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authorRafał Miłecki <rafal@milecki.pl>2017-03-22 21:09:00 +0100
committerRafał Miłecki <rafal@milecki.pl>2017-03-24 08:06:35 +0100
commitfce21ae4ccfcee0c28fb18f5507e145fb0b02dec (patch)
tree6c29b7c1f65945991d0cae13af012e6c14adc713 /target/linux/brcm2708/patches-4.9/950-0037-cma-Add-vc_cma-driver-to-enable-use-of-CMA.patch
parent46e390322a58bdc632ee43fdf9d14115dac26e7a (diff)
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brcm2708: rename all patches from raspberrypi git tree to use 950 prefix
Right now all brcm2708 patches are extracted from the non-mainline raspberrypi/linux git tree. Many of them are hacks and/or are unneeded in LEDE. Raspberry Pi is getting better and better mainline support so it would be nice to finally start maintaining patches in a cleaner way: 1) Backport patches accepted in upstream tree 2) Start using upstream drivers 3) Pick only these patches that are needed for more complete support Handling above tasks requires grouping patches - ideally using the same prefixes as generic ones. It means we should rename existing patches to use some high prefix. This will allow e.g. use 0xx for backported code. Signed-off-by: Rafał Miłecki <rafal@milecki.pl> Acked-by: Florian Fainelli <f.fainelli@gmail.com> Acked-by: Stijn Tintel <stijn@linux-ipv6.be>
Diffstat (limited to 'target/linux/brcm2708/patches-4.9/950-0037-cma-Add-vc_cma-driver-to-enable-use-of-CMA.patch')
-rw-r--r--target/linux/brcm2708/patches-4.9/950-0037-cma-Add-vc_cma-driver-to-enable-use-of-CMA.patch1319
1 files changed, 1319 insertions, 0 deletions
diff --git a/target/linux/brcm2708/patches-4.9/950-0037-cma-Add-vc_cma-driver-to-enable-use-of-CMA.patch b/target/linux/brcm2708/patches-4.9/950-0037-cma-Add-vc_cma-driver-to-enable-use-of-CMA.patch
new file mode 100644
index 0000000000..50bad76c51
--- /dev/null
+++ b/target/linux/brcm2708/patches-4.9/950-0037-cma-Add-vc_cma-driver-to-enable-use-of-CMA.patch
@@ -0,0 +1,1319 @@
+From 4d96064d4c95d73d22563cea403eccd72e7b0da0 Mon Sep 17 00:00:00 2001
+From: popcornmix <popcornmix@gmail.com>
+Date: Wed, 3 Jul 2013 00:31:47 +0100
+Subject: [PATCH] cma: Add vc_cma driver to enable use of CMA
+MIME-Version: 1.0
+Content-Type: text/plain; charset=UTF-8
+Content-Transfer-Encoding: 8bit
+
+Signed-off-by: popcornmix <popcornmix@gmail.com>
+
+vc_cma: Make the vc_cma area the default contiguous DMA area
+
+vc_cma: Provide empty functions when module is not built
+
+Providing empty functions saves the users from guarding the
+function call with an #if clause.
+Move __init markings from prototypes to functions.
+
+Signed-off-by: Noralf Trønnes <noralf@tronnes.org>
+---
+ drivers/char/Kconfig | 2 +
+ drivers/char/Makefile | 1 +
+ drivers/char/broadcom/Kconfig | 15 +
+ drivers/char/broadcom/Makefile | 1 +
+ drivers/char/broadcom/vc_cma/Makefile | 7 +
+ drivers/char/broadcom/vc_cma/vc_cma.c | 1193 +++++++++++++++++++++++++++++++++
+ include/linux/broadcom/vc_cma.h | 36 +
+ 7 files changed, 1255 insertions(+)
+ create mode 100644 drivers/char/broadcom/Kconfig
+ create mode 100644 drivers/char/broadcom/Makefile
+ create mode 100644 drivers/char/broadcom/vc_cma/Makefile
+ create mode 100644 drivers/char/broadcom/vc_cma/vc_cma.c
+ create mode 100644 include/linux/broadcom/vc_cma.h
+
+--- a/drivers/char/Kconfig
++++ b/drivers/char/Kconfig
+@@ -4,6 +4,8 @@
+
+ menu "Character devices"
+
++source "drivers/char/broadcom/Kconfig"
++
+ source "drivers/tty/Kconfig"
+
+ config DEVMEM
+--- a/drivers/char/Makefile
++++ b/drivers/char/Makefile
+@@ -60,3 +60,4 @@ js-rtc-y = rtc.o
+ obj-$(CONFIG_TILE_SROM) += tile-srom.o
+ obj-$(CONFIG_XILLYBUS) += xillybus/
+ obj-$(CONFIG_POWERNV_OP_PANEL) += powernv-op-panel.o
++obj-$(CONFIG_BRCM_CHAR_DRIVERS) += broadcom/
+--- /dev/null
++++ b/drivers/char/broadcom/Kconfig
+@@ -0,0 +1,15 @@
++#
++# Broadcom char driver config
++#
++
++menuconfig BRCM_CHAR_DRIVERS
++ bool "Broadcom Char Drivers"
++ help
++ Broadcom's char drivers
++
++config BCM_VC_CMA
++ bool "Videocore CMA"
++ depends on CMA && BRCM_CHAR_DRIVERS && BCM2708_VCHIQ
++ default n
++ help
++ Helper for videocore CMA access.
+--- /dev/null
++++ b/drivers/char/broadcom/Makefile
+@@ -0,0 +1 @@
++obj-$(CONFIG_BCM_VC_CMA) += vc_cma/
+--- /dev/null
++++ b/drivers/char/broadcom/vc_cma/Makefile
+@@ -0,0 +1,7 @@
++ccflags-$(CONFIG_BCM_VC_CMA) += -Wall -Wstrict-prototypes -Wno-trigraphs -Werror
++ccflags-$(CONFIG_BCM_VC_CMA) += -Iinclude/linux/broadcom -Idrivers/staging/vc04_services -Idrivers/staging/vc04_services/interface/vchi -Idrivers/staging/vc04_services/interface/vchiq_arm
++ccflags-$(CONFIG_BCM_VC_CMA) += -D__KERNEL__ -D__linux__
++
++obj-$(CONFIG_BCM_VC_CMA) += vc-cma.o
++
++vc-cma-objs := vc_cma.o
+--- /dev/null
++++ b/drivers/char/broadcom/vc_cma/vc_cma.c
+@@ -0,0 +1,1193 @@
++/**
++ * Copyright (c) 2010-2012 Broadcom. All rights reserved.
