/*
* 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 "gma_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 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_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.
*/
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 & GMA_GEM_CREATE_STOLEN) {
ret = psb_gem_create_stolen(file, dev, args->size,
&args->handle);
if (ret == 0)
return 0;
/* Fall throguh */
args->flags &= ~GMA_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);
}
