[ARM] tegra: add nvos/nvrm/nvmap drivers

arch/arm/mach-tegra/nv/nvos/nvos.c

+/*
+ * Copyright (c) 2008-2009 NVIDIA Corporation.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * Redistributions of source code must retain the above copyright notice,
+ * this list of conditions and the following disclaimer.
+ *
+ * Redistributions in binary form must reproduce the above copyright notice,
+ * this list of conditions and the following disclaimer in the documentation
+ * and/or other materials provided with the distribution.
+ *
+ * Neither the name of the NVIDIA Corporation nor the names of its contributors
+ * may be used to endorse or promote products derived from this software
+ * without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ *
+ */
+
+#include "nvos.h"
+#include "nvos_trace.h"
+#include "nvutil.h"
+#include "nverror.h"
+#include "nvassert.h"
+#include "nvbootargs.h"
+#include "nvio.h"
+#include <linux/delay.h>
+#include <linux/interrupt.h>
+#include <linux/irq.h>
+#include <linux/jiffies.h>
+#include <linux/time.h>
+#include <linux/kernel.h>
+#include <linux/kthread.h>
+#include <linux/mm.h>
+#include <linux/mutex.h>
+#include <linux/sched.h>
+#include <linux/semaphore.h>
+#include <linux/spinlock.h>
+#include <linux/string.h>
+#include <linux/uaccess.h>
+#include <linux/vmalloc.h>
+#include <linux/pagemap.h>
+#include <linux/dma-mapping.h>
+#include <asm/atomic.h>
+#include <asm/io.h>
+#include <asm/page.h>
+#include <asm/div64.h>
+#include <asm/setup.h>
+#include <asm/cacheflush.h>
+#include <mach/irqs.h>
+#include <linux/freezer.h>
+#include <linux/slab.h>
+
+#if NVOS_TRACE || NV_DEBUG
+#undef NvOsAlloc
+#undef NvOsFree
+#undef NvOsRealloc
+#undef NvOsSharedMemAlloc
+#undef NvOsSharedMemMap
+#undef NvOsSharedMemUnmap
+#undef NvOsSharedMemFree
+#undef NvOsMutexCreate
+#undef NvOsExecAlloc
+#undef NvOsExecFree
+#undef NvOsPageAlloc
+#undef NvOsPageLock
+#undef NvOsPageFree
+#undef NvOsPageMap
+#undef NvOsPageMapIntoPtr
+#undef NvOsPageUnmap
+#undef NvOsPageAddress
+#undef NvOsIntrMutexCreate
+#undef NvOsIntrMutexLock
+#undef NvOsIntrMutexUnlock
+#undef NvOsIntrMutexDestroy
+#undef NvOsInterruptRegister
+#undef NvOsInterruptUnregister
+#undef NvOsInterruptEnable
+#undef NvOsInterruptDone
+#undef NvOsPhysicalMemMapIntoCaller
+#undef NvOsMutexLock
+#undef NvOsMutexUnlock
+#undef NvOsMutexDestroy
+#undef NvOsPhysicalMemMap
+#undef NvOsPhysicalMemUnmap
+#undef NvOsSemaphoreCreate
+#undef NvOsSemaphoreWait
+#undef NvOsSemaphoreWaitTimeout
+#undef NvOsSemaphoreSignal
+#undef NvOsSemaphoreDestroy
+#undef NvOsSemaphoreClone
+#undef NvOsSemaphoreUnmarshal
+#undef NvOsThreadCreate
+#undef NvOsInterruptPriorityThreadCreate
+#undef NvOsThreadJoin
+#undef NvOsThreadYield
+#endif
+
+#define KTHREAD_IRQ_PRIO (MAX_RT_PRIO>>1)
+
+#define NVOS_MAX_SYSTEM_IRQS NR_IRQS
+
+#define NVOS_IRQ_IS_ENABLED 0x1
+
+/* NVOS_IRQ_IS_ flags are mutually exclusive.
+ * IS_TASKLET executes the handler in a tasklet (used for kernel drivers)
+ * IS_KERNEL_THREAD executes in a kernel thread (used for kernel GPIOs)
+ * IS_USER simply signals an NvOs semaphore (used for user-mode interrupts)
+ *
+ * Currently the choice is based on the IRQ number and if the requester is
+ * an IOCTL. Later this can be modified to be exposed in the public APIs.
+ *
+ * If no flag is set, the IRQ is handled in the interrupt handler itself.
+ */
+
+#define NVOS_IRQ_TYPE_SHIFT 1
+#define NVOS_IRQ_TYPE_MASK (0x3 << NVOS_IRQ_TYPE_SHIFT)
+
+#define NVOS_IRQ_IS_IRQ           (0)
+#define NVOS_IRQ_IS_TASKLET       (0x1 << NVOS_IRQ_TYPE_SHIFT)
+#define NVOS_IRQ_IS_KERNEL_THREAD (0x2 << NVOS_IRQ_TYPE_SHIFT)
+#define NVOS_IRQ_IS_USER          (0x3 << NVOS_IRQ_TYPE_SHIFT)
+
+static DEFINE_SPINLOCK(gs_NvOsSpinLock);
+
+typedef struct NvOsIrqHandlerRec
+{
+    union
+    {
+        NvOsInterruptHandler  pHandler;
+        NvOsSemaphoreHandle   pSem;
+    };
+    NvU32                 Irq;
+    char                  IrqName[16];
+    struct semaphore      sem;
+    struct task_struct    *task;
+    struct tasklet_struct Tasklet;
+} NvOsIrqHandler;
+
+typedef struct NvOsInterruptBlockRec
+{
+    void                *pArg;
+    NvU32               Flags;
+    NvU32               NumIrqs;
+    NvU32               Shutdown;
+    NvOsIrqHandler      IrqList[1];
+} NvOsInterruptBlock;
+
+#define INTBLOCK_SIZE(NUMIRQS) \
+    (sizeof(NvOsInterruptBlock) + ((NUMIRQS)-1)*sizeof(NvOsIrqHandler))
+
+static NvOsInterruptBlock *s_pIrqList[NVOS_MAX_SYSTEM_IRQS] = { NULL };
+
+static NvBootArgs s_BootArgs = { {0}, {0}, {0}, {0}, {0}, {0}, {{0}} };
+
+/*  The tasklet "data" parameter is a munging of the s_pIrqList index
+ *  (just the IRQ number), and the InterruptBlock's IrqList index, to
+ *  make interrupt handler lookups O(n)
+ */
+static void NvOsTaskletWrapper(
+       unsigned long data)
+{
+    NvOsInterruptBlock *pBlock = s_pIrqList[(data&0xffff)];
+    if (pBlock)
+        (*pBlock->IrqList[data>>16].pHandler)(pBlock->pArg);    
+}
+
+/*  The thread "pdata" parameter is a munging of the s_pIrqList index
+ *  (just the IRQ number), and the InterruptBlock's IrqList index, to