++ *
++ * Redistribution and use in source and binary forms, with or without
++ * modification, are permitted provided that the following conditions
++ * are met:
++ * 1. Redistributions of source code must retain the above copyright
++ * notice, this list of conditions, and the following disclaimer,
++ * without modification.
++ * 2. 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.
++ * 3. The names of the above-listed copyright holders may not be used
++ * to endorse or promote products derived from this software without
++ * specific prior written permission.
++ *
++ * ALTERNATIVELY, this software may be distributed under the terms of the
++ * GNU General Public License ("GPL") version 2, as published by the Free
++ * Software Foundation.
++ *
++ * 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 OWNER 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 <linux/kernel.h>
++#include <linux/module.h>
++#include <linux/kthread.h>
++#include <linux/fs.h>
++#include <linux/device.h>
++#include <linux/cdev.h>
++#include <linux/mm.h>
++#include <linux/proc_fs.h>
++#include <linux/seq_file.h>
++#include <linux/dma-mapping.h>
++#include <linux/dma-contiguous.h>
++#include <linux/platform_device.h>
++#include <linux/uaccess.h>
++#include <asm/cacheflush.h>
++
++#include "vc_cma.h"
++
++#include "vchiq_util.h"
++#include "vchiq_connected.h"
++//#include "debug_sym.h"
++//#include "vc_mem.h"
++
++#define DRIVER_NAME "vc-cma"
++
++#define LOG_DBG(fmt, ...) \
++ if (vc_cma_debug) \
++ printk(KERN_INFO fmt "\n", ##__VA_ARGS__)
++#define LOG_INFO(fmt, ...) \
++ printk(KERN_INFO fmt "\n", ##__VA_ARGS__)
++#define LOG_ERR(fmt, ...) \
++ printk(KERN_ERR fmt "\n", ##__VA_ARGS__)
++
++#define VC_CMA_FOURCC VCHIQ_MAKE_FOURCC('C', 'M', 'A', ' ')
++#define VC_CMA_VERSION 2
++
++#define VC_CMA_CHUNK_ORDER 6 /* 256K */
++#define VC_CMA_CHUNK_SIZE (4096 << VC_CMA_CHUNK_ORDER)
++#define VC_CMA_MAX_PARAMS_PER_MSG \
++ ((VCHIQ_MAX_MSG_SIZE - sizeof(unsigned short))/sizeof(unsigned short))
++#define VC_CMA_RESERVE_COUNT_MAX 16
++
++#define PAGES_PER_CHUNK (VC_CMA_CHUNK_SIZE / PAGE_SIZE)
++
++#define VCADDR_TO_PHYSADDR(vcaddr) (mm_vc_mem_phys_addr + vcaddr)
++
++#define loud_error(...) \
++ LOG_ERR("===== " __VA_ARGS__)
++
++enum {
++ VC_CMA_MSG_QUIT,
++ VC_CMA_MSG_OPEN,
++ VC_CMA_MSG_TICK,
++ VC_CMA_MSG_ALLOC, /* chunk count */
++ VC_CMA_MSG_FREE, /* chunk, chunk, ... */
++ VC_CMA_MSG_ALLOCATED, /* chunk, chunk, ... */
++ VC_CMA_MSG_REQUEST_ALLOC, /* chunk count */
++ VC_CMA_MSG_REQUEST_FREE, /* chunk count */
++ VC_CMA_MSG_RESERVE, /* bytes lo, bytes hi */
++ VC_CMA_MSG_UPDATE_RESERVE,
++ VC_CMA_MSG_MAX
++};
++
++struct cma_msg {
++ unsigned short type;
++ unsigned short params[VC_CMA_MAX_PARAMS_PER_MSG];
++};
++
++struct vc_cma_reserve_user {
++ unsigned int pid;
++ unsigned int reserve;
++};
++
++/* Device (/dev) related variables */
++static dev_t vc_cma_devnum;
++static struct class *vc_cma_class;
++static struct cdev vc_cma_cdev;
++static int vc_cma_inited;
++static int vc_cma_debug;
++
++/* Proc entry */
++static struct proc_dir_entry *vc_cma_proc_entry;
++
++phys_addr_t vc_cma_base;
++struct page *vc_cma_base_page;
++unsigned int vc_cma_size;
++EXPORT_SYMBOL(vc_cma_size);
++unsigned int vc_cma_initial;
++unsigned int vc_cma_chunks;
++unsigned int vc_cma_chunks_used;
++unsigned int vc_cma_chunks_reserved;
++
++
++void *vc_cma_dma_alloc;
++unsigned int vc_cma_dma_size;
++
++static int in_loud_error;
++
++unsigned int vc_cma_reserve_total;
++unsigned int vc_cma_reserve_count;
++struct vc_cma_reserve_user vc_cma_reserve_users[VC_CMA_RESERVE_COUNT_MAX];
++static DEFINE_SEMAPHORE(vc_cma_reserve_mutex);
++static DEFINE_SEMAPHORE(vc_cma_worker_queue_push_mutex);
++
++static u64 vc_cma_dma_mask = DMA_BIT_MASK(32);
++static struct platform_device vc_cma_device = {
++ .name = "vc-cma",
++ .id = 0,
++ .dev = {
++ .dma_mask = &vc_cma_dma_mask,
++ .coherent_dma_mask = DMA_BIT_MASK(32),
++ },
++};
++
++static VCHIQ_INSTANCE_T cma_instance;
++static VCHIQ_SERVICE_HANDLE_T cma_service;
++static VCHIU_QUEUE_T cma_msg_queue;
++static struct task_struct *cma_worker;
++
++static int vc_cma_set_reserve(unsigned int reserve, unsigned int pid);
++static int vc_cma_alloc_chunks(int num_chunks, struct cma_msg *reply);
++static VCHIQ_STATUS_T cma_service_callback(VCHIQ_REASON_T reason,
