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path: root/drivers/bus/mhi/core/pm.c
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Diffstat (limited to 'drivers/bus/mhi/core/pm.c')
-rw-r--r--drivers/bus/mhi/core/pm.c685
1 files changed, 685 insertions, 0 deletions
diff --git a/drivers/bus/mhi/core/pm.c b/drivers/bus/mhi/core/pm.c
new file mode 100644
index 000000000000..785dfd8d0b25
--- /dev/null
+++ b/drivers/bus/mhi/core/pm.c
@@ -0,0 +1,685 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (c) 2018-2020, The Linux Foundation. All rights reserved.
+ *
+ */
+
+#define dev_fmt(fmt) "MHI: " fmt
+
+#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 -> DISABLE
+ * L3: LD_ERR_FATAL_DETECT <--> LD_ERR_FATAL_DETECT
+ * LD_ERR_FATAL_DETECT -> SHUTDOWN_PROCESS
+ */
+static struct mhi_pm_transitions const 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_SHUTDOWN_PROCESS | 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_SHUTDOWN_PROCESS
+ },
+};
+
+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)
+{
+ if (state == MHI_STATE_RESET) {
+ mhi_write_reg_field(mhi_cntrl, mhi_cntrl->regs, MHICTRL,
+ MHICTRL_RESET_MASK, MHICTRL_RESET_SHIFT, 1);
+ } else {
+ mhi_write_reg_field(mhi_cntrl, mhi_cntrl->regs, MHICTRL,
+ MHICTRL_MHISTATE_MASK,
+ MHICTRL_MHISTATE_SHIFT, state);
+ }
+}
+
+/* Handle device ready state transition */
+int mhi_ready_state_transition(struct mhi_controller *mhi_cntrl)
+{
+ void __iomem *base = mhi_cntrl->regs;
+ u32 reset = 1, ready = 0;
+ struct mhi_event *mhi_event;
+ enum mhi_pm_state cur_state;
+ 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(mhi_cntrl->dev, "Device link is not accessible\n");
+ return -EIO;
+ }
+
+ /* Timeout if device did not transition to ready state */
+ if (reset || !ready) {
+ dev_err(mhi_cntrl->dev, "Device Ready timeout\n");
+ return -ETIMEDOUT;
+ }
+
+ dev_dbg(mhi_cntrl->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(mhi_cntrl->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(mhi_cntrl->dev, "Device registers not accessible\n");
+ goto error_mmio;
+ }
+
+ /* Configure MMIO registers */
+ ret = mhi_init_mmio(mhi_cntrl);
+ if (ret) {
+ dev_err(mhi_cntrl->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 = 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;
+ 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(mhi_cntrl->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;
+
+ write_lock_irq(&mhi_chan->lock);
+ if (mhi_chan->db_cfg.reset_req)
+ mhi_chan->db_cfg.db_mode = true;
+
+ /* Only ring DB if ring is not empty */
+ if (tre_ring->base && tre_ring->wp != tre_ring->rp)
+ mhi_ring_chan_db(mhi_cntrl, mhi_chan);
+ write_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;
+
+ 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;
+ mhi_cntrl->M2++;
+
+ write_unlock_irq(&mhi_cntrl->pm_lock);
+ 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(mhi_cntrl->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_cntrl->priv_data,
+ 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;
+
+ 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(mhi_cntrl->dev, "Unable to transition to M3 state\n");
+ return -EIO;
+ }
+
+ wake_up_all(&mhi_cntrl->state_event);
+ mhi_cntrl->M3++;
+
+ return 0;
+}
+
+/* Handle device Mission Mode transition */
+static int mhi_pm_mission_mode_transition(struct mhi_controller *mhi_cntrl)
+{
+ int i, ret;
+ struct mhi_event *mhi_event;
+
+ dev_dbg(mhi_cntrl->dev, "Processing Mission Mode transition\n");
+
+ 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);
+
+ if (!MHI_IN_MISSION_MODE(mhi_cntrl->ee))
+ return -EIO;
+
+ wake_up_all(&mhi_cntrl->state_event);
+
+ mhi_cntrl->status_cb(mhi_cntrl, mhi_cntrl->priv_data,
+ 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 = 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 SYS_ERR and Shutdown transitions */
+static void mhi_pm_disable_transition(struct mhi_controller *mhi_cntrl,
