If we do a GPU soft-reset, that's no longer fast reset. This also means
the slow reset fallback doesn't work because the MCU state is only reset
after a GPU soft-reset.
Let's move the retry logic to panthor_device_resume() to issue a
soft-reset between the fast and slow attempts, and patch
panthor_gpu_suspend() to only power-off the L2 when a fast reset is
requested.
v2:
- Add R-b
Signed-off-by: Boris Brezillon <boris.brezil...@collabora.com>
Reviewed-by: Steven Price <steven.pr...@arm.com>
---
drivers/gpu/drm/panthor/panthor_device.c | 32 ++++++++++----
drivers/gpu/drm/panthor/panthor_device.h | 11 +++++
drivers/gpu/drm/panthor/panthor_fw.c | 54 ++++++------------------
drivers/gpu/drm/panthor/panthor_gpu.c | 11 ++---
4 files changed, 53 insertions(+), 55 deletions(-)
diff --git a/drivers/gpu/drm/panthor/panthor_device.c
b/drivers/gpu/drm/panthor/panthor_device.c
index 0362101ea896..2c817e65e6be 100644
--- a/drivers/gpu/drm/panthor/panthor_device.c
+++ b/drivers/gpu/drm/panthor/panthor_device.c
@@ -431,6 +431,22 @@ int panthor_device_mmap_io(struct panthor_device *ptdev,
struct vm_area_struct *
return 0;
}
+static int panthor_device_resume_hw_components(struct panthor_device *ptdev)
+{
+ int ret;
+
+ panthor_gpu_resume(ptdev);
+ panthor_mmu_resume(ptdev);
+
+ ret = panthor_fw_resume(ptdev);
+ if (!ret)
+ return 0;
+
+ panthor_mmu_suspend(ptdev);
+ panthor_gpu_suspend(ptdev);
+ return ret;
+}
+
int panthor_device_resume(struct device *dev)
{
struct panthor_device *ptdev = dev_get_drvdata(dev);
@@ -457,16 +473,16 @@ int panthor_device_resume(struct device *dev)
if (panthor_device_is_initialized(ptdev) &&
drm_dev_enter(&ptdev->base, &cookie)) {
- panthor_gpu_resume(ptdev);
- panthor_mmu_resume(ptdev);
- ret = panthor_fw_resume(ptdev);
- if (!drm_WARN_ON(&ptdev->base, ret)) {
- panthor_sched_resume(ptdev);
- } else {
- panthor_mmu_suspend(ptdev);
- panthor_gpu_suspend(ptdev);
+ ret = panthor_device_resume_hw_components(ptdev);
+ if (ret && ptdev->reset.fast) {
+ drm_err(&ptdev->base, "Fast reset failed, trying a slow
reset");
+ ptdev->reset.fast = false;
+ ret = panthor_device_resume_hw_components(ptdev);
}
+ if (!ret)
+ panthor_sched_resume(ptdev);
+
drm_dev_exit(cookie);
if (ret)
diff --git a/drivers/gpu/drm/panthor/panthor_device.h
b/drivers/gpu/drm/panthor/panthor_device.h
index b6c4f25a5d6e..da6574021664 100644
--- a/drivers/gpu/drm/panthor/panthor_device.h
+++ b/drivers/gpu/drm/panthor/panthor_device.h
@@ -157,6 +157,17 @@ struct panthor_device {
/** @pending: Set to true if a reset is pending. */
atomic_t pending;
+
+ /**
+ * @fast: True if the post_reset logic can proceed with a fast
reset.
+ *
+ * A fast reset is just a reset where the driver doesn't reload
the FW sections.
+ *
+ * Any time the firmware is properly suspended, a fast reset
can take place.
+ * On the other hand, if the halt operation failed, the driver
will reload
+ * all FW sections to make sure we start from a fresh state.
+ */
+ bool fast;
} reset;
/** @pm: Power management related data. */
diff --git a/drivers/gpu/drm/panthor/panthor_fw.c
b/drivers/gpu/drm/panthor/panthor_fw.c
index f3d3d8fbe13d..a3d11d32b71c 100644
--- a/drivers/gpu/drm/panthor/panthor_fw.c
+++ b/drivers/gpu/drm/panthor/panthor_fw.c
@@ -263,17 +263,6 @@ struct panthor_fw {
/** @booted: True is the FW is booted */
bool booted;
- /**
- * @fast_reset: True if the post_reset logic can proceed with a fast
reset.
- *
- * A fast reset is just a reset where the driver doesn't reload the FW
sections.
- *
- * Any time the firmware is properly suspended, a fast reset can take
place.
