[PATCH v16 13/16] accel/rocket: add a GET_PARAM ioctl for the hardware version

[Jiaxing Hu <gahing@gahingwoo.com>]

Add DRM_IOCTL_ROCKET_GET_PARAM so that userspace can query the NPU
hardware version and pick the matching hardware description, such as the
SRAM configuration and the register layout.

Add DRM_ROCKET_PARAM_HW_VERSION, which returns a hardware version enum
that matches the device tree compatible.

The enum starts at 1 and 0 is not used:

  RK3588: 1
  RK3576: 2

An unknown parameter or a non-zero reserved field returns -EINVAL.

Signed-off-by: Jiaxing Hu <gahing@gahingwoo.com>
---
 drivers/accel/rocket/rocket_core.h |  1 +
 drivers/accel/rocket/rocket_drv.c  | 29 ++++++++++++++++++++++
 include/uapi/drm/rocket_accel.h    | 40 ++++++++++++++++++++++++++++++
 3 files changed, 70 insertions(+)

diff --git a/drivers/accel/rocket/rocket_core.h b/drivers/accel/rocket/rocket_core.h
index d5d353cc38e7..13d962467ff0 100644
--- a/drivers/accel/rocket/rocket_core.h
+++ b/drivers/accel/rocket/rocket_core.h
@@ -31,6 +31,7 @@ struct rocket_soc_data {
 	unsigned int num_clks;
 	unsigned int num_resets;
 	bool task_con_16bit;
+	u32 hw_version;
 };
 
 struct rocket_core {
diff --git a/drivers/accel/rocket/rocket_drv.c b/drivers/accel/rocket/rocket_drv.c
index fff31c1ebe52..c094f6843095 100644
--- a/drivers/accel/rocket/rocket_drv.c
+++ b/drivers/accel/rocket/rocket_drv.c
@@ -5,6 +5,7 @@
 #include <drm/drm_drv.h>
 #include <drm/drm_gem.h>
 #include <drm/drm_ioctl.h>
+#include <drm/drm_print.h>
 #include <drm/rocket_accel.h>
 #include <linux/clk.h>
 #include <linux/err.h>
@@ -129,6 +130,31 @@ rocket_postclose(struct drm_device *dev, struct drm_file *file)
 	module_put(THIS_MODULE);
 }
 
+static int
+rocket_ioctl_get_param(struct drm_device *dev, void *data, struct drm_file *file)
+{
+	struct rocket_device *rdev = to_rocket_device(dev);
+	struct drm_rocket_get_param *args = data;
+	const struct rocket_soc_data *soc;
+
+	if (args->reserved != 0) {
+		drm_dbg(dev, "Reserved field in drm_rocket_get_param struct should be 0.\n");
+		return -EINVAL;
+	}
+
+	soc = READ_ONCE(rdev->cores[0].soc);
+	if (!soc)
+		return -ENODEV;
+
+	switch (args->param) {
+	case DRM_ROCKET_PARAM_HW_VERSION:
+		args->value = soc->hw_version;
+		return 0;
+	default:
+		return -EINVAL;
+	}
+}
+
 static const struct drm_ioctl_desc rocket_drm_driver_ioctls[] = {
 #define ROCKET_IOCTL(n, func) \
 	DRM_IOCTL_DEF_DRV(ROCKET_##n, rocket_ioctl_##func, 0)
@@ -137,6 +163,7 @@ static const struct drm_ioctl_desc rocket_drm_driver_ioctls[] = {
 	ROCKET_IOCTL(SUBMIT, submit),
 	ROCKET_IOCTL(PREP_BO, prep_bo),
 	ROCKET_IOCTL(FINI_BO, fini_bo),
+	ROCKET_IOCTL(GET_PARAM, get_param),
 };
 
 DEFINE_DRM_ACCEL_FOPS(rocket_accel_driver_fops);
@@ -227,12 +254,14 @@ static const struct rocket_soc_data rk3588_soc_data = {
 	.num_clks = 4,
 	.num_resets = 2,
 	.task_con_16bit = false,
+	.hw_version = DRM_ROCKET_HW_RK3588,
 };
 
 static const struct rocket_soc_data rk3576_soc_data = {
 	.num_clks = 6,
 	.num_resets = 1,
 	.task_con_16bit = true,
+	.hw_version = DRM_ROCKET_HW_RK3576,
 };
 
 const struct of_device_id rocket_dt_match[] = {
diff --git a/include/uapi/drm/rocket_accel.h b/include/uapi/drm/rocket_accel.h
index d0685e372b79..597bf892c96d 100644
--- a/include/uapi/drm/rocket_accel.h
+++ b/include/uapi/drm/rocket_accel.h
@@ -15,11 +15,13 @@ extern "C" {
 #define DRM_ROCKET_SUBMIT			0x01
 #define DRM_ROCKET_PREP_BO			0x02
 #define DRM_ROCKET_FINI_BO			0x03
+#define DRM_ROCKET_GET_PARAM			0x04
 
 #define DRM_IOCTL_ROCKET_CREATE_BO		DRM_IOWR(DRM_COMMAND_BASE + DRM_ROCKET_CREATE_BO, struct drm_rocket_create_bo)
 #define DRM_IOCTL_ROCKET_SUBMIT			DRM_IOW(DRM_COMMAND_BASE + DRM_ROCKET_SUBMIT, struct drm_rocket_submit)
 #define DRM_IOCTL_ROCKET_PREP_BO		DRM_IOW(DRM_COMMAND_BASE + DRM_ROCKET_PREP_BO, struct drm_rocket_prep_bo)
 #define DRM_IOCTL_ROCKET_FINI_BO		DRM_IOW(DRM_COMMAND_BASE + DRM_ROCKET_FINI_BO, struct drm_rocket_fini_bo)
+#define DRM_IOCTL_ROCKET_GET_PARAM		DRM_IOWR(DRM_COMMAND_BASE + DRM_ROCKET_GET_PARAM, struct drm_rocket_get_param)
 
 /**
  * struct drm_rocket_create_bo - ioctl argument for creating Rocket BOs.
@@ -185,6 +187,44 @@ struct drm_rocket_submit {
 	__u64 reserved;
 };
 
+/**
+ * enum drm_rocket_param - parameters for DRM_IOCTL_ROCKET_GET_PARAM
+ * @DRM_ROCKET_PARAM_HW_VERSION: an enum drm_rocket_hw_version value.
+ */
+enum drm_rocket_param {
+	DRM_ROCKET_PARAM_HW_VERSION = 0,
+};
+
+/**
+ * enum drm_rocket_hw_version - the NPU, one value per DT compatible
+ * @DRM_ROCKET_HW_RK3588: "rockchip,rk3588-rknn-core"
+ * @DRM_ROCKET_HW_RK3576: "rockchip,rk3576-rknn-core"
+ */
+enum drm_rocket_hw_version {
+	DRM_ROCKET_HW_RK3588 = 1,
+	DRM_ROCKET_HW_RK3576 = 2,
+};
+
+/**
+ * struct drm_rocket_get_param - ioctl argument for querying a parameter.
+ */
+struct drm_rocket_get_param {
+	/**
+	 * @param: Input: an enum drm_rocket_param value.
+	 */
+	__u32 param;
+
+	/**
+	 * @reserved: Reserved, must be zero.
+	 */
+	__u32 reserved;
+
+	/**
+	 * @value: Output: the value of the parameter.
+	 */
+	__u64 value;
+};
+
 #if defined(__cplusplus)
 }
 #endif
-- 
2.43.0