drivers/gpu/drm/img-rogue/tlintern.c - chromiumos/third_party/kernel - Git at Google

 /*************************************************************************/ /*!
 @File
 @Title          Transport Layer kernel side API implementation.
 @Copyright      Copyright (c) Imagination Technologies Ltd. All Rights Reserved
 @Description    Transport Layer functions available to driver components in
                 the driver.
 @License        Dual MIT/GPLv2

 The contents of this file are subject to the MIT license as set out below.

 Permission is hereby granted, free of charge, to any person obtaining a copy
 of this software and associated documentation files (the "Software"), to deal
 in the Software without restriction, including without limitation the rights
 to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 copies of the Software, and to permit persons to whom the Software is
 furnished to do so, subject to the following conditions:

 The above copyright notice and this permission notice shall be included in
 all copies or substantial portions of the Software.

 Alternatively, the contents of this file may be used under the terms of
 the GNU General Public License Version 2 ("GPL") in which case the provisions
 of GPL are applicable instead of those above.

 If you wish to allow use of your version of this file only under the terms of
 GPL, and not to allow others to use your version of this file under the terms
 of the MIT license, indicate your decision by deleting the provisions above
 and replace them with the notice and other provisions required by GPL as set
 out in the file called "GPL-COPYING" included in this distribution. If you do
 not delete the provisions above, a recipient may use your version of this file
 under the terms of either the MIT license or GPL.

 This License is also included in this distribution in the file called
 "MIT-COPYING".

 EXCEPT AS OTHERWISE STATED IN A NEGOTIATED AGREEMENT: (A) THE SOFTWARE IS
 PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING
 BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR
 PURPOSE AND NONINFRINGEMENT; AND (B) IN NO EVENT SHALL THE AUTHORS OR
 COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
 IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
 CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 */ /**************************************************************************/
 //#define PVR_DPF_FUNCTION_TRACE_ON 1
 #undef PVR_DPF_FUNCTION_TRACE_ON
 #include "pvr_debug.h"

 #include "allocmem.h"
 #include "pvrsrv_error.h"
 #include "osfunc.h"
 #include "devicemem.h"

 #include "pvrsrv_tlcommon.h"
 #include "tlintern.h"

 /*
  * Make functions
  */
 PTL_STREAM_DESC
 TLMakeStreamDesc(PTL_SNODE f1, IMG_UINT32 f2, IMG_HANDLE f3)
 {
 	PTL_STREAM_DESC ps = OSAllocZMem(sizeof(TL_STREAM_DESC));
 	if (ps == NULL)
 	{
 		return NULL;
 	}
 	ps->psNode = f1;
 	ps->ui32Flags = f2;
 	ps->hReadEvent = f3;
 	ps->uiRefCount = 1;
 	return ps;
 }

 PTL_SNODE
 TLMakeSNode(IMG_HANDLE f2, TL_STREAM *f3, TL_STREAM_DESC *f4)
 {
 	PTL_SNODE ps = OSAllocZMem(sizeof(TL_SNODE));
 	if (ps == NULL)
 	{
 		return NULL;
 	}
 	ps->hReadEventObj = f2;
 	ps->psStream = f3;
 	ps->psRDesc = f4;
 	f3->psNode = ps;
 	return ps;
 }

 /*
  * Transport Layer Global top variables and functions
  */
 static TL_GLOBAL_DATA  sTLGlobalData = { 0 };

 TL_GLOBAL_DATA *TLGGD(void)	// TLGetGlobalData()
 {
 	return &sTLGlobalData;
 }

 /* TLInit must only be called once at driver initialisation for one device.
  * An assert is provided to check this condition on debug builds.
  */
 PVRSRV_ERROR
 TLInit(PVRSRV_DEVICE_NODE *psDevNode)
 {
 	PVRSRV_ERROR eError;

 	PVR_DPF_ENTERED;

 	PVR_ASSERT(psDevNode);

 	/*
 	 * The Transport Layer is designed to work in a single device system but
 	 * this function will be called multiple times in a multi-device system.
 	 * Return an error in this case.
 	 */
 	if (sTLGlobalData.psRgxDevNode)
 	{
 		return PVRSRV_ERROR_INIT_FAILURE;
 	}