++ VCHIQ_HEADER_T * header,
++ VCHIQ_SERVICE_HANDLE_T service,
++ void *bulk_userdata);
++static void send_vc_msg(unsigned short type,
++ unsigned short param1, unsigned short param2);
++static bool send_worker_msg(VCHIQ_HEADER_T * msg);
++
++static int early_vc_cma_mem(char *p)
++{
++ unsigned int new_size;
++ printk(KERN_NOTICE "early_vc_cma_mem(%s)", p);
++ vc_cma_size = memparse(p, &p);
++ vc_cma_initial = vc_cma_size;
++ if (*p == '/')
++ vc_cma_size = memparse(p + 1, &p);
++ if (*p == '@')
++ vc_cma_base = memparse(p + 1, &p);
++
++ new_size = (vc_cma_size - ((-vc_cma_base) & (VC_CMA_CHUNK_SIZE - 1)))
++ & ~(VC_CMA_CHUNK_SIZE - 1);
++ if (new_size > vc_cma_size)
++ vc_cma_size = 0;
++ vc_cma_initial = (vc_cma_initial + VC_CMA_CHUNK_SIZE - 1)
++ & ~(VC_CMA_CHUNK_SIZE - 1);
++ if (vc_cma_initial > vc_cma_size)
++ vc_cma_initial = vc_cma_size;
++ vc_cma_base = (vc_cma_base + VC_CMA_CHUNK_SIZE - 1)
++ & ~(VC_CMA_CHUNK_SIZE - 1);
++
++ printk(KERN_NOTICE " -> initial %x, size %x, base %x", vc_cma_initial,
++ vc_cma_size, (unsigned int)vc_cma_base);
++
++ return 0;
++}
++
++early_param("vc-cma-mem", early_vc_cma_mem);
++
++void __init vc_cma_early_init(void)
++{
++ LOG_DBG("vc_cma_early_init - vc_cma_chunks = %d", vc_cma_chunks);
++ if (vc_cma_size) {
++ int rc = platform_device_register(&vc_cma_device);
++ LOG_DBG("platform_device_register -> %d", rc);
++ }
++}
++
++void __init vc_cma_reserve(void)
++{
++ /* if vc_cma_size is set, then declare vc CMA area of the same
++ * size from the end of memory
++ */
++ if (vc_cma_size) {
++ if (dma_declare_contiguous(&vc_cma_device.dev, vc_cma_size,
++ vc_cma_base, 0) == 0) {
++ if (!dev_get_cma_area(NULL)) {
++ /* There is no default CMA area - make this
++ the default */
++ struct cma *vc_cma_area = dev_get_cma_area(
++ &vc_cma_device.dev);
++ dma_contiguous_set_default(vc_cma_area);
++ LOG_INFO("vc_cma_reserve - using vc_cma as "
++ "the default contiguous DMA area");
++ }
++ } else {
++ LOG_ERR("vc_cma: dma_declare_contiguous(%x,%x) failed",
++ vc_cma_size, (unsigned int)vc_cma_base);
++ vc_cma_size = 0;
++ }
++ }
++ vc_cma_chunks = vc_cma_size / VC_CMA_CHUNK_SIZE;
++}
++
++/****************************************************************************
++*
++* vc_cma_open
++*
++***************************************************************************/
++
++static int vc_cma_open(struct inode *inode, struct file *file)
++{
++ (void)inode;
++ (void)file;
++
++ return 0;
++}
++
++/****************************************************************************
++*
++* vc_cma_release
++*
++***************************************************************************/
++
++static int vc_cma_release(struct inode *inode, struct file *file)
++{
++ (void)inode;
++ (void)file;
++
++ vc_cma_set_reserve(0, current->tgid);
++
++ return 0;
++}
++
++/****************************************************************************
++*
++* vc_cma_ioctl
++*
++***************************************************************************/
++
++static long vc_cma_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
++{
++ int rc = 0;
++
++ (void)cmd;
++ (void)arg;
++
++ switch (cmd) {
++ case VC_CMA_IOC_RESERVE:
++ rc = vc_cma_set_reserve((unsigned int)arg, current->tgid);
++ if (rc >= 0)
++ rc = 0;
++ break;
++ default:
++ LOG_ERR("vc-cma: Unknown ioctl %x", cmd);
++ return -ENOTTY;
++ }
++
++ return rc;
++}
++
++/****************************************************************************
++*
++* File Operations for the driver.
++*
++***************************************************************************/
++
++static const struct file_operations vc_cma_fops = {
++ .owner = THIS_MODULE,
++ .open = vc_cma_open,
++ .release = vc_cma_release,
++ .unlocked_ioctl = vc_cma_ioctl,
++};
++
++/****************************************************************************
++*
++* vc_cma_proc_open
++*
++***************************************************************************/
++
++static int vc_cma_show_info(struct seq_file *m, void *v)
++{
++ int i;
++
++ seq_printf(m, "Videocore CMA:\n");
++ seq_printf(m, " Base : %08x\n", (unsigned int)vc_cma_base);
++ seq_printf(m, " Length : %08x\n", vc_cma_size);
++ seq_printf(m, " Initial : %08x\n", vc_cma_initial);
++ seq_printf(m, " Chunk size : %08x\n", VC_CMA_CHUNK_SIZE);
