drm/amdgpu: add irq domain support

Hardware blocks on the GPU like ACP generate interrupts in
the GPU interrupt controller, but are driven by a separate
driver.  Add an irq domain to the GPU driver so that
blocks like ACP can register a Linux interrupt.

Acked-by: Dave Airlie <airlied@redhat.com>
Acked-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

6 files changed, 136 insertions, 8 deletions

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_irq.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_irq.c
index 7c42ff670080..3006182c5d0d 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_irq.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_irq.c
@@ -312,6 +312,7 @@ int amdgpu_irq_add_id(struct amdgpu_device *adev, unsigned src_id,
         }
 
         adev->irq.sources[src_id] = source;
+
         return 0;
 }
 
@@ -335,15 +336,19 @@ void amdgpu_irq_dispatch(struct amdgpu_device *adev,
                 return;
         }
 
-        src = adev->irq.sources[src_id];
-        if (!src) {
-                DRM_DEBUG("Unhandled interrupt src_id: %d\n", src_id);
-                return;
-        }
+        if (adev->irq.virq[src_id]) {
+                generic_handle_irq(irq_find_mapping(adev->irq.domain, src_id));
+        } else {
+                src = adev->irq.sources[src_id];
+                if (!src) {
+                        DRM_DEBUG("Unhandled interrupt src_id: %d\n", src_id);
+                        return;
+                }
 
-        r = src->funcs->process(adev, src, entry);
-        if (r)
-                DRM_ERROR("error processing interrupt (%d)\n", r);
+                r = src->funcs->process(adev, src, entry);
+                if (r)
+                        DRM_ERROR("error processing interrupt (%d)\n", r);
+        }
 }
 
 /**
@@ -461,3 +466,90 @@ bool amdgpu_irq_enabled(struct amdgpu_device *adev, struct amdgpu_irq_src *src,
 
         return !!atomic_read(&src->enabled_types[type]);
 }
+
+/* gen irq */
+static void amdgpu_irq_mask(struct irq_data *irqd)
+{
+        /* XXX */
+}
+
+static void amdgpu_irq_unmask(struct irq_data *irqd)
+{
+        /* XXX */
+}
+
+static struct irq_chip amdgpu_irq_chip = {
+        .name = "amdgpu-ih",
+        .irq_mask = amdgpu_irq_mask,
+        .irq_unmask = amdgpu_irq_unmask,
+};
+
+static int amdgpu_irqdomain_map(struct irq_domain *d,
+                                unsigned int irq, irq_hw_number_t hwirq)
+{
+        if (hwirq >= AMDGPU_MAX_IRQ_SRC_ID)
+                return -EPERM;
+
+        irq_set_chip_and_handler(irq,
+                                 &amdgpu_irq_chip, handle_simple_irq);
+        return 0;
+}
+
+static struct irq_domain_ops amdgpu_hw_irqdomain_ops = {
+        .map = amdgpu_irqdomain_map,
+};
+
+/**
+ * amdgpu_irq_add_domain - create a linear irq domain
+ *
+ * @adev: amdgpu device pointer
+ *
+ * Create an irq domain for GPU interrupt sources
+ * that may be driven by another driver (e.g., ACP).
+ */
+int amdgpu_irq_add_domain(struct amdgpu_device *adev)
+{
+        adev->irq.domain = irq_domain_add_linear(NULL, AMDGPU_MAX_IRQ_SRC_ID,
+                                                 &amdgpu_hw_irqdomain_ops, adev);
+        if (!adev->irq.domain) {
+                DRM_ERROR("GPU irq add domain failed\n");
+                return -ENODEV;
+        }
+
+        return 0;
+}
+
+/**
+ * amdgpu_irq_remove_domain - remove the irq domain
+ *
+ * @adev: amdgpu device pointer
+ *
+ * Remove the irq domain for GPU interrupt sources
+ * that may be driven by another driver (e.g., ACP).
+ */
+void amdgpu_irq_remove_domain(struct amdgpu_device *adev)
+{
+        if (adev->irq.domain) {
+                irq_domain_remove(adev->irq.domain);
+                adev->irq.domain = NULL;
+        }
+}
+
+/**
+ * amdgpu_irq_create_mapping - create a mapping between a domain irq and a
+ *                             Linux irq
+ *
+ * @adev: amdgpu device pointer
+ * @src_id: IH source id
+ *
+ * Create a mapping between a domain irq (GPU IH src id) and a Linux irq
+ * Use this for components that generate a GPU interrupt, but are driven
+ * by a different driver (e.g., ACP).
+ * Returns the Linux irq.
+ */
+unsigned amdgpu_irq_create_mapping(struct amdgpu_device *adev, unsigned src_id)
+{
+        adev->irq.virq[src_id] = irq_create_mapping(adev->irq.domain, src_id);
+
+        return adev->irq.virq[src_id];
+}
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_irq.h b/drivers/gpu/drm/amd/amdgpu/amdgpu_irq.h
index 17b01aef4278..e124b59f39c1 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_irq.h
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_irq.h
@@ -24,6 +24,7 @@
 #ifndef __AMDGPU_IRQ_H__
 #define __AMDGPU_IRQ_H__
 
+#include <linux/irqdomain.h>
 #include "amdgpu_ih.h"
 
