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-rw-r--r--drivers/ar6000/miscdrv/common_drv.c467
-rw-r--r--drivers/ar6000/miscdrv/credit_dist.c346
2 files changed, 813 insertions, 0 deletions
diff --git a/drivers/ar6000/miscdrv/common_drv.c b/drivers/ar6000/miscdrv/common_drv.c
new file mode 100644
index 00000000000..4f127346665
--- /dev/null
+++ b/drivers/ar6000/miscdrv/common_drv.c
@@ -0,0 +1,467 @@
+
+/*
+ *
+ * Copyright (c) 2004-2007 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 "targaddrs.h"
+#include "a_osapi.h"
+#include "hif.h"
+#include "htc_api.h"
+#include "bmi.h"
+#include "bmi_msg.h"
+#include "common_drv.h"
+#include "a_debug.h"
+#include "targaddrs.h"
+
+#define HOST_INTEREST_ITEM_ADDRESS(target, item) \
+(((TargetType) == TARGET_TYPE_AR6001) ? \
+ AR6001_HOST_INTEREST_ITEM_ADDRESS(item) : \
+ AR6002_HOST_INTEREST_ITEM_ADDRESS(item))
+
+
+/* Compile the 4BYTE version of the window register setup routine,
+ * This mitigates host interconnect issues with non-4byte aligned bus requests, some
+ * interconnects use bus adapters that impose strict limitations.
+ * Since diag window access is not intended for performance critical operations, the 4byte mode should
+ * be satisfactory even though it generates 4X the bus activity. */
+
+#ifdef USE_4BYTE_REGISTER_ACCESS
+
+ /* set the window address register (using 4-byte register access ). */
+A_STATUS ar6000_SetAddressWindowRegister(HIF_DEVICE *hifDevice, A_UINT32 RegisterAddr, A_UINT32 Address)
+{
+ A_STATUS status;
+ A_UINT8 addrValue[4];
+ int i;
+
+ /* write bytes 1,2,3 of the register to set the upper address bytes, the LSB is written
+ * last to initiate the access cycle */
+
+ for (i = 1; i <= 3; i++) {
+ /* fill the buffer with the address byte value we want to hit 4 times*/
+ addrValue[0] = ((A_UINT8 *)&Address)[i];
+ addrValue[1] = addrValue[0];
+ addrValue[2] = addrValue[0];
+ addrValue[3] = addrValue[0];
+
+ /* hit each byte of the register address with a 4-byte write operation to the same address,
+ * this is a harmless operation */
+ status = HIFReadWrite(hifDevice,
+ RegisterAddr+i,
+ addrValue,
+ 4,
+ HIF_WR_SYNC_BYTE_FIX,
+ NULL);
+ if (status != A_OK) {
+ break;
+ }
+ }
+
+ if (status != A_OK) {
+ AR_DEBUG_PRINTF(ATH_LOG_ERR, ("Cannot write initial bytes of 0x%x to window reg: 0x%X \n",
+ RegisterAddr, Address));
+ return status;
+ }
+
+ /* write the address register again, this time write the whole 4-byte value.
