Adding support for MOXA ART SoC. Testing port of linux-2.6.32.60-moxart.

[linux-3.6.7-moxart.git] / drivers / staging / tidspbridge / rmgr / drv.c

/*
 * drv.c
 *
 * DSP-BIOS Bridge driver support functions for TI OMAP processors.
 *
 * DSP/BIOS Bridge resource allocation module.
 *
 * Copyright (C) 2005-2006 Texas Instruments, Inc.
 *
 * This package 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.
 *
 * THIS PACKAGE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
 * WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.
 */
#include <linux/types.h>
#include <linux/list.h>

/*  ----------------------------------- Host OS */
#include <dspbridge/host_os.h>

/*  ----------------------------------- DSP/BIOS Bridge */
#include <dspbridge/dbdefs.h>

/*  ----------------------------------- This */
#include <dspbridge/drv.h>
#include <dspbridge/dev.h>

#include <dspbridge/node.h>
#include <dspbridge/proc.h>
#include <dspbridge/strm.h>
#include <dspbridge/nodepriv.h>
#include <dspbridge/dspchnl.h>
#include <dspbridge/resourcecleanup.h>

/*  ----------------------------------- Defines, Data Structures, Typedefs */
struct drv_object {
        struct list_head dev_list;
        struct list_head dev_node_string;
};

/*
 *  This is the Device Extension. Named with the Prefix
 *  DRV_ since it is living in this module
 */
struct drv_ext {
        struct list_head link;
        char sz_string[MAXREGPATHLENGTH];
};

/*  ----------------------------------- Globals */
static bool ext_phys_mem_pool_enabled;
struct ext_phys_mem_pool {
        u32 phys_mem_base;
        u32 phys_mem_size;
        u32 virt_mem_base;
        u32 next_phys_alloc_ptr;
};
static struct ext_phys_mem_pool ext_mem_pool;

/*  ----------------------------------- Function Prototypes */
static int request_bridge_resources(struct cfg_hostres *res);


/* GPP PROCESS CLEANUP CODE */

static int drv_proc_free_node_res(int id, void *p, void *data);

/* Allocate and add a node resource element
* This function is called from .Node_Allocate. */
int drv_insert_node_res_element(void *hnode, void *node_resource,
                                       void *process_ctxt)
{
        struct node_res_object **node_res_obj =
            (struct node_res_object **)node_resource;
        struct process_context *ctxt = (struct process_context *)process_ctxt;
        int status = 0;
        int retval;

        *node_res_obj = kzalloc(sizeof(struct node_res_object), GFP_KERNEL);
        if (!*node_res_obj) {
                status = -ENOMEM;
                goto func_end;
        }

        (*node_res_obj)->node = hnode;
        retval = idr_get_new(ctxt->node_id, *node_res_obj,
                                                &(*node_res_obj)->id);
        if (retval == -EAGAIN) {
                if (!idr_pre_get(ctxt->node_id, GFP_KERNEL)) {
                        pr_err("%s: OUT OF MEMORY\n", __func__);
                        status = -ENOMEM;
                        goto func_end;
                }

                retval = idr_get_new(ctxt->node_id, *node_res_obj,
                                                &(*node_res_obj)->id);
        }
        if (retval) {
                pr_err("%s: FAILED, IDR is FULL\n", __func__);
                status = -EFAULT;
        }
func_end:
        if (status)
                kfree(*node_res_obj);

        return status;
}

/* Release all Node resources and its context
 * Actual Node De-Allocation */
static int drv_proc_free_node_res(int id, void *p, void *data)
{
        struct process_context *ctxt = data;
        int status;
        struct node_res_object *node_res_obj = p;
        u32 node_state;

        if (node_res_obj->node_allocated) {
                node_state = node_get_state(node_res_obj->node);
                if (node_state <= NODE_DELETING) {
                        if ((node_state == NODE_RUNNING) ||
                            (node_state == NODE_PAUSED) ||
                            (node_state == NODE_TERMINATING))
                                node_terminate
                                    (node_res_obj->node, &status);

