From: Alan Cox alan@linux.intel.com
The driver uses GEM along with a couple of small bits of wrapping of its own. The only real oddity here is the support for using the 'stolen' memory rather than wasting several MB.
We use a simple resource manager as we don't need to manage our space intensively at all as we only do 2D work. We also have a GTT which is entirely GPU facing so in the Cedarview case are not even allocating from host address space.
Signed-off-by: Alan Cox alan@linux.intel.com ---
drivers/gpu/drm/gma500/gem.c | 295 +++++++++++++++++++++++++++++++++++++ drivers/gpu/drm/gma500/gem_glue.c | 89 +++++++++++ drivers/gpu/drm/gma500/gem_glue.h | 2 3 files changed, 386 insertions(+), 0 deletions(-) create mode 100644 drivers/gpu/drm/gma500/gem.c create mode 100644 drivers/gpu/drm/gma500/gem_glue.c create mode 100644 drivers/gpu/drm/gma500/gem_glue.h
diff --git a/drivers/gpu/drm/gma500/gem.c b/drivers/gpu/drm/gma500/gem.c new file mode 100644 index 0000000..65fdd6b --- /dev/null +++ b/drivers/gpu/drm/gma500/gem.c @@ -0,0 +1,295 @@ +/* + * psb GEM interface + * + * Copyright (c) 2011, Intel Corporation. + * + * This program is free software; you can redistribute it and/or modify it + * under the terms and conditions of the GNU General Public License, + * version 2, as published by the Free Software Foundation. + * + * This program is distributed in the hope it will be useful, but WITHOUT + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for + * more details. + * + * You should have received a copy of the GNU General Public License along with + * this program; if not, write to the Free Software Foundation, Inc., + * 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA. + * + * Authors: Alan Cox + * + * TODO: + * - we need to work out if the MMU is relevant (eg for + * accelerated operations on a GEM object) + */ + +#include <drm/drmP.h> +#include <drm/drm.h> +#include "psb_drm.h" +#include "psb_drv.h" + +int psb_gem_init_object(struct drm_gem_object *obj) +{ + return -EINVAL; +} + +void psb_gem_free_object(struct drm_gem_object *obj) +{ + struct gtt_range *gtt = container_of(obj, struct gtt_range, gem); + drm_gem_object_release_wrap(obj); + /* This must occur last as it frees up the memory of the GEM object */ + psb_gtt_free_range(obj->dev, gtt); +} + +int psb_gem_get_aperture(struct drm_device *dev, void *data, + struct drm_file *file) +{ + return -EINVAL; +} + +/** + * psb_gem_dumb_map_gtt - buffer mapping for dumb interface + * @file: our drm client file + * @dev: drm device + * @handle: GEM handle to the object (from dumb_create) + * + * Do the necessary setup to allow the mapping of the frame buffer + * into user memory. We don't have to do much here at the moment. + */ +int psb_gem_dumb_map_gtt(struct drm_file *file, struct drm_device *dev, + uint32_t handle, uint64_t *offset) +{ + int ret = 0; + struct drm_gem_object *obj; + + if (!(dev->driver->driver_features & DRIVER_GEM)) + return -ENODEV; + + mutex_lock(&dev->struct_mutex); + + /* GEM does all our handle to object mapping */ + obj = drm_gem_object_lookup(dev, file, handle); + if (obj == NULL) { + ret = -ENOENT; + goto unlock; + } + /* What validation is needed here ? */ + + /* Make it mmapable */ + if (!obj->map_list.map) { + ret = gem_create_mmap_offset(obj); + if (ret) + goto out; + } + /* GEM should really work out the hash offsets for us */ + *offset = (u64)obj->map_list.hash.key << PAGE_SHIFT; +out: + drm_gem_object_unreference(obj); +unlock: + mutex_unlock(&dev->struct_mutex); + return ret; +} + +/** + * psb_gem_create - create a mappable object + * @file: the DRM file of the client + * @dev: our device + * @size: the size requested + * @handlep: returned handle (opaque number) + * + * Create a GEM object, fill in the boilerplate and attach a handle to + * it so that userspace can speak about it. This does the core work + * for the various methods that do/will create GEM objects for things + */ +static int psb_gem_create(struct drm_file *file, + struct drm_device *dev, uint64_t size, uint32_t *handlep) +{ + struct gtt_range *r; + int ret; + u32 handle; + + size = roundup(size, PAGE_SIZE); + + /* Allocate our object - for now a direct gtt range which is not + stolen memory backed */ + r = psb_gtt_alloc_range(dev, size, "gem", 