+ * The effect here is that the LSB write causes the cycle to start, the extra
+ * 3 byte write to bytes 1,2,3 has no effect since we are writing the same values again */
+ status = HIFReadWrite(hifDevice,
+ RegisterAddr,
+ (A_UCHAR *)(&Address),
+ 4,
+ HIF_WR_SYNC_BYTE_INC,
+ NULL);
+
+ if (status != A_OK) {
+ AR_DEBUG_PRINTF(ATH_LOG_ERR, ("Cannot write 0x%x to window reg: 0x%X \n",
+ RegisterAddr, Address));
+ return status;
+ }
+
+ return A_OK;
+
+
+
+}
+
+
+#else
+
+ /* set the window address register */
+A_STATUS ar6000_SetAddressWindowRegister(HIF_DEVICE *hifDevice, A_UINT32 RegisterAddr, A_UINT32 Address)
+{
+ A_STATUS status;
+
+ /* write bytes 1,2,3 of the register to set the upper address bytes, the LSB is written
+ * last to initiate the access cycle */
+ status = HIFReadWrite(hifDevice,
+ RegisterAddr+1, /* write upper 3 bytes */
+ ((A_UCHAR *)(&Address))+1,
+ sizeof(A_UINT32)-1,
+ HIF_WR_SYNC_BYTE_INC,
+ NULL);
+
+ if (status != A_OK) {
+ AR_DEBUG_PRINTF(ATH_LOG_ERR, ("Cannot write initial bytes of 0x%x to window reg: 0x%X \n",
+ RegisterAddr, Address));
+ return status;
+ }
+
+ /* write the LSB of the register, this initiates the operation */
+ status = HIFReadWrite(hifDevice,
+ RegisterAddr,
+ (A_UCHAR *)(&Address),
+ sizeof(A_UINT8),
+ HIF_WR_SYNC_BYTE_INC,
+ NULL);
+
+ if (status != A_OK) {
+ AR_DEBUG_PRINTF(ATH_LOG_ERR, ("Cannot write 0x%x to window reg: 0x%X \n",
+ RegisterAddr, Address));
+ return status;
+ }
+
+ return A_OK;
+}
+
+#endif
+
+/*
+ * Read from the AR6000 through its diagnostic window.
+ * No cooperation from the Target is required for this.
+ */
+A_STATUS
+ar6000_ReadRegDiag(HIF_DEVICE *hifDevice, A_UINT32 *address, A_UINT32 *data)
+{
+ A_STATUS status;
+
+ /* set window register to start read cycle */
+ status = ar6000_SetAddressWindowRegister(hifDevice,
+ WINDOW_READ_ADDR_ADDRESS,
+ *address);
+
+ if (status != A_OK) {
+ return status;
+ }
+
+ /* read the data */
+ status = HIFReadWrite(hifDevice,
+ WINDOW_DATA_ADDRESS,
+ (A_UCHAR *)data,
+ sizeof(A_UINT32),
+ HIF_RD_SYNC_BYTE_INC,
+ NULL);
+ if (status != A_OK) {
+ AR_DEBUG_PRINTF(ATH_LOG_ERR, ("Cannot read from WINDOW_DATA_ADDRESS\n"));
+ return status;
+ }
+
+ return status;
+}
+
+
+/*
+ * Write to the AR6000 through its diagnostic window.
+ * No cooperation from the Target is required for this.
+ */
+A_STATUS
+ar6000_WriteRegDiag(HIF_DEVICE *hifDevice, A_UINT32 *address, A_UINT32 *data)
+{
+ A_STATUS status;
+
+ /* set write data */
+ status = HIFReadWrite(hifDevice,
+ WINDOW_DATA_ADDRESS,
+ (A_UCHAR *)data,
+ sizeof(A_UINT32),
+ HIF_WR_SYNC_BYTE_INC,
+ NULL);
+ if (status != A_OK) {
+ AR_DEBUG_PRINTF(ATH_LOG_ERR, ("Cannot write 0x%x to WINDOW_DATA_ADDRESS\n", *data));
+ return status;
+ }
+
+ /* set window register, which starts the write cycle */
