Re: [PATCH v3] drm/i915/pxp: Optimize GET_PARAM:PXP_STATUS

["Ceraolo Spurio, Daniele" <daniele.ceraolospurio@xxxxxxxxx>]

On 6/29/2023 6:44 PM, Alan Previn wrote:
> After recent discussions with Mesa folks, it was requested
> that we optimize i915's GET_PARAM for the PXP_STATUS without
> changing the UAPI spec.
>
> Add these additional optimizations:
>     - If any PXP initializatoin flow failed, then ensure that
>       we catch it so that we can change the returned PXP_STATUS
>       from "2" (i.e. 'PXP is supported but not yet ready')
>       to "-ENODEV". This typically should not happen and if it
>       does, we have a platform configuration issue.
>     - If a PXP arbitration session creation event failed
>       due to incorrect firmware version or blocking SOC fusing
>       or blocking BIOS configuration (platform reasons that won't
>       change if we retry), then reflect that blockage by also
>       returning -ENODEV in the GET_PARAM:PXP_STATUS.
>     - GET_PARAM:PXP_STATUS should not wait at all if PXP is
>       supported but non-i915 dependencies (component-driver /
>       firmware) we are still pending to complete the init flows.
>       In this case, just return "2" immediately (i.e. 'PXP is
>       supported but not yet ready').
>
> Difference from prio revs:
>    v2: - Use a #define for the default readiness timeout (Vivaik).
>        - Improve comments around the failing of proxy-init.
>    v1: - Change the commit msg style to be imperative. (Jani)
>        - Rename timeout to timeout_ms. (Jani)
>        - Fix is_fw_err_platform_config to use higher order
>          param (pxp) first. (Jani)
>
> Signed-off-by: Alan Previn <alan.previn.teres.alexis@xxxxxxxxx>
> ---
>   drivers/gpu/drm/i915/gt/uc/intel_gsc_uc.c  | 10 +++++-
>   drivers/gpu/drm/i915/i915_getparam.c       |  2 +-
>   drivers/gpu/drm/i915/pxp/intel_pxp.c       | 40 ++++++++++++++++++----
>   drivers/gpu/drm/i915/pxp/intel_pxp.h       |  2 +-
>   drivers/gpu/drm/i915/pxp/intel_pxp_gsccs.c |  7 ++--
>   drivers/gpu/drm/i915/pxp/intel_pxp_tee.c   |  7 ++--
>   drivers/gpu/drm/i915/pxp/intel_pxp_types.h |  9 +++++
>   7 files changed, 61 insertions(+), 16 deletions(-)
>
> diff --git a/drivers/gpu/drm/i915/gt/uc/intel_gsc_uc.c b/drivers/gpu/drm/i915/gt/uc/intel_gsc_uc.c
> index 034b53a71541..21c2b7cce335 100644
> --- a/drivers/gpu/drm/i915/gt/uc/intel_gsc_uc.c
> +++ b/drivers/gpu/drm/i915/gt/uc/intel_gsc_uc.c
> @@ -62,8 +62,16 @@ static void gsc_work(struct work_struct *work)
>   		}
>   
>   		ret = intel_gsc_proxy_request_handler(gsc);
> -		if (ret)
> +		if (ret) {
> +			if (actions & GSC_ACTION_FW_LOAD) {
> +				/*
> +				 * A failure right after firmware load means the proxy-init
> +				 * step has failed so mark GSC as not usable after this
> +				 */
> +				intel_uc_fw_change_status(&gsc->fw, INTEL_UC_FIRMWARE_LOAD_FAIL);

Note that proxy init can also fail below if the init_done check returns 
false, so the status needs to be changed in both cases.

