Re: [Intel-gfx] [PATCH v9 12/17] drm/i915/pxp: Enable PXP power management

[Rodrigo Vivi <rodrigo.vivi@intel.com>]

On Fri, Sep 10, 2021 at 08:36:22AM -0700, Daniele Ceraolo Spurio wrote:
> From: "Huang, Sean Z" <sean.z.huang@intel.com>
> 
> During the power event S3+ sleep/resume, hardware will lose all the
> encryption keys for every hardware session, even though the
> session state might still be marked as alive after resume. Therefore,
> we should consider the session as dead on suspend and invalidate all the
> objects. The session will be automatically restarted on the first
> protected submission on resume.
> 
> v2: runtime suspend also invalidates the keys
> v3: fix return codes, simplify rpm ops (Chris), use the new worker func
> v4: invalidate the objects on suspend, don't re-create the arb sesson on
> resume (delayed to first submission).
> v5: move irq changes back to irq patch (Rodrigo)
> v6: drop invalidation in runtime suspend (Rodrigo)
> 
> Signed-off-by: Huang, Sean Z <sean.z.huang@intel.com>
> Signed-off-by: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
> Cc: Chris Wilson <chris@chris-wilson.co.uk>
> Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>

ops, I had missed this patch. Sorry
and thanks Alan for the ping.

> ---
>  drivers/gpu/drm/i915/Makefile                |  1 +
>  drivers/gpu/drm/i915/gt/intel_gt_pm.c        | 15 ++++++-
>  drivers/gpu/drm/i915/i915_drv.c              |  2 +
>  drivers/gpu/drm/i915/pxp/intel_pxp_irq.c     |  1 +
>  drivers/gpu/drm/i915/pxp/intel_pxp_pm.c      | 46 ++++++++++++++++++++
>  drivers/gpu/drm/i915/pxp/intel_pxp_pm.h      | 23 ++++++++++
>  drivers/gpu/drm/i915/pxp/intel_pxp_session.c | 38 +++++++++++-----
>  drivers/gpu/drm/i915/pxp/intel_pxp_tee.c     |  9 ++++
>  8 files changed, 124 insertions(+), 11 deletions(-)
>  create mode 100644 drivers/gpu/drm/i915/pxp/intel_pxp_pm.c
>  create mode 100644 drivers/gpu/drm/i915/pxp/intel_pxp_pm.h
> 
> diff --git a/drivers/gpu/drm/i915/Makefile b/drivers/gpu/drm/i915/Makefile
> index b22b8c195bb8..366e82cec44d 100644
> --- a/drivers/gpu/drm/i915/Makefile
> +++ b/drivers/gpu/drm/i915/Makefile
> @@ -286,6 +286,7 @@ i915-$(CONFIG_DRM_I915_PXP) += \
>  	pxp/intel_pxp.o \
>  	pxp/intel_pxp_cmd.o \
>  	pxp/intel_pxp_irq.o \
> +	pxp/intel_pxp_pm.o \
>  	pxp/intel_pxp_session.o \
>  	pxp/intel_pxp_tee.o
>  
> diff --git a/drivers/gpu/drm/i915/gt/intel_gt_pm.c b/drivers/gpu/drm/i915/gt/intel_gt_pm.c
> index dea8e2479897..b47a8d8f1bb5 100644
> --- a/drivers/gpu/drm/i915/gt/intel_gt_pm.c
> +++ b/drivers/gpu/drm/i915/gt/intel_gt_pm.c
> @@ -18,6 +18,7 @@
>  #include "intel_rc6.h"
>  #include "intel_rps.h"
>  #include "intel_wakeref.h"
> +#include "pxp/intel_pxp_pm.h"
>  
>  static void user_forcewake(struct intel_gt *gt, bool suspend)
>  {
> @@ -262,6 +263,8 @@ int intel_gt_resume(struct intel_gt *gt)
>  
>  	intel_uc_resume(&gt->uc);
>  
> +	intel_pxp_resume(&gt->pxp);
> +
>  	user_forcewake(gt, false);
>  
>  out_fw:
> @@ -296,6 +299,7 @@ void intel_gt_suspend_prepare(struct intel_gt *gt)
>  	user_forcewake(gt, true);
>  	wait_for_suspend(gt);
>  
> +	intel_pxp_suspend(&gt->pxp, false);
>  	intel_uc_suspend(&gt->uc);
>  }
>  
> @@ -346,6 +350,7 @@ void intel_gt_suspend_late(struct intel_gt *gt)
>  
>  void intel_gt_runtime_suspend(struct intel_gt *gt)
>  {
> +	intel_pxp_suspend(&gt->pxp, true);