 	/* Store the RGX device node for later use in devmem buffer allocations */
 	sTLGlobalData.psRgxDevNode = (void*)psDevNode;

 	/* Allocate a lock for TL global data, to be used while updating the TL data.
 	 * This is for making TL global data muti-thread safe */
 	eError = OSLockCreate (&sTLGlobalData.hTLGDLock, LOCK_TYPE_PASSIVE);
 	if (eError != PVRSRV_OK)
 	{
 		goto e0;
 	}

 	/* Allocate the event object used to signal global TL events such as
 	 * new stream created */
 	eError = OSEventObjectCreate("TLGlobalEventObj", &sTLGlobalData.hTLEventObj);
 	if (eError != PVRSRV_OK)
 	{
 		goto e1;
 	}

 	PVR_DPF_RETURN_OK;

 /* Don't allow the driver to start up on error */
 e1:
 	OSLockDestroy (sTLGlobalData.hTLGDLock);
 	sTLGlobalData.hTLGDLock = NULL;
 e0:
 	PVR_DPF_RETURN_RC (eError);
 }

 static void RemoveAndFreeStreamNode(PTL_SNODE psRemove)
 {
 	TL_GLOBAL_DATA*  psGD = TLGGD();
 	PTL_SNODE* 		 last;
 	PTL_SNODE 		 psn;
 	PVRSRV_ERROR     eError;

 	PVR_DPF_ENTERED;

 	// Unlink the stream node from the master list
 	PVR_ASSERT(psGD->psHead);
 	last = &psGD->psHead;
 	for (psn = psGD->psHead; psn; psn=psn->psNext)
 	{
 		if (psn == psRemove)
 		{
 			/* Other calling code may have freed and zero'd the pointers */
 			if (psn->psRDesc)
 			{
 				OSFreeMem(psn->psRDesc);
 				psn->psRDesc = NULL;
 			}
 			if (psn->psStream)
 			{
 				OSFreeMem(psn->psStream);
 				psn->psStream = NULL;
 			}
 			*last = psn->psNext;
 			break;
 		}
 		last = &psn->psNext;
 	}

 	// Release the event list object owned by the stream node
 	if (psRemove->hReadEventObj)
 	{
 		eError = OSEventObjectDestroy(psRemove->hReadEventObj);
 		PVR_LOG_IF_ERROR(eError, "OSEventObjectDestroy");

 		psRemove->hReadEventObj = NULL;
 	}

 	// Release the memory of the stream node
 	OSFreeMem(psRemove);

 	PVR_DPF_RETURN;
 }

 void
 TLDeInit(PVRSRV_DEVICE_NODE *psDevNode)
 {
 	PVR_DPF_ENTERED;

 	if (sTLGlobalData.psRgxDevNode != psDevNode)
 	{
 		PVR_DPF_RETURN;
 	}

 	if (sTLGlobalData.uiClientCnt)
 	{
 		PVR_DPF((PVR_DBG_ERROR, "TLDeInit transport layer but %d client streams are still connected", sTLGlobalData.uiClientCnt));
 		sTLGlobalData.uiClientCnt = 0;
 	}

 	/* Clean up the SNODE list */
 	if (sTLGlobalData.psHead)
 	{
 		while (sTLGlobalData.psHead)
 		{
 			RemoveAndFreeStreamNode(sTLGlobalData.psHead);
 		}
 		/* Leave psHead NULL on loop exit */
 	}

 	/* Clean up the TL global event object */
 	if (sTLGlobalData.hTLEventObj)
 	{
 		OSEventObjectDestroy(sTLGlobalData.hTLEventObj);
 		sTLGlobalData.hTLEventObj = NULL;
 	}

 	/* Destroy the TL global data lock */
 	if (sTLGlobalData.hTLGDLock)
 	{
 		OSLockDestroy (sTLGlobalData.hTLGDLock);
 		sTLGlobalData.hTLGDLock = NULL;
 	}

 	sTLGlobalData.psRgxDevNode = NULL;