                        node_delete(node_res_obj, ctxt);
                }
        }

        return 0;
}

/* Release all Mapped and Reserved DMM resources */
int drv_remove_all_dmm_res_elements(void *process_ctxt)
{
        struct process_context *ctxt = (struct process_context *)process_ctxt;
        int status = 0;
        struct dmm_map_object *temp_map, *map_obj;
        struct dmm_rsv_object *temp_rsv, *rsv_obj;

        /* Free DMM mapped memory resources */
        list_for_each_entry_safe(map_obj, temp_map, &ctxt->dmm_map_list, link) {
                status = proc_un_map(ctxt->processor,
                                     (void *)map_obj->dsp_addr, ctxt);
                if (status)
                        pr_err("%s: proc_un_map failed!"
                               " status = 0x%xn", __func__, status);
        }

        /* Free DMM reserved memory resources */
        list_for_each_entry_safe(rsv_obj, temp_rsv, &ctxt->dmm_rsv_list, link) {
                status = proc_un_reserve_memory(ctxt->processor, (void *)
                                                rsv_obj->dsp_reserved_addr,
                                                ctxt);
                if (status)
                        pr_err("%s: proc_un_reserve_memory failed!"
                               " status = 0x%xn", __func__, status);
        }
        return status;
}

/* Update Node allocation status */
void drv_proc_node_update_status(void *node_resource, s32 status)
{
        struct node_res_object *node_res_obj =
            (struct node_res_object *)node_resource;
        node_res_obj->node_allocated = status;
}

/* Update Node Heap status */
void drv_proc_node_update_heap_status(void *node_resource, s32 status)
{
        struct node_res_object *node_res_obj =
            (struct node_res_object *)node_resource;
        node_res_obj->heap_allocated = status;
}

/* Release all Node resources and its context
* This is called from .bridge_release.
 */
int drv_remove_all_node_res_elements(void *process_ctxt)
{
        struct process_context *ctxt = process_ctxt;

        idr_for_each(ctxt->node_id, drv_proc_free_node_res, ctxt);
        idr_destroy(ctxt->node_id);

        return 0;
}

/* Allocate the STRM resource element
* This is called after the actual resource is allocated
 */
int drv_proc_insert_strm_res_element(void *stream_obj,
                                            void *strm_res, void *process_ctxt)
{
        struct strm_res_object **pstrm_res =
            (struct strm_res_object **)strm_res;
        struct process_context *ctxt = (struct process_context *)process_ctxt;
        int status = 0;
        int retval;

        *pstrm_res = kzalloc(sizeof(struct strm_res_object), GFP_KERNEL);
        if (*pstrm_res == NULL) {
                status = -EFAULT;
                goto func_end;
        }

        (*pstrm_res)->stream = stream_obj;
        retval = idr_get_new(ctxt->stream_id, *pstrm_res,
                                                &(*pstrm_res)->id);
        if (retval == -EAGAIN) {
                if (!idr_pre_get(ctxt->stream_id, GFP_KERNEL)) {
                        pr_err("%s: OUT OF MEMORY\n", __func__);
                        status = -ENOMEM;
                        goto func_end;
                }

                retval = idr_get_new(ctxt->stream_id, *pstrm_res,
                                                &(*pstrm_res)->id);
        }
        if (retval) {
                pr_err("%s: FAILED, IDR is FULL\n", __func__);
                status = -EPERM;
        }

func_end:
        return status;
}

static int drv_proc_free_strm_res(int id, void *p, void *process_ctxt)
{
        struct process_context *ctxt = process_ctxt;
        struct strm_res_object *strm_res = p;
        struct stream_info strm_info;
        struct dsp_streaminfo user;
        u8 **ap_buffer = NULL;
        u8 *buf_ptr;
        u32 ul_bytes;
        u32 dw_arg;
        s32 ul_buf_size;

