+++ /dev/null
-/*
- * AR6K Driver layer event handling (i.e. interrupts, message polling)
- *
- * Copyright (c) 2007 Atheros Communications Inc.
- * All rights reserved.
- *
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License version 2 as
- * published by the Free Software Foundation;
- *
- * Software distributed under the License is distributed on an "AS
- * IS" basis, WITHOUT WARRANTY OF ANY KIND, either express or
- * implied. See the License for the specific language governing
- * rights and limitations under the License.
- *
- *
- *
- */
-#include "a_config.h"
-#include "athdefs.h"
-#include "a_types.h"
-#include "AR6Khwreg.h"
-#include "a_osapi.h"
-#include "a_debug.h"
-#include "hif.h"
-#include "htc_packet.h"
-#include "ar6k.h"
-
-extern void AR6KFreeIOPacket(AR6K_DEVICE *pDev, HTC_PACKET *pPacket);
-extern HTC_PACKET *AR6KAllocIOPacket(AR6K_DEVICE *pDev);
-
-static A_STATUS DevServiceDebugInterrupt(AR6K_DEVICE *pDev);
-
-#define DELAY_PER_INTERVAL_MS 10 /* 10 MS delay per polling interval */
-
-/* completion routine for ALL HIF layer async I/O */
-A_STATUS DevRWCompletionHandler(void *context, A_STATUS status)
-{
- HTC_PACKET *pPacket = (HTC_PACKET *)context;
-
- COMPLETE_HTC_PACKET(pPacket,status);
-
- return A_OK;
-}
-
-/* mailbox recv message polling */
-A_STATUS DevPollMboxMsgRecv(AR6K_DEVICE *pDev,
- A_UINT32 *pLookAhead,
- int TimeoutMS)
-{
- A_STATUS status = A_OK;
- int timeout = TimeoutMS/DELAY_PER_INTERVAL_MS;
-
- AR_DEBUG_ASSERT(timeout > 0);
-
- AR_DEBUG_PRINTF(ATH_DEBUG_RECV,("+DevPollMboxMsgRecv \n"));
-
- while (TRUE) {
-
- if (pDev->GetPendingEventsFunc != NULL)
- {
-
- HIF_PENDING_EVENTS_INFO events;
-
- /* the HIF layer uses a special mechanism to get events, do this
- * synchronously */
- status = pDev->GetPendingEventsFunc(pDev->HIFDevice,
- &events,
- NULL);
- if (A_FAILED(status))
- {
- AR_DEBUG_PRINTF(ATH_DEBUG_ERR,("Failed to get pending events \n"));
- break;
- }
-
- if (events.Events & HIF_RECV_MSG_AVAIL)
- {
- /* there is a message available, the lookahead should be valid now */
- *pLookAhead = events.LookAhead;
-
- break;
- }
- }
- else
- {
-
- /* this is the standard HIF way.... */
- /* load the register table */
- status = HIFReadWrite(pDev->HIFDevice,
- HOST_INT_STATUS_ADDRESS,
- (A_UINT8 *)&pDev->IrqProcRegisters,
- AR6K_IRQ_PROC_REGS_SIZE,
- HIF_RD_SYNC_BYTE_INC,
- NULL);
-
- if (A_FAILED(status))
- {
- AR_DEBUG_PRINTF(ATH_DEBUG_ERR,("Failed to read register table \n"));
- break;
- }
-
- /* check for MBOX data and valid lookahead */
- if (pDev->IrqProcRegisters.host_int_status & (1 << HTC_MAILBOX))
- {
- if (pDev->IrqProcRegisters.rx_lookahead_valid & (1 << HTC_MAILBOX))
- {
- /* mailbox has a message and the look ahead is valid */
- *pLookAhead = pDev->IrqProcRegisters.rx_lookahead[HTC_MAILBOX];
- break;
- }
- }
-
- }
-
- timeout--;
-
- if (timeout <= 0)
- {
- AR_DEBUG_PRINTF(ATH_DEBUG_ERR, (" Timeout waiting for recv message \n"));
- status = A_ERROR;
-
- /* check if the target asserted */
- if ( pDev->IrqProcRegisters.counter_int_status & AR6K_TARGET_DEBUG_INTR_MASK) {
- /* target signaled an assert, process this pending interrupt
- * this will call the target failure handler */