 	PVR_DPF_RETURN;
 }

 PVRSRV_DEVICE_NODE*
 TLGetGlobalRgxDevice(void)
 {
 	PVRSRV_DEVICE_NODE *p = (PVRSRV_DEVICE_NODE*)(TLGGD()->psRgxDevNode);
 	if (!p)
 	{
 		PVR_DPF((PVR_DBG_ERROR, "TLGetGlobalRgxDevice() NULL node ptr, TL " \
 				"can not be used when no RGX device has been found"));
 		PVR_ASSERT(p);
 	}
 	return p;
 }

 void TLAddStreamNode(PTL_SNODE psAdd)
 {
 	PVR_DPF_ENTERED;

 	PVR_ASSERT(psAdd);
 	psAdd->psNext = TLGGD()->psHead;
 	TLGGD()->psHead = psAdd;

 	PVR_DPF_RETURN;
 }

 PTL_SNODE TLFindStreamNodeByName(const IMG_CHAR *pszName)
 {
 	TL_GLOBAL_DATA*  psGD = TLGGD();
 	PTL_SNODE 		 psn;

 	PVR_DPF_ENTERED;

 	PVR_ASSERT(pszName);

 	for (psn = psGD->psHead; psn; psn=psn->psNext)
 	{
 		if (psn->psStream && OSStringCompare(psn->psStream->szName, pszName)==0)
 		{
 			PVR_DPF_RETURN_VAL(psn);
 		}
 	}

 	PVR_DPF_RETURN_VAL(NULL);
 }

 PTL_SNODE TLFindStreamNodeByDesc(PTL_STREAM_DESC psDesc)
 {
 	TL_GLOBAL_DATA*  psGD = TLGGD();
 	PTL_SNODE 		 psn;

 	PVR_DPF_ENTERED;

 	PVR_ASSERT(psDesc);

 	for (psn = psGD->psHead; psn; psn=psn->psNext)
 	{
 		if (psn->psRDesc == psDesc || psn->psWDesc == psDesc)
 		{
 			PVR_DPF_RETURN_VAL(psn);
 		}
 	}
 	PVR_DPF_RETURN_VAL(NULL);
 }

 static inline IMG_BOOL IsDigit(IMG_CHAR c)
 {
 	return c >= '0' && c <= '9';
 }

 static inline IMG_BOOL ReadNumber(const IMG_CHAR *pszBuffer,
                                   IMG_UINT32 *pui32Number)
 {
 	IMG_CHAR acTmp[11] = {0}; // max 10 digits
 	IMG_UINT32 ui32Result;
 	IMG_UINT i;

 	for (i = 0; i < sizeof(acTmp) - 1; i++)
 	{
 		if (!IsDigit(*pszBuffer))
 			break;
 		acTmp[i] = *pszBuffer++;
 	}

 	/* if there are no digits or there is something after the number */
 	if (i == 0 || *pszBuffer != '\0')
 		return IMG_FALSE;

 	if (OSStringToUINT32(acTmp, 10, &ui32Result) != PVRSRV_OK)
 		return IMG_FALSE;

 	*pui32Number = ui32Result;

 	return IMG_TRUE;
 }

 /**
  * Matches pszPattern against pszName and stores results in pui32Numbers.
  *
  * @Input pszPattern this is a beginning part of the name string that should
  *                   be followed by a number.
  * @Input pszName name of the stream
  * @Output pui32Number will contain numbers from stream's name end e.g.
  *                     1234 for name abc_1234
  * @Return IMG_TRUE when a stream was found or IMG_FALSE if not
  */
 static IMG_BOOL MatchNamePattern(const IMG_CHAR *pszNamePattern,
                                  const IMG_CHAR *pszName,
                                  IMG_UINT32 *pui32Number)
 {
 	IMG_UINT uiPatternLen;

 	uiPatternLen = OSStringLength(pszNamePattern);

 	if (OSStringNCompare(pszNamePattern, pszName, uiPatternLen) != 0)
 		return IMG_FALSE;

 	return ReadNumber(pszName + uiPatternLen, pui32Number);
 }

 IMG_UINT32 TLDiscoverStreamNodes(const IMG_CHAR *pszNamePattern,
                                  IMG_UINT32 *pui32Streams,
                                  IMG_UINT32 ui32Max)
 {
 	TL_GLOBAL_DATA *psGD = TLGGD();
 	PTL_SNODE psn;
 	IMG_UINT32 ui32Count = 0;