        if (strm_res->num_bufs) {
                ap_buffer = kmalloc((strm_res->num_bufs *
                                       sizeof(u8 *)), GFP_KERNEL);
                if (ap_buffer) {
                        strm_free_buffer(strm_res,
                                                  ap_buffer,
                                                  strm_res->num_bufs,
                                                  ctxt);
                        kfree(ap_buffer);
                }
        }
        strm_info.user_strm = &user;
        user.number_bufs_in_stream = 0;
        strm_get_info(strm_res->stream, &strm_info, sizeof(strm_info));
        while (user.number_bufs_in_stream--)
                strm_reclaim(strm_res->stream, &buf_ptr, &ul_bytes,
                             (u32 *) &ul_buf_size, &dw_arg);
        strm_close(strm_res, ctxt);
        return 0;
}

/* Release all Stream resources and its context
* This is called from .bridge_release.
 */
int drv_remove_all_strm_res_elements(void *process_ctxt)
{
        struct process_context *ctxt = process_ctxt;

        idr_for_each(ctxt->stream_id, drv_proc_free_strm_res, ctxt);
        idr_destroy(ctxt->stream_id);

        return 0;
}

/* Updating the stream resource element */
int drv_proc_update_strm_res(u32 num_bufs, void *strm_resources)
{
        int status = 0;
        struct strm_res_object **strm_res =
            (struct strm_res_object **)strm_resources;

        (*strm_res)->num_bufs = num_bufs;
        return status;
}

/* GPP PROCESS CLEANUP CODE END */

/*
 *  ======== = drv_create ======== =
 *  Purpose:
 *      DRV Object gets created only once during Driver Loading.
 */
int drv_create(struct drv_object **drv_obj)
{
        int status = 0;
        struct drv_object *pdrv_object = NULL;
        struct drv_data *drv_datap = dev_get_drvdata(bridge);

        pdrv_object = kzalloc(sizeof(struct drv_object), GFP_KERNEL);
        if (pdrv_object) {
                /* Create and Initialize List of device objects */
                INIT_LIST_HEAD(&pdrv_object->dev_list);
                INIT_LIST_HEAD(&pdrv_object->dev_node_string);
        } else {
                status = -ENOMEM;
        }
        /* Store the DRV Object in the driver data */
        if (!status) {
                if (drv_datap) {
                        drv_datap->drv_object = (void *)pdrv_object;
                } else {
                        status = -EPERM;
                        pr_err("%s: Failed to store DRV object\n", __func__);
                }
        }

        if (!status) {
                *drv_obj = pdrv_object;
        } else {
                /* Free the DRV Object */
                kfree(pdrv_object);
        }

        return status;
}

/*
 *  ======== = drv_destroy ======== =
 *  purpose:
 *      Invoked during bridge de-initialization
 */
int drv_destroy(struct drv_object *driver_obj)
{
        int status = 0;
        struct drv_object *pdrv_object = (struct drv_object *)driver_obj;
        struct drv_data *drv_datap = dev_get_drvdata(bridge);

        kfree(pdrv_object);
        /* Update the DRV Object in the driver data */
        if (drv_datap) {
                drv_datap->drv_object = NULL;
        } else {
                status = -EPERM;
                pr_err("%s: Failed to store DRV object\n", __func__);
        }

        return status;
}

/*
 *  ======== drv_get_dev_object ========
 *  Purpose:
 *      Given a index, returns a handle to DevObject from the list.
 */
int drv_get_dev_object(u32 index, struct drv_object *hdrv_obj,
                              struct dev_object **device_obj)
{
        int status = 0;
        struct dev_object *dev_obj;
        u32 i;

        dev_obj = (struct dev_object *)drv_get_first_dev_object();
        for (i = 0; i < index; i++) {
                dev_obj =
                    (struct dev_object *)drv_get_next_dev_object((u32) dev_obj);
        }
        if (dev_obj) {
                *device_obj = (struct dev_object *)dev_obj;
        } else {
                *device_obj = NULL;
                status = -EPERM;
        }