++ seq_printf(m, " Chunks : %4d (%d bytes)\n",
++ (int)vc_cma_chunks,
++ (int)(vc_cma_chunks * VC_CMA_CHUNK_SIZE));
++ seq_printf(m, " Used : %4d (%d bytes)\n",
++ (int)vc_cma_chunks_used,
++ (int)(vc_cma_chunks_used * VC_CMA_CHUNK_SIZE));
++ seq_printf(m, " Reserved : %4d (%d bytes)\n",
++ (unsigned int)vc_cma_chunks_reserved,
++ (int)(vc_cma_chunks_reserved * VC_CMA_CHUNK_SIZE));
++
++ for (i = 0; i < vc_cma_reserve_count; i++) {
++ struct vc_cma_reserve_user *user = &vc_cma_reserve_users[i];
++ seq_printf(m, " PID %5d: %d bytes\n", user->pid,
++ user->reserve);
++ }
++ seq_printf(m, " dma_alloc : %p (%d pages)\n",
++ vc_cma_dma_alloc ? page_address(vc_cma_dma_alloc) : 0,
++ vc_cma_dma_size);
++
++ seq_printf(m, "\n");
++
++ return 0;
++}
++
++static int vc_cma_proc_open(struct inode *inode, struct file *file)
++{
++ return single_open(file, vc_cma_show_info, NULL);
++}
++
++/****************************************************************************
++*
++* vc_cma_proc_write
++*
++***************************************************************************/
++
++static int vc_cma_proc_write(struct file *file,
++ const char __user *buffer,
++ size_t size, loff_t *ppos)
++{
++ int rc = -EFAULT;
++ char input_str[20];
++
++ memset(input_str, 0, sizeof(input_str));
++
++ if (size > sizeof(input_str)) {
++ LOG_ERR("%s: input string length too long", __func__);
++ goto out;
++ }
++
++ if (copy_from_user(input_str, buffer, size - 1)) {
++ LOG_ERR("%s: failed to get input string", __func__);
++ goto out;
++ }
++#define ALLOC_STR "alloc"
++#define FREE_STR "free"
++#define DEBUG_STR "debug"
++#define RESERVE_STR "reserve"
++#define DMA_ALLOC_STR "dma_alloc"
++#define DMA_FREE_STR "dma_free"
++ if (strncmp(input_str, ALLOC_STR, strlen(ALLOC_STR)) == 0) {
++ int alloc_size;
++ char *p = input_str + strlen(ALLOC_STR);
++
++ while (*p == ' ')
++ p++;
++ alloc_size = memparse(p, NULL);
++ LOG_INFO("/proc/vc-cma: alloc %d", alloc_size);
++ if (alloc_size)
++ send_vc_msg(VC_CMA_MSG_REQUEST_FREE,
++ alloc_size / VC_CMA_CHUNK_SIZE, 0);
++ else
++ LOG_ERR("invalid size '%s'", p);
++ rc = size;
++ } else if (strncmp(input_str, FREE_STR, strlen(FREE_STR)) == 0) {
++ int alloc_size;
++ char *p = input_str + strlen(FREE_STR);
++
++ while (*p == ' ')
++ p++;
++ alloc_size = memparse(p, NULL);
++ LOG_INFO("/proc/vc-cma: free %d", alloc_size);
++ if (alloc_size)
++ send_vc_msg(VC_CMA_MSG_REQUEST_ALLOC,
++ alloc_size / VC_CMA_CHUNK_SIZE, 0);
++ else
++ LOG_ERR("invalid size '%s'", p);
++ rc = size;
++ } else if (strncmp(input_str, DEBUG_STR, strlen(DEBUG_STR)) == 0) {
++ char *p = input_str + strlen(DEBUG_STR);
++ while (*p == ' ')
++ p++;
++ if ((strcmp(p, "on") == 0) || (strcmp(p, "1") == 0))
++ vc_cma_debug = 1;
++ else if ((strcmp(p, "off") == 0) || (strcmp(p, "0") == 0))
++ vc_cma_debug = 0;
++ LOG_INFO("/proc/vc-cma: debug %s", vc_cma_debug ? "on" : "off");
++ rc = size;
++ } else if (strncmp(input_str, RESERVE_STR, strlen(RESERVE_STR)) == 0) {
++ int alloc_size;
++ int reserved;
++ char *p = input_str + strlen(RESERVE_STR);
++ while (*p == ' ')
++ p++;
++ alloc_size = memparse(p, NULL);
++
++ reserved = vc_cma_set_reserve(alloc_size, current->tgid);
++ rc = (reserved >= 0) ? size : reserved;
++ } else if (strncmp(input_str, DMA_ALLOC_STR, strlen(DMA_ALLOC_STR)) == 0) {
++ int alloc_size;
++ char *p = input_str + strlen(DMA_ALLOC_STR);
++ while (*p == ' ')
++ p++;
++ alloc_size = memparse(p, NULL);
++
++ if (vc_cma_dma_alloc) {
++ dma_release_from_contiguous(NULL, vc_cma_dma_alloc,
++ vc_cma_dma_size);
++ vc_cma_dma_alloc = NULL;
++ vc_cma_dma_size = 0;
++ }
++ vc_cma_dma_alloc = dma_alloc_from_contiguous(NULL, alloc_size, 0);
++ vc_cma_dma_size = (vc_cma_dma_alloc ? alloc_size : 0);
++ if (vc_cma_dma_alloc)
++ LOG_INFO("dma_alloc(%d pages) -> %p", alloc_size, page_address(vc_cma_dma_alloc));
++ else
++ LOG_ERR("dma_alloc(%d pages) failed", alloc_size);
++ rc = size;
++ } else if (strncmp(input_str, DMA_FREE_STR, strlen(DMA_FREE_STR)) == 0) {
++ if (vc_cma_dma_alloc) {
++ dma_release_from_contiguous(NULL, vc_cma_dma_alloc,
++ vc_cma_dma_size);
++ vc_cma_dma_alloc = NULL;
++ vc_cma_dma_size = 0;
++ }
++ rc = size;
++ }
++
++out:
++ return rc;
++}
++
++/****************************************************************************
++*
++* File Operations for /proc interface.
