[PATCH v4 07/24] fpga: dfl: add feature device infrastructure

From: Wu Hao
Date: Tue Feb 13 2018 - 04:35:47 EST


From: Xiao Guangrong <guangrong.xiao@xxxxxxxxxxxxxxx>

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 feature_dev_use_begin/end which are used to ensure exclusive
usage of the feature device file.

Signed-off-by: Tim Whisonant <tim.whisonant@xxxxxxxxx>
Signed-off-by: Enno Luebbers <enno.luebbers@xxxxxxxxx>
Signed-off-by: Shiva Rao <shiva.rao@xxxxxxxxx>
Signed-off-by: Christopher Rauer <christopher.rauer@xxxxxxxxx>
Signed-off-by: Kang Luwei <luwei.kang@xxxxxxxxx>
Signed-off-by: Zhang Yi <yi.z.zhang@xxxxxxxxx>
Signed-off-by: Xiao Guangrong <guangrong.xiao@xxxxxxxxxxxxxxx>
Signed-off-by: Wu Hao <hao.wu@xxxxxxxxx>
---
v2: rebased
v3: use const for feature_ops.
replace pci related function.
v4: rebase and add more comments in code.
---
drivers/fpga/dfl.c | 59 +++++++++++++++++++++++++++++++++++++
drivers/fpga/dfl.h | 85 +++++++++++++++++++++++++++++++++++++++++++++++++++++-
2 files changed, 143 insertions(+), 1 deletion(-)

diff --git a/drivers/fpga/dfl.c b/drivers/fpga/dfl.c
index 38dc819..c0aad87 100644
--- a/drivers/fpga/dfl.c
+++ b/drivers/fpga/dfl.c
@@ -74,6 +74,65 @@ static enum fpga_id_type feature_dev_id_type(struct platform_device *pdev)
return FPGA_ID_MAX;
}

+void fpga_dev_feature_uinit(struct platform_device *pdev)
+{
+ struct feature *feature;
+ struct feature_platform_data *pdata = dev_get_platdata(&pdev->dev);
+
+ fpga_dev_for_each_feature(pdata, feature)
+ if (feature->ops) {
+ feature->ops->uinit(pdev, feature);
+ feature->ops = NULL;
+ }
+}
+EXPORT_SYMBOL_GPL(fpga_dev_feature_uinit);
+
+static int
+feature_instance_init(struct platform_device *pdev,
+ struct feature_platform_data *pdata,
+ struct feature *feature, struct feature_driver *drv)
+{
+ int ret;
+
+ WARN_ON(!feature->ioaddr);
+
+ ret = drv->ops->init(pdev, feature);
+ if (ret)
+ return ret;
+
+ feature->ops = drv->ops;
+
+ return ret;
+}
+
+int fpga_dev_feature_init(struct platform_device *pdev,
+ struct feature_driver *feature_drvs)
+{
+ struct feature *feature;
+ struct feature_driver *drv = feature_drvs;
+ struct feature_platform_data *pdata = dev_get_platdata(&pdev->dev);
+ int ret;
+
+ while (drv->ops) {
+ fpga_dev_for_each_feature(pdata, feature) {
+ /* match feature and drv using id */
+ if (feature->id == drv->id) {
+ ret = feature_instance_init(pdev, pdata,
+ feature, drv);
+ if (ret)
+ goto exit;
+ }
+ }
+ drv++;
+ }
+
+ return 0;
+exit:
+ fpga_dev_feature_uinit(pdev);
+ return ret;
+}
+EXPORT_SYMBOL_GPL(fpga_dev_feature_init);
+
struct fpga_chardev_info {
const char *name;
dev_t devt;
diff --git a/drivers/fpga/dfl.h b/drivers/fpga/dfl.h
index d6ecda1..ede1e95 100644
--- a/drivers/fpga/dfl.h
+++ b/drivers/fpga/dfl.h
@@ -132,6 +132,17 @@
#define PORT_CTRL_SFTRST_ACK BIT(4) /* HW ack for reset */

