/**
* mei_txe_aliveness_wait - waits for aliveness to settle
*
* @dev: the device structure
* @expected: expected aliveness value
*
* Waits for HICR_HOST_ALIVENESS_RESP.ALIVENESS_RESP to be set
* returns returns 0 on success and < 0 otherwise
*/
static int mei_txe_aliveness_wait(struct mei_device *dev, u32 expected)
{
struct mei_txe_hw *hw = to_txe_hw(dev);
const unsigned long timeout =
msecs_to_jiffies(SEC_ALIVENESS_WAIT_TIMEOUT);
long err;
int ret;
hw->aliveness = mei_txe_aliveness_get(dev);
if (hw->aliveness == expected)
return 0;
mutex_unlock(&dev->device_lock);
err = wait_event_timeout(hw->wait_aliveness_resp,
dev->pg_event == MEI_PG_EVENT_RECEIVED, timeout);
mutex_lock(&dev->device_lock);
hw->aliveness = mei_txe_aliveness_get(dev);
ret = hw->aliveness == expected ? 0 : -ETIME;
if (ret)
dev_warn(&dev->pdev->dev, "aliveness timed out = %ld aliveness = %d event = %d\n",
err, hw->aliveness, dev->pg_event);
else
dev_dbg(&dev->pdev->dev, "aliveness settled after = %d msec aliveness = %d event = %d\n",
jiffies_to_msecs(timeout - err),
hw->aliveness, dev->pg_event);
dev->pg_event = MEI_PG_EVENT_IDLE;
return ret;
}
/**
* mei_txe_hw_config - configure hardware at the start of the devices
*
* @dev: the device structure
*
* Configure hardware at the start of the device should be done only
* once at the device probe time
*/
static void mei_txe_hw_config(struct mei_device *dev)
{
struct mei_txe_hw *hw = to_txe_hw(dev);
/* Doesn't change in runtime */
dev->hbuf_depth = PAYLOAD_SIZE / 4;
hw->aliveness = mei_txe_aliveness_get(dev);
hw->readiness = mei_txe_readiness_get(dev);
dev_dbg(&dev->pdev->dev, "aliveness_resp = 0x%08x, readiness = 0x%08x.\n",
hw->aliveness, hw->readiness);
}
/**
* mei_txe_check_and_ack_intrs - translate multi BAR interrupt into
* single bit mask and acknowledge the interrupts
*
* @dev: the device structure
* @do_ack: acknowledge interrupts
*
* Return: true if found interrupts to process.
*/
static bool mei_txe_check_and_ack_intrs(struct mei_device *dev, bool do_ack)
{
struct mei_txe_hw *hw = to_txe_hw(dev);
u32 hisr;
u32 hhisr;
u32 ipc_isr;
u32 aliveness;
bool generated;
/* read interrupt registers */
hhisr = mei_txe_br_reg_read(hw, HHISR_REG);
generated = (hhisr & IPC_HHIER_MSK);
if (!generated)
goto out;
hisr = mei_txe_br_reg_read(hw, HISR_REG);
aliveness = mei_txe_aliveness_get(dev);
if (hhisr & IPC_HHIER_SEC && aliveness) {
ipc_isr = mei_txe_sec_reg_read_silent(hw,
SEC_IPC_HOST_INT_STATUS_REG);
} else {
ipc_isr = 0;
hhisr &= ~IPC_HHIER_SEC;
}
generated = generated ||
(hisr & HISR_INT_STS_MSK) ||
(ipc_isr & SEC_IPC_HOST_INT_STATUS_PENDING);
if (generated && do_ack) {
/* Save the interrupt causes */
hw->intr_cause |= hisr & HISR_INT_STS_MSK;
if (ipc_isr & SEC_IPC_HOST_INT_STATUS_IN_RDY)
hw->intr_cause |= TXE_INTR_IN_READY;
mei_txe_intr_disable(dev);
/* Clear the interrupts in hierarchy:
* IPC and Bridge, than the High Level */
mei_txe_sec_reg_write_silent(hw,
SEC_IPC_HOST_INT_STATUS_REG, ipc_isr);
mei_txe_br_reg_write(hw, HISR_REG, hisr);
mei_txe_br_reg_write(hw, HHISR_REG, hhisr);
}
out:
return generated;
}
/**
* mei_txe_hw_reset - resets host and fw.
