Subject: [PATCH v6 2/9] drm/hisilicon/hibmc: Add video memory management

From: [email-masked] (Rongrong Zou)
Date: Fri, 11 Nov 2016 19:16:51 +0800

? 2016/11/11 1:35, Sean Paul ??:
> On Fri, Oct 28, 2016 at 3:27 AM, Rongrong Zou <[email-masked]> wrote:
>> 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 <[email-masked]>
>> ---
>>   drivers/gpu/drm/hisilicon/hibmc/Kconfig         |   1 +
>>   drivers/gpu/drm/hisilicon/hibmc/Makefile        |   2 +-
>>   drivers/gpu/drm/hisilicon/hibmc/hibmc_drm_drv.c |  12 +
>>   drivers/gpu/drm/hisilicon/hibmc/hibmc_drm_drv.h |  46 +++
>>   drivers/gpu/drm/hisilicon/hibmc/hibmc_ttm.c     | 490 ++++++++++++++++++++++++
>>   5 files changed, 550 insertions(+), 1 deletion(-)
>>   create mode 100644 drivers/gpu/drm/hisilicon/hibmc/hibmc_ttm.c
>>
>> diff --git a/drivers/gpu/drm/hisilicon/hibmc/Kconfig b/drivers/gpu/drm/hisilicon/hibmc/Kconfig
>> index a9af90d..bcb8c18 100644
>> --- a/drivers/gpu/drm/hisilicon/hibmc/Kconfig
>> +++ b/drivers/gpu/drm/hisilicon/hibmc/Kconfig
>> @@ -1,6 +1,7 @@
>>   config DRM_HISI_HIBMC
>>          tristate "DRM Support for Hisilicon Hibmc"
>>          depends on DRM && PCI
>> +       select DRM_TTM
>>
>>          help
>>            Choose this option if you have a Hisilicon Hibmc soc chipset.
>> diff --git a/drivers/gpu/drm/hisilicon/hibmc/Makefile b/drivers/gpu/drm/hisilicon/hibmc/Makefile
>> index 97cf4a0..d5c40b8 100644
>> --- a/drivers/gpu/drm/hisilicon/hibmc/Makefile
>> +++ b/drivers/gpu/drm/hisilicon/hibmc/Makefile
>> @@ -1,5 +1,5 @@
>>   ccflags-y := -Iinclude/drm
>> -hibmc-drm-y := hibmc_drm_drv.o hibmc_drm_power.o
>> +hibmc-drm-y := hibmc_drm_drv.o hibmc_drm_power.o hibmc_ttm.o
>>
>>   obj-$(CONFIG_DRM_HISI_HIBMC)   +=hibmc-drm.o
>>   #obj-y += 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 4669d42..81f4301 100644
>> --- a/drivers/gpu/drm/hisilicon/hibmc/hibmc_drm_drv.c
>> +++ b/drivers/gpu/drm/hisilicon/hibmc/hibmc_drm_drv.c
>> @@ -31,6 +31,7 @@
>>   #ifdef CONFIG_COMPAT
>>          .compat_ioctl   = drm_compat_ioctl,
>>   #endif
>> +       .mmap           = hibmc_mmap,
>>          .poll           = drm_poll,
>>          .read           = drm_read,
>>          .llseek         = no_llseek,
>> @@ -46,6 +47,8 @@ static void hibmc_disable_vblank(struct drm_device *dev, unsigned int pipe)
>>   }
>>
>>   static struct drm_driver hibmc_driver = {
>> +       .driver_features        = DRIVER_GEM,
>> +
>
> nit: extra space
>
>>          .fops                   = &hibmc_fops,
>>          .name                   = "hibmc",
>>          .date                   = "20160828",
>> @@ -55,6 +58,10 @@ static void hibmc_disable_vblank(struct drm_device *dev, unsigned int pipe)
>>          .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)
>> @@ -163,6 +170,7 @@ static int hibmc_unload(struct drm_device *dev)
>>   {
>>          struct hibmc_drm_device *hidev = dev->dev_private;
>>
>> +       hibmc_mm_fini(hidev);
>>          hibmc_hw_fini(hidev);
>>          dev->dev_private = NULL;
>>          return 0;
>> @@ -183,6 +191,10 @@ static int hibmc_load(struct drm_device *dev, unsigned long flags)
>>          if (ret)
>>                  goto err;
>>
>> +       ret = hibmc_mm_init(hidev);
>> +       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 0037341..db8d80e 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/ttm/ttm_bo_driver.h>
>> +#include <drm/drm_gem.h>
>
> nit: alphabetize

will fix it, thanks.

