summaryrefslogtreecommitdiffstats
path: root/drivers/bus/mhi/host/pm.c
diff options
context:
space:
mode:
Diffstat (limited to 'drivers/bus/mhi/host/pm.c')
-rw-r--r--drivers/bus/mhi/host/pm.c1283
1 files changed, 1283 insertions, 0 deletions
diff --git a/drivers/bus/mhi/host/pm.c b/drivers/bus/mhi/host/pm.c
new file mode 100644
index 000000000..8a4362d75
--- /dev/null
+++ b/drivers/bus/mhi/host/pm.c
@@ -0,0 +1,1283 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (c) 2018-2020, The Linux Foundation. All rights reserved.
+ *
+ */
+
+#include <linux/delay.h>
+#include <linux/device.h>
+#include <linux/dma-direction.h>
+#include <linux/dma-mapping.h>
+#include <linux/interrupt.h>
+#include <linux/list.h>
+#include <linux/mhi.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/wait.h>
+#include "internal.h"
+
+/*
+ * Not all MHI state transitions are synchronous. Transitions like Linkdown,
+ * SYS_ERR, and shutdown can happen anytime asynchronously. This function will
+ * transition to a new state only if we're allowed to.
+ *
+ * Priority increases as we go down. For instance, from any state in L0, the
+ * transition can be made to states in L1, L2 and L3. A notable exception to
+ * this rule is state DISABLE. From DISABLE state we can only transition to
+ * POR state. Also, while in L2 state, user cannot jump back to previous
+ * L1 or L0 states.
+ *
+ * Valid transitions:
+ * L0: DISABLE <--> POR
+ * POR <--> POR
+ * POR -> M0 -> M2 --> M0
+ * POR -> FW_DL_ERR
+ * FW_DL_ERR <--> FW_DL_ERR
+ * M0 <--> M0
+ * M0 -> FW_DL_ERR
+ * M0 -> M3_ENTER -> M3 -> M3_EXIT --> M0
+ * L1: SYS_ERR_DETECT -> SYS_ERR_PROCESS --> POR
+ * L2: SHUTDOWN_PROCESS -> LD_ERR_FATAL_DETECT
+ * SHUTDOWN_PROCESS -> DISABLE
+ * L3: LD_ERR_FATAL_DETECT <--> LD_ERR_FATAL_DETECT
+ * LD_ERR_FATAL_DETECT -> DISABLE
+ */
+static const struct mhi_pm_transitions dev_state_transitions[] = {
+ /* L0 States */
+ {
+ MHI_PM_DISABLE,
+ MHI_PM_POR
+ },
+ {
+ MHI_PM_POR,
+ MHI_PM_POR | MHI_PM_DISABLE | MHI_PM_M0 |
+ MHI_PM_SYS_ERR_DETECT | MHI_PM_SHUTDOWN_PROCESS |
+ MHI_PM_LD_ERR_FATAL_DETECT | MHI_PM_FW_DL_ERR
+ },
+ {
+ MHI_PM_M0,
+ MHI_PM_M0 | MHI_PM_M2 | MHI_PM_M3_ENTER |
+ MHI_PM_SYS_ERR_DETECT | MHI_PM_SHUTDOWN_PROCESS |
+ MHI_PM_LD_ERR_FATAL_DETECT | MHI_PM_FW_DL_ERR
+ },
+ {
+ MHI_PM_M2,
+ MHI_PM_M0 | MHI_PM_SYS_ERR_DETECT | MHI_PM_SHUTDOWN_PROCESS |
+ MHI_PM_LD_ERR_FATAL_DETECT
+ },
+ {
+ MHI_PM_M3_ENTER,
+ MHI_PM_M3 | MHI_PM_SYS_ERR_DETECT | MHI_PM_SHUTDOWN_PROCESS |
+ MHI_PM_LD_ERR_FATAL_DETECT
+ },
+ {
+ MHI_PM_M3,
+ MHI_PM_M3_EXIT | MHI_PM_SYS_ERR_DETECT |
+ MHI_PM_LD_ERR_FATAL_DETECT
+ },
+ {
+ MHI_PM_M3_EXIT,
+ MHI_PM_M0 | MHI_PM_SYS_ERR_DETECT | MHI_PM_SHUTDOWN_PROCESS |
+ MHI_PM_LD_ERR_FATAL_DETECT
+ },
+ {
+ MHI_PM_FW_DL_ERR,
+ MHI_PM_FW_DL_ERR | MHI_PM_SYS_ERR_DETECT |
+ MHI_PM_SHUTDOWN_PROCESS | MHI_PM_LD_ERR_FATAL_DETECT
+ },
+ /* L1 States */
+ {
+ MHI_PM_SYS_ERR_DETECT,
+ MHI_PM_SYS_ERR_PROCESS | MHI_PM_SHUTDOWN_PROCESS |
+ MHI_PM_LD_ERR_FATAL_DETECT
+ },
+ {
+ MHI_PM_SYS_ERR_PROCESS,
+ MHI_PM_POR | MHI_PM_SHUTDOWN_PROCESS |
+ MHI_PM_LD_ERR_FATAL_DETECT
+ },
+ /* L2 States */
+ {
+ MHI_PM_SHUTDOWN_PROCESS,
+ MHI_PM_DISABLE | MHI_PM_LD_ERR_FATAL_DETECT
+ },
+ /* L3 States */
+ {
+ MHI_PM_LD_ERR_FATAL_DETECT,
+ MHI_PM_LD_ERR_FATAL_DETECT | MHI_PM_DISABLE
+ },
+};
+
+enum mhi_pm_state __must_check mhi_tryset_pm_state(struct mhi_controller *mhi_cntrl,
+ enum mhi_pm_state state)
+{
+ unsigned long cur_state = mhi_cntrl->pm_state;
+ int index = find_last_bit(&cur_state, 32);
+
+ if (unlikely(index >= ARRAY_SIZE(dev_state_transitions)))
+ return cur_state;
+
+ if (unlikely(dev_state_transitions[index].from_state != cur_state))
+ return cur_state;
+
+ if (unlikely(!(dev_state_transitions[index].to_states & state)))
+ return cur_state;
+
+ mhi_cntrl->pm_state = state;
+ return mhi_cntrl->pm_state;
+}
+
+void mhi_set_mhi_state(struct mhi_controller *mhi_cntrl, enum mhi_state state)
+{
+ struct device *dev = &mhi_cntrl->mhi_dev->dev;
+ int ret;
+
+ if (state == MHI_STATE_RESET) {
+ ret = mhi_write_reg_field(mhi_cntrl, mhi_cntrl->regs, MHICTRL,
+ MHICTRL_RESET_MASK, 1);
+ } else {
+ ret = mhi_write_reg_field(mhi_cntrl, mhi_cntrl->regs, MHICTRL,
+ MHICTRL_MHISTATE_MASK, state);
+ }
+
+ if (ret)
+ dev_err(dev, "Failed to set MHI state to: %s\n",
+ mhi_state_str(state));
+}
+
+/* NOP for backward compatibility, host allowed to ring DB in M2 state */
+static void mhi_toggle_dev_wake_nop(struct mhi_controller *mhi_cntrl)
+{
+}
+
+static void mhi_toggle_dev_wake(struct mhi_controller *mhi_cntrl)