+ enum mhi_pm_state transition_state)
+{
+ enum mhi_pm_state cur_state, prev_state;
+ struct mhi_event *mhi_event;
+ struct mhi_cmd_ctxt *cmd_ctxt;
+ struct mhi_cmd *mhi_cmd;
+ struct mhi_event_ctxt *er_ctxt;
+ int ret, i;
+
+ dev_dbg(mhi_cntrl->dev,
+ "Transitioning from PM state: %s to: %s\n",
+ to_mhi_pm_state_str(mhi_cntrl->pm_state),
+ to_mhi_pm_state_str(transition_state));
+
+ /* We must notify MHI control driver so it can clean up first */
+ if (transition_state == MHI_PM_SYS_ERR_PROCESS) {
+ mhi_cntrl->status_cb(mhi_cntrl, mhi_cntrl->priv_data,
+ 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, transition_state);
+ if (cur_state == transition_state) {
+ mhi_cntrl->ee = MHI_EE_DISABLE_TRANSITION;
+ mhi_cntrl->dev_state = MHI_STATE_RESET;
+ }
+ write_unlock_irq(&mhi_cntrl->pm_lock);
+
+ /* Wake up threads waiting for state transition */
+ wake_up_all(&mhi_cntrl->state_event);
+
+ if (cur_state != transition_state) {
+ dev_err(mhi_cntrl->dev,
+ "Failed to transition to state: %s from: %s\n",
+ to_mhi_pm_state_str(transition_state),
+ to_mhi_pm_state_str(cur_state));
+ mutex_unlock(&mhi_cntrl->pm_mutex);
+ return;
+ }
+
+ /* 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(mhi_cntrl->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,
+ MHICTRL_RESET_SHIFT,
+ &in_reset) ||
+ !in_reset, timeout);
+ if ((!ret || in_reset) && cur_state == MHI_PM_SYS_ERR_PROCESS) {
+ dev_err(mhi_cntrl->dev,
+ "Device failed to exit MHI Reset state\n");
+ mutex_unlock(&mhi_cntrl->pm_mutex);
+ return;
+ }
+
+ /*
+ * 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(mhi_cntrl->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(mhi_cntrl->dev,
+ "Waiting for all pending threads to complete\n");
+ wake_up_all(&mhi_cntrl->state_event);
+ flush_work(&mhi_cntrl->st_worker);
+ flush_work(&mhi_cntrl->fw_worker);
+
+ dev_dbg(mhi_cntrl->dev,
+ "Reset all active channels and remove MHI devices\n");
+ device_for_each_child(mhi_cntrl->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(mhi_cntrl->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;
+ }
+
+ if (cur_state == MHI_PM_SYS_ERR_PROCESS) {
+ mhi_ready_state_transition(mhi_cntrl);
+ } else {
+ /* 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(mhi_cntrl->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(mhi_cntrl->dev, "Exiting with PM state: %s, MHI state: %s\n",
+ to_mhi_pm_state_str(mhi_cntrl->pm_state),
+ TO_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);
+
+ schedule_work(&mhi_cntrl->st_worker);
+
+ return 0;
+}
+
+/* SYS_ERR worker */
+void mhi_pm_sys_err_worker(struct work_struct *work)
+{
+ struct mhi_controller *mhi_cntrl = container_of(work,
+ struct mhi_controller,
+ syserr_worker);
+
+ mhi_pm_disable_transition(mhi_cntrl, MHI_PM_SYS_ERR_PROCESS);
+}
+
+/* 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);
+ 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_info(mhi_cntrl->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);
+ if (MHI_IN_PBL(mhi_cntrl->ee))
+ wake_up_all(&mhi_cntrl->state_event);
+ 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);
+ break;
+ case DEV_ST_TRANSITION_MISSION_MODE:
+ mhi_pm_mission_mode_transition(mhi_cntrl);
+ break;
+ case DEV_ST_TRANSITION_READY:
+ mhi_ready_state_transition(mhi_cntrl);
+ break;
+ default:
+ break;
+ }
+ kfree(itr);
+ }
+}
+
+int __mhi_device_get_sync(struct mhi_controller *mhi_cntrl)
+{
+ int ret;
+
+ /* Wake up the device */
+ read_lock_bh(&mhi_cntrl->pm_lock);
+ mhi_cntrl->wake_get(mhi_cntrl, true);
+ if (MHI_PM_IN_SUSPEND_STATE(mhi_cntrl->pm_state)) {
+ pm_wakeup_event(&mhi_cntrl->mhi_dev->dev, 0);
+ mhi_cntrl->runtime_get(mhi_cntrl, mhi_cntrl->priv_data);
+ mhi_cntrl->runtime_put(mhi_cntrl, mhi_cntrl->priv_data);
+ }
+ 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;
+}
generated by cgit v1.2.3 (git 2.25.1) at 2024-05-30 12:25:01 +0000