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authorRongrong Zou <zourongrong@gmail.com>2016-11-16 14:31:51 +0100
committerRongrong Zou <zourongrong@gmail.com>2016-11-17 08:26:24 +0100
commite4daebc77e7b34fc7442ff78a3c3410376f1bcba (patch)
tree5bccb1f9492c439f1e4d8b589f5754bdd011e5b5 /drivers/gpu/drm/hisilicon
parentdrm/hisilicon/hibmc: Add hisilicon hibmc drm master driver (diff)
downloadlinux-e4daebc77e7b34fc7442ff78a3c3410376f1bcba.tar.xz
linux-e4daebc77e7b34fc7442ff78a3c3410376f1bcba.zip
drm/hisilicon/hibmc: Add video memory management
Hibmc have 32m video memory which can be accessed through PCIe by host, we use ttm to manage these memory. Signed-off-by: Rongrong Zou <zourongrong@gmail.com> Reviewed-by: Sean Paul <seanpaul@chromium.org> Reviewed-by: Xinliang Liu <xinliang.liu@linaro.org> Acked-by: Sean Paul <seanpaul@chromium.org>
Diffstat (limited to 'drivers/gpu/drm/hisilicon')
-rw-r--r--drivers/gpu/drm/hisilicon/hibmc/Makefile2
-rw-r--r--drivers/gpu/drm/hisilicon/hibmc/hibmc_drm_drv.c14
-rw-r--r--drivers/gpu/drm/hisilicon/hibmc/hibmc_drm_drv.h41
-rw-r--r--drivers/gpu/drm/hisilicon/hibmc/hibmc_ttm.c485
4 files changed, 541 insertions, 1 deletions
diff --git a/drivers/gpu/drm/hisilicon/hibmc/Makefile b/drivers/gpu/drm/hisilicon/hibmc/Makefile
index 47962a06c2dc..19ed0ef01a3c 100644
--- a/drivers/gpu/drm/hisilicon/hibmc/Makefile
+++ b/drivers/gpu/drm/hisilicon/hibmc/Makefile
@@ -1,4 +1,4 @@
ccflags-y := -Iinclude/drm
-hibmc-drm-y := hibmc_drm_drv.o
+hibmc-drm-y := hibmc_drm_drv.o hibmc_ttm.o
obj-$(CONFIG_DRM_HISI_HIBMC) += hibmc-drm.o
diff --git a/drivers/gpu/drm/hisilicon/hibmc/hibmc_drm_drv.c b/drivers/gpu/drm/hisilicon/hibmc/hibmc_drm_drv.c
index 6d20580f89b8..521f69f0c5f1 100644
--- a/drivers/gpu/drm/hisilicon/hibmc/hibmc_drm_drv.c
+++ b/drivers/gpu/drm/hisilicon/hibmc/hibmc_drm_drv.c
@@ -28,6 +28,7 @@ static const struct file_operations hibmc_fops = {
.release = drm_release,
.unlocked_ioctl = drm_ioctl,
.compat_ioctl = drm_compat_ioctl,
+ .mmap = hibmc_mmap,
.poll = drm_poll,
.read = drm_read,
.llseek = no_llseek,
@@ -43,6 +44,7 @@ static void hibmc_disable_vblank(struct drm_device *dev, unsigned int pipe)
}
static struct drm_driver hibmc_driver = {
+ .driver_features = DRIVER_GEM,
.fops = &hibmc_fops,
.name = "hibmc",
.date = "20160828",
@@ -52,6 +54,10 @@ static struct drm_driver hibmc_driver = {
.get_vblank_counter = drm_vblank_no_hw_counter,
.enable_vblank = hibmc_enable_vblank,
.disable_vblank = hibmc_disable_vblank,
+ .gem_free_object_unlocked = hibmc_gem_free_object,
+ .dumb_create = hibmc_dumb_create,
+ .dumb_map_offset = hibmc_dumb_mmap_offset,
+ .dumb_destroy = drm_gem_dumb_destroy,
};
static int hibmc_pm_suspend(struct device *dev)