/**
+ * struct feature_driver - sub feature's driver
+ *
+ * @id: sub feature id.
+ * @ops: ops of this sub feature.
+ */
+struct feature_driver {
+ u64 id;
+ const struct feature_ops *ops;
+};
+
+/**
* struct 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 feature {
u64 id;
int resource_index;
void __iomem *ioaddr;
+ const struct feature_ops *ops;
};

+#define DEV_STATUS_IN_USE 0
+
/**
* struct feature_platform_data - platform data for feature devices
*
@@ -155,6 +170,8 @@ struct feature {
* @dev: ptr to platform device linked with this platform data.
* @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 feature_platform_data {
@@ -163,11 +180,44 @@ struct feature_platform_data {
struct cdev cdev;
struct platform_device *dev;
unsigned int disable_count;
-
+ unsigned long dev_status;
+ void *private;
int num;
struct feature features[0];
};

+static inline int feature_dev_use_begin(struct 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 feature_dev_use_end(struct feature_platform_data *pdata)
+{
+ clear_bit_unlock(DEV_STATUS_IN_USE, &pdata->dev_status);
+}
+
+static inline void
+fpga_pdata_set_private(struct feature_platform_data *pdata, void *private)
+{
+ pdata->private = private;
+}
+
+static inline void *fpga_pdata_get_private(struct feature_platform_data *pdata)
+{
+ return pdata->private;
+}
+
+struct feature_ops {
+ int (*init)(struct platform_device *pdev, struct feature *feature);
+ void (*uinit)(struct platform_device *pdev, struct feature *feature);
+ long (*ioctl)(struct platform_device *pdev, struct feature *feature,
+ unsigned int cmd, unsigned long arg);
+};
+
#define FPGA_FEATURE_DEV_FME "dfl-fme"
#define FPGA_FEATURE_DEV_PORT "dfl-port"

@@ -177,6 +227,10 @@ static inline int feature_platform_data_size(const int num)
num * sizeof(struct feature);
}

+void fpga_dev_feature_uinit(struct platform_device *pdev);
+int fpga_dev_feature_init(struct platform_device *pdev,
+ struct feature_driver *feature_drvs);
+
enum fpga_devt_type {
FPGA_DEVT_FME,
FPGA_DEVT_PORT,
@@ -257,6 +311,15 @@ static inline int fpga_port_reset(struct platform_device *pdev)
return ret;
}

+static inline
+struct platform_device *fpga_inode_to_feature_dev(struct inode *inode)
+{
+ struct feature_platform_data *pdata;
+
+ pdata = container_of(inode->i_cdev, struct feature_platform_data, cdev);
+ return pdata->dev;
+}
+
#define fpga_dev_for_each_feature(pdata, feature) \
for ((feature) = (pdata)->features; \
(feature) < (pdata)->features + (pdata)->num; (feature)++)
@@ -284,6 +347,17 @@ static inline void __iomem *get_feature_ioaddr_by_id(struct device *dev, u64 id)
return NULL;
}

+static inline bool is_feature_present(struct device *dev, u64 id)
+{
+ return !!get_feature_ioaddr_by_id(dev, id);
+}
+
+static inline struct device *
+fpga_pdata_to_parent(struct feature_platform_data *pdata)
+{
+ return pdata->dev->dev.parent->parent;
+}
+
static inline bool feature_is_fme(void __iomem *base)
{
u64 v = readq(base + DFH);
@@ -376,4 +450,13 @@ fpga_cdev_find_port(struct fpga_cdev *cdev, void *data,

return pdev;
}
+
+static inline struct fpga_cdev *
+fpga_pdata_to_fpga_cdev(struct feature_platform_data *pdata)
+{
+ struct device *dev = pdata->dev->dev.parent;
+ struct fpga_region *region = to_fpga_region(dev);
+
+ return container_of(region, struct fpga_cdev, region);
+}
#endif /* __FPGA_DFL_H */
--
2.7.4