[PATCH] accel/ivpu: Don't enter d0i3 during FLR

[Stanislaw Gruszka]

From: Jacek Lawrynowicz <jacek.lawrynowicz at linux.intel.com>

Fix a bug on some platforms where FLR causes complete system
hang when CPU is low power states (C8 or above).

Fixes: 852be13f3bd3 ("accel/ivpu: Add PM support")
Cc: stable at vger.kernel.org
Signed-off-by: Jacek Lawrynowicz <jacek.lawrynowicz at linux.intel.com>
Reviewed-by: Stanislaw Gruszka <stanislaw.gruszka at linux.intel.com>
Signed-off-by: Stanislaw Gruszka <stanislaw.gruszka at linux.intel.com>
---
 drivers/accel/ivpu/ivpu_drv.c     | 11 ++++++++---
 drivers/accel/ivpu/ivpu_drv.h     |  1 +
 drivers/accel/ivpu/ivpu_hw.h      |  8 ++++++++
 drivers/accel/ivpu/ivpu_hw_37xx.c |  1 +
 drivers/accel/ivpu/ivpu_hw_40xx.c |  1 +
 drivers/accel/ivpu/ivpu_pm.c      |  3 ++-
 6 files changed, 21 insertions(+), 4 deletions(-)

diff --git a/drivers/accel/ivpu/ivpu_drv.c b/drivers/accel/ivpu/ivpu_drv.c
index 3f4efa07ce7c..1eb232e903e8 100644
--- a/drivers/accel/ivpu/ivpu_drv.c
+++ b/drivers/accel/ivpu/ivpu_drv.c
@@ -367,14 +367,19 @@ int ivpu_boot(struct ivpu_device *vdev)
 	return 0;
 }
 
-int ivpu_shutdown(struct ivpu_device *vdev)
+void ivpu_prepare_for_reset(struct ivpu_device *vdev)
 {
-	int ret;
-
 	ivpu_hw_irq_disable(vdev);
 	disable_irq(vdev->irq);
 	ivpu_ipc_disable(vdev);
 	ivpu_mmu_disable(vdev);
+}
+
+int ivpu_shutdown(struct ivpu_device *vdev)
+{
+	int ret;
+
+	ivpu_prepare_for_reset(vdev);
 
 	ret = ivpu_hw_power_down(vdev);
 	if (ret)
diff --git a/drivers/accel/ivpu/ivpu_drv.h b/drivers/accel/ivpu/ivpu_drv.h
index 98380c1db9fa..a3b45032e6cf 100644
--- a/drivers/accel/ivpu/ivpu_drv.h
+++ b/drivers/accel/ivpu/ivpu_drv.h
@@ -158,6 +158,7 @@ void ivpu_file_priv_put(struct ivpu_file_priv **link);
 
 int ivpu_boot(struct ivpu_device *vdev);
 int ivpu_shutdown(struct ivpu_device *vdev);
+void ivpu_prepare_for_reset(struct ivpu_device *vdev);
 
 static inline u8 ivpu_revision(struct ivpu_device *vdev)
 {
diff --git a/drivers/accel/ivpu/ivpu_hw.h b/drivers/accel/ivpu/ivpu_hw.h
index ab341237bcf9..1079e06255ba 100644
--- a/drivers/accel/ivpu/ivpu_hw.h
+++ b/drivers/accel/ivpu/ivpu_hw.h
@@ -13,6 +13,7 @@ struct ivpu_hw_ops {
 	int (*power_up)(struct ivpu_device *vdev);
 	int (*boot_fw)(struct ivpu_device *vdev);
 	int (*power_down)(struct ivpu_device *vdev);
+	int (*reset)(struct ivpu_device *vdev);
 	bool (*is_idle)(struct ivpu_device *vdev);
 	void (*wdt_disable)(struct ivpu_device *vdev);
 	void (*diagnose_failure)(struct ivpu_device *vdev);
@@ -91,6 +92,13 @@ static inline int ivpu_hw_power_down(struct ivpu_device *vdev)
 	return vdev->hw->ops->power_down(vdev);
 };
 
+static inline int ivpu_hw_reset(struct ivpu_device *vdev)
+{
+	ivpu_dbg(vdev, PM, "HW reset\n");
+
+	return vdev->hw->ops->reset(vdev);
+};
+
 static inline void ivpu_hw_wdt_disable(struct ivpu_device *vdev)
 {
 	vdev->hw->ops->wdt_disable(vdev);
diff --git a/drivers/accel/ivpu/ivpu_hw_37xx.c b/drivers/accel/ivpu/ivpu_hw_37xx.c
index edd4d860f135..1e842739e937 100644
--- a/drivers/accel/ivpu/ivpu_hw_37xx.c
+++ b/drivers/accel/ivpu/ivpu_hw_37xx.c
@@ -1036,6 +1036,7 @@ const struct ivpu_hw_ops ivpu_hw_37xx_ops = {
 	.power_up = ivpu_hw_37xx_power_up,
 	.is_idle = ivpu_hw_37xx_is_idle,
 	.power_down = ivpu_hw_37xx_power_down,
+	.reset = ivpu_hw_37xx_reset,
 	.boot_fw = ivpu_hw_37xx_boot_fw,
 	.wdt_disable = ivpu_hw_37xx_wdt_disable,
 	.diagnose_failure = ivpu_hw_37xx_diagnose_failure,
diff --git a/drivers/accel/ivpu/ivpu_hw_40xx.c b/drivers/accel/ivpu/ivpu_hw_40xx.c
index a48cd36f9931..d7b8ec0410af 100644
--- a/drivers/accel/ivpu/ivpu_hw_40xx.c
+++ b/drivers/accel/ivpu/ivpu_hw_40xx.c
@@ -1186,6 +1186,7 @@ const struct ivpu_hw_ops ivpu_hw_40xx_ops = {
 	.power_up = ivpu_hw_40xx_power_up,
 	.is_idle = ivpu_hw_40xx_is_idle,
 	.power_down = ivpu_hw_40xx_power_down,
+	.reset = ivpu_hw_40xx_reset,
 	.boot_fw = ivpu_hw_40xx_boot_fw,
 	.wdt_disable = ivpu_hw_40xx_wdt_disable,
 	.diagnose_failure = ivpu_hw_40xx_diagnose_failure,
diff --git a/drivers/accel/ivpu/ivpu_pm.c b/drivers/accel/ivpu/ivpu_pm.c
index 28a0d1111e12..da46f95b008a 100644
--- a/drivers/accel/ivpu/ivpu_pm.c
+++ b/drivers/accel/ivpu/ivpu_pm.c
@@ -261,7 +261,8 @@ void ivpu_pm_reset_prepare_cb(struct pci_dev *pdev)
 	ivpu_dbg(vdev, PM, "Pre-reset..\n");
 	atomic_inc(&vdev->pm->reset_counter);
 	atomic_set(&vdev->pm->in_reset, 1);
-	ivpu_shutdown(vdev);
+	ivpu_prepare_for_reset(vdev);
+	ivpu_hw_reset(vdev);
 	ivpu_pm_prepare_cold_boot(vdev);
 	ivpu_jobs_abort_all(vdev);
 	ivpu_dbg(vdev, PM, "Pre-reset done.\n");
-- 
2.25.1