+{
+ mhi_cntrl->wake_get(mhi_cntrl, false);
+ mhi_cntrl->wake_put(mhi_cntrl, true);
+}
+
+/* Handle device ready state transition */
+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 interval_us = 25000; /* poll register field every 25 milliseconds */
+ int ret, i;
+
+ /* 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;
+ }
+
+ /* Wait for RESET to be cleared and READY bit to be set by the device */
+ ret = mhi_poll_reg_field(mhi_cntrl, mhi_cntrl->regs, MHICTRL,
+ MHICTRL_RESET_MASK, 0, interval_us);
+ if (ret) {
+ dev_err(dev, "Device failed to clear MHI Reset\n");
+ return ret;
+ }
+
+ ret = mhi_poll_reg_field(mhi_cntrl, mhi_cntrl->regs, MHISTATUS,
+ MHISTATUS_READY_MASK, 1, interval_us);
+ if (ret) {
+ dev_err(dev, "Device failed to enter MHI Ready\n");
+ return ret;
+ }
+
+ dev_dbg(dev, "Device in READY State\n");
+ write_lock_irq(&mhi_cntrl->pm_lock);
+ cur_state = mhi_tryset_pm_state(mhi_cntrl, MHI_PM_POR);
+ mhi_cntrl->dev_state = MHI_STATE_READY;
+ write_unlock_irq(&mhi_cntrl->pm_lock);
+
+ if (cur_state != MHI_PM_POR) {
+ dev_err(dev, "Error moving to state %s from %s\n",
+ to_mhi_pm_state_str(MHI_PM_POR),
+ to_mhi_pm_state_str(cur_state));
+ return -EIO;
+ }
+
+ read_lock_bh(&mhi_cntrl->pm_lock);
+ if (!MHI_REG_ACCESS_VALID(mhi_cntrl->pm_state)) {
+ dev_err(dev, "Device registers not accessible\n");
+ goto error_mmio;
+ }
+
+ /* Configure MMIO registers */
+ ret = mhi_init_mmio(mhi_cntrl);
+ if (ret) {
+ dev_err(dev, "Error configuring MMIO registers\n");
+ goto error_mmio;
+ }
+
+ /* Add elements to all SW event rings */
+ mhi_event = mhi_cntrl->mhi_event;
+ for (i = 0; i < mhi_cntrl->total_ev_rings; i++, mhi_event++) {
+ struct mhi_ring *ring = &mhi_event->ring;
+
+ /* Skip if this is an offload or HW event */
+ if (mhi_event->offload_ev || mhi_event->hw_ring)
+ continue;
+
+ ring->wp = ring->base + ring->len - ring->el_size;
+ *ring->ctxt_wp = cpu_to_le64(ring->iommu_base + ring->len - ring->el_size);
+ /* Update all cores */
+ smp_wmb();
+
+ /* Ring the event ring db */
+ spin_lock_irq(&mhi_event->lock);
+ mhi_ring_er_db(mhi_event);
+ spin_unlock_irq(&mhi_event->lock);
+ }
+
+ /* Set MHI to M0 state */
+ mhi_set_mhi_state(mhi_cntrl, MHI_STATE_M0);
+ read_unlock_bh(&mhi_cntrl->pm_lock);
+
+ return 0;
+
+error_mmio:
+ read_unlock_bh(&mhi_cntrl->pm_lock);
+
+ return -EIO;
+}
+
+int mhi_pm_m0_transition(struct mhi_controller *mhi_cntrl)
+{
+ enum mhi_pm_state cur_state;
+ struct mhi_chan *mhi_chan;
+ struct device *dev = &mhi_cntrl->mhi_dev->dev;
+ int i;
+
+ write_lock_irq(&mhi_cntrl->pm_lock);
+ mhi_cntrl->dev_state = MHI_STATE_M0;
+ cur_state = mhi_tryset_pm_state(mhi_cntrl, MHI_PM_M0);
+ write_unlock_irq(&mhi_cntrl->pm_lock);
+ if (unlikely(cur_state != MHI_PM_M0)) {
+ dev_err(dev, "Unable to transition to M0 state\n");
+ return -EIO;
+ }
+ mhi_cntrl->M0++;
+
+ /* Wake up the device */
+ read_lock_bh(&mhi_cntrl->pm_lock);
+ mhi_cntrl->wake_get(mhi_cntrl, true);
+
+ /* Ring all event rings and CMD ring only if we're in mission mode */
+ if (MHI_IN_MISSION_MODE(mhi_cntrl->ee)) {
+ struct mhi_event *mhi_event = mhi_cntrl->mhi_event;
+ struct mhi_cmd *mhi_cmd =
+ &mhi_cntrl->mhi_cmd[PRIMARY_CMD_RING];
+
+ for (i = 0; i < mhi_cntrl->total_ev_rings; i++, mhi_event++) {
+ if (mhi_event->offload_ev)
+ continue;
+
+ spin_lock_irq(&mhi_event->lock);
+ mhi_ring_er_db(mhi_event);
+ spin_unlock_irq(&mhi_event->lock);
+ }
+
+ /* Only ring primary cmd ring if ring is not empty */
+ spin_lock_irq(&mhi_cmd->lock);
+ if (mhi_cmd->ring.rp != mhi_cmd->ring.wp)
+ mhi_ring_cmd_db(mhi_cntrl, mhi_cmd);
+ spin_unlock_irq(&mhi_cmd->lock);
+ }
+
+ /* Ring channel DB registers */
+ mhi_chan = mhi_cntrl->mhi_chan;
+ for (i = 0; i < mhi_cntrl->max_chan; i++, mhi_chan++) {
+ struct mhi_ring *tre_ring = &mhi_chan->tre_ring;
+
+ if (mhi_chan->db_cfg.reset_req) {
+ write_lock_irq(&mhi_chan->lock);
+ mhi_chan->db_cfg.db_mode = true;
+ write_unlock_irq(&mhi_chan->lock);
+ }
+
+ read_lock_irq(&mhi_chan->lock);
+
+ /* Only ring DB if ring is not empty */
+ if (tre_ring->base && tre_ring->wp != tre_ring->rp &&
+ mhi_chan->ch_state == MHI_CH_STATE_ENABLED)
+ mhi_ring_chan_db(mhi_cntrl, mhi_chan);
+ read_unlock_irq(&mhi_chan->lock);
+ }
+
+ mhi_cntrl->wake_put(mhi_cntrl, false);
+ read_unlock_bh(&mhi_cntrl->pm_lock);
+ wake_up_all(&mhi_cntrl->state_event);
+
+ return 0;
+}
+
+/*
+ * After receiving the MHI state change event from the device indicating the
+ * transition to M1 state, the host can transition the device to M2 state
+ * for keeping it in low power state.