+ return ar6000_SetAddressWindowRegister(hifDevice,
+ WINDOW_WRITE_ADDR_ADDRESS,
+ *address);
+}
+
+A_STATUS
+ar6000_ReadDataDiag(HIF_DEVICE *hifDevice, A_UINT32 address,
+ A_UCHAR *data, A_UINT32 length)
+{
+ A_UINT32 count;
+ A_STATUS status = A_OK;
+
+ for (count = 0; count < length; count += 4, address += 4) {
+ if ((status = ar6000_ReadRegDiag(hifDevice, &address,
+ (A_UINT32 *)&data[count])) != A_OK)
+ {
+ break;
+ }
+ }
+
+ return status;
+}
+
+A_STATUS
+ar6000_WriteDataDiag(HIF_DEVICE *hifDevice, A_UINT32 address,
+ A_UCHAR *data, A_UINT32 length)
+{
+ A_UINT32 count;
+ A_STATUS status = A_OK;
+
+ for (count = 0; count < length; count += 4, address += 4) {
+ if ((status = ar6000_WriteRegDiag(hifDevice, &address,
+ (A_UINT32 *)&data[count])) != A_OK)
+ {
+ break;
+ }
+ }
+
+ return status;
+}
+
+A_STATUS
+ar6000_reset_device_skipflash(HIF_DEVICE *hifDevice)
+{
+ int i;
+ struct forceROM_s {
+ A_UINT32 addr;
+ A_UINT32 data;
+ };
+ struct forceROM_s *ForceROM;
+ int szForceROM;
+ A_UINT32 instruction;
+
+ static struct forceROM_s ForceROM_REV2[] = {
+ /* NB: This works for old REV2 ROM (old). */
+ {0x00001ff0, 0x175b0027}, /* jump instruction at 0xa0001ff0 */
+ {0x00001ff4, 0x00000000}, /* nop instruction at 0xa0001ff4 */
+
+ {MC_REMAP_TARGET_ADDRESS, 0x00001ff0}, /* remap to 0xa0001ff0 */
+ {MC_REMAP_COMPARE_ADDRESS, 0x01000040},/* ...from 0xbfc00040 */
+ {MC_REMAP_SIZE_ADDRESS, 0x00000000}, /* ...1 cache line */
+ {MC_REMAP_VALID_ADDRESS, 0x00000001}, /* ...remap is valid */
+
+ {LOCAL_COUNT_ADDRESS+0x10, 0}, /* clear BMI credit counter */
+
+ {RESET_CONTROL_ADDRESS, RESET_CONTROL_WARM_RST_MASK},
+ };
+
+ static struct forceROM_s ForceROM_NEW[] = {
+ /* NB: This works for AR6000 ROM REV3 and beyond. */
+ {LOCAL_SCRATCH_ADDRESS, AR6K_OPTION_IGNORE_FLASH},
+ {LOCAL_COUNT_ADDRESS+0x10, 0}, /* clear BMI credit counter */
+ {RESET_CONTROL_ADDRESS, RESET_CONTROL_WARM_RST_MASK},
+ };
+
+ /*
+ * Examine a semi-arbitrary instruction that's different
+ * in REV2 and other revisions.
+ * NB: If a Host port does not require simultaneous support
+ * for multiple revisions of Target ROM, this code can be elided.
+ */
+ (void)ar6000_ReadDataDiag(hifDevice, 0x01000040,
+ (A_UCHAR *)&instruction, 4);
+
+ AR_DEBUG_PRINTF(ATH_LOG_ERR, ("instruction=0x%x\n", instruction));
+
+ if (instruction == 0x3c1aa200) {
+ /* It's an old ROM */
+ ForceROM = ForceROM_REV2;
+ szForceROM = sizeof(ForceROM_REV2)/sizeof(*ForceROM);
+ AR_DEBUG_PRINTF(ATH_LOG_ERR, ("Using OLD method\n"));
+ } else {
+ ForceROM = ForceROM_NEW;
+ szForceROM = sizeof(ForceROM_NEW)/sizeof(*ForceROM);
+ AR_DEBUG_PRINTF(ATH_LOG_ERR, ("Using NEW method\n"));
+ }
+
+ AR_DEBUG_PRINTF(ATH_LOG_ERR, ("Force Target to execute from ROM....\n"));
+ for (i = 0; i < szForceROM; i++)
+ {
+ if (ar6000_WriteRegDiag(hifDevice,