        return status;
}

/*
 *  ======== drv_get_first_dev_object ========
 *  Purpose:
 *      Retrieve the first Device Object handle from an internal linked list of
 *      of DEV_OBJECTs maintained by DRV.
 */
u32 drv_get_first_dev_object(void)
{
        u32 dw_dev_object = 0;
        struct drv_object *pdrv_obj;
        struct drv_data *drv_datap = dev_get_drvdata(bridge);

        if (drv_datap && drv_datap->drv_object) {
                pdrv_obj = drv_datap->drv_object;
                if (!list_empty(&pdrv_obj->dev_list))
                        dw_dev_object = (u32) pdrv_obj->dev_list.next;
        } else {
                pr_err("%s: Failed to retrieve the object handle\n", __func__);
        }

        return dw_dev_object;
}

/*
 *  ======== DRV_GetFirstDevNodeString ========
 *  Purpose:
 *      Retrieve the first Device Extension from an internal linked list of
 *      of Pointer to dev_node Strings maintained by DRV.
 */
u32 drv_get_first_dev_extension(void)
{
        u32 dw_dev_extension = 0;
        struct drv_object *pdrv_obj;
        struct drv_data *drv_datap = dev_get_drvdata(bridge);

        if (drv_datap && drv_datap->drv_object) {
                pdrv_obj = drv_datap->drv_object;
                if (!list_empty(&pdrv_obj->dev_node_string)) {
                        dw_dev_extension =
                            (u32) pdrv_obj->dev_node_string.next;
                }
        } else {
                pr_err("%s: Failed to retrieve the object handle\n", __func__);
        }

        return dw_dev_extension;
}

/*
 *  ======== drv_get_next_dev_object ========
 *  Purpose:
 *      Retrieve the next Device Object handle from an internal linked list of
 *      of DEV_OBJECTs maintained by DRV, after having previously called
 *      drv_get_first_dev_object() and zero or more DRV_GetNext.
 */
u32 drv_get_next_dev_object(u32 hdev_obj)
{
        u32 dw_next_dev_object = 0;
        struct drv_object *pdrv_obj;
        struct drv_data *drv_datap = dev_get_drvdata(bridge);
        struct list_head *curr;

        if (drv_datap && drv_datap->drv_object) {
                pdrv_obj = drv_datap->drv_object;
                if (!list_empty(&pdrv_obj->dev_list)) {
                        curr = (struct list_head *)hdev_obj;
                        if (list_is_last(curr, &pdrv_obj->dev_list))
                                return 0;
                        dw_next_dev_object = (u32) curr->next;
                }
        } else {
                pr_err("%s: Failed to retrieve the object handle\n", __func__);
        }

        return dw_next_dev_object;
}

/*
 *  ======== drv_get_next_dev_extension ========
 *  Purpose:
 *      Retrieve the next Device Extension from an internal linked list of
 *      of pointer to DevNodeString maintained by DRV, after having previously
 *      called drv_get_first_dev_extension() and zero or more
 *      drv_get_next_dev_extension().
 */
u32 drv_get_next_dev_extension(u32 dev_extension)
{
        u32 dw_dev_extension = 0;
        struct drv_object *pdrv_obj;
        struct drv_data *drv_datap = dev_get_drvdata(bridge);
        struct list_head *curr;

        if (drv_datap && drv_datap->drv_object) {
                pdrv_obj = drv_datap->drv_object;
                if (!list_empty(&pdrv_obj->dev_node_string)) {
                        curr = (struct list_head *)dev_extension;
                        if (list_is_last(curr, &pdrv_obj->dev_node_string))
                                return 0;
                        dw_dev_extension = (u32) curr->next;
                }
        } else {
                pr_err("%s: Failed to retrieve the object handle\n", __func__);
        }

        return dw_dev_extension;
}

/*
 *  ======== drv_insert_dev_object ========
 *  Purpose:
 *      Insert a DevObject into the list of Manager object.
 */
int drv_insert_dev_object(struct drv_object *driver_obj,
                                 struct dev_object *hdev_obj)
{
        struct drv_object *pdrv_object = (struct drv_object *)driver_obj;

        list_add_tail((struct list_head *)hdev_obj, &pdrv_object->dev_list);

        return 0;
}

/*
 *  ======== drv_remove_dev_object ========
 *  Purpose:
 *      Search for and remove a DeviceObject from the given list of DRV
 *      objects.
 */
int drv_remove_dev_object(struct drv_object *driver_obj,
                                 struct dev_object *hdev_obj)
{
        int status = -EPERM;
        struct drv_object *pdrv_object = (struct drv_object *)driver_obj;
        struct list_head *cur_elem;

