[PATCH v2 04/11] drm/panthor: Extend the IRQ logic to allow fast/hard IRQ handlers

[Boris Brezillon <boris.brezillon@collabora.com>]

All drivers except panthor signal their fences from their interrupt
handler to minimize latency. We could do the same from the threaded
handler, but the latency is still quite high in that case, so let's
allow components to choose the context they want their IRQ handler
to run in by exposing support for custom hard handlers.

Reviewed-by: Liviu Dudau <liviu.dudau@arm.com>
Reviewed-by: Steven Price <steven.price@arm.com>
Signed-off-by: Boris Brezillon <boris.brezillon@collabora.com>
---
 drivers/gpu/drm/panthor/panthor_device.h | 11 ++++++++---
 drivers/gpu/drm/panthor/panthor_fw.c     |  1 +
 drivers/gpu/drm/panthor/panthor_gpu.c    |  1 +
 drivers/gpu/drm/panthor/panthor_mmu.c    |  1 +
 drivers/gpu/drm/panthor/panthor_pwr.c    |  1 +
 5 files changed, 12 insertions(+), 3 deletions(-)

diff --git a/drivers/gpu/drm/panthor/panthor_device.h b/drivers/gpu/drm/panthor/panthor_device.h
index 393fcda73d88..1aaf06df875b 100644
--- a/drivers/gpu/drm/panthor/panthor_device.h
+++ b/drivers/gpu/drm/panthor/panthor_device.h
@@ -672,6 +672,7 @@ static inline void panthor_irq_disable_events(struct panthor_irq *pirq, u32 mask
 static inline int
 panthor_irq_request(struct panthor_device *ptdev, struct panthor_irq *pirq,
 		    int irq, u32 mask, void __iomem *iomem, const char *name,
+		    irqreturn_t (*raw_handler)(int, void *data),
 		    irqreturn_t (*threaded_handler)(int, void *data))
 {
 	const char *full_name;
@@ -687,9 +688,13 @@ panthor_irq_request(struct panthor_device *ptdev, struct panthor_irq *pirq,
 		return -ENOMEM;
 
 	panthor_irq_resume(pirq);
-	return devm_request_threaded_irq(ptdev->base.dev, irq,
-					 panthor_irq_default_raw_handler,
-					 threaded_handler,
+
+	if (!threaded_handler) {
+		return devm_request_irq(ptdev->base.dev, irq, raw_handler,
+					IRQF_SHARED, full_name, pirq);
+	}
+
+	return devm_request_threaded_irq(ptdev->base.dev, irq, raw_handler, threaded_handler,
 					 IRQF_SHARED, full_name, pirq);
 }
 
diff --git a/drivers/gpu/drm/panthor/panthor_fw.c b/drivers/gpu/drm/panthor/panthor_fw.c
index eaf599b0a887..8239a6951569 100644
--- a/drivers/gpu/drm/panthor/panthor_fw.c
+++ b/drivers/gpu/drm/panthor/panthor_fw.c
@@ -1483,6 +1483,7 @@ int panthor_fw_init(struct panthor_device *ptdev)
 
 	ret = panthor_irq_request(ptdev, &fw->irq, irq, 0,
 				  ptdev->iomem + JOB_INT_BASE, "job",
+				  panthor_irq_default_raw_handler,
 				  panthor_job_irq_threaded_handler);
 	if (ret) {
 		drm_err(&ptdev->base, "failed to request job irq");
diff --git a/drivers/gpu/drm/panthor/panthor_gpu.c b/drivers/gpu/drm/panthor/panthor_gpu.c
index ce208e384762..d0be758ea3e1 100644
--- a/drivers/gpu/drm/panthor/panthor_gpu.c
+++ b/drivers/gpu/drm/panthor/panthor_gpu.c
@@ -177,6 +177,7 @@ int panthor_gpu_init(struct panthor_device *ptdev)
 	ret = panthor_irq_request(ptdev, &ptdev->gpu->irq, irq,
 				  GPU_INTERRUPTS_MASK,
 				  ptdev->iomem + GPU_INT_BASE, "gpu",
+				  panthor_irq_default_raw_handler,
 				  panthor_gpu_irq_threaded_handler);
 	if (ret)
 		return ret;
diff --git a/drivers/gpu/drm/panthor/panthor_mmu.c b/drivers/gpu/drm/panthor/panthor_mmu.c
index 375022fb3fd8..2955b8baa2e2 100644
--- a/drivers/gpu/drm/panthor/panthor_mmu.c
+++ b/drivers/gpu/drm/panthor/panthor_mmu.c
@@ -3266,6 +3266,7 @@ int panthor_mmu_init(struct panthor_device *ptdev)
 	ret = panthor_irq_request(ptdev, &mmu->irq, irq,
 				  panthor_mmu_fault_mask(ptdev, ~0),
 				  ptdev->iomem + MMU_INT_BASE, "mmu",
+				  panthor_irq_default_raw_handler,
 				  panthor_mmu_irq_threaded_handler);
 	if (ret)
 		return ret;
diff --git a/drivers/gpu/drm/panthor/panthor_pwr.c b/drivers/gpu/drm/panthor/panthor_pwr.c
index 80cf78007896..1efb7f3482ba 100644
--- a/drivers/gpu/drm/panthor/panthor_pwr.c
+++ b/drivers/gpu/drm/panthor/panthor_pwr.c
@@ -491,6 +491,7 @@ int panthor_pwr_init(struct panthor_device *ptdev)
 	err = panthor_irq_request(
 		ptdev, &pwr->irq, irq, PWR_INTERRUPTS_MASK,
 		pwr->iomem + PWR_INT_BASE, "pwr",
+		panthor_irq_default_raw_handler,
 		panthor_pwr_irq_threaded_handler);
 	if (err)
 		return err;

-- 
2.54.0