From: Juston Li Date: Thu, 18 Aug 2022 17:42:05 +0000 (+0000) Subject: drm/i915/pxp: don't start pxp without mei_pxp bind X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=6127b3bcd33299cdebb79ffcc9c9ca135eaf763e;p=linux.git drm/i915/pxp: don't start pxp without mei_pxp bind pxp will not start correctly until after mei_pxp bind completes and intel_pxp_init_hw() is called. Wait for the bind to complete before proceeding with startup. This fixes a race condition during bootup where we observed a small window for pxp commands to be sent, starting pxp before mei_pxp bind completed. Changes since v2: - wait for pxp_component to bind instead of returning -EAGAIN (Daniele) Changes since v1: - check pxp_component instead of pxp_component_added (Daniele) - pxp_component needs tee_mutex (Daniele) - return -EAGAIN so caller knows to retry (Daniele) Signed-off-by: Juston Li Reviewed-by: Andrzej Hajda Signed-off-by: Daniele Ceraolo Spurio Link: https://patchwork.freedesktop.org/patch/msgid/20220818174205.2412730-1-justonli@chromium.org --- diff --git a/drivers/gpu/drm/i915/pxp/intel_pxp.c b/drivers/gpu/drm/i915/pxp/intel_pxp.c index 15311eaed848e..17109c513259a 100644 --- a/drivers/gpu/drm/i915/pxp/intel_pxp.c +++ b/drivers/gpu/drm/i915/pxp/intel_pxp.c @@ -176,6 +176,18 @@ static void pxp_queue_termination(struct intel_pxp *pxp) spin_unlock_irq(>->irq_lock); } +static bool pxp_component_bound(struct intel_pxp *pxp) +{ + bool bound = false; + + mutex_lock(&pxp->tee_mutex); + if (pxp->pxp_component) + bound = true; + mutex_unlock(&pxp->tee_mutex); + + return bound; +} + /* * the arb session is restarted from the irq work when we receive the * termination completion interrupt @@ -187,6 +199,9 @@ int intel_pxp_start(struct intel_pxp *pxp) if (!intel_pxp_is_enabled(pxp)) return -ENODEV; + if (wait_for(pxp_component_bound(pxp), 250)) + return -ENXIO; + mutex_lock(&pxp->arb_mutex); if (pxp->arb_is_valid)