+ *  make interrupt handler lookups O(n)
+ */
+static int NvOsInterruptThreadWrapper(
+     void *pdata)
+{
+    unsigned long data = (unsigned long)pdata;
+    NvOsInterruptBlock *pBlock = s_pIrqList[(data&0xffff)];
+
+    if (!pBlock)
+    {
+        return 0;
+    } 
+    while (!pBlock->Shutdown)
+    {
+        int t;
+
+        /* Is the timeout large enough? */
+        t = down_interruptible(&pBlock->IrqList[data>>16].sem);
+
+        if (pBlock->Shutdown)
+            break;
+
+        if (t)
+            continue;
+
+        (*pBlock->IrqList[data>>16].pHandler)(pBlock->pArg);
+    }
+
+    return 0;
+}
+
+static irqreturn_t NvOsIrqWrapper(
+    int irq,
+    void *dev_id)
+{
+    unsigned long data = (unsigned long)dev_id;
+    NvOsInterruptBlock *pBlock = s_pIrqList[irq];
+
+    disable_irq_nosync(irq);
+    switch (pBlock->Flags & NVOS_IRQ_TYPE_MASK)
+    {
+    case NVOS_IRQ_IS_TASKLET:
+        tasklet_schedule(&pBlock->IrqList[data].Tasklet);
+        break;
+    case NVOS_IRQ_IS_KERNEL_THREAD:
+        up(&(pBlock->IrqList[data].sem));
+        break;
+    case NVOS_IRQ_IS_USER:
+        NvOsSemaphoreSignal(pBlock->IrqList[data].pSem);
+        break;
+    case NVOS_IRQ_IS_IRQ:
+        (*pBlock->IrqList[data].pHandler)(pBlock->pArg);
+        break;
+    }
+
+    return IRQ_HANDLED;
+}
+
+NvError NvOsFprintf(NvOsFileHandle stream, const char *format, ...)
+{
+    return NvError_NotImplemented;
+}
+
+NvS32 NvOsSnprintf(char *str, size_t size, const char *format, ...)
+{
+    va_list ap;
+    va_start( ap, format );
+    return vsnprintf( str, size, format, ap );
+    va_end( ap );
+}
+
+NvError NvOsVfprintf(NvOsFileHandle stream, const char *format, va_list ap)
+{
+    return NvError_NotImplemented;
+}
+
+NvS32 NvOsVsnprintf(char *str, size_t size, const char *format, va_list ap)
+{
+    return vsnprintf( str, size, format, ap );
+}
+
+void NvOsDebugPrintf(const char *format, ...)
+{
+    va_list ap;
+    va_start( ap, format );
+    vprintk( format, ap );
+    va_end( ap );
+}
+
+void
+NvOsDebugVprintf( const char *format, va_list ap )
+{
+    vprintk( format, ap );
+}
+
+NvS32 NvOsDebugNprintf(const char *format, ...)
+{
+    NvS32 r;
+    va_list ap;
+    va_start( ap, format );
+    r = vprintk( format, ap );
+    va_end( ap );
+    return r;
+}
+
+
+NvError NvOsGetOsInformation(NvOsOsInfo *pOsInfo)
+{
+    if (pOsInfo)
+    {
+        NvOsMemset(pOsInfo, 0, sizeof(NvOsOsInfo));
+        pOsInfo->OsType = NvOsOs_Linux;
+    }
+    else
+    {
+        return NvError_BadParameter;
+    }
+    return NvError_Success;
+}
+
+void NvOsStrncpy(char *dest, const char *src, size_t size)
+{
+    strncpy( dest, src, size );
+}
+
+NvOsCodePage NvOsStrGetSystemCodePage(void)
+{
+    return (NvOsCodePage)0;
+}
+
+size_t NvOsStrlen(const char *s)
+{
+    return strlen(s);
+}
+
+int NvOsStrcmp(const char *s1, const char *s2)
+{
+    return strcmp(s1, s2);
+}
+
+int NvOsStrncmp(const char *s1, const char *s2, size_t size)
+{
+    return strncmp(s1, s2, size);
+}
+
+void NvOsMemcpy(void *dest, const void *src, size_t size)
+{
+    memcpy(dest, src, size);
+}
+
+int NvOsMemcmp(const void *s1, const void *s2, size_t size)
+{
+    return memcmp(s1, s2, size);
+}
+
+void NvOsMemset(void *s, NvU8 c, size_t size)
+{
+    memset(s, c, size);
+}
+
+void NvOsMemmove(void *dest, const void *src, size_t size)
+{
+    memmove(dest, src, size);
+}
+
+NvError NvOsCopyIn(void *pDst, const void *pSrc, size_t Bytes)
+{
+    if (!Bytes)
+        return NvSuccess;
+
+    if( access_ok( VERIFY_READ, pSrc, Bytes ) )
+    {
+        __copy_from_user(pDst, pSrc, Bytes);
+        return NvSuccess;
+    }
+
+    return NvError_InvalidAddress;
+}
+
+NvError NvOsCopyOut(void *pDst, const void *pSrc, size_t Bytes)
+{
+    if (!Bytes)
+        return NvSuccess;
+
+    if( access_ok( VERIFY_WRITE, pDst, Bytes ) )
+    {
+        __copy_to_user(pDst, pSrc, Bytes);
+        return NvSuccess;
+    }
+
+    return NvError_InvalidAddress;
+}
+
+NvError NvOsFopen(const char *path, NvU32 flags, NvOsFileHandle *file)
+{
+    return NvError_NotImplemented;
+}
+
+void NvOsFclose(NvOsFileHandle stream)
+{
+}
+
+NvError NvOsFwrite(NvOsFileHandle stream, const void *ptr, size_t size)
+{
+    return NvError_NotImplemented;
+}
+
+NvError NvOsFread(
+    NvOsFileHandle stream,
+    void *ptr,
+    size_t size,
+    size_t *bytes)
+{
+    return NvError_NotImplemented;
+}
+
+NvError NvOsFreadTimeout(
+    NvOsFileHandle stream,
+    void *ptr,
+    size_t size,
+    size_t *bytes,
+    NvU32 timeout_msec)
+{
+    return NvError_NotImplemented;
+}
+
+NvError NvOsFgetc(NvOsFileHandle stream, NvU8 *c)
+{
+    return NvError_NotImplemented;
+}
+
+NvError NvOsFseek(NvOsFileHandle file, NvS64 offset, NvOsSeekEnum whence)
+{
+    return NvError_NotImplemented;
+}
+
+NvError NvOsFtell(NvOsFileHandle file, NvU64 *position)
+{
+    return NvError_NotImplemented;
+}
+
+NvError NvOsStat(const char *filename, NvOsStatType *stat)
+{
+    return NvError_NotImplemented;
+}
+
+NvError NvOsFstat(NvOsFileHandle file, NvOsStatType *stat)