- DevServiceDebugInterrupt(pDev);
- }
-
- break;
- }
-
- /* delay a little */
- msleep(DELAY_PER_INTERVAL_MS);
- AR_DEBUG_PRINTF(ATH_DEBUG_RECV,(" Retry Mbox Poll : %d \n",timeout));
- }
-
- AR_DEBUG_PRINTF(ATH_DEBUG_RECV,("-DevPollMboxMsgRecv \n"));
-
- return status;
-}
-
-static A_STATUS DevServiceCPUInterrupt(AR6K_DEVICE *pDev)
-{
- A_STATUS status;
- A_UINT8 cpu_int_status;
- A_UINT8 regBuffer[4];
-
- AR_DEBUG_PRINTF(ATH_DEBUG_IRQ, ("CPU Interrupt\n"));
- cpu_int_status = pDev->IrqProcRegisters.cpu_int_status &
- pDev->IrqEnableRegisters.cpu_int_status_enable;
- AR_DEBUG_ASSERT(cpu_int_status);
- AR_DEBUG_PRINTF(ATH_DEBUG_IRQ,
- ("Valid interrupt source(s) in CPU_INT_STATUS: 0x%x\n",
- cpu_int_status));
-
- /* Clear the interrupt */
- pDev->IrqProcRegisters.cpu_int_status &= ~cpu_int_status; /* W1C */
-
- /* set up the register transfer buffer to hit the register 4 times , this is done
- * to make the access 4-byte aligned to mitigate issues with host bus interconnects that
- * restrict bus transfer lengths to be a multiple of 4-bytes */
-
- /* set W1C value to clear the interrupt, this hits the register first */
- regBuffer[0] = cpu_int_status;
- /* the remaining 4 values are set to zero which have no-effect */
- regBuffer[1] = 0;
- regBuffer[2] = 0;
- regBuffer[3] = 0;
-
- status = HIFReadWrite(pDev->HIFDevice,
- CPU_INT_STATUS_ADDRESS,
- regBuffer,
- 4,
- HIF_WR_SYNC_BYTE_FIX,
- NULL);
-
- AR_DEBUG_ASSERT(status == A_OK);
- return status;
-}
-
-
-static A_STATUS DevServiceErrorInterrupt(AR6K_DEVICE *pDev)
-{
- A_STATUS status;
- A_UINT8 error_int_status;
- A_UINT8 regBuffer[4];
-
- AR_DEBUG_PRINTF(ATH_DEBUG_IRQ, ("Error Interrupt\n"));
- error_int_status = pDev->IrqProcRegisters.error_int_status & 0x0F;
- AR_DEBUG_ASSERT(error_int_status);
- AR_DEBUG_PRINTF(ATH_DEBUG_IRQ,
- ("Valid interrupt source(s) in ERROR_INT_STATUS: 0x%x\n",
- error_int_status));
-
- if (ERROR_INT_STATUS_WAKEUP_GET(error_int_status)) {
- /* Wakeup */
- AR_DEBUG_PRINTF(ATH_DEBUG_IRQ, ("Error : Wakeup\n"));
- }
-
- if (ERROR_INT_STATUS_RX_UNDERFLOW_GET(error_int_status)) {
- /* Rx Underflow */
- AR_DEBUG_PRINTF(ATH_DEBUG_ERR, ("Error : Rx Underflow\n"));
- }
-
- if (ERROR_INT_STATUS_TX_OVERFLOW_GET(error_int_status)) {
- /* Tx Overflow */
- AR_DEBUG_PRINTF(ATH_DEBUG_ERR, ("Error : Tx Overflow\n"));
- }
-
- /* Clear the interrupt */
- pDev->IrqProcRegisters.error_int_status &= ~error_int_status; /* W1C */
-
- /* set up the register transfer buffer to hit the register 4 times , this is done
- * to make the access 4-byte aligned to mitigate issues with host bus interconnects that
- * restrict bus transfer lengths to be a multiple of 4-bytes */
-
- /* set W1C value to clear the interrupt, this hits the register first */
- regBuffer[0] = error_int_status;
- /* the remaining 4 values are set to zero which have no-effect */
- regBuffer[1] = 0;
- regBuffer[2] = 0;
- regBuffer[3] = 0;
-
- status = HIFReadWrite(pDev->HIFDevice,
- ERROR_INT_STATUS_ADDRESS,
- regBuffer,
- 4,
- HIF_WR_SYNC_BYTE_FIX,
- NULL);
-
- AR_DEBUG_ASSERT(status == A_OK);
- return status;
-}
-
-static A_STATUS DevServiceDebugInterrupt(AR6K_DEVICE *pDev)
-{
- A_UINT32 dummy;
- A_STATUS status;
-
