| // SPDX-License-Identifier: GPL-2.0-only |
| /* |
| * psb GEM interface |
| * |
| * Copyright (c) 2011, Intel Corporation. |
| * |
| * Authors: Alan Cox |
| * |
| * TODO: |
| * - we need to work out if the MMU is relevant (eg for |
| * accelerated operations on a GEM object) |
| */ |
| |
| #include <linux/pagemap.h> |
| |
| #include <drm/drm.h> |
| #include <drm/drm_vma_manager.h> |
| |
| #include "psb_drv.h" |
| |
| void psb_gem_free_object(struct drm_gem_object *obj) |
| { |
| struct gtt_range *gtt = container_of(obj, struct gtt_range, gem); |
| |
| /* Remove the list map if one is present */ |
| drm_gem_free_mmap_offset(obj); |
| drm_gem_object_release(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_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 |
| */ |
| int psb_gem_create(struct drm_file *file, struct drm_device *dev, u64 size, |
| u32 *handlep, int stolen, u32 align) |
| { |
| 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, PAGE_SIZE); |
| 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 so use -ENOMEM */ |
| dev_err(dev->dev, "GEM init failed for %lld\n", size); |
| return -ENOMEM; |
| } |
| /* Limit the object to 32bit mappings */ |
| mapping_set_gfp_mask(r->gem.filp->f_mapping, GFP_KERNEL | __GFP_DMA32); |
| /* 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_put_unlocked(&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, 0, |
| PAGE_SIZE); |
| } |
| |
| /** |
| * 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. |
| */ |
| vm_fault_t psb_gem_fault(struct vm_fault *vmf) |
| { |
| struct vm_area_struct *vma = vmf->vma; |
| struct drm_gem_object *obj; |
| struct gtt_range *r; |
| int err; |
| vm_fault_t 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_priv->mmap_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) { |
| err = psb_gtt_pin(r); |
| if (err < 0) { |
| dev_err(dev->dev, "gma500: pin failed: %d\n", err); |
| ret = vmf_error(err); |
| 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 = (vmf->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 = vmf_insert_pfn(vma, vmf->address, pfn); |
| fail: |
| mutex_unlock(&dev_priv->mmap_mutex); |
| |
| return ret; |
| } |