+{
+    return NvError_NotImplemented;
+}
+
+NvError NvOsFflush(NvOsFileHandle stream)
+{
+    return NvError_NotImplemented;
+}
+
+NvError NvOsFsync(NvOsFileHandle stream)
+{
+    return NvError_NotImplemented;
+}
+
+NvError NvOsIoctl(
+    NvOsFileHandle hFile,
+    NvU32 IoctlCode,
+    void *pBuffer,
+    NvU32 InBufferSize,
+    NvU32 InOutBufferSize,
+    NvU32 OutBufferSize)
+{
+    return NvError_NotImplemented;
+}
+
+NvError NvOsOpendir(const char *path, NvOsDirHandle *dir)
+{
+    return NvError_NotImplemented;
+}
+
+NvError NvOsReaddir(NvOsDirHandle dir, char *name, size_t size)
+{
+    return NvError_NotImplemented;
+}
+
+void NvOsClosedir(NvOsDirHandle dir)
+{
+}
+
+const NvOsFileHooks *NvOsSetFileHooks(NvOsFileHooks *newHooks)
+{
+    return 0;
+}
+
+NvError NvOsGetConfigU32(const char *name, NvU32 *value)
+{
+    return NvError_NotImplemented;
+}
+
+NvError NvOsGetConfigString(const char *name, char *value, NvU32 size)
+{
+    return NvError_NotImplemented;
+}
+
+void *NvOsAlloc(size_t size)
+{
+    size_t AllocSize = size + sizeof(size_t);
+    size_t* ptr = NULL;
+    ptr = vmalloc(AllocSize);
+    if (!ptr)
+        return ptr;
+    *ptr = size;
+    ptr++;
+    return (ptr);
+}
+
+void *NvOsRealloc(void *ptr, size_t size)
+{
+    size_t* NewPtr = NULL;
+    size_t OldSize = 0;
+    size_t SmallerSize = 0;
+
+    if( !ptr )
+    {
+        return NvOsAlloc(size);
+    }
+    if (!size)
+    {
+        NvOsFree(ptr);
+        return NULL;
+    }
+
+    // Get the size of the memory allocated for ptr.
+    NewPtr = (size_t*)ptr;
+    NewPtr--;
+    OldSize = *NewPtr;
+    if (size == OldSize)
+        return ptr;
+    SmallerSize = (OldSize > size) ? size : OldSize;
+
+    NewPtr = NvOsAlloc(size);
+    if(!NewPtr)
+        return NULL;
+    NvOsMemcpy(NewPtr, ptr, SmallerSize);
+    NvOsFree(ptr);
+    return NewPtr;
+}
+
+void NvOsFree(void *ptr)
+{
+    size_t* AllocPtr = NULL;
+    if (ptr)
+    {
+        AllocPtr = (size_t*)ptr;
+        AllocPtr--;
+    }
+    else
+        return;
+    vfree(AllocPtr);
+}
+
+void *NvOsExecAlloc(size_t size)
+{
+    return vmalloc_exec( size );
+}
+
+NvError NvOsSharedMemAlloc(
+    const char *key,
+    size_t size,
+    NvOsSharedMemHandle *descriptor)
+{
+    return NvError_NotImplemented;
+}
+
+NvError NvOsSharedMemMap(
+    NvOsSharedMemHandle descriptor,
+    size_t offset,
+    size_t size,
+    void **ptr)
+{
+    return NvError_NotImplemented;
+}
+
+
+void NvOsSharedMemUnmap(void *ptr, size_t size)
+{
+}
+
+void NvOsSharedMemFree(NvOsSharedMemHandle descriptor)
+{
+}    
+
+NvError NvOsPhysicalMemMap(
+    NvOsPhysAddr phys,
+    size_t size,
+    NvOsMemAttribute attrib,
+    NvU32 flags,
+    void **ptr)
+{
+    /*  For apertures in the static kernel mapping, just return the
+     *  static VA rather than creating a new mapping 
+     *  FIXME:  Eventually, the static phyiscal apertures should be
+     *  registered with NvOs when mapped, since they could be
+     *  chip-dependent
+     */
+#define aperture_comp_map(_name, _pa, _len)                             \
+    if ((phys >= (NvOsPhysAddr)(_pa)) &&                                \
+        ((NvOsPhysAddr)(phys+size)<=(NvOsPhysAddr)((_pa)+(_len)))) {    \
+            *ptr = (void *)tegra_munge_pa(phys);                        \
+            return NvSuccess;                                           \
+    }
+
+    tegra_apertures(aperture_comp_map);
+
+    if (attrib == NvOsMemAttribute_WriteCombined)
+    {
+        *ptr = ioremap_wc(phys, size);
+    }
+    else if (attrib == NvOsMemAttribute_WriteBack)
+    {
+        *ptr = ioremap_cached(phys, size);
+    }
+    else
+    {
+        *ptr = ioremap_nocache(phys, size);
+    }
+
+    if (*ptr == 0)
+        return NvError_InsufficientMemory;
+
+    return NvSuccess;
+}
+
+NvError NvOsPhysicalMemMapIntoCaller(
+    void *pCallerPtr,
+    NvOsPhysAddr phys,
+    size_t size,
+    NvOsMemAttribute attrib,
+    NvU32 flags)
+{
+    return NvError_NotImplemented;
+}
+
+void NvOsPhysicalMemUnmap(void *ptr, size_t size)
+{
+    NvUPtr va = (NvUPtr)ptr;
+
+    /*  No unmapping required for statically mapped I/O space */
+#define aperture_comp_unmap(_name, _pa, _len)                           \
+    if ((tegra_munge_pa((_pa)) <= va) &&                                \
+        (tegra_munge_pa((_pa))+(_len) >= (va+size)))                    \
+        return;
+
+
+    tegra_apertures(aperture_comp_unmap);
+    iounmap(ptr);
+}
+
+NvError NvOsLibraryLoad(const char *name, NvOsLibraryHandle *library)
+{
+    return NvError_NotImplemented;
+}
+
+void* NvOsLibraryGetSymbol(NvOsLibraryHandle library, const char *symbol)
+{
+    return 0;
+}
+
+void NvOsLibraryUnload(NvOsLibraryHandle library)
+{
+}
+
+void NvOsSleepMS(NvU32 msec)
+{
+    msleep( msec );
+}
+
+void NvOsWaitUS(NvU32 usec)
+{
+    udelay( usec );
+}
+
+typedef struct NvOsMutexRec
+{
+    struct mutex mutex;
+    volatile NvU32 count;
+    volatile struct thread_info *owner;
+} NvOsMutex;
+
+/**
+ * nvos mutexes are recursive.