@@ -194,6 +200,10 @@ static int hibmc_hw_init(struct hibmc_drm_private *priv)
static int hibmc_unload(struct drm_device *dev)
{
+ struct hibmc_drm_private *priv = dev->dev_private;
+
+ hibmc_mm_fini(priv);
+ dev->dev_private = NULL;
return 0;
}
@@ -214,6 +224,10 @@ static int hibmc_load(struct drm_device *dev)
if (ret)
goto err;
+ ret = hibmc_mm_init(priv);
+ if (ret)
+ goto err;
+
return 0;
err:
diff --git a/drivers/gpu/drm/hisilicon/hibmc/hibmc_drm_drv.h b/drivers/gpu/drm/hisilicon/hibmc/hibmc_drm_drv.h
index 840cd5afbb30..dcd304d66c8f 100644
--- a/drivers/gpu/drm/hisilicon/hibmc/hibmc_drm_drv.h
+++ b/drivers/gpu/drm/hisilicon/hibmc/hibmc_drm_drv.h
@@ -20,6 +20,8 @@
#define HIBMC_DRM_DRV_H
#include <drm/drmP.h>
+#include <drm/drm_gem.h>
+#include <drm/ttm/ttm_bo_driver.h>
struct hibmc_drm_private {
/* hw */
@@ -31,11 +33,50 @@ struct hibmc_drm_private {
/* drm */
struct drm_device *dev;
+ /* ttm */
+ struct drm_global_reference mem_global_ref;
+ struct ttm_bo_global_ref bo_global_ref;
+ struct ttm_bo_device bdev;
+ bool initialized;
+
+ bool mm_inited;
+};
+
+struct hibmc_bo {
+ struct ttm_buffer_object bo;
+ struct ttm_placement placement;
+ struct ttm_bo_kmap_obj kmap;
+ struct drm_gem_object gem;
+ struct ttm_place placements[3];
+ int pin_count;
};
+static inline struct hibmc_bo *hibmc_bo(struct ttm_buffer_object *bo)
+{
+ return container_of(bo, struct hibmc_bo, bo);
+}
+
+static inline struct hibmc_bo *gem_to_hibmc_bo(struct drm_gem_object *gem)
+{
+ return container_of(gem, struct hibmc_bo, gem);
+}
+
void hibmc_set_power_mode(struct hibmc_drm_private *priv,
unsigned int power_mode);
void hibmc_set_current_gate(struct hibmc_drm_private *priv,
unsigned int gate);
+int hibmc_gem_create(struct drm_device *dev, u32 size, bool iskernel,
+ struct drm_gem_object **obj);
+int hibmc_mm_init(struct hibmc_drm_private *hibmc);
+void hibmc_mm_fini(struct hibmc_drm_private *hibmc);
+int hibmc_bo_pin(struct hibmc_bo *bo, u32 pl_flag, u64 *gpu_addr);
+int hibmc_bo_unpin(struct hibmc_bo *bo);
+void hibmc_gem_free_object(struct drm_gem_object *obj);
+int hibmc_dumb_create(struct drm_file *file, struct drm_device *dev,
+ struct drm_mode_create_dumb *args);
+int hibmc_dumb_mmap_offset(struct drm_file *file, struct drm_device *dev,
+ u32 handle, u64 *offset);
+int hibmc_mmap(struct file *filp, struct vm_area_struct *vma);
+
#endif
diff --git a/drivers/gpu/drm/hisilicon/hibmc/hibmc_ttm.c b/drivers/gpu/drm/hisilicon/hibmc/hibmc_ttm.c
new file mode 100644
index 000000000000..036d3ac06e54
--- /dev/null
+++ b/drivers/gpu/drm/hisilicon/hibmc/hibmc_ttm.c
@@ -0,0 +1,485 @@
+/* Hisilicon Hibmc SoC drm driver
+ *
+ * Based on the bochs drm driver.
+ *
+ * Copyright (c) 2016 Huawei Limited.