>
>>
>>   struct hibmc_drm_device {
>>          /* hw */
>> @@ -30,6 +32,50 @@ struct hibmc_drm_device {
>>
>>          /* drm */
>>          struct drm_device  *dev;
>> +
>> +       /* ttm */
>> +       struct {
>> +               struct drm_global_reference mem_global_ref;
>> +               struct ttm_bo_global_ref bo_global_ref;
>> +               struct ttm_bo_device bdev;
>> +               bool initialized;
>> +       } ttm;
>
> I don't think you gain anything other than keystrokes from the substruct

I'm sorry i didn't catch you, i looked at the all drivers used ttm such
as ast/bochs/cirrus/mgag200/qxl/virtio_gpu, they all embedded the ttm substruct
into the driver-private struct.

so do you mean
struct hibmc_drm_device {
	/* hw */
	void __iomem   *mmio;
	void __iomem   *fb_map;
	unsigned long  fb_base;
	unsigned long  fb_size;

	/* drm */
	struct drm_device  *dev;
	struct drm_plane plane;
	struct drm_crtc crtc;
	struct drm_encoder encoder;
	struct drm_connector connector;
	bool mode_config_initialized;

	/* 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);
>> +}
>> +
>> +#define DRM_FILE_PAGE_OFFSET (0x100000000ULL >> PAGE_SHIFT)
>
> Hide this in ttm.c

ok, will do that.
thanks for pointing it out.

>
>> +
>> +int hibmc_gem_create(struct drm_device *dev, u32 size, bool iskernel,
>> +                    struct drm_gem_object **obj);
>> +
>> +int hibmc_mm_init(struct hibmc_drm_device *hibmc);
>> +void hibmc_mm_fini(struct hibmc_drm_device *hibmc);
>> +int hibmc_bo_pin(struct hibmc_bo *bo, u32 pl_flag, u64 *gpu_addr);
>> +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 0000000..0802ebd
>> --- /dev/null
>> +++ b/drivers/gpu/drm/hisilicon/hibmc/hibmc_ttm.c
>> @@ -0,0 +1,490 @@
>> +/* Hisilicon Hibmc SoC drm driver
>> + *
>> + * Based on the bochs drm driver.
>> + *
>> + * Copyright (c) 2016 Huawei Limited.
>> + *
>> + * Author:
>> + *     Rongrong Zou <[email-masked]>
>> + *     Rongrong Zou <[email-masked]>
>> + *     Jianhua Li <[email-masked]>
>> + *
>> + * 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 "hibmc_drm_drv.h"
>> +#include <ttm/ttm_page_alloc.h>
>> +#include <drm/drm_crtc_helper.h>
>> +#include <drm/drm_atomic_helper.h>
>> +
>> +static inline struct hibmc_drm_device *
>> +hibmc_bdev(struct ttm_bo_device *bd)
>> +{
>> +       return container_of(bd, struct hibmc_drm_device, ttm.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_device *hibmc)
>> +{
>> +       struct drm_global_reference *global_ref;
>> +       int r;
>
> nit: try not to use one character variable names unless it's for the
> purpose of a loop (ie: i,j). You also use ret elsewhere in the driver,
> so it'd be nice to remain consistent

the whole file is delivered from bochs ttm, i didn't modify anything except
some checkpatch warnings and the 'hibmc_' prefix. Unfortunately, some
problems were delivered too.