+ */
+NvError NvOsMutexCreate(NvOsMutexHandle *mutex)
+{
+    NvOsMutex *m;
+
+    m = kzalloc( sizeof(NvOsMutex), GFP_KERNEL );
+    if( !m )
+        return NvError_InsufficientMemory;
+
+    mutex_init( &m->mutex );
+    m->count = 0;
+    m->owner = 0;
+
+    *mutex = m;
+    return NvSuccess;
+}
+
+void NvOsMutexLock(NvOsMutexHandle mutex)
+{
+    struct task_struct *task = current;
+    struct thread_info *info = task_thread_info(task);
+    int ret;
+
+    NV_ASSERT( mutex );
+
+    /* if we own the lock, increment the count and bail out */
+    if( mutex->owner == info )
+    {
+        mutex->count++;
+        return;
+    }
+
+    /* lock as normal, then setup the recursive stuff */
+    do
+    {
+        /*  FIXME: interruptible mutexes may not be necessary, since this
+         *  implementation is only used by the kernel tasks. */
+        ret = mutex_lock_interruptible( &mutex->mutex );
+        //  If a signal arrives while the task is sleeping,
+        //  re-schedule it and attempt to reacquire the mutex
+        if (ret && !try_to_freeze())
+            schedule();
+    } while (ret);
+    mutex->owner = info;
+    mutex->count = 1;
+}
+
+void NvOsMutexUnlock(NvOsMutexHandle mutex)
+{
+    NV_ASSERT( mutex );
+
+    mutex->count--;
+    if( mutex->count == 0 )
+    {
+        /* prevent the same thread from unlocking, then doing a recursive
+         * lock (skip mutex_lock).
+         */
+        mutex->owner = 0;
+
+        mutex_unlock( &mutex->mutex );
+    }
+}
+
+void NvOsMutexDestroy(NvOsMutexHandle mutex)
+{
+
+    if( !mutex )
+        return;
+    kfree( mutex );
+}
+
+typedef struct NvOsIntrMutexRec
+{
+    spinlock_t lock;
+    unsigned long flags;
+} NvOsIntrMutex;
+
+NvError NvOsIntrMutexCreate(NvOsIntrMutexHandle *mutex)
+{
+    NvOsIntrMutex *m;
+
+    m = kzalloc( sizeof(NvOsIntrMutex), GFP_KERNEL );
+    if( !m )
+        return NvError_InsufficientMemory;
+
+    spin_lock_init( &m->lock );
+    *mutex = m;
+    return NvSuccess;
+}
+
+void NvOsIntrMutexLock(NvOsIntrMutexHandle mutex)
+{
+    NV_ASSERT( mutex );
+    spin_lock_irqsave( &mutex->lock, mutex->flags );
+}
+
+void NvOsIntrMutexUnlock(NvOsIntrMutexHandle mutex)
+{
+    NV_ASSERT( mutex );
+    spin_unlock_irqrestore( &mutex->lock, mutex->flags );
+}
+
+void NvOsIntrMutexDestroy(NvOsIntrMutexHandle mutex)
+{
+    if (mutex)
+        kfree(mutex);
+}
+
+typedef struct NvOsSpinMutexRec
+{
+    spinlock_t lock;
+} NvOsSpinMutex;
+
+NvError NvOsSpinMutexCreate(NvOsSpinMutexHandle *mutex)
+{
+    NvOsSpinMutex *m;
+
+    m = kzalloc( sizeof(NvOsSpinMutex), GFP_KERNEL );
+    if( !m )
+        return NvError_InsufficientMemory;
+
+    spin_lock_init( &m->lock );
+    *mutex = m;
+    return NvSuccess;
+}
+
+void NvOsSpinMutexLock(NvOsSpinMutexHandle mutex)
+{
+    NV_ASSERT( mutex );
+    spin_lock( &mutex->lock );
+}
+
+void NvOsSpinMutexUnlock(NvOsSpinMutexHandle mutex)
+{
+    NV_ASSERT( mutex );
+    spin_unlock( &mutex->lock );
+}
+
+void NvOsSpinMutexDestroy(NvOsSpinMutexHandle mutex)
+{
+    if (mutex)
+        kfree(mutex);
+}
+
+typedef struct NvOsSemaphoreRec
+{
+    struct semaphore sem;
+    atomic_t refcount;
+} NvOsSemaphore;
+
+NvError NvOsSemaphoreCreate(
+    NvOsSemaphoreHandle *semaphore,
+    NvU32 value)
+{
+    NvOsSemaphore *s;
+
+    s = kzalloc( sizeof(NvOsSemaphore), GFP_KERNEL );
+    if( !s )
+        return NvError_InsufficientMemory;
+
+    sema_init( &s->sem, value );
+    atomic_set( &s->refcount, 1 );
+
+    *semaphore = s;
+
+    return NvSuccess;
+}
+
+NvError NvOsSemaphoreClone(
+    NvOsSemaphoreHandle orig,
+    NvOsSemaphoreHandle *semaphore)
+{
+    NV_ASSERT( orig );
+    NV_ASSERT( semaphore );
+
+    atomic_inc( &orig->refcount );
+    *semaphore = orig;
+
+    return NvSuccess;
+}
+
+NvError NvOsSemaphoreUnmarshal(
+    NvOsSemaphoreHandle hClientSema,
+    NvOsSemaphoreHandle *phDriverSema)
+{
+    NV_ASSERT( hClientSema );
+    NV_ASSERT( phDriverSema );
+
+    atomic_inc( &hClientSema->refcount );
+    *phDriverSema = hClientSema;
+
+    return NvSuccess;
+}
+
+int NvOsSemaphoreWaitInterruptible(NvOsSemaphoreHandle semaphore);
+int NvOsSemaphoreWaitInterruptible(NvOsSemaphoreHandle semaphore)
+{
+    NV_ASSERT(semaphore);
+
+    return down_interruptible(&semaphore->sem);
+}
+
+void NvOsSemaphoreWait(NvOsSemaphoreHandle semaphore)
+{
+    int ret;
+    
+    NV_ASSERT(semaphore);
+
+    do
+    {
+        /* FIXME: We should split the implementation into two parts -
+         * one for semaphore that were created by users ioctl'ing into
+         * the nvos device (which need down_interruptible), and others that
+         * are created and used by the kernel drivers, which do not */
+        ret = down_interruptible(&semaphore->sem);
+        /* The kernel doesn't reschedule tasks
+         * that have pending signals. If a signal
+         * is pending, forcibly reschedule the task.