- /* Send a target failure event to the application */
- AR_DEBUG_PRINTF(ATH_DEBUG_ERR, ("Target debug interrupt\n"));
-
- if (pDev->TargetFailureCallback != NULL) {
- pDev->TargetFailureCallback(pDev->HTCContext);
- }
-
- /* clear the interrupt , the debug error interrupt is
- * counter 0 */
- /* read counter to clear interrupt */
- status = HIFReadWrite(pDev->HIFDevice,
- COUNT_DEC_ADDRESS,
- (A_UINT8 *)&dummy,
- 4,
- HIF_RD_SYNC_BYTE_INC,
- NULL);
-
- AR_DEBUG_ASSERT(status == A_OK);
- return status;
-}
-
-static A_STATUS DevServiceCounterInterrupt(AR6K_DEVICE *pDev)
-{
- A_UINT8 counter_int_status;
-
- AR_DEBUG_PRINTF(ATH_DEBUG_IRQ, ("Counter Interrupt\n"));
-
- counter_int_status = pDev->IrqProcRegisters.counter_int_status &
- pDev->IrqEnableRegisters.counter_int_status_enable;
-
- AR_DEBUG_ASSERT(counter_int_status);
- AR_DEBUG_PRINTF(ATH_DEBUG_IRQ,
- ("Valid interrupt source(s) in COUNTER_INT_STATUS: 0x%x\n",
- counter_int_status));
-
- /* Check if the debug interrupt is pending */
- if (counter_int_status & AR6K_TARGET_DEBUG_INTR_MASK) {
- return DevServiceDebugInterrupt(pDev);
- }
-
- return A_OK;
-}
-
-/* callback when our fetch to get interrupt status registers completes */
-static void DevGetEventAsyncHandler(void *Context, HTC_PACKET *pPacket)
-{
- AR6K_DEVICE *pDev = (AR6K_DEVICE *)Context;
- A_UINT32 lookAhead = 0;
- A_BOOL otherInts = FALSE;
-
- AR_DEBUG_PRINTF(ATH_DEBUG_IRQ,("+DevGetEventAsyncHandler: (dev: 0x%X)\n", (A_UINT32)pDev));
-
- do {
-
- if (A_FAILED(pPacket->Status)) {
- AR_DEBUG_PRINTF(ATH_DEBUG_ERR,
- (" GetEvents I/O request failed, status:%d \n", pPacket->Status));
- /* bail out, don't unmask HIF interrupt */
- break;
- }
-
- if (pDev->GetPendingEventsFunc != NULL) {
- /* the HIF layer collected the information for us */
- HIF_PENDING_EVENTS_INFO *pEvents = (HIF_PENDING_EVENTS_INFO *)pPacket->pBuffer;
- if (pEvents->Events & HIF_RECV_MSG_AVAIL) {
- lookAhead = pEvents->LookAhead;
- if (0 == lookAhead) {
- AR_DEBUG_PRINTF(ATH_DEBUG_ERR,(" DevGetEventAsyncHandler1, lookAhead is zero! \n"));
- }
- }
- if (pEvents->Events & HIF_OTHER_EVENTS) {
- otherInts = TRUE;
- }
- } else {
- /* standard interrupt table handling.... */
- AR6K_IRQ_PROC_REGISTERS *pReg = (AR6K_IRQ_PROC_REGISTERS *)pPacket->pBuffer;
- A_UINT8 host_int_status;
-
- host_int_status = pReg->host_int_status & pDev->IrqEnableRegisters.int_status_enable;
-
- if (host_int_status & (1 << HTC_MAILBOX)) {
- host_int_status &= ~(1 << HTC_MAILBOX);
- if (pReg->rx_lookahead_valid & (1 << HTC_MAILBOX)) {
- /* mailbox has a message and the look ahead is valid */
- lookAhead = pReg->rx_lookahead[HTC_MAILBOX];
- if (0 == lookAhead) {
- AR_DEBUG_PRINTF(ATH_DEBUG_ERR,(" DevGetEventAsyncHandler2, lookAhead is zero! \n"));
- }
- }
- }
-
- if (host_int_status) {
- /* there are other interrupts to handle */
- otherInts = TRUE;
- }
- }
-
- if (otherInts || (lookAhead == 0)) {
- /* if there are other interrupts to process, we cannot do this in the async handler so
- * ack the interrupt which will cause our sync handler to run again
- * if however there are no more messages, we can now ack the interrupt */
- AR_DEBUG_PRINTF(ATH_DEBUG_IRQ,
- (" Acking interrupt from DevGetEventAsyncHandler (otherints:%d, lookahead:0x%X)\n",