>
>> +
>> +       global_ref = &hibmc->ttm.mem_global_ref;
>
> I think using the global_ref local obfuscates what you're doing here.
> It saves you 6 characters while typing, but adds a layer of
> indirection for all future readers.
>
>> +       global_ref->global_type = DRM_GLOBAL_TTM_MEM;
>> +       global_ref->size = sizeof(struct ttm_mem_global);
>> +       global_ref->init = &hibmc_ttm_mem_global_init;
>> +       global_ref->release = &hibmc_ttm_mem_global_release;
>> +       r = drm_global_item_ref(global_ref);
>> +       if (r != 0) {
>
> nit: if (r)

will fix it,
thanks.
BTW, i wonder why checkpatch.pl didn't report it.

>
>> +               DRM_ERROR("Failed setting up TTM memory accounting subsystem.\n"
>> +                        );
>
> Breaking up the line for one character is probably not worthwhile, and
> you should really print the error. How about:
>
> DRM_ERROR("Could not get ref on ttm global ret=%d.\n", ret);

i like your solution, thanks.

>
>
>> +               return r;
>> +       }
>> +
>> +       hibmc->ttm.bo_global_ref.mem_glob =
>> +               hibmc->ttm.mem_global_ref.object;
>> +       global_ref = &hibmc->ttm.bo_global_ref.ref;
>> +       global_ref->global_type = DRM_GLOBAL_TTM_BO;
>> +       global_ref->size = sizeof(struct ttm_bo_global);
>> +       global_ref->init = &ttm_bo_global_init;
>> +       global_ref->release = &ttm_bo_global_release;
>> +       r = drm_global_item_ref(global_ref);
>> +       if (r != 0) {
>> +               DRM_ERROR("Failed setting up TTM BO subsystem.\n");
>> +               drm_global_item_unref(&hibmc->ttm.mem_global_ref);
>> +               return r;
>> +       }
>> +       return 0;
>> +}
>> +
>> +static void
>> +hibmc_ttm_global_release(struct hibmc_drm_device *hibmc)
>> +{
>> +       if (!hibmc->ttm.mem_global_ref.release)
>
> Are you actually hitting this condition? This seems like it's papering
> over something else.

it was also delivered from others, i looked at the xxx_ttm_global_init
function, 'mem_global_ref.release' is assigned unconditionally, so i
think this condition never be hit, it may be hit when release twice,
but this won't take place in my driver.

>
>> +               return;
>> +
>> +       drm_global_item_unref(&hibmc->ttm.bo_global_ref.ref);
>> +       drm_global_item_unref(&hibmc->ttm.mem_global_ref);
>> +       hibmc->ttm.mem_global_ref.release = NULL;
>> +}
>> +
>> +static void hibmc_bo_ttm_destroy(struct ttm_buffer_object *tbo)
>> +{
>> +       struct hibmc_bo *bo;
>> +
>> +       bo = container_of(tbo, struct hibmc_bo, bo);
>
> nit: No need to split this into a separate line.

agreed, thanks.

>
>> +
>> +       drm_gem_object_release(&bo->gem);
>> +       kfree(bo);
>> +}
>> +
>> +static bool hibmc_ttm_bo_is_hibmc_bo(struct ttm_buffer_object *bo)
>> +{
>> +       if (bo->destroy == &hibmc_bo_ttm_destroy)
>> +               return true;
>> +       return false;
>
> return bo->destroy == &hibmc_bo_ttm_destroy;

looks better to me.

>
>> +}
>> +
>> +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 c = 0;
>
> Can you please use a more descriptive name than 'c'?

ok, will do that.