0); + if (r == NULL) { + dev_err(dev->dev, "no memory for %lld byte GEM object\n", size); + return -ENOSPC; + } + /* Initialize the extra goodies GEM needs to do all the hard work */ + if (drm_gem_object_init(dev, &r->gem, size) != 0) { + psb_gtt_free_range(dev, r); + /* GEM doesn't give an error code and we don't have an + EGEMSUCKS so make something up for now - FIXME */ + dev_err(dev->dev, "GEM init failed for %lld\n", size); + return -ENOMEM; + } + /* Give the object a handle so we can carry it more easily */ + ret = drm_gem_handle_create(file, &r->gem, &handle); + if (ret) { + dev_err(dev->dev, "GEM handle failed for %p, %lld\n", + &r->gem, size); + drm_gem_object_release(&r->gem); + psb_gtt_free_range(dev, r); + return ret; + } + /* We have the initial and handle reference but need only one now */ + drm_gem_object_unreference(&r->gem); + *handlep = handle; + return 0; +} + +/** + * psb_gem_dumb_create - create a dumb buffer + * @drm_file: our client file + * @dev: our device + * @args: the requested arguments copied from userspace + * + * Allocate a buffer suitable for use for a frame buffer of the + * form described by user space. Give userspace a handle by which + * to reference it. + */ +int psb_gem_dumb_create(struct drm_file *file, struct drm_device *dev, + struct drm_mode_create_dumb *args) +{ + args->pitch = ALIGN(args->width * ((args->bpp + 7) / 8), 64); + args->size = args->pitch * args->height; + return psb_gem_create(file, dev, args->size, &args->handle); +} + +/** + * psb_gem_dumb_destroy - destroy a dumb buffer + * @file: client file + * @dev: our DRM device + * @handle: the object handle + * + * Destroy a handle that was created via psb_gem_dumb_create, at least + * we hope it was created that way. i915 seems to assume the caller + * does the checking but that might be worth review ! FIXME + */ +int psb_gem_dumb_destroy(struct drm_file *file, struct drm_device *dev, + uint32_t handle) +{ + /* No special work needed, drop the reference and see what falls out */ + return drm_gem_handle_delete(file, handle); +} + +/** + * psb_gem_fault - pagefault handler for GEM objects + * @vma: the VMA of the GEM object + * @vmf: fault detail + * + * Invoked when a fault occurs on an mmap of a GEM managed area. GEM + * does most of the work for us including the actual map/unmap calls + * but we need to do the actual page work. + * + * This code eventually needs to handle faulting objects in and out + * of the GTT and repacking it when we run out of space. We can put + * that off for now and for our simple uses + * + * The VMA was set up by GEM. In doing so it also ensured that the + * vma->vm_private_data points to the GEM object that is backing this + * mapping. + * + * FIXME + */ +int psb_gem_fault(struct vm_area_struct *vma, struct vm_fault *vmf) +{ + struct drm_gem_object *obj; + struct gtt_range *r; + int ret; + unsigned long pfn; + pgoff_t page_offset; + struct drm_device *dev; + struct drm_psb_private *dev_priv; + + obj = vma->vm_private_data; /* GEM object */ + dev = obj->dev; + dev_priv = dev->dev_private; + + r = container_of(obj, struct gtt_range, gem); /* Get the gtt range */ + + /* Make sure we don't parallel update on a fault, nor move or remove + something from beneath our feet */ + mutex_lock(&dev->struct_mutex); + + /* For now the mmap pins the object and it stays pinned. As things + stand that will do us no harm */ + if (r->mmapping == 0) { + ret = psb_gtt_pin(r); + if (ret < 0) { + dev_err(dev->dev, "gma500: pin failed: %d\n", ret); + goto fail; + } + r->mmapping = 1; + } + + /* Page relative to the VMA start - we must calculate this ourselves + because vmf->pgoff is the fake GEM offset */ + page_offset = ((unsigned long) vmf->virtual_address - vma->vm_start) + >> PAGE_SHIFT; + + /* CPU view of the page, don't go via the GART for CPU writes */ + if (r->stolen) + pfn = (dev_priv->stolen_base + r->offset) >> PAGE_SHIFT; + else + pfn = page_to_pfn(r->pages[page_offset]); + ret = vm_insert_pfn(vma, (unsigned long)vmf->virtual_address, pfn); + +fail: + mutex_unlock(&dev->struct_mutex); + switch (ret) { + case 0: + case -ERESTARTSYS: + case -EINTR: + return VM_FAULT_NOPAGE; + case -ENOMEM: + return VM_FAULT_OOM; + default: + return VM_FAULT_SIGBUS; + } +} + +static int