Daniele

> +			}
>   			goto out_put;
> +		}
>   
>   		/* mark the GSC FW init as done the first time we run this */
>   		if (actions & GSC_ACTION_FW_LOAD) {
> diff --git a/drivers/gpu/drm/i915/i915_getparam.c b/drivers/gpu/drm/i915/i915_getparam.c
> index 890f2b382bee..5c3fec63cb4c 100644
> --- a/drivers/gpu/drm/i915/i915_getparam.c
> +++ b/drivers/gpu/drm/i915/i915_getparam.c
> @@ -109,7 +109,7 @@ int i915_getparam_ioctl(struct drm_device *dev, void *data,
>   			return value;
>   		break;
>   	case I915_PARAM_PXP_STATUS:
> -		value = intel_pxp_get_readiness_status(i915->pxp);
> +		value = intel_pxp_get_readiness_status(i915->pxp, 0);
>   		if (value < 0)
>   			return value;
>   		break;
> diff --git a/drivers/gpu/drm/i915/pxp/intel_pxp.c b/drivers/gpu/drm/i915/pxp/intel_pxp.c
> index bb2e15329f34..e3b47525dc60 100644
> --- a/drivers/gpu/drm/i915/pxp/intel_pxp.c
> +++ b/drivers/gpu/drm/i915/pxp/intel_pxp.c
> @@ -359,22 +359,46 @@ void intel_pxp_end(struct intel_pxp *pxp)
>   	intel_runtime_pm_put(&i915->runtime_pm, wakeref);
>   }
>   
> +static bool pxp_required_fw_failed(struct intel_pxp *pxp)
> +{
> +	if (__intel_uc_fw_status(&pxp->ctrl_gt->uc.huc.fw) == INTEL_UC_FIRMWARE_LOAD_FAIL)
> +		return true;
> +	if (HAS_ENGINE(pxp->ctrl_gt, GSC0) &&
> +	    __intel_uc_fw_status(&pxp->ctrl_gt->uc.gsc.fw) == INTEL_UC_FIRMWARE_LOAD_FAIL)
> +		return true;
> +
> +	return false;
> +}
> +
> +static bool pxp_fw_dependencies_completed(struct intel_pxp *pxp)
> +{
> +	if (HAS_ENGINE(pxp->ctrl_gt, GSC0))
> +		return intel_pxp_gsccs_is_ready_for_sessions(pxp);
> +
> +	return pxp_component_bound(pxp);
> +}
> +
>   /*
>    * this helper is used by both intel_pxp_start and by
>    * the GET_PARAM IOCTL that user space calls. Thus, the
>    * return values here should match the UAPI spec.
>    */
> -int intel_pxp_get_readiness_status(struct intel_pxp *pxp)
> +int intel_pxp_get_readiness_status(struct intel_pxp *pxp, int timeout_ms)
>   {
>   	if (!intel_pxp_is_enabled(pxp))
>   		return -ENODEV;
>   
> -	if (HAS_ENGINE(pxp->ctrl_gt, GSC0)) {
> -		if (wait_for(intel_pxp_gsccs_is_ready_for_sessions(pxp), 250))
> -			return 2;
> -	} else {
> -		if (wait_for(pxp_component_bound(pxp), 250))
> +	if (pxp_required_fw_failed(pxp))
> +		return -ENODEV;
> +
> +	if (pxp->platform_cfg_is_bad)
> +		return -ENODEV;
> +
> +	if (timeout_ms) {
> +		if (wait_for(pxp_fw_dependencies_completed(pxp), timeout_ms))
>   			return 2;
> +	} else if (!pxp_fw_dependencies_completed(pxp)) {
> +		return 2;
>   	}
>   	return 1;
>   }
> @@ -383,11 +407,13 @@ int intel_pxp_get_readiness_status(struct intel_pxp *pxp)
>    * the arb session is restarted from the irq work when we receive the
>    * termination completion interrupt
>    */
> +#define PXP_READINESS_TIMEOUT 250
> +
>   int intel_pxp_start(struct intel_pxp *pxp)
>   {
>   	int ret = 0;
>   
> -	ret = intel_pxp_get_readiness_status(pxp);
> +	ret = intel_pxp_get_readiness_status(pxp, PXP_READINESS_TIMEOUT);
>   	if (ret < 0)
>   		return ret;
>   	else if (ret > 1)
> diff --git a/drivers/gpu/drm/i915/pxp/intel_pxp.h b/drivers/gpu/drm/i915/pxp/intel_pxp.h
> index 17254c3f1267..d9372f6f7797 100644
> --- a/drivers/gpu/drm/i915/pxp/intel_pxp.h
> +++ b/drivers/gpu/drm/i915/pxp/intel_pxp.h
> @@ -26,7 +26,7 @@ void intel_pxp_fini_hw(struct intel_pxp *pxp);
>   void intel_pxp_mark_termination_in_progress(struct intel_pxp *pxp);
>   void intel_pxp_tee_end_arb_fw_session(struct intel_pxp *pxp, u32 arb_session_id);
>   
> -int intel_pxp_get_readiness_status(struct intel_pxp *pxp);
> +int intel_pxp_get_readiness_status(struct intel_pxp *pxp, int timeout_ms);
>   int intel_pxp_get_backend_timeout_ms(struct intel_pxp *pxp);
>   int intel_pxp_start(struct intel_pxp *pxp);
>   void intel_pxp_end(struct intel_pxp *pxp);
> diff --git a/drivers/gpu/drm/i915/pxp/intel_pxp_gsccs.c b/drivers/gpu/drm/i915/pxp/intel_pxp_gsccs.c
> index c7df47364013..97ad58d6aff1 100644
> --- a/drivers/gpu/drm/i915/pxp/intel_pxp_gsccs.c
> +++ b/drivers/gpu/drm/i915/pxp/intel_pxp_gsccs.c
> @@ -17,12 +17,13 @@
>   #include "intel_pxp_types.h"
>   
>   static bool