- otherInts, lookAhead));
- HIFAckInterrupt(pDev->HIFDevice);
- } else {
- AR_DEBUG_PRINTF(ATH_DEBUG_IRQ,
- (" DevGetEventAsyncHandler : detected another message, lookahead :0x%X \n",
- lookAhead));
- /* lookahead is non-zero and there are no other interrupts to service,
- * go get the next message */
- pDev->MessagePendingCallback(pDev->HTCContext, lookAhead, NULL);
- }
-
- } while (FALSE);
-
- /* free this IO packet */
- AR6KFreeIOPacket(pDev,pPacket);
- AR_DEBUG_PRINTF(ATH_DEBUG_IRQ,("-DevGetEventAsyncHandler \n"));
-}
-
-/* called by the HTC layer when it wants us to check if the device has any more pending
- * recv messages, this starts off a series of async requests to read interrupt registers */
-A_STATUS DevCheckPendingRecvMsgsAsync(void *context)
-{
- AR6K_DEVICE *pDev = (AR6K_DEVICE *)context;
- A_STATUS status = A_OK;
- HTC_PACKET *pIOPacket;
-
- /* this is called in an ASYNC only context, we may NOT block, sleep or call any apis that can
- * cause us to switch contexts */
-
- AR_DEBUG_PRINTF(ATH_DEBUG_IRQ,("+DevCheckPendingRecvMsgsAsync: (dev: 0x%X)\n", (A_UINT32)pDev));
-
- do {
-
- if (HIF_DEVICE_IRQ_SYNC_ONLY == pDev->HifIRQProcessingMode) {
- /* break the async processing chain right here, no need to continue.
- * The DevDsrHandler() will handle things in a loop when things are driven
- * synchronously */
- break;
- }
- /* first allocate one of our HTC packets we created for async I/O
- * we reuse HTC packet definitions so that we can use the completion mechanism
- * in DevRWCompletionHandler() */
- pIOPacket = AR6KAllocIOPacket(pDev);
-
- if (NULL == pIOPacket) {
- /* there should be only 1 asynchronous request out at a time to read these registers
- * so this should actually never happen */
- status = A_NO_MEMORY;
- AR_DEBUG_ASSERT(FALSE);
- break;
- }
-
- /* stick in our completion routine when the I/O operation completes */
- pIOPacket->Completion = DevGetEventAsyncHandler;
- pIOPacket->pContext = pDev;
-
- if (pDev->GetPendingEventsFunc) {
- /* HIF layer has it's own mechanism, pass the IO to it.. */
- status = pDev->GetPendingEventsFunc(pDev->HIFDevice,
- (HIF_PENDING_EVENTS_INFO *)pIOPacket->pBuffer,
- pIOPacket);
-
- } else {
- /* standard way, read the interrupt register table asynchronously again */
- status = HIFReadWrite(pDev->HIFDevice,
- HOST_INT_STATUS_ADDRESS,
- pIOPacket->pBuffer,
- AR6K_IRQ_PROC_REGS_SIZE,
- HIF_RD_ASYNC_BYTE_INC,
- pIOPacket);
- }
-
- AR_DEBUG_PRINTF(ATH_DEBUG_IRQ,(" Async IO issued to get interrupt status...\n"));
- } while (FALSE);
-
- AR_DEBUG_PRINTF(ATH_DEBUG_IRQ,("-DevCheckPendingRecvMsgsAsync \n"));
-
- return status;
-}
-
-/* process pending interrupts synchronously */
-static A_STATUS ProcessPendingIRQs(AR6K_DEVICE *pDev, A_BOOL *pDone, A_BOOL *pASyncProcessing)
-{
- A_STATUS status = A_OK;
- A_UINT8 host_int_status = 0;
- A_UINT32 lookAhead = 0;
-
- AR_DEBUG_PRINTF(ATH_DEBUG_IRQ,("+ProcessPendingIRQs: (dev: 0x%X)\n", (A_UINT32)pDev));
-
- /*** NOTE: the HIF implementation guarantees that the context of this call allows
- * us to perform SYNCHRONOUS I/O, that is we can block, sleep or call any API that
- * can block or switch thread/task ontexts.