We should actually remove this from here

>  	intel_uc_runtime_suspend(&gt->uc);
>  
>  	GT_TRACE(gt, "\n");
> @@ -353,11 +358,19 @@ void intel_gt_runtime_suspend(struct intel_gt *gt)
>  
>  int intel_gt_runtime_resume(struct intel_gt *gt)
>  {
> +	int ret;
> +
>  	GT_TRACE(gt, "\n");
>  	intel_gt_init_swizzling(gt);
>  	intel_ggtt_restore_fences(gt->ggtt);
>  
> -	return intel_uc_runtime_resume(&gt->uc);
> +	ret = intel_uc_runtime_resume(&gt->uc);
> +	if (ret)
> +		return ret;
> +
> +	intel_pxp_resume(&gt->pxp);

And from here...

> +
> +	return 0;
>  }
>  
>  static ktime_t __intel_gt_get_awake_time(const struct intel_gt *gt)
> diff --git a/drivers/gpu/drm/i915/i915_drv.c b/drivers/gpu/drm/i915/i915_drv.c
> index 59fb4c710c8c..d5bcc70a22d4 100644
> --- a/drivers/gpu/drm/i915/i915_drv.c
> +++ b/drivers/gpu/drm/i915/i915_drv.c
> @@ -67,6 +67,8 @@
>  #include "gt/intel_gt_pm.h"
>  #include "gt/intel_rc6.h"
>  
> +#include "pxp/intel_pxp_pm.h"
> +
>  #include "i915_debugfs.h"
>  #include "i915_drv.h"
>  #include "i915_ioc32.h"
> diff --git a/drivers/gpu/drm/i915/pxp/intel_pxp_irq.c b/drivers/gpu/drm/i915/pxp/intel_pxp_irq.c
> index 340f20d130a8..9e5847c653f2 100644
> --- a/drivers/gpu/drm/i915/pxp/intel_pxp_irq.c
> +++ b/drivers/gpu/drm/i915/pxp/intel_pxp_irq.c
> @@ -9,6 +9,7 @@
>  #include "gt/intel_gt_irq.h"
>  #include "i915_irq.h"
>  #include "i915_reg.h"
> +#include "intel_runtime_pm.h"
>  
>  /**
>   * intel_pxp_irq_handler - Handles PXP interrupts.
> diff --git a/drivers/gpu/drm/i915/pxp/intel_pxp_pm.c b/drivers/gpu/drm/i915/pxp/intel_pxp_pm.c
> new file mode 100644
> index 000000000000..23fd86de5a24
> --- /dev/null
> +++ b/drivers/gpu/drm/i915/pxp/intel_pxp_pm.c
> @@ -0,0 +1,46 @@
> +// SPDX-License-Identifier: MIT
> +/*
> + * Copyright(c) 2020 Intel Corporation.
> + */
> +
> +#include "intel_pxp.h"
> +#include "intel_pxp_irq.h"
> +#include "intel_pxp_pm.h"
> +#include "intel_pxp_session.h"
> +
> +void intel_pxp_suspend(struct intel_pxp *pxp, bool runtime)
> +{
> +	if (!intel_pxp_is_enabled(pxp))
> +		return;
> +
> +	pxp->arb_is_valid = false;
> +
> +	/*
> +	 * Contexts using protected objects keep a runtime PM reference, so we
> +	 * can only runtime suspend when all of them have been either closed
> +	 * or banned. Therefore, there is no need to invalidate in that
> +	 * scenario.
> +	 */

and remove this comment

> +	if (!runtime)

and remove the runtime boolean entirely.