+ &ForceROM[i].addr,
+ &ForceROM[i].data) != A_OK)
+ {
+ AR_DEBUG_PRINTF(ATH_LOG_ERR, ("Cannot force Target to execute ROM!\n"));
+ return A_ERROR;
+ }
+ }
+
+ msleep(50); /* delay to allow dragon to come to BMI phase */
+ return A_OK;
+}
+
+/* reset device */
+A_STATUS ar6000_reset_device(HIF_DEVICE *hifDevice, A_UINT32 TargetType)
+{
+
+#if !defined(DWSIM)
+ A_STATUS status = A_OK;
+ A_UINT32 address;
+ A_UINT32 data;
+
+ do {
+
+ // address = RESET_CONTROL_ADDRESS;
+ data = RESET_CONTROL_COLD_RST_MASK;
+
+ /* Hardcode the address of RESET_CONTROL_ADDRESS based on the target type */
+ if (TargetType == TARGET_TYPE_AR6001) {
+ address = 0x0C000000;
+ } else {
+ if (TargetType == TARGET_TYPE_AR6002) {
+ address = 0x00004000;
+ } else {
+ A_ASSERT(0);
+ }
+ }
+
+ status = ar6000_WriteRegDiag(hifDevice, &address, &data);
+
+ if (A_FAILED(status)) {
+ break;
+ }
+
+ /*
+ * Read back the RESET CAUSE register to ensure that the cold reset
+ * went through.
+ */
+ msleep(2000); /* 2 second delay to allow things to settle down */
+
+
+ // address = RESET_CAUSE_ADDRESS;
+ /* Hardcode the address of RESET_CAUSE_ADDRESS based on the target type */
+ if (TargetType == TARGET_TYPE_AR6001) {
+ address = 0x0C0000CC;
+ } else {
+ if (TargetType == TARGET_TYPE_AR6002) {
+ address = 0x000040C0;
+ } else {
+ A_ASSERT(0);
+ }
+ }
+
+ data = 0;
+ status = ar6000_ReadRegDiag(hifDevice, &address, &data);
+
+ if (A_FAILED(status)) {
+ break;
+ }
+
+ AR_DEBUG_PRINTF(ATH_LOG_ERR, ("Reset Cause readback: 0x%X \n",data));
+ data &= RESET_CAUSE_LAST_MASK;
+ if (data != 2) {
+ AR_DEBUG_PRINTF(ATH_LOG_ERR, ("Unable to cold reset the target \n"));
+ }
+
+ } while (FALSE);
+
+ if (A_FAILED(status)) {
+ AR_DEBUG_PRINTF(ATH_LOG_ERR, ("Failed to reset target \n"));
+ }
+#endif
+ return A_OK;
+}
+
+#define REG_DUMP_COUNT_AR6001 38 /* WORDs, derived from AR6001_regdump.h */
+#define REG_DUMP_COUNT_AR6002 32 /* WORDs, derived from AR6002_regdump.h */
+
+
+#if REG_DUMP_COUNT_AR6001 <= REG_DUMP_COUNT_AR6002
+#define REGISTER_DUMP_LEN_MAX REG_DUMP_COUNT_AR6002
+#else
+#define REGISTER_DUMP_LEN_MAX REG_DUMP_COUNT_AR6001
+#endif
+
+void ar6000_dump_target_assert_info(HIF_DEVICE *hifDevice, A_UINT32 TargetType)
+{
+ A_UINT32 address;
+ A_UINT32 regDumpArea = 0;
+ A_STATUS status;
+ A_UINT32 regDumpValues[REGISTER_DUMP_LEN_MAX];
+ A_UINT32 regDumpCount = 0;
+ A_UINT32 i;
+
+ do {
+
+ /* the reg dump pointer is copied to the host interest area */
+ address = HOST_INTEREST_ITEM_ADDRESS(TargetType, hi_failure_state);
+
+ if (TargetType == TARGET_TYPE_AR6001) {
+ /* for AR6001, this is a fixed location because the ptr is actually stuck in cache,
+ * this may be fixed in later firmware versions */
+ address = 0x18a0;
+ regDumpCount = REG_DUMP_COUNT_AR6001;
+
+ } else if (TargetType == TARGET_TYPE_AR6002) {