+         */
+        if (ret && !try_to_freeze())
+            schedule();
+    } while (ret);
+}
+
+NvError NvOsSemaphoreWaitTimeout(
+    NvOsSemaphoreHandle semaphore,
+    NvU32 msec)
+{
+    int t;
+
+    NV_ASSERT( semaphore );
+
+    if (!semaphore)
+        return NvError_Timeout;
+
+    if (msec==NV_WAIT_INFINITE)
+    {
+        NvOsSemaphoreWait(semaphore);
+        return NvSuccess;
+    }
+    else if (msec==0)
+    {
+        t = down_trylock(&semaphore->sem);
+        if (!t)
+            return NvSuccess;
+        else
+            return NvError_Timeout;
+    }
+
+    /* FIXME:  The kernel doesn't provide an interruptible timed
+     * semaphore wait, which would be preferable for our the ioctl'd
+     * NvOs sempahores. */
+    t = down_timeout(&semaphore->sem, (long)msecs_to_jiffies( msec ));
+
+    if (t == -ETIME)
+        return NvError_Timeout;
+    else if (!t)
+        return NvSuccess;
+
+    return NvError_AccessDenied;
+}
+
+void NvOsSemaphoreSignal(NvOsSemaphoreHandle semaphore)
+{
+    NV_ASSERT( semaphore );
+
+    up( &semaphore->sem );
+}
+
+void NvOsSemaphoreDestroy(NvOsSemaphoreHandle semaphore)
+{
+    if (!semaphore)
+        return;
+
+    if( atomic_dec_return( &semaphore->refcount ) == 0 )
+        kfree( semaphore );
+}
+
+NvError NvOsThreadMode(int coop)
+{
+    return NvError_NotImplemented;
+}
+
+typedef struct NvOsThreadRec
+{
+    struct task_struct *task;
+    NvOsThreadFunction func;
+    void *arg;
+} NvOsThread;
+
+static int thread_wrapper( void *arg )
+{
+    NvOsThread *t = (NvOsThread *)arg;
+    t->func(t->arg);
+    return 0;
+}
+
+static NvError NvOsThreadCreateInternal(
+    NvOsThreadFunction function,
+    void *args,
+    NvOsThreadHandle *thread,
+    NvBool elevatedPriority)
+{
+    NvError e;
+    NvOsThread *t = 0;
+    static NvU32 NvOsKernelThreadIndex = 0;
+    struct sched_param sched;
+    int scheduler;
+    NvU32 ThreadId;
+
+    t = kzalloc( sizeof(NvOsThread), GFP_KERNEL );
+    if( !t )
+    {
+        return NvError_InsufficientMemory;
+    }
+
+    t->func = function;
+    t->arg = args;
+
+    ThreadId = (NvU32)NvOsAtomicExchangeAdd32((NvS32*)&NvOsKernelThreadIndex,1);
+    t->task =
+        kthread_create(thread_wrapper, t, "NvOsKernelThread/%d", ThreadId);
+
+    if(IS_ERR(t->task))
+    {
+        e = NvError_InsufficientMemory;
+        goto fail;
+    }
+
+    if (elevatedPriority)
+    {
+        scheduler = SCHED_FIFO;
+        sched.sched_priority = KTHREAD_IRQ_PRIO+1;
+    }
+    else
+    {
+        scheduler = SCHED_NORMAL;
+        sched.sched_priority = 0;
+    }
+
+    if (sched_setscheduler_nocheck( t->task, scheduler, &sched ) < 0)
+        NvOsDebugPrintf("Failed to set task priority to %d\n",
+            sched.sched_priority);
+    
+    *thread = t;
+    wake_up_process( t->task );
+    e = NvSuccess;
+    goto clean;
+
+fail:
+    kfree( t );
+
+clean:
+    return e;
+}
+
+
+NvError NvOsInterruptPriorityThreadCreate(
+    NvOsThreadFunction function,
+    void *args,
+    NvOsThreadHandle *thread)
+{
+    return NvOsThreadCreateInternal(function, args, thread, NV_TRUE);
+}
+
+NvError NvOsThreadCreate(
+    NvOsThreadFunction function,
+    void *args,
+    NvOsThreadHandle *thread)
+{
+    return NvOsThreadCreateInternal(function, args, thread, NV_FALSE);
+}
+
+NvError NvOsThreadSetLowPriority(void)
+{
+    struct sched_param sched;
+    struct task_struct *curr;
+
+    curr = get_current();
+    sched.sched_priority = 0;
+
+    if (unlikely(!curr))
+        return NvError_NotInitialized;
+
+    if (sched_setscheduler_nocheck( curr, SCHED_IDLE, &sched )<0)
+    {
+        NvOsDebugPrintf("Failed to set low priority for thread %p\n", curr);
+        return NvError_NotSupported;
+    }
+
+    return NvSuccess;
+}
+
+void NvOsThreadJoin(NvOsThreadHandle thread)
+{
+    if (!thread)
+        return;
+
+    (void)kthread_stop(thread->task);
+    kfree(thread);
+}
+
+void NvOsThreadYield(void)
+{
+    schedule();
+}
+
+NvS32 NvOsAtomicCompareExchange32(
+    NvS32 *pTarget,
+    NvS32 OldValue,
+    NvS32 NewValue)
+{
+    return atomic_cmpxchg( (atomic_t *)pTarget, OldValue, NewValue );
+}
+
+NvS32 NvOsAtomicExchange32(NvS32 *pTarget, NvS32 Value)
+{
+    return atomic_xchg( (atomic_t *)pTarget, Value );
+}
+
+NvS32 NvOsAtomicExchangeAdd32(NvS32 *pTarget, NvS32 Value)
+{
+    NvS32 new;
+    new = atomic_add_return( Value, (atomic_t *)pTarget );
+    return new + (-Value);
+}
+
+NvU32 NvOsTlsAlloc(void)
+{
+    return 0;
+}
+
+void NvOsTlsFree(NvU32 TlsIndex)
+{
+}
+
+void *NvOsTlsGet(NvU32 TlsIndex)
+{
+    return 0;
+}
+
+void NvOsTlsSet(NvU32 TlsIndex, void *Value)
+{
+}
+
+NvU32 NvOsGetTimeMS(void)
+{
+    struct timespec ts;
+    s64 nsec;
+    getnstimeofday(&ts);
+    nsec = timespec_to_ns(&ts);
+    do_div(nsec, 1000000);
+    return (NvU32)nsec;
+}
+
+NvU64 NvOsGetTimeUS(void)
