drm/i915/pxp: add device link between i915 and mei_pxp

Add device link with i915 as consumer and mei_pxp as supplier
to ensure proper ordering of power flows.

V2: condition on absence of heci_pxp to filter out DG

Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: Alan Previn <alan.previn.teres.alexis@intel.com>
Reviewed-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20230125082637.118970-3-alan.previn.teres.alexis@intel.com

diff --git a/drivers/gpu/drm/i915/pxp/intel_pxp_tee.c b/drivers/gpu/drm/i915/pxp/intel_pxp_tee.c
index 73aa8015f828fceed298c5966c9eb036c52574b2..b5bc0b87a1d02f8a4bbf8fbb8983f0bd2857fb11 100644 (file)
--- a/drivers/gpu/drm/i915/pxp/intel_pxp_tee.c
+++ b/drivers/gpu/drm/i915/pxp/intel_pxp_tee.c
@@ -127,6 +127,12 @@ static int i915_pxp_tee_component_bind(struct device *i915_kdev,
        intel_wakeref_t wakeref;
        int ret = 0;
 
+       if (!HAS_HECI_PXP(i915)) {
+               pxp->dev_link = device_link_add(i915_kdev, tee_kdev, DL_FLAG_STATELESS);
+               if (drm_WARN_ON(&i915->drm, !pxp->dev_link))
+                       return -ENODEV;
+       }
+
        mutex_lock(&pxp->tee_mutex);
        pxp->pxp_component = data;
        pxp->pxp_component->tee_dev = tee_kdev;
@@ -169,6 +175,11 @@ static void i915_pxp_tee_component_unbind(struct device *i915_kdev,
        mutex_lock(&pxp->tee_mutex);
        pxp->pxp_component = NULL;
        mutex_unlock(&pxp->tee_mutex);
+
+       if (pxp->dev_link) {
+               device_link_del(pxp->dev_link);
+               pxp->dev_link = NULL;
+       }
 }
 
 static const struct component_ops i915_pxp_tee_component_ops = {

diff --git a/drivers/gpu/drm/i915/pxp/intel_pxp_types.h b/drivers/gpu/drm/i915/pxp/intel_pxp_types.h
index 7dc5f08d1583f62b28def9ba40d91e1bd7ec809c..007de49e1ea4297cf75524d09ed41f4627c44828 100644 (file)
--- a/drivers/gpu/drm/i915/pxp/intel_pxp_types.h
+++ b/drivers/gpu/drm/i915/pxp/intel_pxp_types.h
@@ -32,6 +32,9 @@ struct intel_pxp {
         * which are protected by &tee_mutex.
         */
        struct i915_pxp_component *pxp_component;
+
+       /* @dev_link: Enforce module relationship for power management ordering. */
+       struct device_link *dev_link;
        /**
         * @pxp_component_added: track if the pxp component has been added.
         * Set and cleared in tee init and fini functions respectively.