[PATCH 1/7 v2] drm/vc4: Add a getparam ioctl for getting the V3D identity regs.

From: Eric Anholt
Date: Tue Jul 12 2016 - 14:06:41 EST


As I extend the driver to support different V3D revisions, userspace
needs to know what version it's targeting. This is most easily
detected using the V3D identity registers.

v2: Make sure V3D is runtime PM on when reading the registers.

Signed-off-by: Eric Anholt <eric@xxxxxxxxxx>
---
drivers/gpu/drm/vc4/vc4_drv.c | 39 +++++++++++++++++++++++++++++++++++++++
include/uapi/drm/vc4_drm.h | 11 +++++++++++
2 files changed, 50 insertions(+)

diff --git a/drivers/gpu/drm/vc4/vc4_drv.c b/drivers/gpu/drm/vc4/vc4_drv.c
index 2f30214ee810..56d43f5f38fb 100644
--- a/drivers/gpu/drm/vc4/vc4_drv.c
+++ b/drivers/gpu/drm/vc4/vc4_drv.c
@@ -14,6 +14,7 @@
#include <linux/module.h>
#include <linux/of_platform.h>
#include <linux/platform_device.h>
+#include <linux/pm_runtime.h>
#include "drm_fb_cma_helper.h"

#include "uapi/drm/vc4_drm.h"
@@ -43,6 +44,43 @@ void __iomem *vc4_ioremap_regs(struct platform_device *dev, int index)
return map;
}

+static int vc4_get_param_ioctl(struct drm_device *dev, void *data,
+ struct drm_file *file_priv)
+{
+ struct vc4_dev *vc4 = to_vc4_dev(dev);
+ struct drm_vc4_get_param *args = data;
+ int ret;
+
+ switch (args->param) {
+ case DRM_VC4_PARAM_V3D_IDENT0:
+ ret = pm_runtime_get_sync(&vc4->v3d->pdev->dev);
+ if (ret)
+ return ret;
+ args->value = V3D_READ(V3D_IDENT0);
+ pm_runtime_put(&vc4->v3d->pdev->dev);
+ break;
+ case DRM_VC4_PARAM_V3D_IDENT1:
+ ret = pm_runtime_get_sync(&vc4->v3d->pdev->dev);
+ if (ret)
+ return ret;
+ args->value = V3D_READ(V3D_IDENT1);
+ pm_runtime_put(&vc4->v3d->pdev->dev);
+ break;
+ case DRM_VC4_PARAM_V3D_IDENT2:
+ ret = pm_runtime_get_sync(&vc4->v3d->pdev->dev);
+ if (ret)
+ return ret;
+ args->value = V3D_READ(V3D_IDENT2);
+ pm_runtime_put(&vc4->v3d->pdev->dev);
+ break;
+ default:
+ DRM_DEBUG("Unknown parameter %d\n", args->param);
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
static void vc4_lastclose(struct drm_device *dev)
{
struct vc4_dev *vc4 = to_vc4_dev(dev);
@@ -74,6 +112,7 @@ static const struct drm_ioctl_desc vc4_drm_ioctls[] = {
DRM_IOCTL_DEF_DRV(VC4_CREATE_SHADER_BO, vc4_create_shader_bo_ioctl, DRM_RENDER_ALLOW),
DRM_IOCTL_DEF_DRV(VC4_GET_HANG_STATE, vc4_get_hang_state_ioctl,
DRM_ROOT_ONLY),
+ DRM_IOCTL_DEF_DRV(VC4_GET_PARAM, vc4_get_param_ioctl, DRM_RENDER_ALLOW),
};

static struct drm_driver vc4_drm_driver = {
diff --git a/include/uapi/drm/vc4_drm.h b/include/uapi/drm/vc4_drm.h
index af12e8a184c8..c4427d31b346 100644
--- a/include/uapi/drm/vc4_drm.h
+++ b/include/uapi/drm/vc4_drm.h
@@ -37,6 +37,7 @@ extern "C" {
#define DRM_VC4_MMAP_BO 0x04
#define DRM_VC4_CREATE_SHADER_BO 0x05
#define DRM_VC4_GET_HANG_STATE 0x06
+#define DRM_VC4_GET_PARAM 0x07

#define DRM_IOCTL_VC4_SUBMIT_CL DRM_IOWR(DRM_COMMAND_BASE + DRM_VC4_SUBMIT_CL, struct drm_vc4_submit_cl)
#define DRM_IOCTL_VC4_WAIT_SEQNO DRM_IOWR(DRM_COMMAND_BASE + DRM_VC4_WAIT_SEQNO, struct drm_vc4_wait_seqno)
@@ -45,6 +46,7 @@ extern "C" {
#define DRM_IOCTL_VC4_MMAP_BO DRM_IOWR(DRM_COMMAND_BASE + DRM_VC4_MMAP_BO, struct drm_vc4_mmap_bo)
#define DRM_IOCTL_VC4_CREATE_SHADER_BO DRM_IOWR(DRM_COMMAND_BASE + DRM_VC4_CREATE_SHADER_BO, struct drm_vc4_create_shader_bo)
#define DRM_IOCTL_VC4_GET_HANG_STATE DRM_IOWR(DRM_COMMAND_BASE + DRM_VC4_GET_HANG_STATE, struct drm_vc4_get_hang_state)
+#define DRM_IOCTL_VC4_GET_PARAM DRM_IOWR(DRM_COMMAND_BASE + DRM_VC4_GET_PARAM, struct drm_vc4_get_param)

struct drm_vc4_submit_rcl_surface {
__u32 hindex; /* Handle index, or ~0 if not present. */
@@ -280,6 +282,15 @@ struct drm_vc4_get_hang_state {
__u32 pad[16];
};

+#define DRM_VC4_PARAM_V3D_IDENT0 0
+#define DRM_VC4_PARAM_V3D_IDENT1 1
+#define DRM_VC4_PARAM_V3D_IDENT2 2
+
+struct drm_vc4_get_param {
+ __u32 param;
+ __u32 value;
+};
+
#if defined(__cplusplus)
}
#endif
--
2.8.1