+{
+    struct timespec ts;
+    s64 nsec;
+    getnstimeofday(&ts);
+    nsec = timespec_to_ns(&ts);
+    do_div(nsec, 1000);
+    return (NvU32)nsec;
+}
+
+void NvOsDataCacheWritebackRange(
+    void *start,
+    NvU32 length)
+{
+        dmac_map_area(start, length, DMA_TO_DEVICE);
+}
+
+void NvOsDataCacheWritebackInvalidateRange(
+    void *start,
+    NvU32 length)
+{
+    dmac_flush_range(start, (NvU8*)start+length);
+}
+
+void NvOsInstrCacheInvalidate(void)
+{
+}
+
+void NvOsInstrCacheInvalidateRange(
+    void *start,
+    NvU32 length)
+{
+    __cpuc_coherent_kern_range((unsigned long)start,
+         (unsigned long)start+length);
+}
+
+void NvOsFlushWriteCombineBuffer( void )
+{
+    dsb();
+    outer_sync();
+}
+
+NvError NvOsInterruptRegisterInternal(
+    NvU32 IrqListSize,
+    const NvU32 *pIrqList,
+    const void *pList,
+    void* context,
+    NvOsInterruptHandle *handle,
+    NvBool InterruptEnable,
+    NvBool IsUser)
+{
+    const NvOsSemaphoreHandle *pSemList = NULL;
+    const NvOsInterruptHandler *pFnList = NULL;
+    NvError e = NvSuccess;
+    NvOsInterruptBlock *pNewBlock;
+    NvU32 i;
+
+    if (!IrqListSize)
+        return NvError_BadValue;
+
+    if (IsUser)
+        pSemList = (const NvOsSemaphoreHandle *)pList;
+    else
+        pFnList = (const NvOsInterruptHandler *)pList;
+
+    *handle = (NvOsInterruptHandle) 0;
+    pNewBlock = (NvOsInterruptBlock *)NvOsAlloc(INTBLOCK_SIZE(IrqListSize));
+    if (!pNewBlock)
+        return NvError_InsufficientMemory;
+
+    NvOsMemset(pNewBlock, 0, INTBLOCK_SIZE(IrqListSize));
+
+    pNewBlock->pArg = context;
+    pNewBlock->NumIrqs = IrqListSize;
+    pNewBlock->Shutdown = 0;
+    for (i=0; i<IrqListSize; i++)
+    {
+        if (pIrqList[i] >= NVOS_MAX_SYSTEM_IRQS)
+        {
+            BUG();
+            e = NvError_InsufficientMemory;
+            goto clean_fail;
+        }
+
+        if (NvOsAtomicCompareExchange32((NvS32*)&s_pIrqList[pIrqList[i]], 0,
+                (NvS32)pNewBlock)!=0)
+        {
+            e = NvError_AlreadyAllocated;
+            goto clean_fail;
+        }
+        snprintf(pNewBlock->IrqList[i].IrqName, 
+            sizeof(pNewBlock->IrqList[i].IrqName),
+            "NvOsIrq%s%04d", (IsUser)?"User":"Kern", pIrqList[i]);
+
+        pNewBlock->IrqList[i].Irq = pIrqList[i];
+
+        /* HACK use threads for GPIO and tasklets for all other interrupts. */
+        if (IsUser)
+        {
+            pNewBlock->IrqList[i].pSem = pSemList[i];
+            pNewBlock->Flags |= NVOS_IRQ_IS_USER;
+        }
+        else
+        {
+            pNewBlock->IrqList[i].pHandler = pFnList[i];
+            if (pIrqList[i] >= INT_GPIO_BASE)
+                pNewBlock->Flags |= NVOS_IRQ_IS_KERNEL_THREAD;
+            else
+                pNewBlock->Flags |= NVOS_IRQ_IS_TASKLET;
+        }
+    
+        if ((pNewBlock->Flags & NVOS_IRQ_TYPE_MASK)==NVOS_IRQ_IS_KERNEL_THREAD)
+        {
+            struct sched_param p;
+            p.sched_priority = KTHREAD_IRQ_PRIO;
+            sema_init(&(pNewBlock->IrqList[i].sem), 0);
+            pNewBlock->IrqList[i].task = 
+                kthread_create(NvOsInterruptThreadWrapper,
+                    (void *)((pIrqList[i]&0xffff) | ((i&0xffff)<<16)), 
+                    pNewBlock->IrqList[i].IrqName);
+            if (sched_setscheduler(pNewBlock->IrqList[i].task,
+                    SCHED_FIFO, &p)<0)
+                NvOsDebugPrintf("Failed to elevate priority for IRQ %u\n",
+                    pIrqList[i]);
+            wake_up_process( pNewBlock->IrqList[i].task );
+        }
+
+        if ((pNewBlock->Flags & NVOS_IRQ_TYPE_MASK)==NVOS_IRQ_IS_TASKLET)
+        {
+            tasklet_init(&pNewBlock->IrqList[i].Tasklet, NvOsTaskletWrapper,
+                (pIrqList[i]&0xffff) | ((i&0xffff)<<16)); 
+        }
+
+        /* NvOs specifies that the interrupt handler is responsible for
+         * re-enabling the interrupt.  This is not the standard behavior
+         * for Linux IRQs, so only interrupts which are installed through
+         * NvOs will have the no-auto-enable flag specified
+         */
+        set_irq_flags(pIrqList[i], IRQF_VALID | IRQF_NOAUTOEN);
+
+        if (request_irq(pIrqList[i], NvOsIrqWrapper, 
+                0, pNewBlock->IrqList[i].IrqName, (void*)i)!=0)
+        {
+            e = NvError_ResourceError;
+            goto clean_fail;
+        }
+    }
+    *handle = (NvOsInterruptHandle)pNewBlock;
+    if (InterruptEnable)
+    {
+        pNewBlock->Flags |= NVOS_IRQ_IS_ENABLED;
+        i = 0;
+    }
+    for ( ; i<IrqListSize; i++)
+        enable_irq(pIrqList[i]);
+
+    return NvSuccess;
+
+ clean_fail:
+    while (i)
+    {
+        --i;
+        if ((pNewBlock->Flags & NVOS_IRQ_TYPE_MASK)==NVOS_IRQ_IS_KERNEL_THREAD)
+        {
+            up(&pNewBlock->IrqList[i].sem);