 	PVR_ASSERT(pszNamePattern);

 	for (psn = psGD->psHead; psn; psn = psn->psNext)
 	{
 		IMG_UINT32 ui32Number = 0;

 		if (!MatchNamePattern(pszNamePattern, psn->psStream->szName,
 		                      &ui32Number))
 			continue;

 		if (pui32Streams != NULL)
 		{
 			if (ui32Count > ui32Max)
 				break;

 			pui32Streams[ui32Count] = ui32Number;
 		}

 		ui32Count++;
 	}

 	return ui32Count;
 }

 PTL_SNODE TLFindAndGetStreamNodeByDesc(PTL_STREAM_DESC psDesc)
 {
 	PTL_SNODE psn;

 	PVR_DPF_ENTERED;

 	psn = TLFindStreamNodeByDesc(psDesc);
 	if (psn == NULL)
 		PVR_DPF_RETURN_VAL(NULL);

 	PVR_ASSERT(psDesc == psn->psWDesc);

 	psn->uiWRefCount++;
 	psDesc->uiRefCount++;

 	PVR_DPF_RETURN_VAL(psn);
 }

 void TLReturnStreamNode(PTL_SNODE psNode)
 {
 	psNode->uiWRefCount--;
 	psNode->psWDesc->uiRefCount--;

 	PVR_ASSERT(psNode->uiWRefCount > 0);
 	PVR_ASSERT(psNode->psWDesc->uiRefCount > 0);
 }

 IMG_BOOL TLTryRemoveStreamAndFreeStreamNode(PTL_SNODE psRemove)
 {
 	PVR_DPF_ENTERED;

 	PVR_ASSERT(psRemove);

 	/* If there is a client connected to this stream, defer stream's deletion */
 	if (psRemove->psRDesc != NULL || psRemove->psWDesc != NULL)
 	{
 		PVR_DPF_RETURN_VAL (IMG_FALSE);
 	}

 	/* Remove stream from TL_GLOBAL_DATA's list and free stream node */
 	psRemove->psStream = NULL;
 	RemoveAndFreeStreamNode(psRemove);

 	PVR_DPF_RETURN_VAL (IMG_TRUE);
 }

 IMG_BOOL TLUnrefDescAndTryFreeStreamNode(PTL_SNODE psNodeToRemove,
                                           PTL_STREAM_DESC psSD)
 {
 	PVR_DPF_ENTERED;

 	PVR_ASSERT(psNodeToRemove);
 	PVR_ASSERT(psSD);

 	/* Decrement reference count. For descriptor obtained by reader it must
 	 * reach 0 (only single reader allowed) and for descriptors obtained by
 	 * writers it must reach value greater or equal to 0 (multiple writers
 	 * model). */
 	psSD->uiRefCount--;

 	if (psSD == psNodeToRemove->psRDesc)
 	{
 		PVR_ASSERT(0 == psSD->uiRefCount);
 		/* Remove stream descriptor (i.e. stream reader context) */
 		psNodeToRemove->psRDesc = NULL;
 	}
 	else if (psSD == psNodeToRemove->psWDesc)
 	{
 		PVR_ASSERT(0 <= psSD->uiRefCount);

 		psNodeToRemove->uiWRefCount--;

 		/* Remove stream descriptor if reference == 0 */
 		if (0 == psSD->uiRefCount)
 		{
 			psNodeToRemove->psWDesc = NULL;
 		}
 	}

 	/* Do not Free Stream Node if there is a write reference (a producer
 	 * context) to the stream */
 	if (NULL != psNodeToRemove->psRDesc || NULL != psNodeToRemove->psWDesc ||
 	    0 != psNodeToRemove->uiWRefCount)
 	{
 		PVR_DPF_RETURN_VAL (IMG_FALSE);
 	}

