On 13-07-2023 20:01, Anshuman Gupta wrote:
> Adding support to control d3cold by using vram_usages metric from
> ttm resource manager.
> When root port is capable of d3cold but xe has disallowed d3cold
> due to vrame_usages above vram_d3ccold_threshol. It is required to
> disable d3cold to avoid any resume failure because root port can
> still transition to d3cold when all of pcie endpoints and
> {upstream, virtual} switch ports will transition to d3hot.
> Also cleaning up the TODO code comment.
>
> v2:
> - Modify d3cold.allowed in xe_pm_d3cold_allowed_toggle. [Riana]
> - Cond changed (total_vram_used_mb < xe->d3cold.vram_threshold)
> according to doc comment.
> v3:
> - Added enum instead of true/flase argument in
> d3cold_toggle(). [Rodrigo]
> - Removed TODO comment. [Rodrigo]
>
> Cc: Rodrigo Vivi <rodrigo.vivi at intel.com>
> Signed-off-by: Anshuman Gupta <anshuman.gupta at intel.com>
> Reviewed-by: Badal Nilawar <badal.nilawar at intel.com>
> Acked-by: Rodrigo Vivi <rodrigo.vivi at intel.com>
> ---
> drivers/gpu/drm/xe/xe_pci.c | 36 +++++++++++++++++++++++++++++++++---
> drivers/gpu/drm/xe/xe_pm.c | 25 +++++++++++++++++++++++++
> drivers/gpu/drm/xe/xe_pm.h | 1 +
> 3 files changed, 59 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/gpu/drm/xe/xe_pci.c b/drivers/gpu/drm/xe/xe_pci.c
> index ce4bdfcbc46d..871868301838 100644
> --- a/drivers/gpu/drm/xe/xe_pci.c
> +++ b/drivers/gpu/drm/xe/xe_pci.c
> @@ -26,6 +26,11 @@
> #include "xe_pm.h"
> #include "xe_step.h"
>
> +enum toggle_d3cold {
> + D3COLD_DISABLE,
> + D3COLD_ENABLE,
> +};
> +
> struct xe_subplatform_desc {
> enum xe_subplatform subplatform;
> const char *name;
> @@ -754,6 +759,28 @@ static int xe_pci_resume(struct device *dev)
> return 0;
> }
>
> +static void d3cold_toggle(struct pci_dev *pdev, enum toggle_d3cold toggle)
> +{
> + struct xe_device *xe = pdev_to_xe_device(pdev);
> + struct pci_dev *root_pdev;
> +
> + if (!xe->d3cold.capable)
> + return;
> +
> + root_pdev = pcie_find_root_port(pdev);
> + if (!root_pdev)
> + return;
> +
> + switch (toggle) {
> + case D3COLD_DISABLE:
> + pci_d3cold_disable(root_pdev);
> + break;
> + case D3COLD_ENABLE:
> + pci_d3cold_enable(root_pdev);
> + break;
> + }
> +}
> +
> static int xe_pci_runtime_suspend(struct device *dev)
> {
> struct pci_dev *pdev = to_pci_dev(dev);
> @@ -771,6 +798,7 @@ static int xe_pci_runtime_suspend(struct device *dev)
> pci_ignore_hotplug(pdev);
> pci_set_power_state(pdev, PCI_D3cold);
> } else {
> + d3cold_toggle(pdev, D3COLD_DISABLE);
> pci_set_power_state(pdev, PCI_D3hot);
> }
>
> @@ -795,6 +823,8 @@ static int xe_pci_runtime_resume(struct device *dev)
> return err;
>
> pci_set_master(pdev);
> + } else {
> + d3cold_toggle(pdev, D3COLD_ENABLE);
> }
>
> return xe_pm_runtime_resume(xe);
> @@ -808,15 +838,15 @@ static int xe_pci_runtime_idle(struct device *dev)
> if (!xe->d3cold.capable) {
> xe->d3cold.allowed = false;
> } else {
> + xe_pm_d3cold_allowed_toggle(xe);
> +
> /*
> * TODO: d3cold should be allowed (true) if
> * (IS_DGFX(xe) && !xe_device_mem_access_ongoing(xe))
> * but maybe include some other conditions. So, before
> * we can re-enable the D3cold, we need to:
> * 1. rewrite the VRAM save / restore to avoid buffer object locks
> - * 2. block D3cold if we have a big amount of device memory in use
> - * in order to reduce the latency.
> - * 3. at resume, detect if we really lost power and avoid memory
> + * 2. at resume, detect if we really lost power and avoid memory
> * restoration if we were only up to d3cold I think avoid restoration if d3hot?
Regards,
Badal
> */
> xe->d3cold.allowed = false;
> diff --git a/drivers/gpu/drm/xe/xe_pm.c b/drivers/gpu/drm/xe/xe_pm.c
> index 07e204990aa9..c732317b55cb 100644
> --- a/drivers/gpu/drm/xe/xe_pm.c
> +++ b/drivers/gpu/drm/xe/xe_pm.c
> @@ -292,3 +292,28 @@ int xe_pm_set_vram_threshold(struct xe_device *xe, u32 threshold)
>
> return 0;
> }
> +
> +void xe_pm_d3cold_allowed_toggle(struct xe_device *xe)
> +{
> + struct ttm_resource_manager *man;
> + u32 total_vram_used_mb = 0;
> + u64 vram_used;
> + int i;
> +
> + for (i = XE_PL_VRAM0; i <= XE_PL_VRAM1; ++i) {
> + man = ttm_manager_type(&xe->ttm, i);
> + if (man) {
> + vram_used = ttm_resource_manager_usage(man);
> + total_vram_used_mb += DIV_ROUND_UP_ULL(vram_used, 1024 * 1024);
> + }
> + }
> +
> + mutex_lock(&xe->d3cold.lock);
> +
> + if (total_vram_used_mb < xe->d3cold.vram_threshold)
> + xe->d3cold.allowed = true;
> + else
> + xe->d3cold.allowed = false;
> +
> + mutex_unlock(&xe->d3cold.lock);
> +}
> diff --git a/drivers/gpu/drm/xe/xe_pm.h b/drivers/gpu/drm/xe/xe_pm.h
> index bbd91a5855cd..ee30cf025f64 100644
> --- a/drivers/gpu/drm/xe/xe_pm.h
> +++ b/drivers/gpu/drm/xe/xe_pm.h
> @@ -25,5 +25,6 @@ bool xe_pm_runtime_resume_if_suspended(struct xe_device *xe);
> int xe_pm_runtime_get_if_active(struct xe_device *xe);
> void xe_pm_assert_unbounded_bridge(struct xe_device *xe);
> int xe_pm_set_vram_threshold(struct xe_device *xe, u32 threshold);
> +void xe_pm_d3cold_allowed_toggle(struct xe_device *xe);
>
> #endif