+            (void)kthread_stop(pNewBlock->IrqList[i].task);
+        }
+        if ((pNewBlock->Flags & NVOS_IRQ_TYPE_MASK) == NVOS_IRQ_IS_TASKLET)
+        {
+            tasklet_kill(&pNewBlock->IrqList[i].Tasklet); 
+        }
+        free_irq(pIrqList[i], (void*)i);
+        set_irq_flags(pIrqList[i], IRQF_VALID);
+        NvOsAtomicCompareExchange32((NvS32*)&s_pIrqList[pIrqList[i]],
+            (NvS32)pNewBlock, 0);
+    }
+    *handle = NULL;
+    NvOsFree(pNewBlock);
+
+    return e;
+}
+
+NvError NvOsInterruptRegister(
+    NvU32 IrqListSize,
+    const NvU32 *pIrqList,
+    const NvOsInterruptHandler *pIrqHandlerList,
+    void *context,
+    NvOsInterruptHandle *handle,
+    NvBool InterruptEnable)
+{
+    return NvOsInterruptRegisterInternal(IrqListSize, pIrqList,
+               (const void*)pIrqHandlerList, context, handle, 
+               InterruptEnable, NV_FALSE);
+}
+
+void NvOsInterruptUnregister(NvOsInterruptHandle handle)
+{
+    NvOsInterruptBlock *pBlock = (NvOsInterruptBlock *)handle;
+    NvU32 i;
+
+    if (!pBlock)
+        return;
+
+    pBlock->Shutdown = 1;
+
+    for (i=0; i<pBlock->NumIrqs; i++)
+    {
+        free_irq(pBlock->IrqList[i].Irq, (void*)i);
+        NvOsAtomicCompareExchange32(
+            (NvS32*)&s_pIrqList[pBlock->IrqList[i].Irq], (NvS32)pBlock, 0);
+
+        if ((pBlock->Flags & NVOS_IRQ_TYPE_MASK) == NVOS_IRQ_IS_KERNEL_THREAD)
+        {
+            up(&pBlock->IrqList[i].sem);
+            (void)kthread_stop(pBlock->IrqList[i].task);
+        }
+        if ((pBlock->Flags & NVOS_IRQ_TYPE_MASK) == NVOS_IRQ_IS_TASKLET)
+        {
+            tasklet_kill(&pBlock->IrqList[i].Tasklet); 
+        }
+        set_irq_flags(pBlock->IrqList[i].Irq, IRQF_VALID);
+    }
+
+    NvOsFree(pBlock);
+}
+
+NvError NvOsInterruptEnable(NvOsInterruptHandle handle)
+{
+    NvOsInterruptBlock *pBlock = (NvOsInterruptBlock *)handle;
+    NvU32 i;
+
+    if (pBlock == NULL)
+        BUG();
+
+    if (!(pBlock->Flags & NVOS_IRQ_IS_ENABLED))
+    {
+        pBlock->Flags |= NVOS_IRQ_IS_ENABLED;
+        for (i=0; i<pBlock->NumIrqs; i++)
+            enable_irq(pBlock->IrqList[i].Irq);
+    }
+
+    return NvSuccess;
+}
+
+void NvOsInterruptDone(NvOsInterruptHandle handle)
+{
+    NvOsInterruptBlock *pBlock = (NvOsInterruptBlock *)handle;
+    NvU32 i;
+
+    if (pBlock == NULL)
+        BUG();
+
+    for (i=0; i<pBlock->NumIrqs; i++)
+        enable_irq(pBlock->IrqList[i].Irq);
+}
+
+void NvOsInterruptMask(NvOsInterruptHandle handle, NvBool mask)
+{
+    NvOsInterruptBlock *pBlock = (NvOsInterruptBlock *)handle;
+    NvU32 i;
+
+    if (pBlock == NULL)
+        BUG();
+
+    if (mask)
+    {
+        for (i=0; i<pBlock->NumIrqs; i++)
+            disable_irq(pBlock->IrqList[i].Irq);
+    }
+    else
+    {
+        for (i=0; i<pBlock->NumIrqs; i++)
+            enable_irq(pBlock->IrqList[i].Irq);
+    }
+}
+
+void NvOsProfileApertureSizes(NvU32 *apertures, NvU32 *sizes)
+{
+}
+
+void NvOsProfileStart(void **apertures)
+{
+}
+
+void NvOsProfileStop(void **apertures)
+{
+}
+
+NvError NvOsProfileWrite(
+    NvOsFileHandle file, NvU32 index,
+    void *aperture)
+{
+    return NvError_NotImplemented;
+}
+
+NvError NvOsBootArgSet(NvU32 key, void *arg, NvU32 size)
+{
+    return NvError_NotImplemented;
+}
+
+NvError NvOsBootArgGet(NvU32 key, void *arg, NvU32 size)
+{
+    const void *src;
+    NvU32 size_src;
+
+    if (key>=NvBootArgKey_PreservedMemHandle_0 &&
+        key<NvBootArgKey_PreservedMemHandle_Num)
+    {
+        int Index = key - NvBootArgKey_PreservedMemHandle_0;
+
+        src = &s_BootArgs.MemHandleArgs[Index];
+        size_src = sizeof(NvBootArgsPreservedMemHandle);
+    }
+    else
+    {
+        switch (key)
+        {
+        case NvBootArgKey_ChipShmoo:
+            src = &s_BootArgs.ChipShmooArgs;
+            size_src = sizeof(NvBootArgsChipShmoo);
+            break;
+        case NvBootArgKey_Framebuffer:
+            src = &s_BootArgs.FramebufferArgs;
+            size_src = sizeof(NvBootArgsFramebuffer);
+            break;
+        case NvBootArgKey_Display:
+            src = &s_BootArgs.DisplayArgs;
+            size_src = sizeof(NvBootArgsDisplay);
+            break;
+        case NvBootArgKey_Rm:            
+            src = &s_BootArgs.RmArgs;
+            size_src = sizeof(NvBootArgsRm);
+            break;
+        case NvBootArgKey_ChipShmooPhys:
+            src = &s_BootArgs.ChipShmooPhysArgs;
+            size_src = sizeof(NvBootArgsChipShmooPhys);
+            break;
+        case NvBootArgKey_WarmBoot:
+            src = &s_BootArgs.WarmbootArgs;
+            size_src = sizeof(NvBootArgsWarmboot);
+            break;
+        default:
+            src = NULL;
+            size_src = 0;
+            break;
+        }
+    }
+
+    if (!arg || !src || (size_src!=size))
+        return NvError_BadParameter;