+ *
+ * Author:
+ * Rongrong Zou <zourongrong@huawei.com>
+ * Rongrong Zou <zourongrong@gmail.com>
+ * Jianhua Li <lijianhua@huawei.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ */
+
+#include <ttm/ttm_page_alloc.h>
+
+#include "hibmc_drm_drv.h"
+
+#define DRM_FILE_PAGE_OFFSET (0x100000000ULL >> PAGE_SHIFT)
+
+static inline struct hibmc_drm_private *
+hibmc_bdev(struct ttm_bo_device *bd)
+{
+ return container_of(bd, struct hibmc_drm_private, bdev);
+}
+
+static int
+hibmc_ttm_mem_global_init(struct drm_global_reference *ref)
+{
+ return ttm_mem_global_init(ref->object);
+}
+
+static void
+hibmc_ttm_mem_global_release(struct drm_global_reference *ref)
+{
+ ttm_mem_global_release(ref->object);
+}
+
+static int hibmc_ttm_global_init(struct hibmc_drm_private *hibmc)
+{
+ int ret;
+
+ hibmc->mem_global_ref.global_type = DRM_GLOBAL_TTM_MEM;
+ hibmc->mem_global_ref.size = sizeof(struct ttm_mem_global);
+ hibmc->mem_global_ref.init = &hibmc_ttm_mem_global_init;
+ hibmc->mem_global_ref.release = &hibmc_ttm_mem_global_release;
+ ret = drm_global_item_ref(&hibmc->mem_global_ref);
+ if (ret) {
+ DRM_ERROR("could not get ref on ttm global: %d\n", ret);
+ return ret;
+ }
+
+ hibmc->bo_global_ref.mem_glob =
+ hibmc->mem_global_ref.object;
+ hibmc->bo_global_ref.ref.global_type = DRM_GLOBAL_TTM_BO;
+ hibmc->bo_global_ref.ref.size = sizeof(struct ttm_bo_global);
+ hibmc->bo_global_ref.ref.init = &ttm_bo_global_init;
+ hibmc->bo_global_ref.ref.release = &ttm_bo_global_release;
+ ret = drm_global_item_ref(&hibmc->bo_global_ref.ref);
+ if (ret) {
+ DRM_ERROR("failed setting up TTM BO subsystem: %d\n", ret);
+ drm_global_item_unref(&hibmc->mem_global_ref);
+ return ret;
+ }
+ return 0;
+}
+
+static void
+hibmc_ttm_global_release(struct hibmc_drm_private *hibmc)
+{
+ drm_global_item_unref(&hibmc->bo_global_ref.ref);
+ drm_global_item_unref(&hibmc->mem_global_ref);
+ hibmc->mem_global_ref.release = NULL;
+}
+
+static void hibmc_bo_ttm_destroy(struct ttm_buffer_object *tbo)
+{
+ struct hibmc_bo *bo = container_of(tbo, struct hibmc_bo, bo);
+
+ drm_gem_object_release(&bo->gem);
+ kfree(bo);
+}
+
+static bool hibmc_ttm_bo_is_hibmc_bo(struct ttm_buffer_object *bo)
+{
+ return bo->destroy == &hibmc_bo_ttm_destroy;
+}
+
+static int
+hibmc_bo_init_mem_type(struct ttm_bo_device *bdev, u32 type,
+ struct ttm_mem_type_manager *man)
+{
+ switch (type) {
+ case TTM_PL_SYSTEM:
+ man->flags = TTM_MEMTYPE_FLAG_MAPPABLE;
+ man->available_caching = TTM_PL_MASK_CACHING;
+ man->default_caching = TTM_PL_FLAG_CACHED;
+ break;
+ case TTM_PL_VRAM:
+ man->func = &ttm_bo_manager_func;
+ man->flags = TTM_MEMTYPE_FLAG_FIXED |
+ TTM_MEMTYPE_FLAG_MAPPABLE;
+ man->available_caching = TTM_PL_FLAG_UNCACHED |
+ TTM_PL_FLAG_WC;
+ man->default_caching = TTM_PL_FLAG_WC;
+ break;
+ default:
+ DRM_ERROR("unsupported memory type %u\n", type);
+ return -EINVAL;