        /* Search list for p_proc_object: */
        list_for_each(cur_elem, &pdrv_object->dev_list) {
                /* If found, remove it. */
                if ((struct dev_object *)cur_elem == hdev_obj) {
                        list_del(cur_elem);
                        status = 0;
                        break;
                }
        }

        return status;
}

/*
 *  ======== drv_request_resources ========
 *  Purpose:
 *      Requests  resources from the OS.
 */
int drv_request_resources(u32 dw_context, u32 *dev_node_strg)
{
        int status = 0;
        struct drv_object *pdrv_object;
        struct drv_ext *pszdev_node;
        struct drv_data *drv_datap = dev_get_drvdata(bridge);

        /*
         *  Allocate memory to hold the string. This will live until
         *  it is freed in the Release resources. Update the driver object
         *  list.
         */

        if (!drv_datap || !drv_datap->drv_object)
                status = -ENODATA;
        else
                pdrv_object = drv_datap->drv_object;

        if (!status) {
                pszdev_node = kzalloc(sizeof(struct drv_ext), GFP_KERNEL);
                if (pszdev_node) {
                        strncpy(pszdev_node->sz_string,
                                (char *)dw_context, MAXREGPATHLENGTH - 1);
                        pszdev_node->sz_string[MAXREGPATHLENGTH - 1] = '\0';
                        /* Update the Driver Object List */
                        *dev_node_strg = (u32) pszdev_node->sz_string;
                        list_add_tail(&pszdev_node->link,
                                        &pdrv_object->dev_node_string);
                } else {
                        status = -ENOMEM;
                        *dev_node_strg = 0;
                }
        } else {
                dev_dbg(bridge, "%s: Failed to get Driver Object from Registry",
                        __func__);
                *dev_node_strg = 0;
        }

        return status;
}

/*
 *  ======== drv_release_resources ========
 *  Purpose:
 *      Releases  resources from the OS.
 */
int drv_release_resources(u32 dw_context, struct drv_object *hdrv_obj)
{
        int status = 0;
        struct drv_ext *pszdev_node;

        /*
         *  Irrespective of the status go ahead and clean it
         *  The following will over write the status.
         */
        for (pszdev_node = (struct drv_ext *)drv_get_first_dev_extension();
             pszdev_node != NULL; pszdev_node = (struct drv_ext *)
             drv_get_next_dev_extension((u32) pszdev_node)) {
                if ((u32) pszdev_node == dw_context) {
                        /* Found it */
                        /* Delete from the Driver object list */
                        list_del(&pszdev_node->link);
                        kfree(pszdev_node);
                        break;
                }
        }
        return status;
}

/*
 *  ======== request_bridge_resources ========
 *  Purpose:
 *      Reserves shared memory for bridge.
 */
static int request_bridge_resources(struct cfg_hostres *res)
{
        struct cfg_hostres *host_res = res;

        /* num_mem_windows must not be more than CFG_MAXMEMREGISTERS */
        host_res->num_mem_windows = 2;

        /* First window is for DSP internal memory */
        dev_dbg(bridge, "mem_base[0] 0x%x\n", host_res->mem_base[0]);
        dev_dbg(bridge, "mem_base[3] 0x%x\n", host_res->mem_base[3]);
        dev_dbg(bridge, "dmmu_base %p\n", host_res->dmmu_base);

        /* for 24xx base port is not mapping the mamory for DSP
         * internal memory TODO Do a ioremap here */
        /* Second window is for DSP external memory shared with MPU */

