[PATCH v2] drm/panthor: Enable timestamp propagation

From: Ashley Smith

Date: Thu Nov 27 2025 - 06:51:14 EST


Set the GLB_COUNTER_EN bit to enable coherent propagation of GPU
timestamp values to shader cores. This is a prerequisite for exposing
device-coherent timestamp queries.

Bump the version to 1.6 so userspace can detect support.

v2:
- GLB_COUNTER_EN is not a toggle bit move to panthor_fw_update_reqs

Signed-off-by: Ashley Smith <ashley.smith@xxxxxxxxxxxxx>
---
drivers/gpu/drm/panthor/panthor_drv.c | 3 ++-
drivers/gpu/drm/panthor/panthor_fw.c | 4 +++-
2 files changed, 5 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/panthor/panthor_drv.c b/drivers/gpu/drm/panthor/panthor_drv.c
index d1d4c50da5bf..0b0ec3b978c6 100644
--- a/drivers/gpu/drm/panthor/panthor_drv.c
+++ b/drivers/gpu/drm/panthor/panthor_drv.c
@@ -1604,6 +1604,7 @@ static void panthor_debugfs_init(struct drm_minor *minor)
* - 1.3 - adds DRM_PANTHOR_GROUP_STATE_INNOCENT flag
* - 1.4 - adds DRM_IOCTL_PANTHOR_BO_SET_LABEL ioctl
* - 1.5 - adds DRM_PANTHOR_SET_USER_MMIO_OFFSET ioctl
+ * - 1.6 - enables GLB_COUNTER_EN
*/
static const struct drm_driver panthor_drm_driver = {
.driver_features = DRIVER_RENDER | DRIVER_GEM | DRIVER_SYNCOBJ |
@@ -1617,7 +1618,7 @@ static const struct drm_driver panthor_drm_driver = {
.name = "panthor",
.desc = "Panthor DRM driver",
.major = 1,
- .minor = 5,
+ .minor = 6,

.gem_create_object = panthor_gem_create_object,
.gem_prime_import_sg_table = drm_gem_shmem_prime_import_sg_table,
diff --git a/drivers/gpu/drm/panthor/panthor_fw.c b/drivers/gpu/drm/panthor/panthor_fw.c
index 38d87ab92eda..a55731e95884 100644
--- a/drivers/gpu/drm/panthor/panthor_fw.c
+++ b/drivers/gpu/drm/panthor/panthor_fw.c
@@ -996,7 +996,9 @@ static void panthor_fw_init_global_iface(struct panthor_device *ptdev)
GLB_IDLE_EN |
GLB_IDLE;

- panthor_fw_update_reqs(glb_iface, req, GLB_IDLE_EN, GLB_IDLE_EN);
+ panthor_fw_update_reqs(glb_iface, req,
+ GLB_IDLE_EN | GLB_COUNTER_EN,
+ GLB_IDLE_EN | GLB_COUNTER_EN);
panthor_fw_toggle_reqs(glb_iface, req, ack,
GLB_CFG_ALLOC_EN |
GLB_CFG_POWEROFF_TIMER |

base-commit: 92c49b3f4df8f9acfa95551ef38fc00c675319fd
--
2.43.0