 	/* Make stream pointer NULL to prevent it from being destroyed in
 	 * RemoveAndFreeStreamNode Cleanup of stream should be done by the calling
 	 * context */
 	psNodeToRemove->psStream = NULL;
 	RemoveAndFreeStreamNode(psNodeToRemove);

 	PVR_DPF_RETURN_VAL (IMG_TRUE);
 }
	/************************************************************************/ /!
	@File
	@Title Transport Layer kernel side API implementation.
	@Copyright Copyright (c) Imagination Technologies Ltd. All Rights Reserved
	@Description Transport Layer functions available to driver components in
	the driver.
	@License Dual MIT/GPLv2

	The contents of this file are subject to the MIT license as set out below.

	Permission is hereby granted, free of charge, to any person obtaining a copy
	of this software and associated documentation files (the "Software"), to deal
	in the Software without restriction, including without limitation the rights
	to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
	copies of the Software, and to permit persons to whom the Software is
	furnished to do so, subject to the following conditions:

	The above copyright notice and this permission notice shall be included in
	all copies or substantial portions of the Software.

	Alternatively, the contents of this file may be used under the terms of
	the GNU General Public License Version 2 ("GPL") in which case the provisions
	of GPL are applicable instead of those above.

	If you wish to allow use of your version of this file only under the terms of
	GPL, and not to allow others to use your version of this file under the terms
	of the MIT license, indicate your decision by deleting the provisions above
	and replace them with the notice and other provisions required by GPL as set
	out in the file called "GPL-COPYING" included in this distribution. If you do
	not delete the provisions above, a recipient may use your version of this file
	under the terms of either the MIT license or GPL.

	This License is also included in this distribution in the file called
	"MIT-COPYING".

	EXCEPT AS OTHERWISE STATED IN A NEGOTIATED AGREEMENT: (A) THE SOFTWARE IS
	PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING
	BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR
	PURPOSE AND NONINFRINGEMENT; AND (B) IN NO EVENT SHALL THE AUTHORS OR
	COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
	IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
	CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
	/ /*************************************************************************/
	//#define PVR_DPF_FUNCTION_TRACE_ON 1
	#undef PVR_DPF_FUNCTION_TRACE_ON
	#include "pvr_debug.h"

	#include "allocmem.h"
	#include "pvrsrv_error.h"
	#include "osfunc.h"
	#include "devicemem.h"

	#include "pvrsrv_tlcommon.h"
	#include "tlintern.h"

	/*
	* Make functions
	*/
	PTL_STREAM_DESC
	TLMakeStreamDesc(PTL_SNODE f1, IMG_UINT32 f2, IMG_HANDLE f3)
	{
	PTL_STREAM_DESC ps = OSAllocZMem(sizeof(TL_STREAM_DESC));
	if (ps == NULL)
	{
	return NULL;
	}
	ps->psNode = f1;
	ps->ui32Flags = f2;
	ps->hReadEvent = f3;
	ps->uiRefCount = 1;
	return ps;
	}

	PTL_SNODE
	TLMakeSNode(IMG_HANDLE f2, TL_STREAM f3, TL_STREAM_DESC f4)
	{
	PTL_SNODE ps = OSAllocZMem(sizeof(TL_SNODE));
	if (ps == NULL)
	{
	return NULL;
	}
	ps->hReadEventObj = f2;
	ps->psStream = f3;
	ps->psRDesc = f4;
	f3->psNode = ps;
	return ps;
	}

	/*
	* Transport Layer Global top variables and functions
	*/
	static TL_GLOBAL_DATA sTLGlobalData = { 0 };

	TL_GLOBAL_DATA *TLGGD(void) // TLGetGlobalData()
	{
	return &sTLGlobalData;
	}

	/* TLInit must only be called once at driver initialisation for one device.
	* An assert is provided to check this condition on debug builds.
	*/
	PVRSRV_ERROR
	TLInit(PVRSRV_DEVICE_NODE *psDevNode)
	{
	PVRSRV_ERROR eError;

	PVR_DPF_ENTERED;