- * This is a fully schedulable context.
- * */
- do {
-
- if (pDev->GetPendingEventsFunc != NULL) {
- HIF_PENDING_EVENTS_INFO events;
-
- /* the HIF layer uses a special mechanism to get events
- * get this synchronously */
- status = pDev->GetPendingEventsFunc(pDev->HIFDevice,
- &events,
- NULL);
-
- if (A_FAILED(status)) {
- break;
- }
-
- if (events.Events & HIF_RECV_MSG_AVAIL) {
- lookAhead = events.LookAhead;
- if (0 == lookAhead) {
- AR_DEBUG_PRINTF(ATH_DEBUG_ERR,(" ProcessPendingIRQs1 lookAhead is zero! \n"));
- }
- }
-
- if (!(events.Events & HIF_OTHER_EVENTS) ||
- !(pDev->IrqEnableRegisters.int_status_enable & OTHER_INTS_ENABLED)) {
- /* no need to read the register table, no other interesting interrupts.
- * Some interfaces (like SPI) can shadow interrupt sources without
- * requiring the host to do a full table read */
- break;
- }
-
- /* otherwise fall through and read the register table */
- }
-
- /*
- * Read the first 28 bytes of the HTC register table. This will yield us
- * the value of different int status registers and the lookahead
- * registers.
- * length = sizeof(int_status) + sizeof(cpu_int_status) +
- * sizeof(error_int_status) + sizeof(counter_int_status) +
- * sizeof(mbox_frame) + sizeof(rx_lookahead_valid) +
- * sizeof(hole) + sizeof(rx_lookahead) +
- * sizeof(int_status_enable) + sizeof(cpu_int_status_enable) +
- * sizeof(error_status_enable) +
- * sizeof(counter_int_status_enable);
- *
- */
- status = HIFReadWrite(pDev->HIFDevice,
- HOST_INT_STATUS_ADDRESS,
- (A_UINT8 *)&pDev->IrqProcRegisters,
- AR6K_IRQ_PROC_REGS_SIZE,
- HIF_RD_SYNC_BYTE_INC,
- NULL);
-
- if (A_FAILED(status)) {
- break;
- }
-
- if (AR_DEBUG_LVL_CHECK(ATH_DEBUG_IRQ)) {
- DevDumpRegisters(&pDev->IrqProcRegisters,
- &pDev->IrqEnableRegisters);
- }
-
- /* Update only those registers that are enabled */
- host_int_status = pDev->IrqProcRegisters.host_int_status &
- pDev->IrqEnableRegisters.int_status_enable;
-
- if (NULL == pDev->GetPendingEventsFunc) {
- /* only look at mailbox status if the HIF layer did not provide this function,
- * on some HIF interfaces reading the RX lookahead is not valid to do */
- if (host_int_status & (1 << HTC_MAILBOX)) {
- /* mask out pending mailbox value, we use "lookAhead" as the real flag for
- * mailbox processing below */
- host_int_status &= ~(1 << HTC_MAILBOX);
- if (pDev->IrqProcRegisters.rx_lookahead_valid & (1 << HTC_MAILBOX)) {
- /* mailbox has a message and the look ahead is valid */
- lookAhead = pDev->IrqProcRegisters.rx_lookahead[HTC_MAILBOX];
- if (0 == lookAhead) {
- AR_DEBUG_PRINTF(ATH_DEBUG_ERR,(" ProcessPendingIRQs2, lookAhead is zero! \n"));
- }
- }
- }
- } else {
- /* not valid to check if the HIF has another mechanism for reading mailbox pending status*/
- host_int_status &= ~(1 << HTC_MAILBOX);
- }
-
- } while (FALSE);
-
-
- do {
-
- /* did the interrupt status fetches succeed? */
- if (A_FAILED(status)) {
- break;
- }
-
- if ((0 == host_int_status) && (0 == lookAhead)) {
- /* nothing to process, the caller can use this to break out of a loop */
- *pDone = TRUE;
- break;
- }
-
- if (lookAhead != 0) {
- AR_DEBUG_PRINTF(ATH_DEBUG_IRQ,("Pending mailbox message, LookAhead: 0x%X\n",lookAhead));
- /* Mailbox Interrupt, the HTC layer may issue async requests to empty the
- * mailbox...