+
+ regDumpCount = REG_DUMP_COUNT_AR6002;
+
+ } else {
+ A_ASSERT(0);
+ }
+
+ /* read RAM location through diagnostic window */
+ status = ar6000_ReadRegDiag(hifDevice, &address, &regDumpArea);
+
+ if (A_FAILED(status)) {
+ AR_DEBUG_PRINTF(ATH_DEBUG_ERR,("AR6K: Failed to get ptr to register dump area \n"));
+ break;
+ }
+
+ AR_DEBUG_PRINTF(ATH_DEBUG_ERR,("AR6K: Location of register dump data: 0x%X \n",regDumpArea));
+
+ if (regDumpArea == 0) {
+ /* no reg dump */
+ break;
+ }
+
+ if (TargetType == TARGET_TYPE_AR6001) {
+ regDumpArea &= 0x0FFFFFFF; /* convert to physical address in target memory */
+ }
+
+ /* fetch register dump data */
+ status = ar6000_ReadDataDiag(hifDevice,
+ regDumpArea,
+ (A_UCHAR *)&regDumpValues[0],
+ regDumpCount * (sizeof(A_UINT32)));
+
+ if (A_FAILED(status)) {
+ AR_DEBUG_PRINTF(ATH_DEBUG_ERR,("AR6K: Failed to get register dump \n"));
+ break;
+ }
+
+ AR_DEBUG_PRINTF(ATH_DEBUG_ERR,("AR6K: Register Dump: \n"));
+
+ for (i = 0; i < regDumpCount; i++) {
+ AR_DEBUG_PRINTF(ATH_DEBUG_ERR,(" %d : 0x%8.8X \n",i, regDumpValues[i]));
+ }
+
+ } while (FALSE);
+
+}
+
diff --git a/drivers/ar6000/miscdrv/credit_dist.c b/drivers/ar6000/miscdrv/credit_dist.c
new file mode 100644
index 00000000000..8d37d627203
--- /dev/null
+++ b/drivers/ar6000/miscdrv/credit_dist.c
@@ -0,0 +1,346 @@
+
+/*
+ *
+ * Copyright (c) 2004-2007 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 "a_osapi.h"
+#include "a_debug.h"
+#include "htc_api.h"
+#include "common_drv.h"
+
+/********* CREDIT DISTRIBUTION FUNCTIONS ******************************************/
+
+#define NO_VO_SERVICE 1 /* currently WMI only uses 3 data streams, so we leave VO service inactive */
+
+#ifdef NO_VO_SERVICE
+#define DATA_SVCS_USED 3
+#else
+#define DATA_SVCS_USED 4
+#endif
+
+static void RedistributeCredits(COMMON_CREDIT_STATE_INFO *pCredInfo,
+ HTC_ENDPOINT_CREDIT_DIST *pEPDistList);
+
+static void SeekCredits(COMMON_CREDIT_STATE_INFO *pCredInfo,
+ HTC_ENDPOINT_CREDIT_DIST *pEPDistList);
+
+/* reduce an ep's credits back to a set limit */
+static INLINE void ReduceCredits(COMMON_CREDIT_STATE_INFO *pCredInfo,
+ HTC_ENDPOINT_CREDIT_DIST *pEpDist,
+ int Limit)
+{
+ int credits;
+
+ /* set the new limit */
+ pEpDist->TxCreditsAssigned = Limit;
+
+ if (pEpDist->TxCredits <= Limit) {
+ return;
+ }
+
+ /* figure out how much to take away */
+ credits = pEpDist->TxCredits - Limit;
+ /* take them away */
+ pEpDist->TxCredits -= credits;
+ pCredInfo->CurrentFreeCredits += credits;
+}
+
+/* give an endpoint some credits from the free credit pool */
+#define GiveCredits(pCredInfo,pEpDist,credits) \
+{ \
+ (pEpDist)->TxCredits += (credits); \
+ (pEpDist)->TxCreditsAssigned += (credits); \
+ (pCredInfo)->CurrentFreeCredits -= (credits); \
+}
+
+
+/* default credit init callback.