*
* @dev: the device structure
* @intr_enable: if interrupt should be enabled after reset.
*
* returns 0 on success and < 0 in case of error
*/
static int mei_txe_hw_reset(struct mei_device *dev, bool intr_enable)
{
struct mei_txe_hw *hw = to_txe_hw(dev);
u32 aliveness_req;
/*
* read input doorbell to ensure consistency between Bridge and SeC
* return value might be garbage return
*/
(void)mei_txe_sec_reg_read_silent(hw, SEC_IPC_INPUT_DOORBELL_REG);
aliveness_req = mei_txe_aliveness_req_get(dev);
hw->aliveness = mei_txe_aliveness_get(dev);
/* Disable interrupts in this stage we will poll */
mei_txe_intr_disable(dev);
/*
* If Aliveness Request and Aliveness Response are not equal then
* wait for them to be equal
* Since we might have interrupts disabled - poll for it
*/
if (aliveness_req != hw->aliveness)
if (mei_txe_aliveness_poll(dev, aliveness_req) < 0) {
dev_err(&dev->pdev->dev,
"wait for aliveness settle failed ... bailing out\n");
return -EIO;
}
/*
* If Aliveness Request and Aliveness Response are set then clear them
*/
if (aliveness_req) {
mei_txe_aliveness_set(dev, 0);
if (mei_txe_aliveness_poll(dev, 0) < 0) {
dev_err(&dev->pdev->dev,
"wait for aliveness failed ... bailing out\n");
return -EIO;
}
}
/*
* Set rediness RDY_CLR bit
*/
mei_txe_readiness_clear(dev);
return 0;
}
/**
* mei_txe_aliveness_poll - waits for aliveness to settle
*
* @dev: the device structure
* @expected: expected aliveness value
*
* Polls for HICR_HOST_ALIVENESS_RESP.ALIVENESS_RESP to be set
*
* Return: 0 if the expected value was received, -ETIME otherwise
*/
static int mei_txe_aliveness_poll(struct mei_device *dev, u32 expected)
{
struct mei_txe_hw *hw = to_txe_hw(dev);
ktime_t stop, start;
start = ktime_get();
stop = ktime_add(start, ms_to_ktime(SEC_ALIVENESS_WAIT_TIMEOUT));
do {
hw->aliveness = mei_txe_aliveness_get(dev);
if (hw->aliveness == expected) {
dev->pg_event = MEI_PG_EVENT_IDLE;
dev_dbg(dev->dev, "aliveness settled after %lld usecs\n",
ktime_to_us(ktime_sub(ktime_get(), start)));
return 0;
}
usleep_range(20, 50);
} while (ktime_before(ktime_get(), stop));
dev->pg_event = MEI_PG_EVENT_IDLE;
dev_err(dev->dev, "aliveness timed out\n");
return -ETIME;
}
/**
* mei_txe_aliveness_poll - waits for aliveness to settle
*
* @dev: the device structure
* @expected: expected aliveness value
*
* Polls for HICR_HOST_ALIVENESS_RESP.ALIVENESS_RESP to be set
* returns > 0 if the expected value was received, -ETIME otherwise
*/
static int mei_txe_aliveness_poll(struct mei_device *dev, u32 expected)
{
struct mei_txe_hw *hw = to_txe_hw(dev);
int t = 0;
do {
hw->aliveness = mei_txe_aliveness_get(dev);
if (hw->aliveness == expected) {
dev->pg_event = MEI_PG_EVENT_IDLE;
dev_dbg(&dev->pdev->dev,
"aliveness settled after %d msecs\n", t);
return t;
}
mutex_unlock(&dev->device_lock);
msleep(MSEC_PER_SEC / 5);
mutex_lock(&dev->device_lock);
t += MSEC_PER_SEC / 5;
} while (t < SEC_ALIVENESS_WAIT_TIMEOUT);
dev->pg_event = MEI_PG_EVENT_IDLE;
dev_err(&dev->pdev->dev, "aliveness timed out\n");
return -ETIME;
}
/**
* mei_txe_irq_thread_handler - txe interrupt thread
*
* @irq: The irq number