> +		intel_pxp_invalidate(pxp);
> +
> +	intel_pxp_fini_hw(pxp);
> +
> +	pxp->hw_state_invalidated = false;
> +}
> +
> +void intel_pxp_resume(struct intel_pxp *pxp)
> +{
> +	if (!intel_pxp_is_enabled(pxp))
> +		return;
> +
> +	/*
> +	 * The PXP component gets automatically unbound when we go into S3 and
> +	 * re-bound after we come out, so in that scenario we can defer the
> +	 * hw init to the bind call.
> +	 */
> +	if (!pxp->pxp_component)
> +		return;
> +
> +	intel_pxp_init_hw(pxp);
> +}
> diff --git a/drivers/gpu/drm/i915/pxp/intel_pxp_pm.h b/drivers/gpu/drm/i915/pxp/intel_pxp_pm.h
> new file mode 100644
> index 000000000000..e6a357996e19
> --- /dev/null
> +++ b/drivers/gpu/drm/i915/pxp/intel_pxp_pm.h
> @@ -0,0 +1,23 @@
> +/* SPDX-License-Identifier: MIT */
> +/*
> + * Copyright(c) 2020, Intel Corporation. All rights reserved.
> + */
> +
> +#ifndef __INTEL_PXP_PM_H__
> +#define __INTEL_PXP_PM_H__
> +
> +#include "i915_drv.h"
> +
> +#ifdef CONFIG_DRM_I915_PXP
> +void intel_pxp_suspend(struct intel_pxp *pxp, bool runtime);
> +void intel_pxp_resume(struct intel_pxp *pxp);
> +#else
> +static inline void intel_pxp_suspend(struct intel_pxp *pxp, bool runtime)
> +{
> +}
> +static inline void intel_pxp_resume(struct intel_pxp *pxp)
> +{
> +}
> +#endif
> +
> +#endif /* __INTEL_PXP_PM_H__ */
> diff --git a/drivers/gpu/drm/i915/pxp/intel_pxp_session.c b/drivers/gpu/drm/i915/pxp/intel_pxp_session.c
> index a95cc443a48d..d02732f04757 100644
> --- a/drivers/gpu/drm/i915/pxp/intel_pxp_session.c
> +++ b/drivers/gpu/drm/i915/pxp/intel_pxp_session.c
> @@ -21,29 +21,36 @@
>  
>  static bool intel_pxp_session_is_in_play(struct intel_pxp *pxp, u32 id)
>  {
> -	struct intel_gt *gt = pxp_to_gt(pxp);
> +	struct intel_uncore *uncore = pxp_to_gt(pxp)->uncore;
>  	intel_wakeref_t wakeref;
>  	u32 sip = 0;
>  
> -	with_intel_runtime_pm(gt->uncore->rpm, wakeref)
> -		sip = intel_uncore_read(gt->uncore, GEN12_KCR_SIP);
> +	/* if we're suspended the session is considered off */
> +	with_intel_runtime_pm_if_in_use(uncore->rpm, wakeref)
> +		sip = intel_uncore_read(uncore, GEN12_KCR_SIP);
>  
>  	return sip & BIT(id);
>  }
>  
>  static int pxp_wait_for_session_state(struct intel_pxp *pxp, u32 id, bool in_play)
>  {
> -	struct intel_gt *gt = pxp_to_gt(pxp);
> +	struct intel_uncore *uncore = pxp_to_gt(pxp)->uncore;
>  	intel_wakeref_t wakeref;
>  	u32 mask = BIT(id);
>  	int ret;
>  
> -	with_intel_runtime_pm(gt->uncore->rpm, wakeref)
> -		ret = intel_wait_for_register(gt->uncore,
> -					      GEN12_KCR_SIP,
> -					      mask,