- * On the other hand, if the halt operation failed, the driver will
reload
- * all sections to make sure we start from a fresh state.
- */
- bool fast_reset;
-
/** @irq: Job irq data. */
struct panthor_irq irq;
};
@@ -1090,7 +1079,7 @@ void panthor_fw_pre_reset(struct panthor_device *ptdev,
bool on_hang)
/* Make sure we won't be woken up by a ping. */
cancel_delayed_work_sync(&ptdev->fw->watchdog.ping_work);
- ptdev->fw->fast_reset = false;
+ ptdev->reset.fast = false;
if (!on_hang) {
struct panthor_fw_global_iface *glb_iface =
panthor_fw_get_glb_iface(ptdev);
@@ -1100,7 +1089,7 @@ void panthor_fw_pre_reset(struct panthor_device *ptdev,
bool on_hang)
gpu_write(ptdev, CSF_DOORBELL(CSF_GLB_DOORBELL_ID), 1);
if (!readl_poll_timeout(ptdev->iomem + MCU_STATUS, status,
status == MCU_STATUS_HALT, 10, 100000))
{
- ptdev->fw->fast_reset = true;
+ ptdev->reset.fast = true;
} else {
drm_warn(&ptdev->base, "Failed to cleanly suspend MCU");
}
@@ -1125,49 +1114,30 @@ int panthor_fw_post_reset(struct panthor_device *ptdev)
if (ret)
return ret;
- /* If this is a fast reset, try to start the MCU without reloading
- * the FW sections. If it fails, go for a full reset.
- */
- if (ptdev->fw->fast_reset) {
+ if (!ptdev->reset.fast) {
+ /* On a slow reset, reload all sections, including RO ones.
+ * We're not supposed to end up here anyway, let's just assume
+ * the overhead of reloading everything is acceptable.
+ */
+ panthor_reload_fw_sections(ptdev, true);
+ } else {
/* The FW detects 0 -> 1 transitions. Make sure we reset
* the HALT bit before the FW is rebooted.
* This is not needed on a slow reset because FW sections are
* re-initialized.
*/
struct panthor_fw_global_iface *glb_iface =
panthor_fw_get_glb_iface(ptdev);
+
panthor_fw_update_reqs(glb_iface, req, 0, GLB_HALT);
-
- ret = panthor_fw_start(ptdev);
- if (!ret)
- goto out;
-
- /* Forcibly reset the MCU and force a slow reset, so we get a
- * fresh boot on the next panthor_fw_start() call.
- */
- panthor_fw_stop(ptdev);
- ptdev->fw->fast_reset = false;
- drm_err(&ptdev->base, "FW fast reset failed, trying a slow
reset");
-
- ret = panthor_vm_flush_all(ptdev->fw->vm);
- if (ret) {
- drm_err(&ptdev->base, "FW slow reset failed (couldn't
flush FW's AS l2cache)");
- return ret;
- }
}
- /* Reload all sections, including RO ones. We're not supposed
- * to end up here anyway, let's just assume the overhead of
- * reloading everything is acceptable.
- */
- panthor_reload_fw_sections(ptdev, true);
-
ret = panthor_fw_start(ptdev);
if (ret) {
- drm_err(&ptdev->base, "FW slow reset failed (couldn't start the
FW )");
+ drm_err(&ptdev->base, "FW %s reset failed",
+ ptdev->reset.fast ? "fast" : "slow");
return ret;
}
-out:
/* We must re-initialize the global interface even on fast-reset. */
panthor_fw_init_global_iface(ptdev);
return 0;
diff --git a/drivers/gpu/drm/panthor/panthor_gpu.c
b/drivers/gpu/drm/panthor/panthor_gpu.c
index ee85a371bc38..671049020afa 100644
--- a/drivers/gpu/drm/panthor/panthor_gpu.c
+++ b/drivers/gpu/drm/panthor/panthor_gpu.c
@@ -470,11 +470,12 @@ int panthor_gpu_soft_reset(struct panthor_device *ptdev)
*/
void panthor_gpu_suspend(struct panthor_device *ptdev)
{
- /*
- * It may be preferable to simply power down the L2, but for now just
- * soft-reset which will leave the L2 powered down.
- */
- panthor_gpu_soft_reset(ptdev);
+ /* On a fast reset, simply power down the L2. */
+ if (!ptdev->reset.fast)
+ panthor_gpu_soft_reset(ptdev);
+ else
+ panthor_gpu_power_off(ptdev, L2, 1, 20000);
+
panthor_gpu_irq_suspend(&ptdev->gpu->irq);
}
--
2.46.2