>
>> +       u32 i;
>> +
>> +       bo->placement.placement = bo->placements;
>> +       bo->placement.busy_placement = bo->placements;
>> +       if (domain & TTM_PL_FLAG_VRAM)
>> +               bo->placements[c++].flags = TTM_PL_FLAG_WC |
>> +               TTM_PL_FLAG_UNCACHED | TTM_PL_FLAG_VRAM;
>
> nit: you're alignment is off here and below

is it correct?

	if (domain & TTM_PL_FLAG_VRAM)
		bo->placements[c++].flags = TTM_PL_FLAG_WC |
			TTM_PL_FLAG_UNCACHED | TTM_PL_FLAG_VRAM;
	if (domain & TTM_PL_FLAG_SYSTEM)
		bo->placements[c++].flags = TTM_PL_MASK_CACHING |
			TTM_PL_FLAG_SYSTEM;
	if (!c)
		bo->placements[c++].flags = TTM_PL_MASK_CACHING |
			TTM_PL_FLAG_SYSTEM;

>
>> +       if (domain & TTM_PL_FLAG_SYSTEM)
>> +               bo->placements[c++].flags = TTM_PL_MASK_CACHING |
>> +               TTM_PL_FLAG_SYSTEM;
>> +       if (!c)
>> +               bo->placements[c++].flags = TTM_PL_MASK_CACHING |
>> +               TTM_PL_FLAG_SYSTEM;
>> +
>> +       bo->placement.num_placement = c;
>> +       bo->placement.num_busy_placement = c;
>> +       for (i = 0; i < c; ++i) {
>
> nit: we tend towards post-increment in kernel

agreed, thanks.

>
>> +               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_device *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_io_mem_free(struct ttm_bo_device *bdev,
>> +                                 struct ttm_mem_reg *mem)
>> +{
>> +}
>
> No need to stub this, the caller does a NULL-check before invoking

will delete it, thanks.

>
>> +
>> +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;
>> +
>> +       tt = kzalloc(sizeof(*tt), GFP_KERNEL);
>> +       if (!tt)
>
> Print error

ok, will do that, thanks.

>
>> +               return NULL;
>> +       tt->func = &hibmc_tt_backend_func;
>> +       if (ttm_tt_init(tt, bdev, size, page_flags, dummy_read_page)) {
>
> Here too?

ditto

>
>> +               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            = &hibmc_ttm_io_mem_free,
>> +       .lru_tail               = &ttm_bo_default_lru_tail,
>> +       .swap_lru_tail          = &ttm_bo_default_swap_lru_tail,
>> +};
>> +
>> +int hibmc_mm_init(struct hibmc_drm_device *hibmc)
>> +{
>> +       int ret;
>> +       struct drm_device *dev = hibmc->dev;
>> +       struct ttm_bo_device *bdev = &hibmc->ttm.bdev;
>> +
>> +       ret = hibmc_ttm_global_init(hibmc);
>> +       if (ret)
>> +               return ret;
>> +
>> +       ret = ttm_bo_device_init(&hibmc->ttm.bdev,
>> +                                hibmc->ttm.bo_global_ref.ref.object,
>> +                                &hibmc_bo_driver,
>> +                                dev->anon_inode->i_mapping,
>> +                                DRM_FILE_PAGE_OFFSET,
>> +                                true);
>> +       if (ret) {
>
> Call hibmc_ttm_global_release here?

agreed, thanks for pointing it out.

>
>> +               DRM_ERROR("Error initialising bo driver; %d\n", ret);
>> +               return ret;
>> +       }
>> +
>> +       ret = ttm_bo_init_mm(bdev, TTM_PL_VRAM,
>> +                            hibmc->fb_size >> PAGE_SHIFT);
>> +       if (ret) {
>
> Clean up here as well?