+ * This function is called in the context of HTCStart() to setup initial (application-specific)
+ * credit distributions */
+static void ar6000_credit_init(void *Context,
+ HTC_ENDPOINT_CREDIT_DIST *pEPList,
+ int TotalCredits)
+{
+ HTC_ENDPOINT_CREDIT_DIST *pCurEpDist;
+ int count;
+ COMMON_CREDIT_STATE_INFO *pCredInfo = (COMMON_CREDIT_STATE_INFO *)Context;
+
+ pCredInfo->CurrentFreeCredits = TotalCredits;
+ pCredInfo->TotalAvailableCredits = TotalCredits;
+
+ pCurEpDist = pEPList;
+
+ /* run through the list and initialize */
+ while (pCurEpDist != NULL) {
+
+ /* set minimums for each endpoint */
+ pCurEpDist->TxCreditsMin = pCurEpDist->TxCreditsPerMaxMsg;
+
+ if (pCurEpDist->ServiceID == WMI_CONTROL_SVC) {
+ /* give control service some credits */
+ GiveCredits(pCredInfo,pCurEpDist,pCurEpDist->TxCreditsMin);
+ /* control service is always marked active, it never goes inactive EVER */
+ SET_EP_ACTIVE(pCurEpDist);
+ } else if (pCurEpDist->ServiceID == WMI_DATA_BK_SVC) {
+ /* this is the lowest priority data endpoint, save this off for easy access */
+ pCredInfo->pLowestPriEpDist = pCurEpDist;
+ }
+
+ /* Streams have to be created (explicit | implicit)for all kinds
+ * of traffic. BE endpoints are also inactive in the beginning.
+ * When BE traffic starts it creates implicit streams that
+ * redistributes credits.
+ */
+
+ /* note, all other endpoints have minimums set but are initially given NO credits.
+ * Credits will be distributed as traffic activity demands */
+ pCurEpDist = pCurEpDist->pNext;
+ }
+
+ if (pCredInfo->CurrentFreeCredits <= 0) {
+ AR_DEBUG_PRINTF(ATH_LOG_INF, ("Not enough credits (%d) to do credit distributions \n", TotalCredits));
+ A_ASSERT(FALSE);
+ return;
+ }
+
+ /* reset list */
+ pCurEpDist = pEPList;
+ /* now run through the list and set max operating credit limits for everyone */
+ while (pCurEpDist != NULL) {
+ if (pCurEpDist->ServiceID == WMI_CONTROL_SVC) {
+ /* control service max is just 1 max message */
+ pCurEpDist->TxCreditsNorm = pCurEpDist->TxCreditsPerMaxMsg;
+ } else {
+ /* for the remaining data endpoints, we assume that each TxCreditsPerMaxMsg are
+ * the same.
+ * We use a simple calculation here, we take the remaining credits and
+ * determine how many max messages this can cover and then set each endpoint's
+ * normal value equal to half this amount.
+ * */
+ count = (pCredInfo->CurrentFreeCredits/pCurEpDist->TxCreditsPerMaxMsg) * pCurEpDist->TxCreditsPerMaxMsg;
+ count = count >> 1;
+ count = max(count,pCurEpDist->TxCreditsPerMaxMsg);
+ /* set normal */
+ pCurEpDist->TxCreditsNorm = count;
+
+ }
+ pCurEpDist = pCurEpDist->pNext;
+ }
+
+}
+
+
+/* default credit distribution callback
+ * This callback is invoked whenever endpoints require credit distributions.
+ * A lock is held while this function is invoked, this function shall NOT block.
