[AMD Public Use] Hi Alex,
By checking the document and source code of pci_pm_prepare(), it seems the prepare callback provided by device driver is optional, not must. - even without the prepare callback provide by device driver, the ->prepare of subsystem/bus can still return positive number(1) - the result of the prepare callback provide by device driver may be not honored unless DPM_FLAG_SMART_PREPARE is set. BR Evan -----Original Message----- From: amd-gfx <[email protected]> On Behalf Of Alex Deucher Sent: Tuesday, March 9, 2021 12:10 PM To: [email protected] Cc: Deucher, Alexander <[email protected]> Subject: [PATCH 1/7] drm/amdgpu: add a dev_pm_ops prepare callback (v2) as per: https://nam11.safelinks.protection.outlook.com/?url=https%3A%2F%2Fwww.kernel.org%2Fdoc%2Fhtml%2Flatest%2Fdriver-api%2Fpm%2Fdevices.html&data=04%7C01%7Cevan.quan%40amd.com%7C6e3b5c960f1145c79e1c08d8e2b14a95%7C3dd8961fe4884e608e11a82d994e183d%7C0%7C0%7C637508598383549752%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C1000&sdata=hLOdKKeO7JMk5kU5gmYSrBD53LhsT8vtEH3UivKjx48%3D&reserved=0 The prepare callback is required to support the DPM_FLAG_SMART_SUSPEND driver flag. This allows runtime pm to auto complete when the system goes into suspend avoiding a wake up on suspend and on resume. Apply this for hybrid gfx and BOCO systems where d3cold is provided by the ACPI platform. v2: check if device is runtime suspended in prepare. Signed-off-by: Alex Deucher <[email protected]> --- drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c | 24 ++++++++++++++++++++++++ 1 file changed, 24 insertions(+) diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c index aecf7baf219a..8d4fbee01011 100644 --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c @@ -36,6 +36,7 @@ #include <linux/vga_switcheroo.h> #include <drm/drm_probe_helper.h> #include <linux/mmu_notifier.h> +#include <linux/suspend.h> #include "amdgpu.h" #include "amdgpu_irq.h" @@ -1293,6 +1294,27 @@ amdgpu_pci_shutdown(struct pci_dev *pdev) adev->mp1_state = PP_MP1_STATE_NONE; } +static int amdgpu_pmops_prepare(struct device *dev) { + struct drm_device *drm_dev = dev_get_drvdata(dev); + + /* Return a positive number here so + * DPM_FLAG_SMART_SUSPEND works properly + */ + if ((amdgpu_device_supports_atpx(drm_dev) && + amdgpu_is_atpx_hybrid()) || + amdgpu_device_supports_boco(drm_dev)) + return pm_runtime_suspended(dev) && + pm_suspend_via_firmware(); + + return 0; +} + +static void amdgpu_pmops_complete(struct device *dev) { + /* nothing to do */ +} + static int amdgpu_pmops_suspend(struct device *dev) { struct drm_device *drm_dev = dev_get_drvdata(dev); @@ -1511,6 +1533,8 @@ long amdgpu_drm_ioctl(struct file *filp, } static const struct dev_pm_ops amdgpu_pm_ops = { + .prepare = amdgpu_pmops_prepare, + .complete = amdgpu_pmops_complete, .suspend = amdgpu_pmops_suspend, .resume = amdgpu_pmops_resume, .freeze = amdgpu_pmops_freeze, -- 2.29.2 _______________________________________________ amd-gfx mailing list [email protected] https://nam11.safelinks.protection.outlook.com/?url=https%3A%2F%2Flists.freedesktop.org%2Fmailman%2Flistinfo%2Famd-gfx&data=04%7C01%7Cevan.quan%40amd.com%7C6e3b5c960f1145c79e1c08d8e2b14a95%7C3dd8961fe4884e608e11a82d994e183d%7C0%7C0%7C637508598383559745%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C1000&sdata=6PfggZhs61N3RO6DKAODOOfKappXUnswvHRXgSHJ%2FtA%3D&reserved=0 _______________________________________________ amd-gfx mailing list [email protected] https://lists.freedesktop.org/mailman/listinfo/amd-gfx