        /* These are hard-coded values */
        host_res->birq_registers = 0;
        host_res->birq_attrib = 0;
        host_res->offset_for_monitor = 0;
        host_res->chnl_offset = 0;
        /* CHNL_MAXCHANNELS */
        host_res->num_chnls = CHNL_MAXCHANNELS;
        host_res->chnl_buf_size = 0x400;

        return 0;
}

/*
 *  ======== drv_request_bridge_res_dsp ========
 *  Purpose:
 *      Reserves shared memory for bridge.
 */
int drv_request_bridge_res_dsp(void **phost_resources)
{
        int status = 0;
        struct cfg_hostres *host_res;
        u32 dw_buff_size;
        u32 dma_addr;
        u32 shm_size;
        struct drv_data *drv_datap = dev_get_drvdata(bridge);

        dw_buff_size = sizeof(struct cfg_hostres);

        host_res = kzalloc(dw_buff_size, GFP_KERNEL);

        if (host_res != NULL) {
                request_bridge_resources(host_res);
                /* num_mem_windows must not be more than CFG_MAXMEMREGISTERS */
                host_res->num_mem_windows = 4;

                host_res->mem_base[0] = 0;
                host_res->mem_base[2] = (u32) ioremap(OMAP_DSP_MEM1_BASE,
                                                         OMAP_DSP_MEM1_SIZE);
                host_res->mem_base[3] = (u32) ioremap(OMAP_DSP_MEM2_BASE,
                                                         OMAP_DSP_MEM2_SIZE);
                host_res->mem_base[4] = (u32) ioremap(OMAP_DSP_MEM3_BASE,
                                                         OMAP_DSP_MEM3_SIZE);
                host_res->per_base = ioremap(OMAP_PER_CM_BASE,
                                                OMAP_PER_CM_SIZE);
                host_res->per_pm_base = (u32) ioremap(OMAP_PER_PRM_BASE,
                                                         OMAP_PER_PRM_SIZE);
                host_res->core_pm_base = (u32) ioremap(OMAP_CORE_PRM_BASE,
                                                          OMAP_CORE_PRM_SIZE);
                host_res->dmmu_base = ioremap(OMAP_DMMU_BASE,
                                                 OMAP_DMMU_SIZE);

                dev_dbg(bridge, "mem_base[0] 0x%x\n",
                        host_res->mem_base[0]);
                dev_dbg(bridge, "mem_base[1] 0x%x\n",
                        host_res->mem_base[1]);
                dev_dbg(bridge, "mem_base[2] 0x%x\n",
                        host_res->mem_base[2]);
                dev_dbg(bridge, "mem_base[3] 0x%x\n",
                        host_res->mem_base[3]);
                dev_dbg(bridge, "mem_base[4] 0x%x\n",
                        host_res->mem_base[4]);
                dev_dbg(bridge, "dmmu_base %p\n", host_res->dmmu_base);

                shm_size = drv_datap->shm_size;
                if (shm_size >= 0x10000) {
                        /* Allocate Physically contiguous,
                         * non-cacheable  memory */
                        host_res->mem_base[1] =
                            (u32) mem_alloc_phys_mem(shm_size, 0x100000,
                                                     &dma_addr);
                        if (host_res->mem_base[1] == 0) {
                                status = -ENOMEM;
                                pr_err("shm reservation Failed\n");
                        } else {
                                host_res->mem_length[1] = shm_size;
                                host_res->mem_phys[1] = dma_addr;

                                dev_dbg(bridge, "%s: Bridge shm address 0x%x "
                                        "dma_addr %x size %x\n", __func__,
                                        host_res->mem_base[1],
                                        dma_addr, shm_size);
                        }
                }
                if (!status) {
                        /* These are hard-coded values */
                        host_res->birq_registers = 0;
                        host_res->birq_attrib = 0;
                        host_res->offset_for_monitor = 0;
                        host_res->chnl_offset = 0;
                        /* CHNL_MAXCHANNELS */
                        host_res->num_chnls = CHNL_MAXCHANNELS;
                        host_res->chnl_buf_size = 0x400;
                        dw_buff_size = sizeof(struct cfg_hostres);
                }
                *phost_resources = host_res;
        }
        /* End Mem alloc */
        return status;
}

void mem_ext_phys_pool_init(u32 pool_phys_base, u32 pool_size)
{
        u32 pool_virt_base;