++*
++***************************************************************************/
++
++static const struct file_operations vc_cma_proc_fops = {
++ .open = vc_cma_proc_open,
++ .read = seq_read,
++ .write = vc_cma_proc_write,
++ .llseek = seq_lseek,
++ .release = single_release
++};
++
++static int vc_cma_set_reserve(unsigned int reserve, unsigned int pid)
++{
++ struct vc_cma_reserve_user *user = NULL;
++ int delta = 0;
++ int i;
++
++ if (down_interruptible(&vc_cma_reserve_mutex))
++ return -ERESTARTSYS;
++
++ for (i = 0; i < vc_cma_reserve_count; i++) {
++ if (pid == vc_cma_reserve_users[i].pid) {
++ user = &vc_cma_reserve_users[i];
++ delta = reserve - user->reserve;
++ if (reserve)
++ user->reserve = reserve;
++ else {
++ /* Remove this entry by copying downwards */
++ while ((i + 1) < vc_cma_reserve_count) {
++ user[0].pid = user[1].pid;
++ user[0].reserve = user[1].reserve;
++ user++;
++ i++;
++ }
++ vc_cma_reserve_count--;
++ user = NULL;
++ }
++ break;
++ }
++ }
++
++ if (reserve && !user) {
++ if (vc_cma_reserve_count == VC_CMA_RESERVE_COUNT_MAX) {
++ LOG_ERR("vc-cma: Too many reservations - "
++ "increase CMA_RESERVE_COUNT_MAX");
++ up(&vc_cma_reserve_mutex);
++ return -EBUSY;
++ }
++ user = &vc_cma_reserve_users[vc_cma_reserve_count];
++ user->pid = pid;
++ user->reserve = reserve;
++ delta = reserve;
++ vc_cma_reserve_count++;
++ }
++
++ vc_cma_reserve_total += delta;
++
++ send_vc_msg(VC_CMA_MSG_RESERVE,
++ vc_cma_reserve_total & 0xffff, vc_cma_reserve_total >> 16);
++
++ send_worker_msg((VCHIQ_HEADER_T *) VC_CMA_MSG_UPDATE_RESERVE);
++
++ LOG_DBG("/proc/vc-cma: reserve %d (PID %d) - total %u",
++ reserve, pid, vc_cma_reserve_total);
++
++ up(&vc_cma_reserve_mutex);
++
++ return vc_cma_reserve_total;
++}
++
++static VCHIQ_STATUS_T cma_service_callback(VCHIQ_REASON_T reason,
++ VCHIQ_HEADER_T * header,
++ VCHIQ_SERVICE_HANDLE_T service,
++ void *bulk_userdata)
++{
++ switch (reason) {
++ case VCHIQ_MESSAGE_AVAILABLE:
++ if (!send_worker_msg(header))
++ return VCHIQ_RETRY;
++ break;
++ case VCHIQ_SERVICE_CLOSED:
++ LOG_DBG("CMA service closed");
++ break;
++ default:
++ LOG_ERR("Unexpected CMA callback reason %d", reason);
++ break;
++ }
++ return VCHIQ_SUCCESS;
++}
++
++static void send_vc_msg(unsigned short type,
++ unsigned short param1, unsigned short param2)
++{
++ unsigned short msg[] = { type, param1, param2 };
++ VCHIQ_ELEMENT_T elem = { &msg, sizeof(msg) };
++ VCHIQ_STATUS_T ret;
++ vchiq_use_service(cma_service);
++ ret = vchiq_queue_message(cma_service, &elem, 1);
++ vchiq_release_service(cma_service);
++ if (ret != VCHIQ_SUCCESS)
++ LOG_ERR("vchiq_queue_message returned %x", ret);
++}
++
++static bool send_worker_msg(VCHIQ_HEADER_T * msg)
++{
++ if (down_interruptible(&vc_cma_worker_queue_push_mutex))
++ return false;
++ vchiu_queue_push(&cma_msg_queue, msg);
++ up(&vc_cma_worker_queue_push_mutex);
++ return true;
++}
++
++static int vc_cma_alloc_chunks(int num_chunks, struct cma_msg *reply)
++{
++ int i;
++ for (i = 0; i < num_chunks; i++) {
++ struct page *chunk;
++ unsigned int chunk_num;
++ uint8_t *chunk_addr;
++ size_t chunk_size = PAGES_PER_CHUNK << PAGE_SHIFT;
++
++ chunk = dma_alloc_from_contiguous(&vc_cma_device.dev,
++ PAGES_PER_CHUNK,
++ VC_CMA_CHUNK_ORDER);
++ if (!chunk)
++ break;
++
++ chunk_addr = page_address(chunk);
++ dmac_flush_range(chunk_addr, chunk_addr + chunk_size);
++ outer_inv_range(__pa(chunk_addr), __pa(chunk_addr) +
++ chunk_size);
++
++ chunk_num =
++ (page_to_phys(chunk) - vc_cma_base) / VC_CMA_CHUNK_SIZE;
++ BUG_ON(((page_to_phys(chunk) - vc_cma_base) %
++ VC_CMA_CHUNK_SIZE) != 0);
++ if (chunk_num >= vc_cma_chunks) {
++ phys_addr_t _pa = vc_cma_base + vc_cma_size - 1;
++ LOG_ERR("%s: ===============================",
++ __func__);
++ LOG_ERR("%s: chunk phys %x, vc_cma %pa-%pa - "
++ "bad SPARSEMEM configuration?",
++ __func__, (unsigned int)page_to_phys(chunk),
++ &vc_cma_base, &_pa);
++ LOG_ERR("%s: dev->cma_area = %p", __func__,
++ (void*)0/*vc_cma_device.dev.cma_area*/);
++ LOG_ERR("%s: ===============================",
++ __func__);
++ break;
++ }
++ reply->params[i] = chunk_num;
++ vc_cma_chunks_used++;
++ }
++
++ if (i < num_chunks) {
++ LOG_ERR("%s: dma_alloc_from_contiguous failed "
++ "for %x bytes (alloc %d of %d, %d free)",
++ __func__, VC_CMA_CHUNK_SIZE, i,
++ num_chunks, vc_cma_chunks - vc_cma_chunks_used);
++ num_chunks = i;
++ }
++
++ LOG_DBG("CMA allocated %d chunks -> %d used",
++ num_chunks, vc_cma_chunks_used);
++ reply->type = VC_CMA_MSG_ALLOCATED;
++
++ {
++ VCHIQ_ELEMENT_T elem = {
++ reply,
++ offsetof(struct cma_msg, params[0]) +
++ num_chunks * sizeof(reply->params[0])
++ };
++ VCHIQ_STATUS_T ret;
++ vchiq_use_service(cma_service);
++ ret = vchiq_queue_message(cma_service, &elem, 1);
++ vchiq_release_service(cma_service);
++ if (ret != VCHIQ_SUCCESS)
++ LOG_ERR("vchiq_queue_message return " "%x", ret);
++ }
++
++ return num_chunks;
++}