+
+    NvOsMemcpy(arg, src, size_src);
+    return NvSuccess;
+}
+
+/** nvassert functions */
+
+void NvOsBreakPoint(const char* file, NvU32 line, const char* condition)
+{
+    printk( "assert: %s:%d: %s\n", file, line, (condition) ? condition : " " );
+    dump_stack();
+}
+
+/** trace functions */
+
+void NvOsTraceLogPrintf( const char *format, ... )
+{
+
+}
+
+void NvOsTraceLogStart(void)
+{
+}
+
+void NvOsTraceLogEnd(void)
+{
+}
+
+/* resource tracking */
+
+#if NV_DEBUG
+void *NvOsAllocLeak( size_t size, const char *f, int l )
+{
+    return NvOsAlloc( size );
+}
+
+void *NvOsReallocLeak( void *ptr, size_t size, const char *f, int l )
+{
+    return NvOsRealloc( ptr, size );
+}
+
+void NvOsFreeLeak( void *ptr, const char *f, int l )
+{
+    NvOsFree( ptr );
+}
+#endif
+
+void NvOsGetProcessInfo(char* buf, NvU32 len)
+{
+        NvOsSnprintf(buf,len, "(kernel pid=%d)", current->pid);
+}
+
+#if (NVOS_TRACE || NV_DEBUG)
+void NvOsSetResourceAllocFileLine(void* userptr, const char* file, int line)
+{
+}
+#endif
+
+#ifdef GHACK
+
+static int __init parse_tegra_tag(const struct tag *tag)
+{
+    const struct tag_nvidia_tegra *nvtag = &tag->u.tegra;
+
+    if (nvtag->bootarg_key >= NvBootArgKey_PreservedMemHandle_0 &&
+        nvtag->bootarg_key < NvBootArgKey_PreservedMemHandle_Num)
+    {
+        int Index = nvtag->bootarg_key - NvBootArgKey_PreservedMemHandle_0;
+        NvBootArgsPreservedMemHandle *dst = &s_BootArgs.MemHandleArgs[Index];
+        const NvBootArgsPreservedMemHandle *src =
+            (const NvBootArgsPreservedMemHandle *)nvtag->bootarg;
+
+        if (nvtag->bootarg_len != sizeof(NvBootArgsPreservedMemHandle))
+            printk("Unexpected preserved memory handle tag length!\n");
+        else
+            *dst = *src;
+        return 0;
+    }
+
+    switch (nvtag->bootarg_key)
+    {
+    case NvBootArgKey_ChipShmoo:
+    {
+        NvBootArgsChipShmoo *dst = &s_BootArgs.ChipShmooArgs;
+        const NvBootArgsChipShmoo *src =
+            (const NvBootArgsChipShmoo *)nvtag->bootarg;
+
+        if (nvtag->bootarg_len != sizeof(NvBootArgsChipShmoo))
+            printk("Unexpected shmoo tag length!\n");
+        else
+        {
+            printk("Shmoo tag with %u handle\n",
+                   src->MemHandleKey);
+            *dst = *src;
+        }
+        return 0;
+    }
+    case NvBootArgKey_Display:
+    {
+        NvBootArgsDisplay *dst = &s_BootArgs.DisplayArgs;
+        const NvBootArgsDisplay *src =
+            (const NvBootArgsDisplay *)nvtag->bootarg;
+
+        if (nvtag->bootarg_len != sizeof(NvBootArgsDisplay))
+            printk("Unexpected display tag length!\n");
+        else
+            *dst = *src;
+        return 0;
+    }
+    case NvBootArgKey_Framebuffer:
+    {
+        NvBootArgsFramebuffer *dst = &s_BootArgs.FramebufferArgs;
+        const NvBootArgsFramebuffer *src =
+            (const NvBootArgsFramebuffer *)nvtag->bootarg;
+
+        if (nvtag->bootarg_len != sizeof(NvBootArgsFramebuffer))
+            printk("Unexpected framebuffer tag length!\n");
+        else
+        {
+            printk("Framebuffer tag with %u handle\n",
+                   src->MemHandleKey);
+            *dst = *src;
+        }
+        return 0;
+    }
+    case NvBootArgKey_Rm:
+    {
+        NvBootArgsRm *dst = &s_BootArgs.RmArgs;
+        const NvBootArgsRm *src =
+            (const NvBootArgsRm *)nvtag->bootarg;
+
+        if (nvtag->bootarg_len != sizeof(NvBootArgsRm))
+            printk("Unexpected RM tag length!\n");
+        else
+            *dst = *src;
+        return 0;
+    }
+    case NvBootArgKey_ChipShmooPhys:
+    {
+        NvBootArgsChipShmooPhys *dst = &s_BootArgs.ChipShmooPhysArgs;
+        const NvBootArgsChipShmooPhys *src =
+            (const NvBootArgsChipShmooPhys *)nvtag->bootarg;
+
+        if (nvtag->bootarg_len != sizeof(NvBootArgsChipShmooPhys))
+            printk("Unexpected phys shmoo tag length!\n");
+        else
+        {
+            printk("Phys shmoo tag with pointer 0x%X and length %u\n",
+                   src->PhysShmooPtr, src->Size);
+            *dst = *src;
+        }
+        return 0;
+    }
+    case NvBootArgKey_WarmBoot:
+    {
+        NvBootArgsWarmboot *dst = &s_BootArgs.WarmbootArgs;
+        const NvBootArgsWarmboot *src =
+            (const NvBootArgsWarmboot *)nvtag->bootarg;
+
+        if (nvtag->bootarg_len != sizeof(NvBootArgsWarmboot))
+            printk("Unexpected warmboot tag length!\n");
+        else
+        {
+            printk("Found a warmboot tag!\n");
+            *dst = *src;
+        }
+        return 0;
+    }
+
+    default:
+        return 0;
+    }
+}
+__tagtable(ATAG_NVIDIA_TEGRA, parse_tegra_tag);
+
+void __init tegra_nvos_kernel_init(void);
+
+void __init tegra_nvos_kernel_init(void)
+{
+    spin_lock_init(&gs_NvOsSpinLock);
+}
+#endif