- * When emptying the recv mailbox we use the async handler above called from the
- * completion routine of the callers read request. This can improve performance
- * by reducing context switching when we rapidly pull packets */
- status = pDev->MessagePendingCallback(pDev->HTCContext, lookAhead, pASyncProcessing);
- if (A_FAILED(status)) {
- break;
- }
- }
-
- /* now handle the rest of them */
- AR_DEBUG_PRINTF(ATH_DEBUG_IRQ,
- (" Valid interrupt source(s) for OTHER interrupts: 0x%x\n",
- host_int_status));
-
- if (HOST_INT_STATUS_CPU_GET(host_int_status)) {
- /* CPU Interrupt */
- status = DevServiceCPUInterrupt(pDev);
- if (A_FAILED(status)){
- break;
- }
- }
-
- if (HOST_INT_STATUS_ERROR_GET(host_int_status)) {
- /* Error Interrupt */
- status = DevServiceErrorInterrupt(pDev);
- if (A_FAILED(status)){
- break;
- }
- }
-
- if (HOST_INT_STATUS_COUNTER_GET(host_int_status)) {
- /* Counter Interrupt */
- status = DevServiceCounterInterrupt(pDev);
- if (A_FAILED(status)){
- break;
- }
- }
-
- } while (FALSE);
-
- AR_DEBUG_PRINTF(ATH_DEBUG_IRQ,("-ProcessPendingIRQs: (done:%d, async:%d) status=%d \n",
- *pDone, *pASyncProcessing, status));
-
- return status;
-}
-
-
-/* Synchronousinterrupt handler, this handler kicks off all interrupt processing.*/
-A_STATUS DevDsrHandler(void *context)
-{
- AR6K_DEVICE *pDev = (AR6K_DEVICE *)context;
- A_STATUS status = A_OK;
- A_BOOL done = FALSE;
- A_BOOL asyncProc = FALSE;
-
- AR_DEBUG_PRINTF(ATH_DEBUG_IRQ,("+DevDsrHandler: (dev: 0x%X)\n", (A_UINT32)pDev));
-
-
- while (!done) {
- status = ProcessPendingIRQs(pDev, &done, &asyncProc);
- if (A_FAILED(status)) {
- break;
- }
-
- if (HIF_DEVICE_IRQ_SYNC_ONLY == pDev->HifIRQProcessingMode) {
- /* the HIF layer does not allow async IRQ processing, override the asyncProc flag */
- asyncProc = FALSE;
- /* this will cause us to re-enter ProcessPendingIRQ() and re-read interrupt status registers.
- * this has a nice side effect of blocking us until all async read requests are completed.
- * This behavior is required on some HIF implementations that do not allow ASYNC
- * processing in interrupt handlers (like Windows CE) */
- }
-
- if (asyncProc) {
- /* the function performed some async I/O for performance, we
- need to exit the ISR immediately, the check below will prevent the interrupt from being
- Ack'd while we handle it asynchronously */
- break;
- }
-
- }
-
- if (A_SUCCESS(status) && !asyncProc) {
- /* Ack the interrupt only if :
- * 1. we did not get any errors in processing interrupts
- * 2. there are no outstanding async processing requests */
- AR_DEBUG_PRINTF(ATH_DEBUG_IRQ,(" Acking interrupt from DevDsrHandler \n"));
- HIFAckInterrupt(pDev->HIFDevice);
- }
-
- AR_DEBUG_PRINTF(ATH_DEBUG_IRQ,("-DevDsrHandler \n"));
- return A_OK;
-}
-
-
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