	PVR_ASSERT(psDevNode);

	/*
	* The Transport Layer is designed to work in a single device system but
	* this function will be called multiple times in a multi-device system.
	* Return an error in this case.
	*/
	if (sTLGlobalData.psRgxDevNode)
	{
	return PVRSRV_ERROR_INIT_FAILURE;
	}

	/* Store the RGX device node for later use in devmem buffer allocations */
	sTLGlobalData.psRgxDevNode = (void*)psDevNode;

	/* Allocate a lock for TL global data, to be used while updating the TL data.
	* This is for making TL global data muti-thread safe */
	eError = OSLockCreate (&sTLGlobalData.hTLGDLock, LOCK_TYPE_PASSIVE);
	if (eError != PVRSRV_OK)
	{
	goto e0;
	}

	/* Allocate the event object used to signal global TL events such as
	* new stream created */
	eError = OSEventObjectCreate("TLGlobalEventObj", &sTLGlobalData.hTLEventObj);
	if (eError != PVRSRV_OK)
	{
	goto e1;
	}

	PVR_DPF_RETURN_OK;

	/* Don't allow the driver to start up on error */
	e1:
	OSLockDestroy (sTLGlobalData.hTLGDLock);
	sTLGlobalData.hTLGDLock = NULL;
	e0:
	PVR_DPF_RETURN_RC (eError);
	}

	static void RemoveAndFreeStreamNode(PTL_SNODE psRemove)
	{
	TL_GLOBAL_DATA* psGD = TLGGD();
	PTL_SNODE* last;
	PTL_SNODE psn;
	PVRSRV_ERROR eError;

	PVR_DPF_ENTERED;

	// Unlink the stream node from the master list
	PVR_ASSERT(psGD->psHead);
	last = &psGD->psHead;
	for (psn = psGD->psHead; psn; psn=psn->psNext)
	{
	if (psn == psRemove)
	{
	/* Other calling code may have freed and zero'd the pointers */
	if (psn->psRDesc)
	{
	OSFreeMem(psn->psRDesc);
	psn->psRDesc = NULL;
	}
	if (psn->psStream)
	{
	OSFreeMem(psn->psStream);
	psn->psStream = NULL;
	}
	*last = psn->psNext;
	break;
	}
	last = &psn->psNext;
	}

	// Release the event list object owned by the stream node
	if (psRemove->hReadEventObj)
	{
	eError = OSEventObjectDestroy(psRemove->hReadEventObj);
	PVR_LOG_IF_ERROR(eError, "OSEventObjectDestroy");

	psRemove->hReadEventObj = NULL;
	}

	// Release the memory of the stream node
	OSFreeMem(psRemove);

	PVR_DPF_RETURN;
	}

	void
	TLDeInit(PVRSRV_DEVICE_NODE *psDevNode)
	{
	PVR_DPF_ENTERED;

	if (sTLGlobalData.psRgxDevNode != psDevNode)
	{
	PVR_DPF_RETURN;
	}

	if (sTLGlobalData.uiClientCnt)
	{
	PVR_DPF((PVR_DBG_ERROR, "TLDeInit transport layer but %d client streams are still connected", sTLGlobalData.uiClientCnt));
	sTLGlobalData.uiClientCnt = 0;
	}

	/* Clean up the SNODE list */
	if (sTLGlobalData.psHead)
	{
	while (sTLGlobalData.psHead)
	{
	RemoveAndFreeStreamNode(sTLGlobalData.psHead);
	}
	/* Leave psHead NULL on loop exit */
	}

	/* Clean up the TL global event object */
	if (sTLGlobalData.hTLEventObj)
	{
	OSEventObjectDestroy(sTLGlobalData.hTLEventObj);
	sTLGlobalData.hTLEventObj = NULL;
	}

	/* Destroy the TL global data lock */
	if (sTLGlobalData.hTLGDLock)
	{
	OSLockDestroy (sTLGlobalData.hTLGDLock);
	sTLGlobalData.hTLGDLock = NULL;
	}

	sTLGlobalData.psRgxDevNode = NULL;

