[PATCH v6 2/7] drm/amd: Add concept of running prepare_suspend() sequence for IP blocks

[Mario Limonciello]

If any IP blocks allocate memory during their hw_fini() sequence
this can cause the suspend to fail under memory pressure.  Introduce
a new phase that IP blocks can use to allocate memory before suspend
starts so that it can potentially be evicted into swap instead.

Reviewed-by: Christian König <christian.koe...@amd.com>
Signed-off-by: Mario Limonciello <mario.limoncie...@amd.com>
---
 drivers/gpu/drm/amd/amdgpu/amdgpu_device.c | 12 +++++++++++-
 drivers/gpu/drm/amd/include/amd_shared.h   |  1 +
 2 files changed, 12 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c 
b/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
index 0a7cc9107f07..0f98f720d9ca 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
@@ -4348,7 +4348,7 @@ static int amdgpu_device_evict_resources(struct 
amdgpu_device *adev)
 int amdgpu_device_prepare(struct drm_device *dev)
 {
        struct amdgpu_device *adev = drm_to_adev(dev);
-       int r;
+       int i, r;
 
        if (dev->switch_power_state == DRM_SWITCH_POWER_OFF)
                return 0;
@@ -4358,6 +4358,16 @@ int amdgpu_device_prepare(struct drm_device *dev)
        if (r)
                return r;
 
+       for (i = 0; i < adev->num_ip_blocks; i++) {
+               if (!adev->ip_blocks[i].status.valid)
+                       continue;
+               if (!adev->ip_blocks[i].version->funcs->prepare_suspend)
+                       continue;
+               r = adev->ip_blocks[i].version->funcs->prepare_suspend((void 
*)adev);
+               if (r)
+                       return r;
+       }
+
        return 0;
 }
 
diff --git a/drivers/gpu/drm/amd/include/amd_shared.h 
b/drivers/gpu/drm/amd/include/amd_shared.h
index ce75351204bb..98e60bc868dd 100644
--- a/drivers/gpu/drm/amd/include/amd_shared.h
+++ b/drivers/gpu/drm/amd/include/amd_shared.h
@@ -299,6 +299,7 @@ struct amd_ip_funcs {
        int (*hw_init)(void *handle);
        int (*hw_fini)(void *handle);
        void (*late_fini)(void *handle);
+       int (*prepare_suspend)(void *handle);
        int (*suspend)(void *handle);
        int (*resume)(void *handle);
        bool (*is_idle)(void *handle);
-- 
2.34.1