drm/amdkfd: Add support for user-mode trap handlers

A second-level user mode trap handler can be installed. The CWSR trap
handler jumps to the secondary trap handler conditionally for any
conditions not handled by it. This can be used e.g. for debugging or
catching math exceptions.

When CWSR is disabled, the user mode trap handler is installed as
first level trap handler.

Signed-off-by: Shaoyun.liu <shaoyun.liu@amd.com>
Signed-off-by: Jay Cornwall <Jay.Cornwall@amd.com>
Signed-off-by: Felix Kuehling <Felix.Kuehling@amd.com>
Signed-off-by: Oded Gabbay <oded.gabbay@gmail.com>

1 files changed, 36 insertions, 1 deletions

diff --git a/drivers/gpu/drm/amd/amdkfd/kfd_chardev.c b/drivers/gpu/drm/amd/amdkfd/kfd_chardev.c
index 2a4612d8437a..cc61ec289880 100644
--- a/drivers/gpu/drm/amd/amdkfd/kfd_chardev.c
+++ b/drivers/gpu/drm/amd/amdkfd/kfd_chardev.c
@@ -432,6 +432,38 @@ out:
 	return err;
 }
 
+static int kfd_ioctl_set_trap_handler(struct file *filep,
+					struct kfd_process *p, void *data)
+{
+	struct kfd_ioctl_set_trap_handler_args *args = data;
+	struct kfd_dev *dev;
+	int err = 0;
+	struct kfd_process_device *pdd;
+
+	dev = kfd_device_by_id(args->gpu_id);
+	if (dev == NULL)
+		return -EINVAL;
+
+	mutex_lock(&p->mutex);
+
+	pdd = kfd_bind_process_to_device(dev, p);
+	if (IS_ERR(pdd)) {
+		err = -ESRCH;
+		goto out;
+	}
+
+	if (dev->dqm->ops.set_trap_handler(dev->dqm,
+					&pdd->qpd,
+					args->tba_addr,
+					args->tma_addr))
+		err = -EINVAL;
+
+out:
+	mutex_unlock(&p->mutex);
+
+	return err;
+}
+
 static int kfd_ioctl_dbg_register(struct file *filep,
 				struct kfd_process *p, void *data)
 {
@@ -980,7 +1012,10 @@ static const struct amdkfd_ioctl_desc amdkfd_ioctls[] = {
 			kfd_ioctl_set_scratch_backing_va, 0),
 
 	AMDKFD_IOCTL_DEF(AMDKFD_IOC_GET_TILE_CONFIG,
-			kfd_ioctl_get_tile_config, 0)
+			kfd_ioctl_get_tile_config, 0),
+
+	AMDKFD_IOCTL_DEF(AMDKFD_IOC_SET_TRAP_HANDLER,
+			kfd_ioctl_set_trap_handler, 0),
 };
 
 #define AMDKFD_CORE_IOCTL_COUNT	ARRAY_SIZE(amdkfd_ioctls)