ditto

>
>> +               DRM_ERROR("Failed ttm VRAM init: %d\n", ret);
>> +               return ret;
>> +       }
>> +
>> +       hibmc->mm_inited = true;
>> +       return 0;
>> +}
>> +
>> +void hibmc_mm_fini(struct hibmc_drm_device *hibmc)
>> +{
>> +       if (!hibmc->mm_inited)
>> +               return;
>> +
>> +       ttm_bo_device_release(&hibmc->ttm.bdev);
>> +       hibmc_ttm_global_release(hibmc);
>> +       hibmc->mm_inited = false;
>> +}
>> +
>> +int hibmc_bo_create(struct drm_device *dev, int size, int align,
>> +                   u32 flags, struct hibmc_bo **phibmcbo)
>> +{
>> +       struct hibmc_drm_device *hibmc = dev->dev_private;
>> +       struct hibmc_bo *hibmcbo;
>> +       size_t acc_size;
>> +       int ret;
>> +
>> +       hibmcbo = kzalloc(sizeof(*hibmcbo), GFP_KERNEL);
>> +       if (!hibmcbo)
>> +               return -ENOMEM;
>> +
>> +       ret = drm_gem_object_init(dev, &hibmcbo->gem, size);
>> +       if (ret) {
>> +               kfree(hibmcbo);
>> +               return ret;
>> +       }
>> +
>> +       hibmcbo->bo.bdev = &hibmc->ttm.bdev;
>> +
>> +       hibmc_ttm_placement(hibmcbo, TTM_PL_FLAG_VRAM | TTM_PL_FLAG_SYSTEM);
>> +
>> +       acc_size = ttm_bo_dma_acc_size(&hibmc->ttm.bdev, size,
>> +                                      sizeof(struct hibmc_bo));
>> +
>> +       ret = ttm_bo_init(&hibmc->ttm.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)
>
> Missing hibmcbo clean up here

i looked at all other ttm drivers and all of them return directly when ttm_bo_init
failed, however, i think it is better to clean up here, should i call
hibmc_bo_unref(&hibmc_bo) here ?

>
>> +               return ret;
>> +
>> +       *phibmcbo = hibmcbo;
>> +       return 0;
>> +}
>> +
>> +static inline u64 hibmc_bo_gpu_offset(struct hibmc_bo *bo)
>> +{
>> +       return bo->bo.offset;
>> +}
>
> I don't think this function provides any value

do you nean i use bo->bo.offset instead of calling hibmc_bo_gpu_offset()?

>
>> +
>> +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 = hibmc_bo_gpu_offset(bo);
>
> Are you missing a return here?

Thanks for pointing it out!

>
>> +       }
>> +
>> +       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 = hibmc_bo_gpu_offset(bo);
>> +       return 0;
>> +}
>> +
>> +int hibmc_bo_push_sysram(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;
>> +
>> +       if (bo->kmap.virtual)
>
> ttm_bo_kunmap already does this check so you don't have to

agreed. will remove this condition.

>
>> +               ttm_bo_kunmap(&bo->kmap);
>> +
>> +       hibmc_ttm_placement(bo, TTM_PL_FLAG_SYSTEM);
>> +       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("pushing to VRAM failed\n");
>
> Print ret

ok, thanks.

>
>> +               return ret;
>> +       }
>> +       return 0;
>> +}
>> +
>> +int hibmc_mmap(struct file *filp, struct vm_area_struct *vma)
>> +{
>> +       struct drm_file *file_priv;
>> +       struct hibmc_drm_device *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->ttm.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)
>
> Print error

ditto

>
>> +               return -EINVAL;
>> +
>> +       ret = hibmc_bo_create(dev, size, 0, 0, &hibmcbo);
>> +       if (ret) {
>> +               if (ret != -ERESTARTSYS)
>> +                       DRM_ERROR("failed to allocate GEM object\n");
>
> Print ret

ditto

>
>> +               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 * ((args->bpp + 7) / 8), 16);
>
> What's up with the bpp + 7 here? Perhaps you're looking for DIV_ROUND_UP?

Yes, that sounds sane.

>
>
>> +       args->size = args->pitch * args->height;
>> +
>> +       ret = hibmc_gem_create(dev, args->size, false,
>> +                              &gobj);
>> +       if (ret)
>> +               return ret;
>> +
>> +       ret = drm_gem_handle_create(file, gobj, &handle);
>> +       drm_gem_object_unreference_unlocked(gobj);
>> +       if (ret)
>
> Print error here

agreed.

>
>> +               return ret;
>> +
>> +       args->handle = handle;
>> +       return 0;
>> +}
>> +
>> +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;
>> +}
>> +
>> +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;
>> +}

Regards,
Rongrong.

>> --
>> 1.9.1
>>
>>
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