+ */
+void mhi_pm_m1_transition(struct mhi_controller *mhi_cntrl)
+{
+ enum mhi_pm_state state;
+ struct device *dev = &mhi_cntrl->mhi_dev->dev;
+
+ write_lock_irq(&mhi_cntrl->pm_lock);
+ state = mhi_tryset_pm_state(mhi_cntrl, MHI_PM_M2);
+ if (state == MHI_PM_M2) {
+ mhi_set_mhi_state(mhi_cntrl, MHI_STATE_M2);
+ mhi_cntrl->dev_state = MHI_STATE_M2;
+
+ write_unlock_irq(&mhi_cntrl->pm_lock);
+
+ mhi_cntrl->M2++;
+ wake_up_all(&mhi_cntrl->state_event);
+
+ /* If there are any pending resources, exit M2 immediately */
+ if (unlikely(atomic_read(&mhi_cntrl->pending_pkts) ||
+ atomic_read(&mhi_cntrl->dev_wake))) {
+ dev_dbg(dev,
+ "Exiting M2, pending_pkts: %d dev_wake: %d\n",
+ atomic_read(&mhi_cntrl->pending_pkts),
+ atomic_read(&mhi_cntrl->dev_wake));
+ read_lock_bh(&mhi_cntrl->pm_lock);
+ mhi_cntrl->wake_get(mhi_cntrl, true);
+ mhi_cntrl->wake_put(mhi_cntrl, true);
+ read_unlock_bh(&mhi_cntrl->pm_lock);
+ } else {
+ mhi_cntrl->status_cb(mhi_cntrl, MHI_CB_IDLE);
+ }
+ } else {
+ write_unlock_irq(&mhi_cntrl->pm_lock);
+ }
+}
+
+/* MHI M3 completion handler */
+int mhi_pm_m3_transition(struct mhi_controller *mhi_cntrl)
+{
+ enum mhi_pm_state state;
+ struct device *dev = &mhi_cntrl->mhi_dev->dev;
+
+ write_lock_irq(&mhi_cntrl->pm_lock);
+ mhi_cntrl->dev_state = MHI_STATE_M3;
+ state = mhi_tryset_pm_state(mhi_cntrl, MHI_PM_M3);
+ write_unlock_irq(&mhi_cntrl->pm_lock);
+ if (state != MHI_PM_M3) {
+ dev_err(dev, "Unable to transition to M3 state\n");
+ return -EIO;
+ }
+
+ mhi_cntrl->M3++;
+ wake_up_all(&mhi_cntrl->state_event);
+
+ return 0;
+}
+
+/* Handle device Mission Mode transition */
+static int mhi_pm_mission_mode_transition(struct mhi_controller *mhi_cntrl)
+{
+ struct mhi_event *mhi_event;
+ struct device *dev = &mhi_cntrl->mhi_dev->dev;
+ enum mhi_ee_type ee = MHI_EE_MAX, current_ee = mhi_cntrl->ee;
+ int i, ret;
+
+ dev_dbg(dev, "Processing Mission Mode transition\n");
+
+ write_lock_irq(&mhi_cntrl->pm_lock);
+ if (MHI_REG_ACCESS_VALID(mhi_cntrl->pm_state))
+ ee = mhi_get_exec_env(mhi_cntrl);
+
+ if (!MHI_IN_MISSION_MODE(ee)) {
+ mhi_cntrl->pm_state = MHI_PM_LD_ERR_FATAL_DETECT;
+ write_unlock_irq(&mhi_cntrl->pm_lock);
+ wake_up_all(&mhi_cntrl->state_event);
+ return -EIO;
+ }
+ mhi_cntrl->ee = ee;
+ write_unlock_irq(&mhi_cntrl->pm_lock);
+
+ wake_up_all(&mhi_cntrl->state_event);
+
+ device_for_each_child(&mhi_cntrl->mhi_dev->dev, &current_ee,
+ mhi_destroy_device);
+ mhi_cntrl->status_cb(mhi_cntrl, MHI_CB_EE_MISSION_MODE);
+
+ /* Force MHI to be in M0 state before continuing */
+ ret = __mhi_device_get_sync(mhi_cntrl);
+ if (ret)
+ return ret;
+
+ read_lock_bh(&mhi_cntrl->pm_lock);
+
+ if (MHI_PM_IN_ERROR_STATE(mhi_cntrl->pm_state)) {
+ ret = -EIO;
+ goto error_mission_mode;
+ }
+
+ /* Add elements to all HW event rings */
+ mhi_event = mhi_cntrl->mhi_event;
+ for (i = 0; i < mhi_cntrl->total_ev_rings; i++, mhi_event++) {
+ struct mhi_ring *ring = &mhi_event->ring;
+
+ if (mhi_event->offload_ev || !mhi_event->hw_ring)
+ continue;
+
+ ring->wp = ring->base + ring->len - ring->el_size;
+ *ring->ctxt_wp = cpu_to_le64(ring->iommu_base + ring->len - ring->el_size);
+ /* Update to all cores */
+ smp_wmb();
+
+ spin_lock_irq(&mhi_event->lock);
+ if (MHI_DB_ACCESS_VALID(mhi_cntrl))
+ mhi_ring_er_db(mhi_event);
+ spin_unlock_irq(&mhi_event->lock);
+ }
+
+ read_unlock_bh(&mhi_cntrl->pm_lock);
+
+ /*
+ * The MHI devices are only created when the client device switches its
+ * Execution Environment (EE) to either SBL or AMSS states
+ */
+ mhi_create_devices(mhi_cntrl);
+
+ read_lock_bh(&mhi_cntrl->pm_lock);
+
+error_mission_mode:
+ mhi_cntrl->wake_put(mhi_cntrl, false);
+ read_unlock_bh(&mhi_cntrl->pm_lock);
+
+ return ret;
+}
+
+/* Handle shutdown transitions */
+static void mhi_pm_disable_transition(struct mhi_controller *mhi_cntrl)
+{
+ enum mhi_pm_state cur_state;
+ struct mhi_event *mhi_event;
+ struct mhi_cmd_ctxt *cmd_ctxt;
+ struct mhi_cmd *mhi_cmd;
+ struct mhi_event_ctxt *er_ctxt;
+ struct device *dev = &mhi_cntrl->mhi_dev->dev;
+ int ret, i;
+
+ dev_dbg(dev, "Processing disable transition with PM state: %s\n",
+ to_mhi_pm_state_str(mhi_cntrl->pm_state));
+
+ mutex_lock(&mhi_cntrl->pm_mutex);
+
+ /* Trigger MHI RESET so that the device will not access host memory */
+ if (!MHI_PM_IN_FATAL_STATE(mhi_cntrl->pm_state)) {
+ /* Skip MHI RESET if in RDDM state */
+ if (mhi_cntrl->rddm_image && mhi_get_exec_env(mhi_cntrl) == MHI_EE_RDDM)
+ goto skip_mhi_reset;
+
+ dev_dbg(dev, "Triggering MHI Reset in device\n");
+ mhi_set_mhi_state(mhi_cntrl, MHI_STATE_RESET);
+
+ /* Wait for the reset bit to be cleared by the device */
+ ret = mhi_poll_reg_field(mhi_cntrl, mhi_cntrl->regs, MHICTRL,
+ MHICTRL_RESET_MASK, 0, 25000);
+ if (ret)
+ dev_err(dev, "Device failed to clear MHI Reset\n");
+
+ /*
+ * Device will clear BHI_INTVEC as a part of RESET processing,