++
++static int cma_worker_proc(void *param)
++{
++ static struct cma_msg reply;
++ (void)param;
++
++ while (1) {
++ VCHIQ_HEADER_T *msg;
++ static struct cma_msg msg_copy;
++ struct cma_msg *cma_msg = &msg_copy;
++ int type, msg_size;
++
++ msg = vchiu_queue_pop(&cma_msg_queue);
++ if ((unsigned int)msg >= VC_CMA_MSG_MAX) {
++ msg_size = msg->size;
++ memcpy(&msg_copy, msg->data, msg_size);
++ type = cma_msg->type;
++ vchiq_release_message(cma_service, msg);
++ } else {
++ msg_size = 0;
++ type = (int)msg;
++ if (type == VC_CMA_MSG_QUIT)
++ break;
++ else if (type == VC_CMA_MSG_UPDATE_RESERVE) {
++ msg = NULL;
++ cma_msg = NULL;
++ } else {
++ BUG();
++ continue;
++ }
++ }
++
++ switch (type) {
++ case VC_CMA_MSG_ALLOC:{
++ int num_chunks, free_chunks;
++ num_chunks = cma_msg->params[0];
++ free_chunks =
++ vc_cma_chunks - vc_cma_chunks_used;
++ LOG_DBG("CMA_MSG_ALLOC(%d chunks)", num_chunks);
++ if (num_chunks > VC_CMA_MAX_PARAMS_PER_MSG) {
++ LOG_ERR
++ ("CMA_MSG_ALLOC - chunk count (%d) "
++ "exceeds VC_CMA_MAX_PARAMS_PER_MSG (%d)",
++ num_chunks,
++ VC_CMA_MAX_PARAMS_PER_MSG);
++ num_chunks = VC_CMA_MAX_PARAMS_PER_MSG;
++ }
++
++ if (num_chunks > free_chunks) {
++ LOG_ERR
++ ("CMA_MSG_ALLOC - chunk count (%d) "
++ "exceeds free chunks (%d)",
++ num_chunks, free_chunks);
++ num_chunks = free_chunks;
++ }
++
++ vc_cma_alloc_chunks(num_chunks, &reply);
++ }
++ break;
++
++ case VC_CMA_MSG_FREE:{
++ int chunk_count =
++ (msg_size -
++ offsetof(struct cma_msg,
++ params)) /
++ sizeof(cma_msg->params[0]);
++ int i;
++ BUG_ON(chunk_count <= 0);
++
++ LOG_DBG("CMA_MSG_FREE(%d chunks - %x, ...)",
++ chunk_count, cma_msg->params[0]);
++ for (i = 0; i < chunk_count; i++) {
++ int chunk_num = cma_msg->params[i];
++ struct page *page = vc_cma_base_page +
++ chunk_num * PAGES_PER_CHUNK;
++ if (chunk_num >= vc_cma_chunks) {
++ LOG_ERR
++ ("CMA_MSG_FREE - chunk %d of %d"
++ " (value %x) exceeds maximum "
++ "(%x)", i, chunk_count,
++ chunk_num,
++ vc_cma_chunks - 1);
++ break;
++ }
++
++ if (!dma_release_from_contiguous
++ (&vc_cma_device.dev, page,
++ PAGES_PER_CHUNK)) {
++ phys_addr_t _pa = page_to_phys(page);
++ LOG_ERR
++ ("CMA_MSG_FREE - failed to "
++ "release chunk %d (phys %pa, "
++ "page %x)", chunk_num,
++ &_pa,
++ (unsigned int)page);
++ }
++ vc_cma_chunks_used--;
++ }
++ LOG_DBG("CMA released %d chunks -> %d used",
++ i, vc_cma_chunks_used);
++ }
++ break;
++
++ case VC_CMA_MSG_UPDATE_RESERVE:{
++ int chunks_needed =
++ ((vc_cma_reserve_total + VC_CMA_CHUNK_SIZE -
++ 1)
++ / VC_CMA_CHUNK_SIZE) -
++ vc_cma_chunks_reserved;
++
++ LOG_DBG
++ ("CMA_MSG_UPDATE_RESERVE(%d chunks needed)",
++ chunks_needed);
++
++ /* Cap the reservations to what is available */
++ if (chunks_needed > 0) {
++ if (chunks_needed >
++ (vc_cma_chunks -
++ vc_cma_chunks_used))
++ chunks_needed =
++ (vc_cma_chunks -
++ vc_cma_chunks_used);
++
++ chunks_needed =
++ vc_cma_alloc_chunks(chunks_needed,
++ &reply);
++ }
++
++ LOG_DBG
++ ("CMA_MSG_UPDATE_RESERVE(%d chunks allocated)",
++ chunks_needed);
++ vc_cma_chunks_reserved += chunks_needed;
++ }
++ break;
++
++ default:
++ LOG_ERR("unexpected msg type %d", type);
++ break;
++ }
++ }
++
++ LOG_DBG("quitting...");
++ return 0;
++}
++
++/****************************************************************************
++*
++* vc_cma_connected_init
++*
++* This function is called once the videocore has been connected.
++*
++***************************************************************************/
++
++static void vc_cma_connected_init(void)
++{
++ VCHIQ_SERVICE_PARAMS_T service_params;
++
++ LOG_DBG("vc_cma_connected_init");
++
++ if (!vchiu_queue_init(&cma_msg_queue, 16)) {
++ LOG_ERR("could not create CMA msg queue");
++ goto fail_queue;
++ }
++
++ if (vchiq_initialise(&cma_instance) != VCHIQ_SUCCESS)
++ goto fail_vchiq_init;
++
++ vchiq_connect(cma_instance);
++
++ service_params.fourcc = VC_CMA_FOURCC;
++ service_params.callback = cma_service_callback;
++ service_params.userdata = NULL;
++ service_params.version = VC_CMA_VERSION;
++ service_params.version_min = VC_CMA_VERSION;
++
++ if (vchiq_open_service(cma_instance, &service_params,
++ &cma_service) != VCHIQ_SUCCESS) {
++ LOG_ERR("failed to open service - already in use?");
++ goto fail_vchiq_open;
++ }
++
++ vchiq_release_service(cma_service);
++
++ cma_worker = kthread_create(cma_worker_proc, NULL, "cma_worker");
++ if (!cma_worker) {
++ LOG_ERR("could not create CMA worker thread");
++ goto fail_worker;
++ }
++ set_user_nice(cma_worker, -20);
++ wake_up_process(cma_worker);
++
++ return;
++
++fail_worker:
++ vchiq_close_service(cma_service);
++fail_vchiq_open:
++ vchiq_shutdown(cma_instance);
++fail_vchiq_init:
++ vchiu_queue_delete(&cma_msg_queue);
++fail_queue:
++ return;
++}
++
++void
++loud_error_header(void)
++{
++ if (in_loud_error)
++ return;
++
++ LOG_ERR("============================================================"
++ "================");
