/*
 * (C) Copyright 2010
 * MediaTek <www.MediaTek.com>
 *
 * MTK GPU Extension Device
 *
 */

#include <linux/cdev.h>
#include <linux/delay.h>
#include <linux/device.h>
#include <linux/fs.h>
#include <linux/hardirq.h>
#include <linux/init.h>
#include <linux/kallsyms.h>
#include <linux/miscdevice.h>
#include <linux/module.h>
#include <linux/poll.h>
#include <linux/proc_fs.h>
#include <linux/wait.h>
#include <linux/sched.h>
#include <linux/vmalloc.h>
#include <linux/disp_assert_layer.h>
#include <mach/system.h>
#include <linux/slab.h>
#include <linux/spinlock.h>
#include <linux/semaphore.h>
#include <linux/workqueue.h>
#include <linux/kthread.h>
#include <linux/aee.h>

#include "ged_debugFS.h"
#include "ged_log.h"
#include "ged_hal.h"
#include "ged_bridge.h"
#include "ged_profile_dvfs.h"
#include "ged_monitor_3D_fence.h"

#define GED_DRIVER_DEVICE_NAME "ged"

#define GED_IOCTL_PARAM_BUF_SIZE 0x3000 //12KB

#ifdef GED_DEBUG
#define GED_LOG_BUF_COMMON_FENCE "FENCE"
static GED_LOG_BUF_HANDLE ghLogBuf_FENCE = 0;
#define GED_LOG_BUF_COMMON_GLES "GLES"
static GED_LOG_BUF_HANDLE ghLogBuf_GLES = 0;
GED_LOG_BUF_HANDLE ghLogBuf_GED = 0;
#endif

static void* gvIOCTLParamBuf = NULL;

/******************************************************************************
 * GED File operations
 *****************************************************************************/
static int ged_open(struct inode *inode, struct file *filp)
{
    GED_LOGE("%s:%d:%d\n", __func__, MAJOR(inode->i_rdev), MINOR(inode->i_rdev));
    return 0;
}

static int ged_release(struct inode *inode, struct file *filp)
{
    GED_LOGE("%s:%d:%d\n", __func__, MAJOR(inode->i_rdev), MINOR(inode->i_rdev));
    return 0;
}

static unsigned int ged_poll(struct file *file, struct poll_table_struct *ptable)
{
    return 0;
}

static ssize_t ged_read(struct file *filp, char __user *buf, size_t count, loff_t *f_pos)
{
    return 0;
}

static ssize_t ged_write(struct file *filp, const char __user *buf, size_t count, loff_t *f_pos)
{
    return 0;
}

static long ged_dispatch(GED_BRIDGE_PACKAGE *psBridgePackageKM)
{
    int ret = -EFAULT;
    void *pvInt, *pvOut;
    typedef int (ged_bridge_func_type)(void *, void *);
    ged_bridge_func_type* pFunc = NULL;

	/* We make sure the both size and the sum of them are GE 0 integer.
	 * The sum will not overflow to zero, because we will get zero from two GE 0 integers
	 * if and only if they are both zero in a 2's complement numeral system.
	 * That is: if overflow happen, the sum will be a negative number.
	 */
    if (psBridgePackageKM->i32InBufferSize >= 0 && psBridgePackageKM->i32OutBufferSize >= 0
            && psBridgePackageKM->i32InBufferSize + psBridgePackageKM->i32OutBufferSize >= 0
            && psBridgePackageKM->i32InBufferSize + psBridgePackageKM->i32OutBufferSize
            < GED_IOCTL_PARAM_BUF_SIZE)
    {
        pvInt = gvIOCTLParamBuf;
        pvOut = (void *)((char *)pvInt + (uintptr_t)psBridgePackageKM->i32InBufferSize);
        if (psBridgePackageKM->i32InBufferSize > 0)
        {
            if (0 != ged_copy_from_user(pvInt, psBridgePackageKM->pvParamIn, psBridgePackageKM->i32InBufferSize))
            {
                GED_LOGE("ged_copy_from_user fail\n");
                return ret;
            }
        }

		/* Make sure that the UM will never break the KM.
		 * Check IO size are both matched the size of IO sturct.
		 */
#define SET_FUNC_AND_CHECK(func, struct_name) do { \
	pFunc = (ged_bridge_func_type *) func; \
	if (sizeof(GED_BRIDGE_IN_##struct_name) > psBridgePackageKM->i32InBufferSize || \
			sizeof(GED_BRIDGE_OUT_##struct_name) > psBridgePackageKM->i32OutBufferSize) { \
		GED_LOGE("GED_BRIDGE_COMMAND_##cmd fail io_size:%d/%d, expected: %zu/%zu", \
				psBridgePackageKM->i32InBufferSize, psBridgePackageKM->i32OutBufferSize, \
				sizeof(GED_BRIDGE_IN_##struct_name), sizeof(GED_BRIDGE_OUT_##struct_name)); \
		goto dispatch_exit; \
	} } while (0)