> -is_fw_err_platform_config(u32 type)
> +is_fw_err_platform_config(struct intel_pxp *pxp, u32 type)
>   {
>   	switch (type) {
>   	case PXP_STATUS_ERROR_API_VERSION:
>   	case PXP_STATUS_PLATFCONFIG_KF1_NOVERIF:
>   	case PXP_STATUS_PLATFCONFIG_KF1_BAD:
> +		pxp->platform_cfg_is_bad = true;
>   		return true;
>   	default:
>   		break;
> @@ -225,7 +226,7 @@ int intel_pxp_gsccs_create_session(struct intel_pxp *pxp,
>   	if (ret) {
>   		drm_err(&i915->drm, "Failed to init session %d, ret=[%d]\n", arb_session_id, ret);
>   	} else if (msg_out.header.status != 0) {
> -		if (is_fw_err_platform_config(msg_out.header.status)) {
> +		if (is_fw_err_platform_config(pxp, msg_out.header.status)) {
>   			drm_info_once(&i915->drm,
>   				      "PXP init-session-%d failed due to BIOS/SOC:0x%08x:%s\n",
>   				      arb_session_id, msg_out.header.status,
> @@ -268,7 +269,7 @@ void intel_pxp_gsccs_end_arb_fw_session(struct intel_pxp *pxp, u32 session_id)
>   		drm_err(&i915->drm, "Failed to inv-stream-key-%u, ret=[%d]\n",
>   			session_id, ret);
>   	} else if (msg_out.header.status != 0) {
> -		if (is_fw_err_platform_config(msg_out.header.status)) {
> +		if (is_fw_err_platform_config(pxp, msg_out.header.status)) {
>   			drm_info_once(&i915->drm,
>   				      "PXP inv-stream-key-%u failed due to BIOS/SOC :0x%08x:%s\n",
>   				      session_id, msg_out.header.status,
> diff --git a/drivers/gpu/drm/i915/pxp/intel_pxp_tee.c b/drivers/gpu/drm/i915/pxp/intel_pxp_tee.c
> index 1ce07d7e8769..1de054126c6d 100644
> --- a/drivers/gpu/drm/i915/pxp/intel_pxp_tee.c
> +++ b/drivers/gpu/drm/i915/pxp/intel_pxp_tee.c
> @@ -20,12 +20,13 @@
>   #include "intel_pxp_types.h"
>   
>   static bool
> -is_fw_err_platform_config(u32 type)
> +is_fw_err_platform_config(struct intel_pxp *pxp, u32 type)
>   {
>   	switch (type) {
>   	case PXP_STATUS_ERROR_API_VERSION:
>   	case PXP_STATUS_PLATFCONFIG_KF1_NOVERIF:
>   	case PXP_STATUS_PLATFCONFIG_KF1_BAD:
> +		pxp->platform_cfg_is_bad = true;
>   		return true;
>   	default:
>   		break;
> @@ -339,7 +340,7 @@ int intel_pxp_tee_cmd_create_arb_session(struct intel_pxp *pxp,
>   	if (ret) {
>   		drm_err(&i915->drm, "Failed to send tee msg init arb session, ret=[%d]\n", ret);
>   	} else if (msg_out.header.status != 0) {
> -		if (is_fw_err_platform_config(msg_out.header.status)) {
> +		if (is_fw_err_platform_config(pxp, msg_out.header.status)) {
>   			drm_info_once(&i915->drm,
>   				      "PXP init-arb-session-%d failed due to BIOS/SOC:0x%08x:%s\n",
>   				      arb_session_id, msg_out.header.status,
> @@ -387,7 +388,7 @@ void intel_pxp_tee_end_arb_fw_session(struct intel_pxp *pxp, u32 session_id)
>   		drm_err(&i915->drm, "Failed to send tee msg for inv-stream-key-%u, ret=[%d]\n",
>   			session_id, ret);
>   	} else if (msg_out.header.status != 0) {
> -		if (is_fw_err_platform_config(msg_out.header.status)) {
> +		if (is_fw_err_platform_config(pxp, msg_out.header.status)) {
>   			drm_info_once(&i915->drm,
>   				      "PXP inv-stream-key-%u failed due to BIOS/SOC :0x%08x:%s\n",
>   				      session_id, msg_out.header.status,
> diff --git a/drivers/gpu/drm/i915/pxp/intel_pxp_types.h b/drivers/gpu/drm/i915/pxp/intel_pxp_types.h
> index 1a8765866b8b..7e11fa8034b2 100644
> --- a/drivers/gpu/drm/i915/pxp/intel_pxp_types.h
> +++ b/drivers/gpu/drm/i915/pxp/intel_pxp_types.h
> @@ -26,6 +26,15 @@ struct intel_pxp {
>   	 */
>   	struct intel_gt *ctrl_gt;
>   
> +	/**
> +	 * @platform_cfg_is_bad: used to track if any prior arb session creation resulted
> +	 * in a failure that was caused by a platform configuration issue, meaning that
> +	 * failure will not get resolved without a change to the platform (not kernel)
> +	 * such as BIOS configuration, firwmware update, etc. This bool gets reflected when
> +	 * GET_PARAM:I915_PARAM_PXP_STATUS is called.
> +	 */
> +	bool platform_cfg_is_bad;
> +
>   	/**
>   	 * @kcr_base: base mmio offset for the KCR engine which is different on legacy platforms
>   	 * vs newer platforms where the KCR is inside the media-tile.
>
> base-commit: 6f8963ce33be65c67e53b16fa18325e12ab76861