018 at 9:50 PM, Wu Hao <hao.wu@intel.com> wrote:

Hi Hao,

Some minor things, otherwise looks fine.

> From: Xiao Guangrong <guangrong.xiao@linux.intel.com>
>
> This patch abstracts the common operations of the sub features, and defines
> the feature_ops data structure, including init, uinit and ioctl function
> pointers. And this patch adds some common helper functions for FME and AFU
> drivers, e.g dfl_feature_dev_use_begin/end which are used to ensure
> exclusive usage of the feature device file.
>
> Signed-off-by: Tim Whisonant <tim.whisonant@intel.com>
> Signed-off-by: Enno Luebbers <enno.luebbers@intel.com>
> Signed-off-by: Shiva Rao <shiva.rao@intel.com>
> Signed-off-by: Christopher Rauer <christopher.rauer@intel.com>
> Signed-off-by: Kang Luwei <luwei.kang@intel.com>
> Signed-off-by: Zhang Yi <yi.z.zhang@intel.com>
> Signed-off-by: Xiao Guangrong <guangrong.xiao@linux.intel.com>
> Signed-off-by: Wu Hao <hao.wu@intel.com>
Acked-by: Alan Tull <atull@kernel.org>

> ---
> v2: rebased
> v3: use const for feature_ops.
> replace pci related function.
> v4: rebase and add more comments in code.
> v5: remove useless WARN_ON().
> reorder declarations in functions per suggestion from Moritz.
> add "dfl_" prefix to functions and data structure.
> ---
> drivers/fpga/dfl.c | 57 +++++++++++++++++++++++++++++++++++++
> drivers/fpga/dfl.h | 82 +++++++++++++++++++++++++++++++++++++++++++++++++++++-
> 2 files changed, 138 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/fpga/dfl.c b/drivers/fpga/dfl.c
> index 1e06efb..c4c47d6 100644
> --- a/drivers/fpga/dfl.c
> +++ b/drivers/fpga/dfl.c
> @@ -74,6 +74,63 @@ static enum dfl_id_type feature_dev_id_type(struct platform_device *pdev)
> return DFL_ID_MAX;
> }
>
> +void dfl_fpga_dev_feature_uinit(struct platform_device *pdev)
> +{
> + struct dfl_feature_platform_data *pdata = dev_get_platdata(&pdev->dev);
> + struct dfl_feature *feature;
> +
> + dfl_fpga_dev_for_each_feature(pdata, feature)
> + if (feature->ops) {
> + feature->ops->uinit(pdev, feature);
> + feature->ops = NULL;
> + }
> +}
> +EXPORT_SYMBOL_GPL(dfl_fpga_dev_feature_uinit);

Please add kernel-doc for functions that are exported to recommend and
guide their usage.