	PVR_DPF_RETURN;
	}

	PVRSRV_DEVICE_NODE*
	TLGetGlobalRgxDevice(void)
	{
	PVRSRV_DEVICE_NODE p = (PVRSRV_DEVICE_NODE)(TLGGD()->psRgxDevNode);
	if (!p)
	{
	PVR_DPF((PVR_DBG_ERROR, "TLGetGlobalRgxDevice() NULL node ptr, TL " \
	"can not be used when no RGX device has been found"));
	PVR_ASSERT(p);
	}
	return p;
	}

	void TLAddStreamNode(PTL_SNODE psAdd)
	{
	PVR_DPF_ENTERED;

	PVR_ASSERT(psAdd);
	psAdd->psNext = TLGGD()->psHead;
	TLGGD()->psHead = psAdd;

	PVR_DPF_RETURN;
	}

	PTL_SNODE TLFindStreamNodeByName(const IMG_CHAR *pszName)
	{
	TL_GLOBAL_DATA* psGD = TLGGD();
	PTL_SNODE psn;

	PVR_DPF_ENTERED;

	PVR_ASSERT(pszName);

	for (psn = psGD->psHead; psn; psn=psn->psNext)
	{
	if (psn->psStream && OSStringCompare(psn->psStream->szName, pszName)==0)
	{
	PVR_DPF_RETURN_VAL(psn);
	}
	}

	PVR_DPF_RETURN_VAL(NULL);
	}

	PTL_SNODE TLFindStreamNodeByDesc(PTL_STREAM_DESC psDesc)
	{
	TL_GLOBAL_DATA* psGD = TLGGD();
	PTL_SNODE psn;

	PVR_DPF_ENTERED;

	PVR_ASSERT(psDesc);

	for (psn = psGD->psHead; psn; psn=psn->psNext)
	{
	if (psn->psRDesc == psDesc \|\| psn->psWDesc == psDesc)
	{
	PVR_DPF_RETURN_VAL(psn);
	}
	}
	PVR_DPF_RETURN_VAL(NULL);
	}

	static inline IMG_BOOL IsDigit(IMG_CHAR c)
	{
	return c >= '0' && c <= '9';
	}

	static inline IMG_BOOL ReadNumber(const IMG_CHAR *pszBuffer,
	IMG_UINT32 *pui32Number)
	{
	IMG_CHAR acTmp[11] = {0}; // max 10 digits
	IMG_UINT32 ui32Result;
	IMG_UINT i;

	for (i = 0; i < sizeof(acTmp) - 1; i++)
	{
	if (!IsDigit(*pszBuffer))
	break;
	acTmp[i] = *pszBuffer++;
	}

	/* if there are no digits or there is something after the number */
	if (i == 0 \|\| *pszBuffer != '\0')
	return IMG_FALSE;

	if (OSStringToUINT32(acTmp, 10, &ui32Result) != PVRSRV_OK)
	return IMG_FALSE;

	*pui32Number = ui32Result;

	return IMG_TRUE;
	}

	/**
	* Matches pszPattern against pszName and stores results in pui32Numbers.
	*
	* @Input pszPattern this is a beginning part of the name string that should
	* be followed by a number.
	* @Input pszName name of the stream
	* @Output pui32Number will contain numbers from stream's name end e.g.
	* 1234 for name abc_1234
	* @Return IMG_TRUE when a stream was found or IMG_FALSE if not
	*/
	static IMG_BOOL MatchNamePattern(const IMG_CHAR *pszNamePattern,
	const IMG_CHAR *pszName,
	IMG_UINT32 *pui32Number)
	{
	IMG_UINT uiPatternLen;

	uiPatternLen = OSStringLength(pszNamePattern);

	if (OSStringNCompare(pszNamePattern, pszName, uiPatternLen) != 0)
	return IMG_FALSE;

	return ReadNumber(pszName + uiPatternLen, pui32Number);
	}

	IMG_UINT32 TLDiscoverStreamNodes(const IMG_CHAR *pszNamePattern,
	IMG_UINT32 *pui32Streams,
	IMG_UINT32 ui32Max)
	{
	TL_GLOBAL_DATA *psGD = TLGGD();
	PTL_SNODE psn;
	IMG_UINT32 ui32Count = 0;