+ * hence re-program it
+ */
+ mhi_write_reg(mhi_cntrl, mhi_cntrl->bhi, BHI_INTVEC, 0);
+
+ if (!MHI_IN_PBL(mhi_get_exec_env(mhi_cntrl))) {
+ /* wait for ready to be set */
+ ret = mhi_poll_reg_field(mhi_cntrl, mhi_cntrl->regs,
+ MHISTATUS,
+ MHISTATUS_READY_MASK, 1, 25000);
+ if (ret)
+ dev_err(dev, "Device failed to enter READY state\n");
+ }
+ }
+
+skip_mhi_reset:
+ dev_dbg(dev,
+ "Waiting for all pending event ring processing to complete\n");
+ mhi_event = mhi_cntrl->mhi_event;
+ for (i = 0; i < mhi_cntrl->total_ev_rings; i++, mhi_event++) {
+ if (mhi_event->offload_ev)
+ continue;
+ disable_irq(mhi_cntrl->irq[mhi_event->irq]);
+ tasklet_kill(&mhi_event->task);
+ }
+
+ /* Release lock and wait for all pending threads to complete */
+ mutex_unlock(&mhi_cntrl->pm_mutex);
+ dev_dbg(dev, "Waiting for all pending threads to complete\n");
+ wake_up_all(&mhi_cntrl->state_event);
+
+ dev_dbg(dev, "Reset all active channels and remove MHI devices\n");
+ device_for_each_child(&mhi_cntrl->mhi_dev->dev, NULL, mhi_destroy_device);
+
+ mutex_lock(&mhi_cntrl->pm_mutex);
+
+ WARN_ON(atomic_read(&mhi_cntrl->dev_wake));
+ WARN_ON(atomic_read(&mhi_cntrl->pending_pkts));
+
+ /* Reset the ev rings and cmd rings */
+ dev_dbg(dev, "Resetting EV CTXT and CMD CTXT\n");
+ mhi_cmd = mhi_cntrl->mhi_cmd;
+ cmd_ctxt = mhi_cntrl->mhi_ctxt->cmd_ctxt;
+ for (i = 0; i < NR_OF_CMD_RINGS; i++, mhi_cmd++, cmd_ctxt++) {
+ struct mhi_ring *ring = &mhi_cmd->ring;
+
+ ring->rp = ring->base;
+ ring->wp = ring->base;
+ cmd_ctxt->rp = cmd_ctxt->rbase;
+ cmd_ctxt->wp = cmd_ctxt->rbase;
+ }
+
+ mhi_event = mhi_cntrl->mhi_event;
+ er_ctxt = mhi_cntrl->mhi_ctxt->er_ctxt;
+ for (i = 0; i < mhi_cntrl->total_ev_rings; i++, er_ctxt++,
+ mhi_event++) {
+ struct mhi_ring *ring = &mhi_event->ring;
+
+ /* Skip offload events */
+ if (mhi_event->offload_ev)
+ continue;
+
+ ring->rp = ring->base;
+ ring->wp = ring->base;
+ er_ctxt->rp = er_ctxt->rbase;
+ er_ctxt->wp = er_ctxt->rbase;
+ }
+
+ /* Move to disable state */
+ write_lock_irq(&mhi_cntrl->pm_lock);
+ cur_state = mhi_tryset_pm_state(mhi_cntrl, MHI_PM_DISABLE);
+ write_unlock_irq(&mhi_cntrl->pm_lock);
+ if (unlikely(cur_state != MHI_PM_DISABLE))
+ dev_err(dev, "Error moving from PM state: %s to: %s\n",
+ to_mhi_pm_state_str(cur_state),
+ to_mhi_pm_state_str(MHI_PM_DISABLE));
+
+ dev_dbg(dev, "Exiting with PM state: %s, MHI state: %s\n",
+ to_mhi_pm_state_str(mhi_cntrl->pm_state),
+ mhi_state_str(mhi_cntrl->dev_state));
+
+ mutex_unlock(&mhi_cntrl->pm_mutex);
+}
+
+/* Handle system error transitions */
+static void mhi_pm_sys_error_transition(struct mhi_controller *mhi_cntrl)
+{
+ enum mhi_pm_state cur_state, prev_state;
+ enum dev_st_transition next_state;
+ struct mhi_event *mhi_event;
+ struct mhi_cmd_ctxt *cmd_ctxt;
+ struct mhi_cmd *mhi_cmd;
+ struct mhi_event_ctxt *er_ctxt;
+ struct device *dev = &mhi_cntrl->mhi_dev->dev;
+ int ret, i;
+
+ dev_dbg(dev, "Transitioning from PM state: %s to: %s\n",
+ to_mhi_pm_state_str(mhi_cntrl->pm_state),
+ to_mhi_pm_state_str(MHI_PM_SYS_ERR_PROCESS));
+
+ /* We must notify MHI control driver so it can clean up first */
+ mhi_cntrl->status_cb(mhi_cntrl, MHI_CB_SYS_ERROR);
+
+ mutex_lock(&mhi_cntrl->pm_mutex);
+ write_lock_irq(&mhi_cntrl->pm_lock);
+ prev_state = mhi_cntrl->pm_state;
+ cur_state = mhi_tryset_pm_state(mhi_cntrl, MHI_PM_SYS_ERR_PROCESS);
+ write_unlock_irq(&mhi_cntrl->pm_lock);
+
+ if (cur_state != MHI_PM_SYS_ERR_PROCESS) {
+ dev_err(dev, "Failed to transition from PM state: %s to: %s\n",
+ to_mhi_pm_state_str(cur_state),
+ to_mhi_pm_state_str(MHI_PM_SYS_ERR_PROCESS));
+ goto exit_sys_error_transition;
+ }
+
+ mhi_cntrl->ee = MHI_EE_DISABLE_TRANSITION;
+ mhi_cntrl->dev_state = MHI_STATE_RESET;
+
+ /* Wake up threads waiting for state transition */
+ wake_up_all(&mhi_cntrl->state_event);
+
+ /* Trigger MHI RESET so that the device will not access host memory */
+ if (MHI_REG_ACCESS_VALID(prev_state)) {
+ u32 in_reset = -1;
+ unsigned long timeout = msecs_to_jiffies(mhi_cntrl->timeout_ms);
+
+ dev_dbg(dev, "Triggering MHI Reset in device\n");
+ mhi_set_mhi_state(mhi_cntrl, MHI_STATE_RESET);
+
+ /* Wait for the reset bit to be cleared by the device */
+ ret = wait_event_timeout(mhi_cntrl->state_event,
+ mhi_read_reg_field(mhi_cntrl,
+ mhi_cntrl->regs,
+ MHICTRL,
+ MHICTRL_RESET_MASK,
+ &in_reset) ||
+ !in_reset, timeout);
+ if (!ret || in_reset) {
+ dev_err(dev, "Device failed to exit MHI Reset state\n");
+ goto exit_sys_error_transition;
+ }
+
+ /*
+ * Device will clear BHI_INTVEC as a part of RESET processing,
+ * hence re-program it
+ */
+ mhi_write_reg(mhi_cntrl, mhi_cntrl->bhi, BHI_INTVEC, 0);
+ }
+
+ dev_dbg(dev,
+ "Waiting for all pending event ring processing to complete\n");
+ mhi_event = mhi_cntrl->mhi_event;
+ for (i = 0; i < mhi_cntrl->total_ev_rings; i++, mhi_event++) {
