From c6546b58fd8a2f2ad7788d44fefccd4fb95f2fad Mon Sep 17 00:00:00 2001 From: Bhaumik Bhatt Date: Wed, 10 Feb 2021 18:17:18 -0800 Subject: bus: mhi: core: Move to polling method to wait for MHI ready In certain devices, it is likely that there is no incoming MHI interrupt for a transition to MHI READY state. One such example is the move from Pass Through to an SBL or AMSS execution environment. In order to facilitate faster bootup times as there is no need to wait until timeout_ms completes, MHI host can poll every 25 milliseconds to check if device has entered MHI READY until a maximum timeout of twice the timeout_ms is reached. Signed-off-by: Bhaumik Bhatt --- drivers/bus/mhi/core/pm.c | 32 ++++++++++++++++---------------- 1 file changed, 16 insertions(+), 16 deletions(-) diff --git a/drivers/bus/mhi/core/pm.c b/drivers/bus/mhi/core/pm.c index 681960c72d2a..625bf581ce2f 100644 --- a/drivers/bus/mhi/core/pm.c +++ b/drivers/bus/mhi/core/pm.c @@ -9,6 +9,7 @@ #include #include #include +#include #include #include #include @@ -157,30 +158,29 @@ int mhi_ready_state_transition(struct mhi_controller *mhi_cntrl) struct mhi_event *mhi_event; enum mhi_pm_state cur_state; struct device *dev = &mhi_cntrl->mhi_dev->dev; - u32 reset = 1, ready = 0; + u32 reset, ready; int ret, i; - /* Wait for RESET to be cleared and READY bit to be set by the device */ - wait_event_timeout(mhi_cntrl->state_event, - MHI_PM_IN_FATAL_STATE(mhi_cntrl->pm_state) || - mhi_read_reg_field(mhi_cntrl, base, MHICTRL, - MHICTRL_RESET_MASK, - MHICTRL_RESET_SHIFT, &reset) || - mhi_read_reg_field(mhi_cntrl, base, MHISTATUS, - MHISTATUS_READY_MASK, - MHISTATUS_READY_SHIFT, &ready) || - (!reset && ready), - msecs_to_jiffies(mhi_cntrl->timeout_ms)); - /* Check if device entered error state */ if (MHI_PM_IN_FATAL_STATE(mhi_cntrl->pm_state)) { dev_err(dev, "Device link is not accessible\n"); return -EIO; } - /* Timeout if device did not transition to ready state */ - if (reset || !ready) { - dev_err(dev, "Device Ready timeout\n"); + /* Wait for RESET to be cleared and READY bit to be set by the device */ + ret = readl_relaxed_poll_timeout(base + MHICTRL, reset, + !(reset & MHICTRL_RESET_MASK), 25000, + mhi_cntrl->timeout_ms * 1000); + if (ret) { + dev_err(dev, "Device failed to clear MHI Reset\n"); + return -ETIMEDOUT; + } + + ret = readl_relaxed_poll_timeout(base + MHISTATUS, ready, + (ready & MHISTATUS_READY_MASK), 25000, + mhi_cntrl->timeout_ms * 1000); + if (ret) { + dev_err(dev, "Device failed to enter MHI Ready\n"); return -ETIMEDOUT; } -- cgit v1.2.3