+ }
+ return 0;
+}
+
+void hibmc_ttm_placement(struct hibmc_bo *bo, int domain)
+{
+ u32 count = 0;
+ u32 i;
+
+ bo->placement.placement = bo->placements;
+ bo->placement.busy_placement = bo->placements;
+ if (domain & TTM_PL_FLAG_VRAM)
+ bo->placements[count++].flags = TTM_PL_FLAG_WC |
+ TTM_PL_FLAG_UNCACHED | TTM_PL_FLAG_VRAM;
+ if (domain & TTM_PL_FLAG_SYSTEM)
+ bo->placements[count++].flags = TTM_PL_MASK_CACHING |
+ TTM_PL_FLAG_SYSTEM;
+ if (!count)
+ bo->placements[count++].flags = TTM_PL_MASK_CACHING |
+ TTM_PL_FLAG_SYSTEM;
+
+ bo->placement.num_placement = count;
+ bo->placement.num_busy_placement = count;
+ for (i = 0; i < count; i++) {
+ bo->placements[i].fpfn = 0;
+ bo->placements[i].lpfn = 0;
+ }
+}
+
+static void
+hibmc_bo_evict_flags(struct ttm_buffer_object *bo, struct ttm_placement *pl)
+{
+ struct hibmc_bo *hibmcbo = hibmc_bo(bo);
+
+ if (!hibmc_ttm_bo_is_hibmc_bo(bo))
+ return;
+
+ hibmc_ttm_placement(hibmcbo, TTM_PL_FLAG_SYSTEM);
+ *pl = hibmcbo->placement;
+}
+
+static int hibmc_bo_verify_access(struct ttm_buffer_object *bo,
+ struct file *filp)
+{
+ struct hibmc_bo *hibmcbo = hibmc_bo(bo);
+
+ return drm_vma_node_verify_access(&hibmcbo->gem.vma_node,
+ filp->private_data);
+}
+
+static int hibmc_ttm_io_mem_reserve(struct ttm_bo_device *bdev,
+ struct ttm_mem_reg *mem)
+{
+ struct ttm_mem_type_manager *man = &bdev->man[mem->mem_type];
+ struct hibmc_drm_private *hibmc = hibmc_bdev(bdev);
+
+ mem->bus.addr = NULL;
+ mem->bus.offset = 0;
+ mem->bus.size = mem->num_pages << PAGE_SHIFT;
+ mem->bus.base = 0;
+ mem->bus.is_iomem = false;
+ if (!(man->flags & TTM_MEMTYPE_FLAG_MAPPABLE))
+ return -EINVAL;
+ switch (mem->mem_type) {
+ case TTM_PL_SYSTEM:
+ /* system memory */
+ return 0;
+ case TTM_PL_VRAM:
+ mem->bus.offset = mem->start << PAGE_SHIFT;
+ mem->bus.base = pci_resource_start(hibmc->dev->pdev, 0);
+ mem->bus.is_iomem = true;
+ break;
+ default:
+ return -EINVAL;
+ }
+ return 0;
+}
+
+static void hibmc_ttm_backend_destroy(struct ttm_tt *tt)
+{
+ ttm_tt_fini(tt);
+ kfree(tt);
+}
+
+static struct ttm_backend_func hibmc_tt_backend_func = {
+ .destroy = &hibmc_ttm_backend_destroy,
+};
+
+static struct ttm_tt *hibmc_ttm_tt_create(struct ttm_bo_device *bdev,
+ unsigned long size,
+ u32 page_flags,
+ struct page *dummy_read_page)
+{
+ struct ttm_tt *tt;
+ int ret;
+
+ tt = kzalloc(sizeof(*tt), GFP_KERNEL);
+ if (!tt) {
+ DRM_ERROR("failed to allocate ttm_tt\n");
+ return NULL;
+ }
+ tt->func = &hibmc_tt_backend_func;
+ ret = ttm_tt_init(tt, bdev, size, page_flags, dummy_read_page);
+ if (ret) {
+ DRM_ERROR("failed to initialize ttm_tt: %d\n", ret);
+ kfree(tt);
+ return NULL;
+ }
+ return tt;
+}
+
+static int hibmc_ttm_tt_populate(struct ttm_tt *ttm)
+{
+ return ttm_pool_populate(ttm);
+}
+
+static void hibmc_ttm_tt_unpopulate(struct ttm_tt *ttm)
+{
+ ttm_pool_unpopulate(ttm);
+}
+