++ LOG_ERR("============================================================"
++ "================");
++ LOG_ERR("=====");
++
++ in_loud_error = 1;
++}
++
++void
++loud_error_footer(void)
++{
++ if (!in_loud_error)
++ return;
++
++ LOG_ERR("=====");
++ LOG_ERR("============================================================"
++ "================");
++ LOG_ERR("============================================================"
++ "================");
++
++ in_loud_error = 0;
++}
++
++#if 1
++static int check_cma_config(void) { return 1; }
++#else
++static int
++read_vc_debug_var(VC_MEM_ACCESS_HANDLE_T handle,
++ const char *symbol,
++ void *buf, size_t bufsize)
++{
++ VC_MEM_ADDR_T vcMemAddr;
++ size_t vcMemSize;
++ uint8_t *mapAddr;
++ off_t vcMapAddr;
++
++ if (!LookupVideoCoreSymbol(handle, symbol,
++ &vcMemAddr,
++ &vcMemSize)) {
++ loud_error_header();
++ loud_error(
++ "failed to find VC symbol \"%s\".",
++ symbol);
++ loud_error_footer();
++ return 0;
++ }
++
++ if (vcMemSize != bufsize) {
++ loud_error_header();
++ loud_error(
++ "VC symbol \"%s\" is the wrong size.",
++ symbol);
++ loud_error_footer();
++ return 0;
++ }
++
++ vcMapAddr = (off_t)vcMemAddr & VC_MEM_TO_ARM_ADDR_MASK;
++ vcMapAddr += mm_vc_mem_phys_addr;
++ mapAddr = ioremap_nocache(vcMapAddr, vcMemSize);
++ if (mapAddr == 0) {
++ loud_error_header();
++ loud_error(
++ "failed to ioremap \"%s\" @ 0x%x "
++ "(phys: 0x%x, size: %u).",
++ symbol,
++ (unsigned int)vcMapAddr,
++ (unsigned int)vcMemAddr,
++ (unsigned int)vcMemSize);
++ loud_error_footer();
++ return 0;
++ }
++
++ memcpy(buf, mapAddr, bufsize);
++ iounmap(mapAddr);
++
++ return 1;
++}
++
++
++static int
++check_cma_config(void)
++{
++ VC_MEM_ACCESS_HANDLE_T mem_hndl;
++ VC_MEM_ADDR_T mempool_start;
++ VC_MEM_ADDR_T mempool_end;
++ VC_MEM_ADDR_T mempool_offline_start;
++ VC_MEM_ADDR_T mempool_offline_end;
++ VC_MEM_ADDR_T cam_alloc_base;
++ VC_MEM_ADDR_T cam_alloc_size;
++ VC_MEM_ADDR_T cam_alloc_end;
++ int success = 0;
++
++ if (OpenVideoCoreMemory(&mem_hndl) != 0)
++ goto out;
++
++ /* Read the relevant VideoCore variables */
++ if (!read_vc_debug_var(mem_hndl, "__MEMPOOL_START",
++ &mempool_start,
++ sizeof(mempool_start)))
++ goto close;
++
++ if (!read_vc_debug_var(mem_hndl, "__MEMPOOL_END",
++ &mempool_end,
++ sizeof(mempool_end)))
++ goto close;
++
++ if (!read_vc_debug_var(mem_hndl, "__MEMPOOL_OFFLINE_START",
++ &mempool_offline_start,
++ sizeof(mempool_offline_start)))
++ goto close;
++
++ if (!read_vc_debug_var(mem_hndl, "__MEMPOOL_OFFLINE_END",
++ &mempool_offline_end,
++ sizeof(mempool_offline_end)))
++ goto close;
++
++ if (!read_vc_debug_var(mem_hndl, "cam_alloc_base",
++ &cam_alloc_base,
++ sizeof(cam_alloc_base)))
++ goto close;
++
++ if (!read_vc_debug_var(mem_hndl, "cam_alloc_size",
++ &cam_alloc_size,
++ sizeof(cam_alloc_size)))
++ goto close;
++
++ cam_alloc_end = cam_alloc_base + cam_alloc_size;
++
++ success = 1;
++
++ /* Now the sanity checks */
++ if (!mempool_offline_start)
++ mempool_offline_start = mempool_start;
++ if (!mempool_offline_end)
++ mempool_offline_end = mempool_end;
++
++ if (VCADDR_TO_PHYSADDR(mempool_offline_start) != vc_cma_base) {
++ loud_error_header();
++ loud_error(
++ "__MEMPOOL_OFFLINE_START(%x -> %lx) doesn't match "
++ "vc_cma_base(%x)",
++ mempool_offline_start,
++ VCADDR_TO_PHYSADDR(mempool_offline_start),
++ vc_cma_base);
++ success = 0;
++ }
++
++ if (VCADDR_TO_PHYSADDR(mempool_offline_end) !=
++ (vc_cma_base + vc_cma_size)) {
++ loud_error_header();
++ loud_error(
++ "__MEMPOOL_OFFLINE_END(%x -> %lx) doesn't match "
++ "vc_cma_base(%x) + vc_cma_size(%x) = %x",
++ mempool_offline_start,
++ VCADDR_TO_PHYSADDR(mempool_offline_end),
++ vc_cma_base, vc_cma_size, vc_cma_base + vc_cma_size);
++ success = 0;
++ }
++
++ if (mempool_end < mempool_start) {
++ loud_error_header();
++ loud_error(
++ "__MEMPOOL_END(%x) must not be before "
++ "__MEMPOOL_START(%x)",
++ mempool_end,
++ mempool_start);
++ success = 0;
++ }
++
++ if (mempool_offline_end < mempool_offline_start) {
++ loud_error_header();
++ loud_error(
++ "__MEMPOOL_OFFLINE_END(%x) must not be before "
++ "__MEMPOOL_OFFLINE_START(%x)",
++ mempool_offline_end,
++ mempool_offline_start);
++ success = 0;
++ }
++
++ if (mempool_offline_start < mempool_start) {
++ loud_error_header();
++ loud_error(
++ "__MEMPOOL_OFFLINE_START(%x) must not be before "
++ "__MEMPOOL_START(%x)",
++ mempool_offline_start,
++ mempool_start);
++ success = 0;
++ }
++
++ if (mempool_offline_end > mempool_end) {
++ loud_error_header();
++ loud_error(
++ "__MEMPOOL_OFFLINE_END(%x) must not be after "
++ "__MEMPOOL_END(%x)",
++ mempool_offline_end,
++ mempool_end);
++ success = 0;
++ }
++
++ if ((cam_alloc_base < mempool_end) &&
++ (cam_alloc_end > mempool_start)) {
++ loud_error_header();
++ loud_error(
++ "cam_alloc pool(%x-%x) overlaps "
++ "mempool(%x-%x)",
++ cam_alloc_base, cam_alloc_end,
++ mempool_start, mempool_end);