        // we will change the below switch into a function pointer mapping table in the future
        switch(GED_GET_BRIDGE_ID(psBridgePackageKM->ui32FunctionID))
        {
        case GED_BRIDGE_COMMAND_LOG_BUF_GET:
            SET_FUNC_AND_CHECK(ged_bridge_log_buf_get, LOGBUFGET);
            break;
        case GED_BRIDGE_COMMAND_LOG_BUF_WRITE:
            SET_FUNC_AND_CHECK(ged_bridge_log_buf_write, LOGBUFWRITE);
            break;
        case GED_BRIDGE_COMMAND_LOG_BUF_RESET:
            SET_FUNC_AND_CHECK(ged_bridge_log_buf_reset, LOGBUFRESET);
            break;            
        case GED_BRIDGE_COMMAND_BOOST_GPU_FREQ:
            SET_FUNC_AND_CHECK(ged_bridge_boost_gpu_freq, BOOSTGPUFREQ);
            break;
        case GED_BRIDGE_COMMAND_MONITOR_3D_FENCE:
            SET_FUNC_AND_CHECK(ged_bridge_monitor_3D_fence, MONITOR3DFENCE);
            break;
        default:
            GED_LOGE("Unknown Bridge ID: %u\n", GED_GET_BRIDGE_ID(psBridgePackageKM->ui32FunctionID));
            break;
        }

        if (pFunc)
        {
            ret = pFunc(pvInt, pvOut);
        }

        if (psBridgePackageKM->i32OutBufferSize > 0)
        {
            if (0 != ged_copy_to_user(psBridgePackageKM->pvParamOut, pvOut, psBridgePackageKM->i32OutBufferSize))
            {
                return ret;
            }
        }
    }

dispatch_exit:
    return ret;
}

DEFINE_SEMAPHORE(ged_dal_sem);

static long ged_ioctl(struct file *pFile, unsigned int ioctlCmd, unsigned long arg)
{
    int ret = -EFAULT;
	GED_BRIDGE_PACKAGE *psBridgePackageKM, *psBridgePackageUM = (GED_BRIDGE_PACKAGE*)arg;
	GED_BRIDGE_PACKAGE sBridgePackageKM;

    if (down_interruptible(&ged_dal_sem) < 0) 
    {
        GED_LOGE("Fail to down ged_dal_sem\n");
        return -ERESTARTSYS;
    }

	psBridgePackageKM = &sBridgePackageKM;
    if (0 != ged_copy_from_user(psBridgePackageKM, psBridgePackageUM, sizeof(GED_BRIDGE_PACKAGE)))
    {
        GED_LOGE("Fail to ged_copy_from_user\n");
        goto unlock_and_return;
    }

    ret = ged_dispatch(psBridgePackageKM);

unlock_and_return:
    up(&ged_dal_sem);

    return ret;
}

#ifdef CONFIG_COMPAT
static long ged_ioctl_compat(struct file *pFile, unsigned int ioctlCmd, unsigned long arg)
{
    typedef struct GED_BRIDGE_PACKAGE_32_TAG
    {
        unsigned int    ui32FunctionID;
        int             i32Size;
        unsigned int    ui32ParamIn;
        int             i32InBufferSize;
        unsigned int    ui32ParamOut;
        int             i32OutBufferSize;
    } GED_BRIDGE_PACKAGE_32;

    int ret = -EFAULT;
    GED_BRIDGE_PACKAGE sBridgePackageKM64;
    GED_BRIDGE_PACKAGE_32 sBridgePackageKM32;
    GED_BRIDGE_PACKAGE_32 *psBridgePackageKM32 = &sBridgePackageKM32;    
    GED_BRIDGE_PACKAGE_32 *psBridgePackageUM32 = (GED_BRIDGE_PACKAGE_32*)arg;

    if (down_interruptible(&ged_dal_sem) < 0) 
    {
        GED_LOGE("Fail to down ged_dal_sem\n");
        return -ERESTARTSYS;
    }

    if (0 != ged_copy_from_user(psBridgePackageKM32, psBridgePackageUM32, sizeof(GED_BRIDGE_PACKAGE_32)))
    {
        GED_LOGE("Fail to ged_copy_from_user\n");
        goto unlock_and_return;
    }