+struct ttm_bo_driver hibmc_bo_driver = {
+ .ttm_tt_create = hibmc_ttm_tt_create,
+ .ttm_tt_populate = hibmc_ttm_tt_populate,
+ .ttm_tt_unpopulate = hibmc_ttm_tt_unpopulate,
+ .init_mem_type = hibmc_bo_init_mem_type,
+ .evict_flags = hibmc_bo_evict_flags,
+ .move = NULL,
+ .verify_access = hibmc_bo_verify_access,
+ .io_mem_reserve = &hibmc_ttm_io_mem_reserve,
+ .io_mem_free = NULL,
+ .lru_tail = &ttm_bo_default_lru_tail,
+ .swap_lru_tail = &ttm_bo_default_swap_lru_tail,
+};
+
+int hibmc_mm_init(struct hibmc_drm_private *hibmc)
+{
+ int ret;
+ struct drm_device *dev = hibmc->dev;
+ struct ttm_bo_device *bdev = &hibmc->bdev;
+
+ ret = hibmc_ttm_global_init(hibmc);
+ if (ret)
+ return ret;
+
+ ret = ttm_bo_device_init(&hibmc->bdev,
+ hibmc->bo_global_ref.ref.object,
+ &hibmc_bo_driver,
+ dev->anon_inode->i_mapping,
+ DRM_FILE_PAGE_OFFSET,
+ true);
+ if (ret) {
+ hibmc_ttm_global_release(hibmc);
+ DRM_ERROR("error initializing bo driver: %d\n", ret);
+ return ret;
+ }
+
+ ret = ttm_bo_init_mm(bdev, TTM_PL_VRAM,
+ hibmc->fb_size >> PAGE_SHIFT);
+ if (ret) {
+ hibmc_ttm_global_release(hibmc);
+ DRM_ERROR("failed ttm VRAM init: %d\n", ret);
+ return ret;
+ }
+
+ hibmc->mm_inited = true;
+ return 0;
+}
+
+void hibmc_mm_fini(struct hibmc_drm_private *hibmc)
+{
+ if (!hibmc->mm_inited)
+ return;
+
+ ttm_bo_device_release(&hibmc->bdev);
+ hibmc_ttm_global_release(hibmc);
+ hibmc->mm_inited = false;
+}
+
+static void hibmc_bo_unref(struct hibmc_bo **bo)
+{
+ struct ttm_buffer_object *tbo;
+
+ if ((*bo) == NULL)
+ return;
+
+ tbo = &((*bo)->bo);
+ ttm_bo_unref(&tbo);
+ *bo = NULL;
+}
+
+int hibmc_bo_create(struct drm_device *dev, int size, int align,
+ u32 flags, struct hibmc_bo **phibmcbo)
+{
+ struct hibmc_drm_private *hibmc = dev->dev_private;
+ struct hibmc_bo *hibmcbo;
+ size_t acc_size;
+ int ret;
+
+ hibmcbo = kzalloc(sizeof(*hibmcbo), GFP_KERNEL);
+ if (!hibmcbo) {
+ DRM_ERROR("failed to allocate hibmcbo\n");
+ return -ENOMEM;
+ }
+ ret = drm_gem_object_init(dev, &hibmcbo->gem, size);
+ if (ret) {
+ DRM_ERROR("failed to initialize drm gem object: %d\n", ret);
+ kfree(hibmcbo);
+ return ret;
+ }
+
+ hibmcbo->bo.bdev = &hibmc->bdev;
+
+ hibmc_ttm_placement(hibmcbo, TTM_PL_FLAG_VRAM | TTM_PL_FLAG_SYSTEM);
+
+ acc_size = ttm_bo_dma_acc_size(&hibmc->bdev, size,
+ sizeof(struct hibmc_bo));
+
+ ret = ttm_bo_init(&hibmc->bdev, &hibmcbo->bo, size,
+ ttm_bo_type_device, &hibmcbo->placement,
+ align >> PAGE_SHIFT, false, NULL, acc_size,
+ NULL, NULL, hibmc_bo_ttm_destroy);
+ if (ret) {
+ hibmc_bo_unref(&hibmcbo);
+ DRM_ERROR("failed to initialize ttm_bo: %d\n", ret);
+ return ret;
+ }
+
+ *phibmcbo = hibmcbo;
+ return 0;
+}
+
+int hibmc_bo_pin(struct hibmc_bo *bo, u32 pl_flag, u64 *gpu_addr)
+{
+ int i, ret;
+
+ if (bo->pin_count) {
+ bo->pin_count++;
+ if (gpu_addr)
+ *gpu_addr = bo->bo.offset;
+ return 0;
+ }
+