+ if (mhi_event->offload_ev)
+ continue;
+ tasklet_kill(&mhi_event->task);
+ }
+
+ /* Release lock and wait for all pending threads to complete */
+ mutex_unlock(&mhi_cntrl->pm_mutex);
+ dev_dbg(dev, "Waiting for all pending threads to complete\n");
+ wake_up_all(&mhi_cntrl->state_event);
+
+ dev_dbg(dev, "Reset all active channels and remove MHI devices\n");
+ device_for_each_child(&mhi_cntrl->mhi_dev->dev, NULL, mhi_destroy_device);
+
+ mutex_lock(&mhi_cntrl->pm_mutex);
+
+ WARN_ON(atomic_read(&mhi_cntrl->dev_wake));
+ WARN_ON(atomic_read(&mhi_cntrl->pending_pkts));
+
+ /* Reset the ev rings and cmd rings */
+ dev_dbg(dev, "Resetting EV CTXT and CMD CTXT\n");
+ mhi_cmd = mhi_cntrl->mhi_cmd;
+ cmd_ctxt = mhi_cntrl->mhi_ctxt->cmd_ctxt;
+ for (i = 0; i < NR_OF_CMD_RINGS; i++, mhi_cmd++, cmd_ctxt++) {
+ struct mhi_ring *ring = &mhi_cmd->ring;
+
+ ring->rp = ring->base;
+ ring->wp = ring->base;
+ cmd_ctxt->rp = cmd_ctxt->rbase;
+ cmd_ctxt->wp = cmd_ctxt->rbase;
+ }
+
+ mhi_event = mhi_cntrl->mhi_event;
+ er_ctxt = mhi_cntrl->mhi_ctxt->er_ctxt;
+ for (i = 0; i < mhi_cntrl->total_ev_rings; i++, er_ctxt++,
+ mhi_event++) {
+ struct mhi_ring *ring = &mhi_event->ring;
+
+ /* Skip offload events */
+ if (mhi_event->offload_ev)
+ continue;
+
+ ring->rp = ring->base;
+ ring->wp = ring->base;
+ er_ctxt->rp = er_ctxt->rbase;
+ er_ctxt->wp = er_ctxt->rbase;
+ }
+
+ /* Transition to next state */
+ if (MHI_IN_PBL(mhi_get_exec_env(mhi_cntrl))) {
+ write_lock_irq(&mhi_cntrl->pm_lock);
+ cur_state = mhi_tryset_pm_state(mhi_cntrl, MHI_PM_POR);
+ write_unlock_irq(&mhi_cntrl->pm_lock);
+ if (cur_state != MHI_PM_POR) {
+ dev_err(dev, "Error moving to state %s from %s\n",
+ to_mhi_pm_state_str(MHI_PM_POR),
+ to_mhi_pm_state_str(cur_state));
+ goto exit_sys_error_transition;
+ }
+ next_state = DEV_ST_TRANSITION_PBL;
+ } else {
+ next_state = DEV_ST_TRANSITION_READY;
+ }
+
+ mhi_queue_state_transition(mhi_cntrl, next_state);
+
+exit_sys_error_transition:
+ dev_dbg(dev, "Exiting with PM state: %s, MHI state: %s\n",
+ to_mhi_pm_state_str(mhi_cntrl->pm_state),
+ mhi_state_str(mhi_cntrl->dev_state));
+
+ mutex_unlock(&mhi_cntrl->pm_mutex);
+}
+
+/* Queue a new work item and schedule work */
+int mhi_queue_state_transition(struct mhi_controller *mhi_cntrl,
+ enum dev_st_transition state)
+{
+ struct state_transition *item = kmalloc(sizeof(*item), GFP_ATOMIC);
+ unsigned long flags;
+
+ if (!item)
+ return -ENOMEM;
+
+ item->state = state;
+ spin_lock_irqsave(&mhi_cntrl->transition_lock, flags);
+ list_add_tail(&item->node, &mhi_cntrl->transition_list);
+ spin_unlock_irqrestore(&mhi_cntrl->transition_lock, flags);
+
+ queue_work(mhi_cntrl->hiprio_wq, &mhi_cntrl->st_worker);
+
+ return 0;
+}
+
+/* SYS_ERR worker */
+void mhi_pm_sys_err_handler(struct mhi_controller *mhi_cntrl)
+{
+ struct device *dev = &mhi_cntrl->mhi_dev->dev;
+
+ /* skip if controller supports RDDM */
+ if (mhi_cntrl->rddm_image) {
+ dev_dbg(dev, "Controller supports RDDM, skip SYS_ERROR\n");
+ return;
+ }
+
+ mhi_queue_state_transition(mhi_cntrl, DEV_ST_TRANSITION_SYS_ERR);
+}
+
+/* Device State Transition worker */
+void mhi_pm_st_worker(struct work_struct *work)
+{
+ struct state_transition *itr, *tmp;
+ LIST_HEAD(head);
+ struct mhi_controller *mhi_cntrl = container_of(work,
+ struct mhi_controller,
+ st_worker);
+ struct device *dev = &mhi_cntrl->mhi_dev->dev;
+
+ spin_lock_irq(&mhi_cntrl->transition_lock);
+ list_splice_tail_init(&mhi_cntrl->transition_list, &head);
+ spin_unlock_irq(&mhi_cntrl->transition_lock);
+
+ list_for_each_entry_safe(itr, tmp, &head, node) {
+ list_del(&itr->node);
+ dev_dbg(dev, "Handling state transition: %s\n",
+ TO_DEV_STATE_TRANS_STR(itr->state));
+
+ switch (itr->state) {
+ case DEV_ST_TRANSITION_PBL:
+ write_lock_irq(&mhi_cntrl->pm_lock);
+ if (MHI_REG_ACCESS_VALID(mhi_cntrl->pm_state))
+ mhi_cntrl->ee = mhi_get_exec_env(mhi_cntrl);
+ write_unlock_irq(&mhi_cntrl->pm_lock);
+ mhi_fw_load_handler(mhi_cntrl);
+ break;
+ case DEV_ST_TRANSITION_SBL:
+ write_lock_irq(&mhi_cntrl->pm_lock);
+ mhi_cntrl->ee = MHI_EE_SBL;
+ write_unlock_irq(&mhi_cntrl->pm_lock);
+ /*
+ * The MHI devices are only created when the client
+ * device switches its Execution Environment (EE) to
+ * either SBL or AMSS states
+ */
+ mhi_create_devices(mhi_cntrl);
+ if (mhi_cntrl->fbc_download)
+ mhi_download_amss_image(mhi_cntrl);
+ break;
+ case DEV_ST_TRANSITION_MISSION_MODE:
+ mhi_pm_mission_mode_transition(mhi_cntrl);
+ break;
+ case DEV_ST_TRANSITION_FP:
+ write_lock_irq(&mhi_cntrl->pm_lock);
+ mhi_cntrl->ee = MHI_EE_FP;
+ write_unlock_irq(&mhi_cntrl->pm_lock);
+ mhi_create_devices(mhi_cntrl);
+ break;
+ case DEV_ST_TRANSITION_READY:
+ mhi_ready_state_transition(mhi_cntrl);
+ break;
+ case DEV_ST_TRANSITION_SYS_ERR:
+ mhi_pm_sys_error_transition(mhi_cntrl);
+ break;