++ success = 0;
++ }
++
++ loud_error_footer();
++
++close:
++ CloseVideoCoreMemory(mem_hndl);
++
++out:
++ return success;
++}
++#endif
++
++static int vc_cma_init(void)
++{
++ int rc = -EFAULT;
++ struct device *dev;
++
++ if (!check_cma_config())
++ goto out_release;
++
++ LOG_INFO("vc-cma: Videocore CMA driver");
++ LOG_INFO("vc-cma: vc_cma_base = %pa", &vc_cma_base);
++ LOG_INFO("vc-cma: vc_cma_size = 0x%08x (%u MiB)",
++ vc_cma_size, vc_cma_size / (1024 * 1024));
++ LOG_INFO("vc-cma: vc_cma_initial = 0x%08x (%u MiB)",
++ vc_cma_initial, vc_cma_initial / (1024 * 1024));
++
++ vc_cma_base_page = phys_to_page(vc_cma_base);
++
++ if (vc_cma_chunks) {
++ int chunks_needed = vc_cma_initial / VC_CMA_CHUNK_SIZE;
++
++ for (vc_cma_chunks_used = 0;
++ vc_cma_chunks_used < chunks_needed; vc_cma_chunks_used++) {
++ struct page *chunk;
++ chunk = dma_alloc_from_contiguous(&vc_cma_device.dev,
++ PAGES_PER_CHUNK,
++ VC_CMA_CHUNK_ORDER);
++ if (!chunk)
++ break;
++ BUG_ON(((page_to_phys(chunk) - vc_cma_base) %
++ VC_CMA_CHUNK_SIZE) != 0);
++ }
++ if (vc_cma_chunks_used != chunks_needed) {
++ LOG_ERR("%s: dma_alloc_from_contiguous failed (%d "
++ "bytes, allocation %d of %d)",
++ __func__, VC_CMA_CHUNK_SIZE,
++ vc_cma_chunks_used, chunks_needed);
++ goto out_release;
++ }
++
++ vchiq_add_connected_callback(vc_cma_connected_init);
++ }
++
++ rc = alloc_chrdev_region(&vc_cma_devnum, 0, 1, DRIVER_NAME);
++ if (rc < 0) {
++ LOG_ERR("%s: alloc_chrdev_region failed (rc=%d)", __func__, rc);
++ goto out_release;
++ }
++
++ cdev_init(&vc_cma_cdev, &vc_cma_fops);
++ rc = cdev_add(&vc_cma_cdev, vc_cma_devnum, 1);
++ if (rc != 0) {
++ LOG_ERR("%s: cdev_add failed (rc=%d)", __func__, rc);
++ goto out_unregister;
++ }
++
++ vc_cma_class = class_create(THIS_MODULE, DRIVER_NAME);
++ if (IS_ERR(vc_cma_class)) {
++ rc = PTR_ERR(vc_cma_class);
++ LOG_ERR("%s: class_create failed (rc=%d)", __func__, rc);
++ goto out_cdev_del;
++ }
++
++ dev = device_create(vc_cma_class, NULL, vc_cma_devnum, NULL,
++ DRIVER_NAME);
++ if (IS_ERR(dev)) {
++ rc = PTR_ERR(dev);
++ LOG_ERR("%s: device_create failed (rc=%d)", __func__, rc);
++ goto out_class_destroy;
++ }
++
++ vc_cma_proc_entry = proc_create(DRIVER_NAME, 0444, NULL, &vc_cma_proc_fops);
++ if (vc_cma_proc_entry == NULL) {
++ rc = -EFAULT;
++ LOG_ERR("%s: proc_create failed", __func__);
++ goto out_device_destroy;
++ }
++
++ vc_cma_inited = 1;
++ return 0;
++
++out_device_destroy:
++ device_destroy(vc_cma_class, vc_cma_devnum);
++
++out_class_destroy:
++ class_destroy(vc_cma_class);
++ vc_cma_class = NULL;
++
++out_cdev_del:
++ cdev_del(&vc_cma_cdev);
++
++out_unregister:
++ unregister_chrdev_region(vc_cma_devnum, 1);
++
++out_release:
++ /* It is tempting to try to clean up by calling
++ dma_release_from_contiguous for all allocated chunks, but it isn't
++ a very safe thing to do. If vc_cma_initial is non-zero it is because
++ VideoCore is already using that memory, so giving it back to Linux
++ is likely to be fatal.
++ */
++ return -1;
++}
++
++/****************************************************************************
++*
++* vc_cma_exit
++*
++***************************************************************************/
++
++static void __exit vc_cma_exit(void)
++{
++ LOG_DBG("%s: called", __func__);
++
++ if (vc_cma_inited) {
++ remove_proc_entry(DRIVER_NAME, NULL);
++ device_destroy(vc_cma_class, vc_cma_devnum);
++ class_destroy(vc_cma_class);
++ cdev_del(&vc_cma_cdev);
++ unregister_chrdev_region(vc_cma_devnum, 1);
++ }
++}
++
++module_init(vc_cma_init);
++module_exit(vc_cma_exit);
++MODULE_LICENSE("GPL");
++MODULE_AUTHOR("Broadcom Corporation");
+--- /dev/null
++++ b/include/linux/broadcom/vc_cma.h
+@@ -0,0 +1,36 @@
++/*****************************************************************************
++* Copyright 2012 Broadcom Corporation. All rights reserved.
++*
++* Unless you and Broadcom execute a separate written software license
++* agreement governing use of this software, this software is licensed to you
++* under the terms of the GNU General Public License version 2, available at
++* http://www.broadcom.com/licenses/GPLv2.php (the "GPL").
++*
++* Notwithstanding the above, under no circumstances may you combine this
++* software in any way with any other Broadcom software provided under a
++* license other than the GPL, without Broadcom's express prior written
++* consent.
++*****************************************************************************/
++
++#if !defined( VC_CMA_H )
++#define VC_CMA_H
++
++#include <linux/ioctl.h>
++
++#define VC_CMA_IOC_MAGIC 0xc5
++
++#define VC_CMA_IOC_RESERVE _IO(VC_CMA_IOC_MAGIC, 0)
++
++#ifdef __KERNEL__
++
++#ifdef CONFIG_BCM_VC_CMA
++void vc_cma_early_init(void);
++void vc_cma_reserve(void);
++#else
++static inline void vc_cma_early_init(void) { }
++static inline void vc_cma_reserve(void) { }
++#endif
++
++#endif
++
++#endif /* VC_CMA_H */