> +
> +static int dfl_feature_instance_init(struct platform_device *pdev,
> + struct dfl_feature_platform_data *pdata,
> + struct dfl_feature *feature,
> + struct dfl_feature_driver *drv)
> +{
> + int ret;
> +
> + ret = drv->ops->init(pdev, feature);
> + if (ret)
> + return ret;
> +
> + feature->ops = drv->ops;
> +
> + return ret;
> +}
> +
> +int dfl_fpga_dev_feature_init(struct platform_device *pdev,
> + struct dfl_feature_driver *feature_drvs)
> +{
> + struct dfl_feature_platform_data *pdata = dev_get_platdata(&pdev->dev);
> + struct dfl_feature_driver *drv = feature_drvs;
> + struct dfl_feature *feature;
> + int ret;
> +
> + while (drv->ops) {
> + dfl_fpga_dev_for_each_feature(pdata, feature) {
> + /* match feature and drv using id */
> + if (feature->id == drv->id) {
> + ret = dfl_feature_instance_init(pdev, pdata,
> + feature, drv);
> + if (ret)
> + goto exit;
> + }
> + }
> + drv++;
> + }
> +
> + return 0;
> +exit:
> + dfl_fpga_dev_feature_uinit(pdev);
> + return ret;
> +}
> +EXPORT_SYMBOL_GPL(dfl_fpga_dev_feature_init);
> +
> struct dfl_chardev_info {
> const char *name;
> dev_t devt;
> diff --git a/drivers/fpga/dfl.h b/drivers/fpga/dfl.h
> index 2b6aaef..27f7a74 100644
> --- a/drivers/fpga/dfl.h
> +++ b/drivers/fpga/dfl.h
> @@ -132,6 +132,17 @@
> #define PORT_CTRL_SFTRST_ACK BIT_ULL(4) /* HW ack for reset */
>
> /**
> + * struct dfl_feature_driver - sub feature's driver
> + *
> + * @id: sub feature id.
> + * @ops: ops of this sub feature.
> + */
> +struct dfl_feature_driver {
> + u64 id;
> + const struct dfl_feature_ops *ops;
> +};
> +
> +/**
> * struct dfl_feature - sub feature of the feature devices
> *
> * @id: sub feature id.
> @@ -139,13 +150,17 @@
> * this index is used to find its mmio resource from the
> * feature dev (platform device)'s reources.
> * @ioaddr: mapped mmio resource address.
> + * @ops: ops of this sub feature.
> */
> struct dfl_feature {
> u64 id;
> int resource_index;
> void __iomem *ioaddr;
> + const struct dfl_feature_ops *ops;
> };
>
> +#define DEV_STATUS_IN_USE 0
> +
> /**
> * struct dfl_feature_platform_data - platform data for feature devices
> *
> @@ -156,6 +171,8 @@ struct dfl_feature {
> * @dfl_cdev: ptr to container device.
> * @disable_count: count for port disable.
> * @num: number for sub features.
> + * @dev_status: dev status (e.g DEV_STATUS_IN_USE).
> + * @private: ptr to feature dev private data.
> * @features: sub features of this feature dev.
> */
> struct dfl_feature_platform_data {
> @@ -165,11 +182,49 @@ struct dfl_feature_platform_data {
> struct platform_device *dev;
> struct dfl_fpga_cdev *dfl_cdev;
> unsigned int disable_count;
> -
> + unsigned long dev_status;
> + void *private;
> int num;
> struct dfl_feature features[0];
> };
>
> +static inline
> +int dfl_feature_dev_use_begin(struct dfl_feature_platform_data *pdata)
> +{
> + /* Test and set IN_USE flags to ensure file is exclusively used */
> + if (test_and_set_bit_lock(DEV_STATUS_IN_USE, &pdata->dev_status))
> + return -EBUSY;
> +
> + return 0;
> +}
> +
> +static inline
> +void dfl_feature_dev_use_end(struct dfl_feature_platform_data *pdata)
> +{
> + clear_bit_unlock(DEV_STATUS_IN_USE, &pdata->dev_status);
> +}
> +
> +static inline
> +void dfl_fpga_pdata_set_private(struct dfl_feature_platform_data *pdata,
> + void *private)
> +{
> + pdata->private = private;
> +}
> +
> +static inline
> +void *dfl_fpga_pdata_get_private(struct dfl_feature_platform_data *pdata)
> +{
> + return pdata->private;
> +}
> +
> +struct dfl_feature_ops {
> + int (*init)(struct platform_device *pdev, struct dfl_feature *feature);
> + void (*uinit)(struct platform_device *pdev,
> + struct dfl_feature *feature);
> + long (*ioctl)(struct platform_device *pdev, struct dfl_feature *feature,
> + unsigned int cmd, unsigned long arg);
> +};
> +
> #define DFL_FPGA_FEATURE_DEV_FME "dfl-fme"
> #define DFL_FPGA_FEATURE_DEV_PORT "dfl-port"

Please move these to the same place as other things that will need to
be added to as feature devices are added as noted in the other reviews
today.

>
> @@ -179,6 +234,10 @@ static inline int dfl_feature_platform_data_size(const int num)
> num * sizeof(struct dfl_feature);
> }
>
> +void dfl_fpga_dev_feature_uinit(struct platform_device *pdev);
> +int dfl_fpga_dev_feature_init(struct platform_device *pdev,
> + struct dfl_feature_driver *feature_drvs);
> +
> enum dfl_fpga_devt_type {
> DFL_FPGA_DEVT_FME,
> DFL_FPGA_DEVT_PORT,
> @@ -190,6 +249,16 @@ int dfl_fpga_register_dev_ops(struct platform_device *pdev,
> struct module *owner);
> void dfl_fpga_unregister_dev_ops(struct platform_device *pdev);
>
> +static inline
> +struct platform_device *dfl_fpga_inode_to_feature_dev(struct inode *inode)
> +{
> + struct dfl_feature_platform_data *pdata;
> +
> + pdata = container_of(inode->i_cdev, struct dfl_feature_platform_data,
> + cdev);
> + return pdata->dev;
> +}
> +
> #define dfl_fpga_dev_for_each_feature(pdata, feature) \
> for ((feature) = (pdata)->features; \
> (feature) < (pdata)->features + (pdata)->num; (feature)++)
> @@ -219,6 +288,17 @@ void __iomem *dfl_get_feature_ioaddr_by_id(struct device *dev, u64 id)
> return NULL;
> }
>
> +static inline bool is_dfl_feature_present(struct device *dev, u64 id)
> +{
> + return !!dfl_get_feature_ioaddr_by_id(dev, id);
> +}
> +
> +static inline
> +struct device *dfl_fpga_pdata_to_parent(struct dfl_feature_platform_data *pdata)
> +{
> + return pdata->dev->dev.parent->parent;
> +}
> +
> static inline bool dfl_feature_is_fme(void __iomem *base)
> {
> u64 v = readq(base + DFH);
> --
> 1.8.3.1
>