+ * The pEPDistList is a list of distribution structures in prioritized order as
+ * defined by the call to the HTCSetCreditDistribution() api.
+ *
+ */
+static void ar6000_credit_distribute(void *Context,
+ HTC_ENDPOINT_CREDIT_DIST *pEPDistList,
+ HTC_CREDIT_DIST_REASON Reason)
+{
+ HTC_ENDPOINT_CREDIT_DIST *pCurEpDist;
+ COMMON_CREDIT_STATE_INFO *pCredInfo = (COMMON_CREDIT_STATE_INFO *)Context;
+
+ switch (Reason) {
+ case HTC_CREDIT_DIST_SEND_COMPLETE :
+ pCurEpDist = pEPDistList;
+ /* we are given the start of the endpoint distribution list.
+ * There may be one or more endpoints to service.
+ * Run through the list and distribute credits */
+ while (pCurEpDist != NULL) {
+
+ if (pCurEpDist->TxCreditsToDist > 0) {
+ /* return the credits back to the endpoint */
+ pCurEpDist->TxCredits += pCurEpDist->TxCreditsToDist;
+ /* always zero out when we are done */
+ pCurEpDist->TxCreditsToDist = 0;
+
+ if (pCurEpDist->TxCredits > pCurEpDist->TxCreditsAssigned) {
+ /* reduce to the assigned limit, previous credit reductions
+ * could have caused the limit to change */
+ ReduceCredits(pCredInfo, pCurEpDist, pCurEpDist->TxCreditsAssigned);
+ }
+
+ if (pCurEpDist->TxCredits > pCurEpDist->TxCreditsNorm) {
+ /* oversubscribed endpoints need to reduce back to normal */
+ ReduceCredits(pCredInfo, pCurEpDist, pCurEpDist->TxCreditsNorm);
+ }
+ }
+
+ pCurEpDist = pCurEpDist->pNext;
+ }
+
+ A_ASSERT(pCredInfo->CurrentFreeCredits <= pCredInfo->TotalAvailableCredits);
+
+ break;
+
+ case HTC_CREDIT_DIST_ACTIVITY_CHANGE :
+ RedistributeCredits(pCredInfo,pEPDistList);
+ break;
+ case HTC_CREDIT_DIST_SEEK_CREDITS :
+ SeekCredits(pCredInfo,pEPDistList);
+ break;
+ case HTC_DUMP_CREDIT_STATE :
+ AR_DEBUG_PRINTF(ATH_LOG_INF, ("Credit Distribution, total : %d, free : %d\n",
+ pCredInfo->TotalAvailableCredits, pCredInfo->CurrentFreeCredits));
+ break;
+ default:
+ break;
+
+ }
+
+}
+
+/* redistribute credits based on activity change */
+static void RedistributeCredits(COMMON_CREDIT_STATE_INFO *pCredInfo,
+ HTC_ENDPOINT_CREDIT_DIST *pEPDistList)
+{
+ HTC_ENDPOINT_CREDIT_DIST *pCurEpDist = pEPDistList;
+
+ /* walk through the list and remove credits from inactive endpoints */
+ while (pCurEpDist != NULL) {
+
+ if (pCurEpDist->ServiceID != WMI_CONTROL_SVC) {
+ if (!IS_EP_ACTIVE(pCurEpDist)) {
+ /* EP is inactive, reduce credits back to zero */
+ ReduceCredits(pCredInfo, pCurEpDist, 0);
+ }
+ }
+
+ /* NOTE in the active case, we do not need to do anything further,
+ * when an EP goes active and needs credits, HTC will call into
+ * our distribution function using a reason code of HTC_CREDIT_DIST_SEEK_CREDITS */
+
+ pCurEpDist = pCurEpDist->pNext;
+ }
+
+ A_ASSERT(pCredInfo->CurrentFreeCredits <= pCredInfo->TotalAvailableCredits);
+
+}
+
+/* HTC has an endpoint that needs credits, pEPDist is the endpoint in question */
+static void SeekCredits(COMMON_CREDIT_STATE_INFO *pCredInfo,