    sBridgePackageKM64.ui32FunctionID = psBridgePackageKM32->ui32FunctionID;
    sBridgePackageKM64.i32Size = sizeof(GED_BRIDGE_PACKAGE);
    sBridgePackageKM64.pvParamIn = (void*) ((size_t) psBridgePackageKM32->ui32ParamIn);
    sBridgePackageKM64.pvParamOut = (void*) ((size_t) psBridgePackageKM32->ui32ParamOut);
    sBridgePackageKM64.i32InBufferSize = psBridgePackageKM32->i32InBufferSize;
    sBridgePackageKM64.i32OutBufferSize = psBridgePackageKM32->i32OutBufferSize;
    
    ret = ged_dispatch(&sBridgePackageKM64);
    
unlock_and_return:
    up(&ged_dal_sem);
    
    return ret;
}
#endif

/******************************************************************************
 * Module related
 *****************************************************************************/

static struct file_operations ged_fops = {
    .owner = THIS_MODULE,
    .open = ged_open,
    .release = ged_release,
    .poll = ged_poll,
    .read = ged_read,
    .write = ged_write,
    .unlocked_ioctl = ged_ioctl,
#ifdef CONFIG_COMPAT
    .compat_ioctl = ged_ioctl_compat,
#endif
};

#if 0
static struct miscdevice ged_dev = {
    .minor = MISC_DYNAMIC_MINOR,
    .name = "ged",
    .fops = &ged_fops,
};
#endif

static void ged_exit(void)
{
#ifdef GED_DEBUG
    ged_log_buf_free(ghLogBuf_GED);
    ghLogBuf_GED = 0;
    ged_log_buf_free(ghLogBuf_GLES);
    ghLogBuf_GLES = 0;
    ged_log_buf_free(ghLogBuf_FENCE);
    ghLogBuf_FENCE = 0;
#endif

    ged_profile_dvfs_exit();

    ged_hal_exit();

    ged_log_system_exit();

    ged_debugFS_exit();

    remove_proc_entry(GED_DRIVER_DEVICE_NAME, NULL);

    if (gvIOCTLParamBuf)
    {
        vfree(gvIOCTLParamBuf);
        gvIOCTLParamBuf = NULL;
    }
}

static int ged_init(void)
{
    GED_ERROR err = GED_ERROR_FAIL;

    gvIOCTLParamBuf = vmalloc(GED_IOCTL_PARAM_BUF_SIZE);
    if (NULL == gvIOCTLParamBuf)
    {
        err = GED_ERROR_OOM;
        goto ERROR;
    }

    if (NULL == proc_create(GED_DRIVER_DEVICE_NAME, 0644, NULL, &ged_fops))
    {
        err = GED_ERROR_FAIL;
        GED_LOGE("ged: failed to register ged proc entry!\n");
        goto ERROR;
    }

    err = ged_debugFS_init();
    if (unlikely(err != GED_OK))
    {
        GED_LOGE("ged: failed to init debug FS!\n");
        goto ERROR;
    }

    err = ged_log_system_init();
    if (unlikely(err != GED_OK))
    {
        GED_LOGE("ged: failed to create gedlog entry!\n");
        goto ERROR;
    }

    err = ged_hal_init();
    if (unlikely(err != GED_OK))
    {
        GED_LOGE("ged: failed to create hal entry!\n");
        goto ERROR;
    }

    err = ged_profile_dvfs_init();
    if (unlikely(err != GED_OK))
    {
        GED_LOGE("ged: failed to init profile dvfs!\n");
        goto ERROR;
    }

#ifdef GED_DEBUG
    ghLogBuf_FENCE = ged_log_buf_alloc(256, 128 * 256, GED_LOG_BUF_TYPE_RINGBUFFER, GED_LOG_BUF_COMMON_FENCE, NULL);
    ghLogBuf_GLES = ged_log_buf_alloc(160, 128 * 160, GED_LOG_BUF_TYPE_RINGBUFFER, GED_LOG_BUF_COMMON_GLES, NULL);
    ghLogBuf_GED = ged_log_buf_alloc(32, 64 * 32, GED_LOG_BUF_TYPE_RINGBUFFER, "GED internal", NULL);
#endif

    return 0;

ERROR:
    ged_exit();

    return -EFAULT;
}

module_init(ged_init);
module_exit(ged_exit);

MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("MediaTek GED Driver");
MODULE_AUTHOR("MediaTek Inc.");