psb_gem_create_stolen(struct drm_file *file, struct drm_device *dev, + int size, u32 *handle) +{ + struct gtt_range *gtt = psb_gtt_alloc_range(dev, size, "gem", 1); + if (gtt == NULL) + return -ENOMEM; + if (drm_gem_private_object_init(dev, >t->gem, size) != 0) + goto free_gtt; + if (drm_gem_handle_create(file, >t->gem, handle) == 0) + return 0; +free_gtt: + psb_gtt_free_range(dev, gtt); + return -ENOMEM; +} + +/* + * GEM interfaces for our specific client + */ +int psb_gem_create_ioctl(struct drm_device *dev, void *data, + struct drm_file *file) +{ + struct drm_psb_gem_create *args = data; + int ret; + if (args->flags & PSB_GEM_CREATE_STOLEN) { + ret = psb_gem_create_stolen(file, dev, args->size, + &args->handle); + if (ret == 0) + return 0; + /* Fall throguh */ + args->flags &= ~PSB_GEM_CREATE_STOLEN; + } + return psb_gem_create(file, dev, args->size, &args->handle); +} + +int psb_gem_mmap_ioctl(struct drm_device *dev, void *data, + struct drm_file *file) +{ + struct drm_psb_gem_mmap *args = data; + return dev->driver->dumb_map_offset(file, dev, + args->handle, &args->offset); +} + diff --git a/drivers/gpu/drm/gma500/gem_glue.c b/drivers/gpu/drm/gma500/gem_glue.c new file mode 100644 index 0000000..daac121 --- /dev/null +++ b/drivers/gpu/drm/gma500/gem_glue.c @@ -0,0 +1,89 @@ +/************************************************************************** + * Copyright (c) 2011, Intel Corporation. + * All Rights Reserved. + * + * This program is free software; you can redistribute it and/or modify it + * under the terms and conditions of the GNU General Public License, + * version 2, as published by the Free Software Foundation. + * + * This program is distributed in the hope it will be useful, but WITHOUT + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for + * more details. + * + * You should have received a copy of the GNU General Public License along with + * this program; if not, write to the Free Software Foundation, Inc., + * 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA. + * + **************************************************************************/ + +#include <drm/drmP.h> +#include <drm/drm.h> + +void drm_gem_object_release_wrap(struct drm_gem_object *obj) +{ + /* Remove the list map if one is present */ + if (obj->map_list.map) { + struct drm_gem_mm *mm = obj->dev->mm_private; + struct drm_map_list *list = &obj->map_list; + drm_ht_remove_item(&mm->offset_hash, &list->hash); + drm_mm_put_block(list->file_offset_node); + kfree(list->map); + list->map = NULL; + } + drm_gem_object_release(obj); +} + +/** + * gem_create_mmap_offset - invent an mmap offset + * @obj: our object + * + * Standard implementation of offset generation for mmap as is + * duplicated in several drivers. This belongs in GEM. + */ +int gem_create_mmap_offset(struct drm_gem_object *obj) +{ + struct drm_device *dev = obj->dev; + struct drm_gem_mm *mm = dev->mm_private; + struct drm_map_list *list; + struct drm_local_map *map; + int ret; + + list = &obj->map_list; + list->map = kzalloc(sizeof(struct drm_map_list), GFP_KERNEL); + if (list->map == NULL) + return -ENOMEM; + map = list->map; + map->type = _DRM_GEM; + map->size = obj->size; + map->handle = obj; + + list->file_offset_node = drm_mm_search_free(&mm->offset_manager, + obj->size / PAGE_SIZE, 0, 0); + if (!list->file_offset_node) { + dev_err(dev->dev, "failed to allocate offset for bo %d\n", + obj->name); + ret = -ENOSPC; + goto free_it; + } + list->file_offset_node = drm_mm_get_block(list->file_offset_node, + obj->size / PAGE_SIZE, 0); + if (!list->file_offset_node) { + ret = -ENOMEM; + goto free_it; + } + list->hash.key = list->file_offset_node->start; + ret = drm_ht_insert_item(&mm->offset_hash, &list->hash); + if (ret) { + dev_err(dev->dev, "failed to add to map hash\n"); + goto free_mm; + } + return 0; + +free_mm: + drm_mm_put_block(list->file_offset_node); +free_it: + kfree(list->map); + list->map = NULL; + return ret; +} diff --git a/drivers/gpu/drm/gma500/gem_glue.h b/drivers/gpu/drm/gma500/gem_glue.h new file mode 100644 index 0000000..ce5ce30 --- /dev/null +++ b/drivers/gpu/drm/gma500/gem_glue.h @@ -0,0 +1,2 @@ +extern void drm_gem_object_release_wrap(struct drm_gem_object *obj); +extern int gem_create_mmap_offset(struct drm_gem_object *obj);