        /* get the virtual address for the physical memory pool passed */
        pool_virt_base = (u32) ioremap(pool_phys_base, pool_size);

        if ((void **)pool_virt_base == NULL) {
                pr_err("%s: external physical memory map failed\n", __func__);
                ext_phys_mem_pool_enabled = false;
        } else {
                ext_mem_pool.phys_mem_base = pool_phys_base;
                ext_mem_pool.phys_mem_size = pool_size;
                ext_mem_pool.virt_mem_base = pool_virt_base;
                ext_mem_pool.next_phys_alloc_ptr = pool_phys_base;
                ext_phys_mem_pool_enabled = true;
        }
}

void mem_ext_phys_pool_release(void)
{
        if (ext_phys_mem_pool_enabled) {
                iounmap((void *)(ext_mem_pool.virt_mem_base));
                ext_phys_mem_pool_enabled = false;
        }
}

/*
 *  ======== mem_ext_phys_mem_alloc ========
 *  Purpose:
 *     Allocate physically contiguous, uncached memory from external memory pool
 */

static void *mem_ext_phys_mem_alloc(u32 bytes, u32 align, u32 * phys_addr)
{
        u32 new_alloc_ptr;
        u32 offset;
        u32 virt_addr;

        if (align == 0)
                align = 1;

        if (bytes > ((ext_mem_pool.phys_mem_base + ext_mem_pool.phys_mem_size)
                     - ext_mem_pool.next_phys_alloc_ptr)) {
                phys_addr = NULL;
                return NULL;
        } else {
                offset = (ext_mem_pool.next_phys_alloc_ptr & (align - 1));
                if (offset == 0)
                        new_alloc_ptr = ext_mem_pool.next_phys_alloc_ptr;
                else
                        new_alloc_ptr = (ext_mem_pool.next_phys_alloc_ptr) +
                            (align - offset);
                if ((new_alloc_ptr + bytes) <=
                    (ext_mem_pool.phys_mem_base + ext_mem_pool.phys_mem_size)) {
                        /* we can allocate */
                        *phys_addr = new_alloc_ptr;
                        ext_mem_pool.next_phys_alloc_ptr =
                            new_alloc_ptr + bytes;
                        virt_addr =
                            ext_mem_pool.virt_mem_base + (new_alloc_ptr -
                                                          ext_mem_pool.
                                                          phys_mem_base);
                        return (void *)virt_addr;
                } else {
                        *phys_addr = 0;
                        return NULL;
                }
        }
}

/*
 *  ======== mem_alloc_phys_mem ========
 *  Purpose:
 *      Allocate physically contiguous, uncached memory
 */
void *mem_alloc_phys_mem(u32 byte_size, u32 align_mask,
                                u32 *physical_address)
{
        void *va_mem = NULL;
        dma_addr_t pa_mem;

        if (byte_size > 0) {
                if (ext_phys_mem_pool_enabled) {
                        va_mem = mem_ext_phys_mem_alloc(byte_size, align_mask,
                                                        (u32 *) &pa_mem);
                } else
                        va_mem = dma_alloc_coherent(NULL, byte_size, &pa_mem,
                                                                GFP_KERNEL);
                if (va_mem == NULL)
                        *physical_address = 0;
                else
                        *physical_address = pa_mem;
        }
        return va_mem;
}

/*
 *  ======== mem_free_phys_mem ========
 *  Purpose:
 *      Free the given block of physically contiguous memory.
 */
void mem_free_phys_mem(void *virtual_address, u32 physical_address,
                       u32 byte_size)
{
        if (!ext_phys_mem_pool_enabled)
                dma_free_coherent(NULL, byte_size, virtual_address,
                                  physical_address);
}