+ hibmc_ttm_placement(bo, pl_flag);
+ for (i = 0; i < bo->placement.num_placement; i++)
+ bo->placements[i].flags |= TTM_PL_FLAG_NO_EVICT;
+ ret = ttm_bo_validate(&bo->bo, &bo->placement, false, false);
+ if (ret)
+ return ret;
+
+ bo->pin_count = 1;
+ if (gpu_addr)
+ *gpu_addr = bo->bo.offset;
+ return 0;
+}
+
+int hibmc_bo_unpin(struct hibmc_bo *bo)
+{
+ int i, ret;
+
+ if (!bo->pin_count) {
+ DRM_ERROR("unpin bad %p\n", bo);
+ return 0;
+ }
+ bo->pin_count--;
+ if (bo->pin_count)
+ return 0;
+
+ for (i = 0; i < bo->placement.num_placement ; i++)
+ bo->placements[i].flags &= ~TTM_PL_FLAG_NO_EVICT;
+ ret = ttm_bo_validate(&bo->bo, &bo->placement, false, false);
+ if (ret) {
+ DRM_ERROR("validate failed for unpin: %d\n", ret);
+ return ret;
+ }
+
+ return 0;
+}
+
+int hibmc_mmap(struct file *filp, struct vm_area_struct *vma)
+{
+ struct drm_file *file_priv;
+ struct hibmc_drm_private *hibmc;
+
+ if (unlikely(vma->vm_pgoff < DRM_FILE_PAGE_OFFSET))
+ return -EINVAL;
+
+ file_priv = filp->private_data;
+ hibmc = file_priv->minor->dev->dev_private;
+ return ttm_bo_mmap(filp, vma, &hibmc->bdev);
+}
+
+int hibmc_gem_create(struct drm_device *dev, u32 size, bool iskernel,
+ struct drm_gem_object **obj)
+{
+ struct hibmc_bo *hibmcbo;
+ int ret;
+
+ *obj = NULL;
+
+ size = PAGE_ALIGN(size);
+ if (size == 0) {
+ DRM_ERROR("error: zero size\n");
+ return -EINVAL;
+ }
+
+ ret = hibmc_bo_create(dev, size, 0, 0, &hibmcbo);
+ if (ret) {
+ if (ret != -ERESTARTSYS)
+ DRM_ERROR("failed to allocate GEM object: %d\n", ret);
+ return ret;
+ }
+ *obj = &hibmcbo->gem;
+ return 0;
+}
+
+int hibmc_dumb_create(struct drm_file *file, struct drm_device *dev,
+ struct drm_mode_create_dumb *args)
+{
+ struct drm_gem_object *gobj;
+ u32 handle;
+ int ret;
+
+ args->pitch = ALIGN(args->width * DIV_ROUND_UP(args->bpp, 8), 16);
+ args->size = args->pitch * args->height;
+
+ ret = hibmc_gem_create(dev, args->size, false,
+ &gobj);
+ if (ret) {
+ DRM_ERROR("failed to create GEM object: %d\n", ret);
+ return ret;
+ }
+
+ ret = drm_gem_handle_create(file, gobj, &handle);
+ drm_gem_object_unreference_unlocked(gobj);
+ if (ret) {
+ DRM_ERROR("failed to unreference GEM object: %d\n", ret);
+ return ret;
+ }
+
+ args->handle = handle;
+ return 0;
+}
+
+void hibmc_gem_free_object(struct drm_gem_object *obj)
+{
+ struct hibmc_bo *hibmcbo = gem_to_hibmc_bo(obj);
+
+ hibmc_bo_unref(&hibmcbo);
+}
+
+static u64 hibmc_bo_mmap_offset(struct hibmc_bo *bo)
+{
+ return drm_vma_node_offset_addr(&bo->bo.vma_node);
+}
+
+int hibmc_dumb_mmap_offset(struct drm_file *file, struct drm_device *dev,
+ u32 handle, u64 *offset)
+{
+ struct drm_gem_object *obj;
+ struct hibmc_bo *bo;
+
+ obj = drm_gem_object_lookup(file, handle);
+ if (!obj)
+ return -ENOENT;
+
+ bo = gem_to_hibmc_bo(obj);
+ *offset = hibmc_bo_mmap_offset(bo);
+
+ drm_gem_object_unreference_unlocked(obj);
+ return 0;
+}