 #define AMDGPU_MAX_IRQ_SRC_ID   0x100
@@ -65,6 +66,10 @@ struct amdgpu_irq {
         /* interrupt ring */
         struct amdgpu_ih_ring           ih;
         const struct amdgpu_ih_funcs    *ih_funcs;
+
+        /* gen irq stuff */
+        struct irq_domain               *domain; /* GPU irq controller domain */
+        unsigned                        virq[AMDGPU_MAX_IRQ_SRC_ID];
 };
 
 void amdgpu_irq_preinstall(struct drm_device *dev);
@@ -90,4 +95,8 @@ int amdgpu_irq_put(struct amdgpu_device *adev, struct amdgpu_irq_src *src,
 bool amdgpu_irq_enabled(struct amdgpu_device *adev, struct amdgpu_irq_src *src,
                         unsigned type);
 
+int amdgpu_irq_add_domain(struct amdgpu_device *adev);
+void amdgpu_irq_remove_domain(struct amdgpu_device *adev);
+unsigned amdgpu_irq_create_mapping(struct amdgpu_device *adev, unsigned src_id);
+
 #endif
diff --git a/drivers/gpu/drm/amd/amdgpu/cik_ih.c b/drivers/gpu/drm/amd/amdgpu/cik_ih.c
index 8993c50cb89f..30c9b3beeef9 100644
--- a/drivers/gpu/drm/amd/amdgpu/cik_ih.c
+++ b/drivers/gpu/drm/amd/amdgpu/cik_ih.c
@@ -274,6 +274,11 @@ static void cik_ih_set_rptr(struct amdgpu_device *adev)
 static int cik_ih_early_init(void *handle)
 {
         struct amdgpu_device *adev = (struct amdgpu_device *)handle;
+        int ret;
+
+        ret = amdgpu_irq_add_domain(adev);
+        if (ret)
+                return ret;
 
         cik_ih_set_interrupt_funcs(adev);
 
@@ -300,6 +305,7 @@ static int cik_ih_sw_fini(void *handle)
 
         amdgpu_irq_fini(adev);
         amdgpu_ih_ring_fini(adev);
+        amdgpu_irq_remove_domain(adev);
 
         return 0;
 }
diff --git a/drivers/gpu/drm/amd/amdgpu/cz_ih.c b/drivers/gpu/drm/amd/amdgpu/cz_ih.c
index bc751bfbcae2..c79638f8e732 100644
--- a/drivers/gpu/drm/amd/amdgpu/cz_ih.c
+++ b/drivers/gpu/drm/amd/amdgpu/cz_ih.c
@@ -253,8 +253,14 @@ static void cz_ih_set_rptr(struct amdgpu_device *adev)
 static int cz_ih_early_init(void *handle)
 {
         struct amdgpu_device *adev = (struct amdgpu_device *)handle;
+        int ret;
+
+        ret = amdgpu_irq_add_domain(adev);
+        if (ret)
+                return ret;
 
         cz_ih_set_interrupt_funcs(adev);
+
         return 0;
 }
 
@@ -278,6 +284,7 @@ static int cz_ih_sw_fini(void *handle)
 
         amdgpu_irq_fini(adev);
         amdgpu_ih_ring_fini(adev);
+        amdgpu_irq_remove_domain(adev);
 
         return 0;
 }
diff --git a/drivers/gpu/drm/amd/amdgpu/iceland_ih.c b/drivers/gpu/drm/amd/amdgpu/iceland_ih.c
index 779532d350ff..679e7394a495 100644
--- a/drivers/gpu/drm/amd/amdgpu/iceland_ih.c
+++ b/drivers/gpu/drm/amd/amdgpu/iceland_ih.c
@@ -253,8 +253,14 @@ static void iceland_ih_set_rptr(struct amdgpu_device *adev)
 static int iceland_ih_early_init(void *handle)
 {
         struct amdgpu_device *adev = (struct amdgpu_device *)handle;
+        int ret;
+
+        ret = amdgpu_irq_add_domain(adev);
+        if (ret)
+                return ret;
 
         iceland_ih_set_interrupt_funcs(adev);
+
         return 0;
 }
 
@@ -278,6 +284,7 @@ static int iceland_ih_sw_fini(void *handle)
 
         amdgpu_irq_fini(adev);
         amdgpu_ih_ring_fini(adev);
+        amdgpu_irq_remove_domain(adev);
 
         return 0;
 }
diff --git a/drivers/gpu/drm/amd/amdgpu/tonga_ih.c b/drivers/gpu/drm/amd/amdgpu/tonga_ih.c
index 743c372837aa..b6f7d7bff929 100644
--- a/drivers/gpu/drm/amd/amdgpu/tonga_ih.c
+++ b/drivers/gpu/drm/amd/amdgpu/tonga_ih.c
@@ -273,8 +273,14 @@ static void tonga_ih_set_rptr(struct amdgpu_device *adev)
 static int tonga_ih_early_init(void *handle)
 {
         struct amdgpu_device *adev = (struct amdgpu_device *)handle;
+        int ret;
+
+        ret = amdgpu_irq_add_domain(adev);
+        if (ret)
+                return ret;
 
         tonga_ih_set_interrupt_funcs(adev);
+
         return 0;
 }
 
@@ -301,6 +307,7 @@ static int tonga_ih_sw_fini(void *handle)
 
         amdgpu_irq_fini(adev);
         amdgpu_ih_ring_fini(adev);
+        amdgpu_irq_add_domain(adev);
 
         return 0;
 }