+ HTC_ENDPOINT_CREDIT_DIST *pEPDist)
+{
+ HTC_ENDPOINT_CREDIT_DIST *pCurEpDist;
+ int credits = 0;
+ int need;
+
+ do {
+
+ if (pEPDist->ServiceID == WMI_CONTROL_SVC) {
+ /* we never oversubscribe on the control service, this is not
+ * a high performance path and the target never holds onto control
+ * credits for too long */
+ break;
+ }
+
+ /* for all other services, we follow a simple algorithm of
+ * 1. checking the free pool for credits
+ * 2. checking lower priority endpoints for credits to take */
+
+ if (pCredInfo->CurrentFreeCredits >= 2 * pEPDist->TxCreditsSeek) {
+ /* try to give more credits than it needs */
+ credits = 2 * pEPDist->TxCreditsSeek;
+ } else {
+ /* give what we can */
+ credits = min(pCredInfo->CurrentFreeCredits,pEPDist->TxCreditsSeek);
+ }
+
+ if (credits >= pEPDist->TxCreditsSeek) {
+ /* we found some to fullfill the seek request */
+ break;
+ }
+
+ /* we don't have enough in the free pool, try taking away from lower priority services
+ *
+ * The rule for taking away credits:
+ * 1. Only take from lower priority endpoints
+ * 2. Only take what is allocated above the minimum (never starve an endpoint completely)
+ * 3. Only take what you need.
+ *
+ * */
+
+ /* starting at the lowest priority */
+ pCurEpDist = pCredInfo->pLowestPriEpDist;
+
+ /* work backwards until we hit the endpoint again */
+ while (pCurEpDist != pEPDist) {
+ /* calculate how many we need so far */
+ need = pEPDist->TxCreditsSeek - pCredInfo->CurrentFreeCredits;
+
+ if ((pCurEpDist->TxCreditsAssigned - need) > pCurEpDist->TxCreditsMin) {
+ /* the current one has been allocated more than it's minimum and it
+ * has enough credits assigned above it's minimum to fullfill our need
+ * try to take away just enough to fullfill our need */
+ ReduceCredits(pCredInfo,
+ pCurEpDist,
+ pCurEpDist->TxCreditsAssigned - need);
+
+ if (pCredInfo->CurrentFreeCredits >= pEPDist->TxCreditsSeek) {
+ /* we have enough */
+ break;
+ }
+ }
+
+ pCurEpDist = pCurEpDist->pPrev;
+ }
+
+ /* return what we can get */
+ credits = min(pCredInfo->CurrentFreeCredits,pEPDist->TxCreditsSeek);
+
+ } while (FALSE);
+
+ /* did we find some credits? */
+ if (credits) {
+ /* give what we can */
+ GiveCredits(pCredInfo, pEPDist, credits);
+ }
+
+}
+
+/* initialize and setup credit distribution */
+A_STATUS ar6000_setup_credit_dist(HTC_HANDLE HTCHandle, COMMON_CREDIT_STATE_INFO *pCredInfo)
+{
+ HTC_SERVICE_ID servicepriority[5];
+
+ A_MEMZERO(pCredInfo,sizeof(COMMON_CREDIT_STATE_INFO));
+
+ servicepriority[0] = WMI_CONTROL_SVC; /* highest */
+ servicepriority[1] = WMI_DATA_VO_SVC;
+ servicepriority[2] = WMI_DATA_VI_SVC;
+ servicepriority[3] = WMI_DATA_BE_SVC;
+ servicepriority[4] = WMI_DATA_BK_SVC; /* lowest */
+
+ /* set callbacks and priority list */
+ HTCSetCreditDistribution(HTCHandle,
+ pCredInfo,
+ ar6000_credit_distribute,
+ ar6000_credit_init,
+ servicepriority,
+ 5);
+
+ return A_OK;
+}
+