+ case DEV_ST_TRANSITION_DISABLE:
+ mhi_pm_disable_transition(mhi_cntrl);
+ break;
+ default:
+ break;
+ }
+ kfree(itr);
+ }
+}
+
+int mhi_pm_suspend(struct mhi_controller *mhi_cntrl)
+{
+ struct mhi_chan *itr, *tmp;
+ struct device *dev = &mhi_cntrl->mhi_dev->dev;
+ enum mhi_pm_state new_state;
+ int ret;
+
+ if (mhi_cntrl->pm_state == MHI_PM_DISABLE)
+ return -EINVAL;
+
+ if (MHI_PM_IN_ERROR_STATE(mhi_cntrl->pm_state))
+ return -EIO;
+
+ /* Return busy if there are any pending resources */
+ if (atomic_read(&mhi_cntrl->dev_wake) ||
+ atomic_read(&mhi_cntrl->pending_pkts))
+ return -EBUSY;
+
+ /* Take MHI out of M2 state */
+ read_lock_bh(&mhi_cntrl->pm_lock);
+ mhi_cntrl->wake_get(mhi_cntrl, false);
+ read_unlock_bh(&mhi_cntrl->pm_lock);
+
+ ret = wait_event_timeout(mhi_cntrl->state_event,
+ mhi_cntrl->dev_state == MHI_STATE_M0 ||
+ mhi_cntrl->dev_state == MHI_STATE_M1 ||
+ MHI_PM_IN_ERROR_STATE(mhi_cntrl->pm_state),
+ msecs_to_jiffies(mhi_cntrl->timeout_ms));
+
+ read_lock_bh(&mhi_cntrl->pm_lock);
+ mhi_cntrl->wake_put(mhi_cntrl, false);
+ read_unlock_bh(&mhi_cntrl->pm_lock);
+
+ if (!ret || MHI_PM_IN_ERROR_STATE(mhi_cntrl->pm_state)) {
+ dev_err(dev,
+ "Could not enter M0/M1 state");
+ return -EIO;
+ }
+
+ write_lock_irq(&mhi_cntrl->pm_lock);
+
+ if (atomic_read(&mhi_cntrl->dev_wake) ||
+ atomic_read(&mhi_cntrl->pending_pkts)) {
+ write_unlock_irq(&mhi_cntrl->pm_lock);
+ return -EBUSY;
+ }
+
+ dev_dbg(dev, "Allowing M3 transition\n");
+ new_state = mhi_tryset_pm_state(mhi_cntrl, MHI_PM_M3_ENTER);
+ if (new_state != MHI_PM_M3_ENTER) {
+ write_unlock_irq(&mhi_cntrl->pm_lock);
+ dev_err(dev,
+ "Error setting to PM state: %s from: %s\n",
+ to_mhi_pm_state_str(MHI_PM_M3_ENTER),
+ to_mhi_pm_state_str(mhi_cntrl->pm_state));
+ return -EIO;
+ }
+
+ /* Set MHI to M3 and wait for completion */
+ mhi_set_mhi_state(mhi_cntrl, MHI_STATE_M3);
+ write_unlock_irq(&mhi_cntrl->pm_lock);
+ dev_dbg(dev, "Waiting for M3 completion\n");
+
+ ret = wait_event_timeout(mhi_cntrl->state_event,
+ mhi_cntrl->dev_state == MHI_STATE_M3 ||
+ MHI_PM_IN_ERROR_STATE(mhi_cntrl->pm_state),
+ msecs_to_jiffies(mhi_cntrl->timeout_ms));
+
+ if (!ret || MHI_PM_IN_ERROR_STATE(mhi_cntrl->pm_state)) {
+ dev_err(dev,
+ "Did not enter M3 state, MHI state: %s, PM state: %s\n",
+ mhi_state_str(mhi_cntrl->dev_state),
+ to_mhi_pm_state_str(mhi_cntrl->pm_state));
+ return -EIO;
+ }
+
+ /* Notify clients about entering LPM */
+ list_for_each_entry_safe(itr, tmp, &mhi_cntrl->lpm_chans, node) {
+ mutex_lock(&itr->mutex);
+ if (itr->mhi_dev)
+ mhi_notify(itr->mhi_dev, MHI_CB_LPM_ENTER);
+ mutex_unlock(&itr->mutex);
+ }
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(mhi_pm_suspend);
+
+static int __mhi_pm_resume(struct mhi_controller *mhi_cntrl, bool force)
+{
+ struct mhi_chan *itr, *tmp;
+ struct device *dev = &mhi_cntrl->mhi_dev->dev;
+ enum mhi_pm_state cur_state;
+ int ret;
+
+ dev_dbg(dev, "Entered with PM state: %s, MHI state: %s\n",
+ to_mhi_pm_state_str(mhi_cntrl->pm_state),
+ mhi_state_str(mhi_cntrl->dev_state));
+
+ if (mhi_cntrl->pm_state == MHI_PM_DISABLE)
+ return 0;
+
+ if (MHI_PM_IN_ERROR_STATE(mhi_cntrl->pm_state))
+ return -EIO;
+
+ if (mhi_get_mhi_state(mhi_cntrl) != MHI_STATE_M3) {
+ dev_warn(dev, "Resuming from non M3 state (%s)\n",
+ mhi_state_str(mhi_get_mhi_state(mhi_cntrl)));
+ if (!force)
+ return -EINVAL;
+ }
+
+ /* Notify clients about exiting LPM */
+ list_for_each_entry_safe(itr, tmp, &mhi_cntrl->lpm_chans, node) {
+ mutex_lock(&itr->mutex);
+ if (itr->mhi_dev)
+ mhi_notify(itr->mhi_dev, MHI_CB_LPM_EXIT);
+ mutex_unlock(&itr->mutex);
+ }
+
+ write_lock_irq(&mhi_cntrl->pm_lock);
+ cur_state = mhi_tryset_pm_state(mhi_cntrl, MHI_PM_M3_EXIT);
+ if (cur_state != MHI_PM_M3_EXIT) {
+ write_unlock_irq(&mhi_cntrl->pm_lock);
+ dev_info(dev,
+ "Error setting to PM state: %s from: %s\n",
+ to_mhi_pm_state_str(MHI_PM_M3_EXIT),
+ to_mhi_pm_state_str(mhi_cntrl->pm_state));
+ return -EIO;
+ }
+
+ /* Set MHI to M0 and wait for completion */
+ mhi_set_mhi_state(mhi_cntrl, MHI_STATE_M0);
+ write_unlock_irq(&mhi_cntrl->pm_lock);
+
+ ret = wait_event_timeout(mhi_cntrl->state_event,
+ mhi_cntrl->dev_state == MHI_STATE_M0 ||
+ mhi_cntrl->dev_state == MHI_STATE_M2 ||
+ MHI_PM_IN_ERROR_STATE(mhi_cntrl->pm_state),
+ msecs_to_jiffies(mhi_cntrl->timeout_ms));
+
+ if (!ret || MHI_PM_IN_ERROR_STATE(mhi_cntrl->pm_state)) {
+ dev_err(dev,
+ "Did not enter M0 state, MHI state: %s, PM state: %s\n",
+ mhi_state_str(mhi_cntrl->dev_state),
+ to_mhi_pm_state_str(mhi_cntrl->pm_state));
+ return -EIO;
+ }
+
+ return 0;
+}
+
+int mhi_pm_resume(struct mhi_controller *mhi_cntrl)
+{
+ return __mhi_pm_resume(mhi_cntrl, false);
+}
+EXPORT_SYMBOL_GPL(mhi_pm_resume);
+
+int mhi_pm_resume_force(struct mhi_controller *mhi_cntrl)
+{
+ return __mhi_pm_resume(mhi_cntrl, true);
+}
+EXPORT_SYMBOL_GPL(mhi_pm_resume_force);