	PVR_ASSERT(pszNamePattern);

	for (psn = psGD->psHead; psn; psn = psn->psNext)
	{
	IMG_UINT32 ui32Number = 0;

	if (!MatchNamePattern(pszNamePattern, psn->psStream->szName,
	&ui32Number))
	continue;

	if (pui32Streams != NULL)
	{
	if (ui32Count > ui32Max)
	break;

	pui32Streams[ui32Count] = ui32Number;
	}

	ui32Count++;
	}

	return ui32Count;
	}

	PTL_SNODE TLFindAndGetStreamNodeByDesc(PTL_STREAM_DESC psDesc)
	{
	PTL_SNODE psn;

	PVR_DPF_ENTERED;

	psn = TLFindStreamNodeByDesc(psDesc);
	if (psn == NULL)
	PVR_DPF_RETURN_VAL(NULL);

	PVR_ASSERT(psDesc == psn->psWDesc);

	psn->uiWRefCount++;
	psDesc->uiRefCount++;

	PVR_DPF_RETURN_VAL(psn);
	}

	void TLReturnStreamNode(PTL_SNODE psNode)
	{
	psNode->uiWRefCount--;
	psNode->psWDesc->uiRefCount--;

	PVR_ASSERT(psNode->uiWRefCount > 0);
	PVR_ASSERT(psNode->psWDesc->uiRefCount > 0);
	}

	IMG_BOOL TLTryRemoveStreamAndFreeStreamNode(PTL_SNODE psRemove)
	{
	PVR_DPF_ENTERED;

	PVR_ASSERT(psRemove);

	/* If there is a client connected to this stream, defer stream's deletion */
	if (psRemove->psRDesc != NULL \|\| psRemove->psWDesc != NULL)
	{
	PVR_DPF_RETURN_VAL (IMG_FALSE);
	}

	/* Remove stream from TL_GLOBAL_DATA's list and free stream node */
	psRemove->psStream = NULL;
	RemoveAndFreeStreamNode(psRemove);

	PVR_DPF_RETURN_VAL (IMG_TRUE);
	}

	IMG_BOOL TLUnrefDescAndTryFreeStreamNode(PTL_SNODE psNodeToRemove,
	PTL_STREAM_DESC psSD)
	{
	PVR_DPF_ENTERED;

	PVR_ASSERT(psNodeToRemove);
	PVR_ASSERT(psSD);

	/* Decrement reference count. For descriptor obtained by reader it must
	* reach 0 (only single reader allowed) and for descriptors obtained by
	* writers it must reach value greater or equal to 0 (multiple writers
	* model). */
	psSD->uiRefCount--;

	if (psSD == psNodeToRemove->psRDesc)
	{
	PVR_ASSERT(0 == psSD->uiRefCount);
	/* Remove stream descriptor (i.e. stream reader context) */
	psNodeToRemove->psRDesc = NULL;
	}
	else if (psSD == psNodeToRemove->psWDesc)
	{
	PVR_ASSERT(0 <= psSD->uiRefCount);

	psNodeToRemove->uiWRefCount--;

	/* Remove stream descriptor if reference == 0 */
	if (0 == psSD->uiRefCount)
	{
	psNodeToRemove->psWDesc = NULL;
	}
	}

	/* Do not Free Stream Node if there is a write reference (a producer
	* context) to the stream */
	if (NULL != psNodeToRemove->psRDesc \|\| NULL != psNodeToRemove->psWDesc \|\|
	0 != psNodeToRemove->uiWRefCount)
	{
	PVR_DPF_RETURN_VAL (IMG_FALSE);
	}

	/* Make stream pointer NULL to prevent it from being destroyed in
	* RemoveAndFreeStreamNode Cleanup of stream should be done by the calling
	* context */
	psNodeToRemove->psStream = NULL;
	RemoveAndFreeStreamNode(psNodeToRemove);

	PVR_DPF_RETURN_VAL (IMG_TRUE);
	}