* @dev_id: pointer to the device structure
*
* returns irqreturn_t
*
*/
irqreturn_t mei_txe_irq_thread_handler(int irq, void *dev_id)
{
struct mei_device *dev = (struct mei_device *) dev_id;
struct mei_txe_hw *hw = to_txe_hw(dev);
struct mei_cl_cb complete_list;
s32 slots;
int rets = 0;
dev_dbg(&dev->pdev->dev, "irq thread: Interrupt Registers HHISR|HISR|SEC=%02X|%04X|%02X\n",
mei_txe_br_reg_read(hw, HHISR_REG),
mei_txe_br_reg_read(hw, HISR_REG),
mei_txe_sec_reg_read_silent(hw, SEC_IPC_HOST_INT_STATUS_REG));
/* initialize our complete list */
mutex_lock(&dev->device_lock);
mei_io_list_init(&complete_list);
if (pci_dev_msi_enabled(dev->pdev))
mei_txe_check_and_ack_intrs(dev, true);
/* show irq events */
mei_txe_pending_interrupts(dev);
hw->aliveness = mei_txe_aliveness_get(dev);
hw->readiness = mei_txe_readiness_get(dev);
/* Readiness:
* Detection of TXE driver going through reset
* or TXE driver resetting the HECI interface.
*/
if (test_and_clear_bit(TXE_INTR_READINESS_BIT, &hw->intr_cause)) {
dev_dbg(&dev->pdev->dev, "Readiness Interrupt was received...\n");
/* Check if SeC is going through reset */
if (mei_txe_readiness_is_sec_rdy(hw->readiness)) {
dev_dbg(&dev->pdev->dev, "we need to start the dev.\n");
dev->recvd_hw_ready = true;
} else {
dev->recvd_hw_ready = false;
if (dev->dev_state != MEI_DEV_RESETTING) {
dev_warn(&dev->pdev->dev, "FW not ready: resetting.\n");
schedule_work(&dev->reset_work);
goto end;
}
}
wake_up(&dev->wait_hw_ready);
}
/************************************************************/
/* Check interrupt cause:
* Aliveness: Detection of SeC acknowledge of host request that
* it remain alive or host cancellation of that request.
*/
if (test_and_clear_bit(TXE_INTR_ALIVENESS_BIT, &hw->intr_cause)) {
/* Clear the interrupt cause */
dev_dbg(&dev->pdev->dev,
"Aliveness Interrupt: Status: %d\n", hw->aliveness);
dev->pg_event = MEI_PG_EVENT_RECEIVED;
if (waitqueue_active(&hw->wait_aliveness_resp))
wake_up(&hw->wait_aliveness_resp);
}
/* Output Doorbell:
* Detection of SeC having sent output to host
*/
slots = mei_count_full_read_slots(dev);
if (test_and_clear_bit(TXE_INTR_OUT_DB_BIT, &hw->intr_cause)) {
/* Read from TXE */
rets = mei_irq_read_handler(dev, &complete_list, &slots);
if (rets && dev->dev_state != MEI_DEV_RESETTING) {
dev_err(&dev->pdev->dev,
"mei_irq_read_handler ret = %d.\n", rets);
schedule_work(&dev->reset_work);
goto end;
}
}
/* Input Ready: Detection if host can write to SeC */
if (test_and_clear_bit(TXE_INTR_IN_READY_BIT, &hw->intr_cause)) {
dev->hbuf_is_ready = true;
hw->slots = dev->hbuf_depth;
}
if (hw->aliveness && dev->hbuf_is_ready) {
/* get the real register value */
dev->hbuf_is_ready = mei_hbuf_is_ready(dev);
rets = mei_irq_write_handler(dev, &complete_list);
if (rets && rets != -EMSGSIZE)
dev_err(&dev->pdev->dev, "mei_irq_write_handler ret = %d.\n",
rets);
dev->hbuf_is_ready = mei_hbuf_is_ready(dev);
}
mei_irq_compl_handler(dev, &complete_list);
end:
dev_dbg(&dev->pdev->dev, "interrupt thread end ret = %d\n", rets);
mutex_unlock(&dev->device_lock);
mei_enable_interrupts(dev);
return IRQ_HANDLED;
}