+
+int __mhi_device_get_sync(struct mhi_controller *mhi_cntrl)
+{
+ int ret;
+
+ /* Wake up the device */
+ read_lock_bh(&mhi_cntrl->pm_lock);
+ if (MHI_PM_IN_ERROR_STATE(mhi_cntrl->pm_state)) {
+ read_unlock_bh(&mhi_cntrl->pm_lock);
+ return -EIO;
+ }
+ mhi_cntrl->wake_get(mhi_cntrl, true);
+ if (MHI_PM_IN_SUSPEND_STATE(mhi_cntrl->pm_state))
+ mhi_trigger_resume(mhi_cntrl);
+ read_unlock_bh(&mhi_cntrl->pm_lock);
+
+ ret = wait_event_timeout(mhi_cntrl->state_event,
+ mhi_cntrl->pm_state == MHI_PM_M0 ||
+ MHI_PM_IN_ERROR_STATE(mhi_cntrl->pm_state),
+ msecs_to_jiffies(mhi_cntrl->timeout_ms));
+
+ if (!ret || MHI_PM_IN_ERROR_STATE(mhi_cntrl->pm_state)) {
+ read_lock_bh(&mhi_cntrl->pm_lock);
+ mhi_cntrl->wake_put(mhi_cntrl, false);
+ read_unlock_bh(&mhi_cntrl->pm_lock);
+ return -EIO;
+ }
+
+ return 0;
+}
+
+/* Assert device wake db */
+static void mhi_assert_dev_wake(struct mhi_controller *mhi_cntrl, bool force)
+{
+ unsigned long flags;
+
+ /*
+ * If force flag is set, then increment the wake count value and
+ * ring wake db
+ */
+ if (unlikely(force)) {
+ spin_lock_irqsave(&mhi_cntrl->wlock, flags);
+ atomic_inc(&mhi_cntrl->dev_wake);
+ if (MHI_WAKE_DB_FORCE_SET_VALID(mhi_cntrl->pm_state) &&
+ !mhi_cntrl->wake_set) {
+ mhi_write_db(mhi_cntrl, mhi_cntrl->wake_db, 1);
+ mhi_cntrl->wake_set = true;
+ }
+ spin_unlock_irqrestore(&mhi_cntrl->wlock, flags);
+ } else {
+ /*
+ * If resources are already requested, then just increment
+ * the wake count value and return
+ */
+ if (likely(atomic_add_unless(&mhi_cntrl->dev_wake, 1, 0)))
+ return;
+
+ spin_lock_irqsave(&mhi_cntrl->wlock, flags);
+ if ((atomic_inc_return(&mhi_cntrl->dev_wake) == 1) &&
+ MHI_WAKE_DB_SET_VALID(mhi_cntrl->pm_state) &&
+ !mhi_cntrl->wake_set) {
+ mhi_write_db(mhi_cntrl, mhi_cntrl->wake_db, 1);
+ mhi_cntrl->wake_set = true;
+ }
+ spin_unlock_irqrestore(&mhi_cntrl->wlock, flags);
+ }
+}
+
+/* De-assert device wake db */
+static void mhi_deassert_dev_wake(struct mhi_controller *mhi_cntrl,
+ bool override)
+{
+ unsigned long flags;
+
+ /*
+ * Only continue if there is a single resource, else just decrement
+ * and return
+ */
+ if (likely(atomic_add_unless(&mhi_cntrl->dev_wake, -1, 1)))
+ return;
+
+ spin_lock_irqsave(&mhi_cntrl->wlock, flags);
+ if ((atomic_dec_return(&mhi_cntrl->dev_wake) == 0) &&
+ MHI_WAKE_DB_CLEAR_VALID(mhi_cntrl->pm_state) && !override &&
+ mhi_cntrl->wake_set) {
+ mhi_write_db(mhi_cntrl, mhi_cntrl->wake_db, 0);
+ mhi_cntrl->wake_set = false;
+ }
+ spin_unlock_irqrestore(&mhi_cntrl->wlock, flags);
+}
+
+int mhi_async_power_up(struct mhi_controller *mhi_cntrl)
+{
+ struct mhi_event *mhi_event = mhi_cntrl->mhi_event;
+ enum mhi_state state;
+ enum mhi_ee_type current_ee;
+ enum dev_st_transition next_state;
+ struct device *dev = &mhi_cntrl->mhi_dev->dev;
+ u32 interval_us = 25000; /* poll register field every 25 milliseconds */
+ int ret, i;
+
+ dev_info(dev, "Requested to power ON\n");
+
+ /* Supply default wake routines if not provided by controller driver */
+ if (!mhi_cntrl->wake_get || !mhi_cntrl->wake_put ||
+ !mhi_cntrl->wake_toggle) {
+ mhi_cntrl->wake_get = mhi_assert_dev_wake;
+ mhi_cntrl->wake_put = mhi_deassert_dev_wake;
+ mhi_cntrl->wake_toggle = (mhi_cntrl->db_access & MHI_PM_M2) ?
+ mhi_toggle_dev_wake_nop : mhi_toggle_dev_wake;
+ }
+
+ mutex_lock(&mhi_cntrl->pm_mutex);
+ mhi_cntrl->pm_state = MHI_PM_DISABLE;
+
+ /* Setup BHI INTVEC */
+ write_lock_irq(&mhi_cntrl->pm_lock);
+ mhi_write_reg(mhi_cntrl, mhi_cntrl->bhi, BHI_INTVEC, 0);
+ mhi_cntrl->pm_state = MHI_PM_POR;
+ mhi_cntrl->ee = MHI_EE_MAX;
+ current_ee = mhi_get_exec_env(mhi_cntrl);
+ write_unlock_irq(&mhi_cntrl->pm_lock);
+
+ /* Confirm that the device is in valid exec env */
+ if (!MHI_POWER_UP_CAPABLE(current_ee)) {
+ dev_err(dev, "%s is not a valid EE for power on\n",
+ TO_MHI_EXEC_STR(current_ee));
+ ret = -EIO;
+ goto error_exit;
+ }
+
+ state = mhi_get_mhi_state(mhi_cntrl);
+ dev_dbg(dev, "Attempting power on with EE: %s, state: %s\n",
+ TO_MHI_EXEC_STR(current_ee), mhi_state_str(state));
+
+ if (state == MHI_STATE_SYS_ERR) {
+ mhi_set_mhi_state(mhi_cntrl, MHI_STATE_RESET);
+ ret = mhi_poll_reg_field(mhi_cntrl, mhi_cntrl->regs, MHICTRL,
+ MHICTRL_RESET_MASK, 0, interval_us);
+ if (ret) {
+ dev_info(dev, "Failed to reset MHI due to syserr state\n");
+ goto error_exit;
+ }
+
+ /*
+ * device cleares INTVEC as part of RESET processing,
+ * re-program it
+ */
+ mhi_write_reg(mhi_cntrl, mhi_cntrl->bhi, BHI_INTVEC, 0);
+ }
+
+ /* IRQs have been requested during probe, so we just need to enable them. */
+ enable_irq(mhi_cntrl->irq[0]);
+
+ for (i = 0; i < mhi_cntrl->total_ev_rings; i++, mhi_event++) {
+ if (mhi_event->offload_ev)
+ continue;
+
+ enable_irq(mhi_cntrl->irq[mhi_event->irq]);
+ }
+
+ /* Transition to next state */
+ next_state = MHI_IN_PBL(current_ee) ?