> -					      in_play ? mask : 0,
> -					      100);
> +	/* if we're suspended the session is considered off */
> +	wakeref = intel_runtime_pm_get_if_in_use(uncore->rpm);
> +	if (!wakeref)
> +		return in_play ? -ENODEV : 0;
> +
> +	ret = intel_wait_for_register(uncore,
> +				      GEN12_KCR_SIP,
> +				      mask,
> +				      in_play ? mask : 0,
> +				      100);
> +
> +	intel_runtime_pm_put(uncore->rpm, wakeref);
>  
>  	return ret;
>  }
> @@ -135,6 +142,7 @@ void intel_pxp_session_work(struct work_struct *work)
>  {
>  	struct intel_pxp *pxp = container_of(work, typeof(*pxp), session_work);
>  	struct intel_gt *gt = pxp_to_gt(pxp);
> +	intel_wakeref_t wakeref;
>  	u32 events = 0;
>  
>  	spin_lock_irq(&gt->irq_lock);
> @@ -147,6 +155,14 @@ void intel_pxp_session_work(struct work_struct *work)
>  	if (events & PXP_INVAL_REQUIRED)
>  		intel_pxp_invalidate(pxp);
>  
> +	/*
> +	 * If we're processing an event while suspending then don't bother,
> +	 * we're going to re-init everything on resume anyway.
> +	 */
> +	wakeref = intel_runtime_pm_get_if_in_use(gt->uncore->rpm);
> +	if (!wakeref)
> +		return;
> +
>  	if (events & PXP_TERMINATION_REQUEST) {
>  		events &= ~PXP_TERMINATION_COMPLETE;
>  		pxp_terminate(pxp);
> @@ -154,4 +170,6 @@ void intel_pxp_session_work(struct work_struct *work)
>  
>  	if (events & PXP_TERMINATION_COMPLETE)
>  		pxp_terminate_complete(pxp);
> +
> +	intel_runtime_pm_put(gt->uncore->rpm, wakeref);
>  }
> diff --git a/drivers/gpu/drm/i915/pxp/intel_pxp_tee.c b/drivers/gpu/drm/i915/pxp/intel_pxp_tee.c
> index 3fc3ddfd02b3..49508f31dcb7 100644
> --- a/drivers/gpu/drm/i915/pxp/intel_pxp_tee.c
> +++ b/drivers/gpu/drm/i915/pxp/intel_pxp_tee.c
> @@ -78,16 +78,25 @@ static int intel_pxp_tee_io_message(struct intel_pxp *pxp,
>  static int i915_pxp_tee_component_bind(struct device *i915_kdev,
>  				       struct device *tee_kdev, void *data)
>  {
> +	struct drm_i915_private *i915 = kdev_to_i915(i915_kdev);
>  	struct intel_pxp *pxp = i915_dev_to_pxp(i915_kdev);
> +	intel_wakeref_t wakeref;
>  
>  	mutex_lock(&pxp->tee_mutex);
>  	pxp->pxp_component = data;
>  	pxp->pxp_component->tee_dev = tee_kdev;
>  	mutex_unlock(&pxp->tee_mutex);
>  
> +	/* if we are suspended, the HW will be re-initialized on resume */
> +	wakeref = intel_runtime_pm_get_if_in_use(&i915->runtime_pm);
> +	if (!wakeref)
> +		return 0;
> +
>  	/* the component is required to fully start the PXP HW */
>  	intel_pxp_init_hw(pxp);
>  
> +	intel_runtime_pm_put(&i915->runtime_pm, wakeref);
> +
>  	return 0;
>  }
>  
> -- 
> 2.25.1
>