+ DEV_ST_TRANSITION_PBL : DEV_ST_TRANSITION_READY;
+
+ mhi_queue_state_transition(mhi_cntrl, next_state);
+
+ mutex_unlock(&mhi_cntrl->pm_mutex);
+
+ dev_info(dev, "Power on setup success\n");
+
+ return 0;
+
+error_exit:
+ mhi_cntrl->pm_state = MHI_PM_DISABLE;
+ mutex_unlock(&mhi_cntrl->pm_mutex);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(mhi_async_power_up);
+
+void mhi_power_down(struct mhi_controller *mhi_cntrl, bool graceful)
+{
+ enum mhi_pm_state cur_state, transition_state;
+ struct device *dev = &mhi_cntrl->mhi_dev->dev;
+
+ mutex_lock(&mhi_cntrl->pm_mutex);
+ write_lock_irq(&mhi_cntrl->pm_lock);
+ cur_state = mhi_cntrl->pm_state;
+ if (cur_state == MHI_PM_DISABLE) {
+ write_unlock_irq(&mhi_cntrl->pm_lock);
+ mutex_unlock(&mhi_cntrl->pm_mutex);
+ return; /* Already powered down */
+ }
+
+ /* If it's not a graceful shutdown, force MHI to linkdown state */
+ transition_state = (graceful) ? MHI_PM_SHUTDOWN_PROCESS :
+ MHI_PM_LD_ERR_FATAL_DETECT;
+
+ cur_state = mhi_tryset_pm_state(mhi_cntrl, transition_state);
+ if (cur_state != transition_state) {
+ dev_err(dev, "Failed to move to state: %s from: %s\n",
+ to_mhi_pm_state_str(transition_state),
+ to_mhi_pm_state_str(mhi_cntrl->pm_state));
+ /* Force link down or error fatal detected state */
+ mhi_cntrl->pm_state = MHI_PM_LD_ERR_FATAL_DETECT;
+ }
+
+ /* mark device inactive to avoid any further host processing */
+ mhi_cntrl->ee = MHI_EE_DISABLE_TRANSITION;
+ mhi_cntrl->dev_state = MHI_STATE_RESET;
+
+ wake_up_all(&mhi_cntrl->state_event);
+
+ write_unlock_irq(&mhi_cntrl->pm_lock);
+ mutex_unlock(&mhi_cntrl->pm_mutex);
+
+ mhi_queue_state_transition(mhi_cntrl, DEV_ST_TRANSITION_DISABLE);
+
+ /* Wait for shutdown to complete */
+ flush_work(&mhi_cntrl->st_worker);
+
+ disable_irq(mhi_cntrl->irq[0]);
+}
+EXPORT_SYMBOL_GPL(mhi_power_down);
+
+int mhi_sync_power_up(struct mhi_controller *mhi_cntrl)
+{
+ int ret = mhi_async_power_up(mhi_cntrl);
+
+ if (ret)
+ return ret;
+
+ wait_event_timeout(mhi_cntrl->state_event,
+ MHI_IN_MISSION_MODE(mhi_cntrl->ee) ||
+ MHI_PM_IN_ERROR_STATE(mhi_cntrl->pm_state),
+ msecs_to_jiffies(mhi_cntrl->timeout_ms));
+
+ ret = (MHI_IN_MISSION_MODE(mhi_cntrl->ee)) ? 0 : -ETIMEDOUT;
+ if (ret)
+ mhi_power_down(mhi_cntrl, false);
+
+ return ret;
+}
+EXPORT_SYMBOL(mhi_sync_power_up);
+
+int mhi_force_rddm_mode(struct mhi_controller *mhi_cntrl)
+{
+ struct device *dev = &mhi_cntrl->mhi_dev->dev;
+ int ret;
+
+ /* Check if device is already in RDDM */
+ if (mhi_cntrl->ee == MHI_EE_RDDM)
+ return 0;
+
+ dev_dbg(dev, "Triggering SYS_ERR to force RDDM state\n");
+ mhi_set_mhi_state(mhi_cntrl, MHI_STATE_SYS_ERR);
+
+ /* Wait for RDDM event */
+ ret = wait_event_timeout(mhi_cntrl->state_event,
+ mhi_cntrl->ee == MHI_EE_RDDM,
+ msecs_to_jiffies(mhi_cntrl->timeout_ms));
+ ret = ret ? 0 : -EIO;
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(mhi_force_rddm_mode);
+
+void mhi_device_get(struct mhi_device *mhi_dev)
+{
+ struct mhi_controller *mhi_cntrl = mhi_dev->mhi_cntrl;
+
+ mhi_dev->dev_wake++;
+ read_lock_bh(&mhi_cntrl->pm_lock);
+ if (MHI_PM_IN_SUSPEND_STATE(mhi_cntrl->pm_state))
+ mhi_trigger_resume(mhi_cntrl);
+
+ mhi_cntrl->wake_get(mhi_cntrl, true);
+ read_unlock_bh(&mhi_cntrl->pm_lock);
+}
+EXPORT_SYMBOL_GPL(mhi_device_get);
+
+int mhi_device_get_sync(struct mhi_device *mhi_dev)
+{
+ struct mhi_controller *mhi_cntrl = mhi_dev->mhi_cntrl;
+ int ret;
+
+ ret = __mhi_device_get_sync(mhi_cntrl);
+ if (!ret)
+ mhi_dev->dev_wake++;
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(mhi_device_get_sync);
+
+void mhi_device_put(struct mhi_device *mhi_dev)
+{
+ struct mhi_controller *mhi_cntrl = mhi_dev->mhi_cntrl;
+
+ mhi_dev->dev_wake--;
+ read_lock_bh(&mhi_cntrl->pm_lock);
+ if (MHI_PM_IN_SUSPEND_STATE(mhi_cntrl->pm_state))
+ mhi_trigger_resume(mhi_cntrl);
+
+ mhi_cntrl->wake_put(mhi_cntrl, false);
+ read_unlock_bh(&mhi_cntrl->pm_lock);
+}
+EXPORT_SYMBOL_GPL(mhi_device_put);
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-23 19:28:14 +0000