linux/drivers/char/drm/drm_scatter.c
Benjamin Herrenschmidt 6876b3baca drm: fix for non-coherent DMA PowerPC
This patch fixes bits of the DRM so to make the radeon DRI work on
non-cache coherent PCI DMA variants of the PowerPC processors.

It moves the few places that needs change to wrappers to that
other architectures with similar issues can easily add their
own changes to those wrappers, at least until we have more useful
generic kernel API.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: "Luck, Tony" <tony.luck@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Dave Airlie <airlied@linux.ie>
2008-03-30 07:57:57 +10:00

228 lines
5.8 KiB
C

/**
* \file drm_scatter.c
* IOCTLs to manage scatter/gather memory
*
* \author Gareth Hughes <gareth@valinux.com>
*/
/*
* Created: Mon Dec 18 23:20:54 2000 by gareth@valinux.com
*
* Copyright 2000 VA Linux Systems, Inc., Sunnyvale, California.
* All Rights Reserved.
*
* Permission is hereby granted, free of charge, to any person obtaining a
* copy of this software and associated documentation files (the "Software"),
* to deal in the Software without restriction, including without limitation
* the rights to use, copy, modify, merge, publish, distribute, sublicense,
* and/or sell copies of the Software, and to permit persons to whom the
* Software is furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice (including the next
* paragraph) shall be included in all copies or substantial portions of the
* Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
* PRECISION INSIGHT AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
* OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
* ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
* DEALINGS IN THE SOFTWARE.
*/
#include <linux/vmalloc.h>
#include "drmP.h"
#define DEBUG_SCATTER 0
static inline void *drm_vmalloc_dma(unsigned long size)
{
#if defined(__powerpc__) && defined(CONFIG_NOT_COHERENT_CACHE)
return __vmalloc(size, GFP_KERNEL, PAGE_KERNEL | _PAGE_NO_CACHE);
#else
return vmalloc_32(size);
#endif
}
void drm_sg_cleanup(struct drm_sg_mem * entry)
{
struct page *page;
int i;
for (i = 0; i < entry->pages; i++) {
page = entry->pagelist[i];
if (page)
ClearPageReserved(page);
}
vfree(entry->virtual);
drm_free(entry->busaddr,
entry->pages * sizeof(*entry->busaddr), DRM_MEM_PAGES);
drm_free(entry->pagelist,
entry->pages * sizeof(*entry->pagelist), DRM_MEM_PAGES);
drm_free(entry, sizeof(*entry), DRM_MEM_SGLISTS);
}
#ifdef _LP64
# define ScatterHandle(x) (unsigned int)((x >> 32) + (x & ((1L << 32) - 1)))
#else
# define ScatterHandle(x) (unsigned int)(x)
#endif
int drm_sg_alloc(struct drm_device *dev, struct drm_scatter_gather * request)
{
struct drm_sg_mem *entry;
unsigned long pages, i, j;
DRM_DEBUG("\n");
if (!drm_core_check_feature(dev, DRIVER_SG))
return -EINVAL;
if (dev->sg)
return -EINVAL;
entry = drm_alloc(sizeof(*entry), DRM_MEM_SGLISTS);
if (!entry)
return -ENOMEM;
memset(entry, 0, sizeof(*entry));
pages = (request->size + PAGE_SIZE - 1) / PAGE_SIZE;
DRM_DEBUG("size=%ld pages=%ld\n", request->size, pages);
entry->pages = pages;
entry->pagelist = drm_alloc(pages * sizeof(*entry->pagelist),
DRM_MEM_PAGES);
if (!entry->pagelist) {
drm_free(entry, sizeof(*entry), DRM_MEM_SGLISTS);
return -ENOMEM;
}
memset(entry->pagelist, 0, pages * sizeof(*entry->pagelist));
entry->busaddr = drm_alloc(pages * sizeof(*entry->busaddr),
DRM_MEM_PAGES);
if (!entry->busaddr) {
drm_free(entry->pagelist,
entry->pages * sizeof(*entry->pagelist),
DRM_MEM_PAGES);
drm_free(entry, sizeof(*entry), DRM_MEM_SGLISTS);
return -ENOMEM;
}
memset((void *)entry->busaddr, 0, pages * sizeof(*entry->busaddr));
entry->virtual = drm_vmalloc_dma(pages << PAGE_SHIFT);
if (!entry->virtual) {
drm_free(entry->busaddr,
entry->pages * sizeof(*entry->busaddr), DRM_MEM_PAGES);
drm_free(entry->pagelist,
entry->pages * sizeof(*entry->pagelist),
DRM_MEM_PAGES);
drm_free(entry, sizeof(*entry), DRM_MEM_SGLISTS);
return -ENOMEM;
}
/* This also forces the mapping of COW pages, so our page list
* will be valid. Please don't remove it...
*/
memset(entry->virtual, 0, pages << PAGE_SHIFT);
entry->handle = ScatterHandle((unsigned long)entry->virtual);
DRM_DEBUG("handle = %08lx\n", entry->handle);
DRM_DEBUG("virtual = %p\n", entry->virtual);
for (i = (unsigned long)entry->virtual, j = 0; j < pages;
i += PAGE_SIZE, j++) {
entry->pagelist[j] = vmalloc_to_page((void *)i);
if (!entry->pagelist[j])
goto failed;
SetPageReserved(entry->pagelist[j]);
}
request->handle = entry->handle;
dev->sg = entry;
#if DEBUG_SCATTER
/* Verify that each page points to its virtual address, and vice
* versa.
*/
{
int error = 0;
for (i = 0; i < pages; i++) {
unsigned long *tmp;
tmp = page_address(entry->pagelist[i]);
for (j = 0;
j < PAGE_SIZE / sizeof(unsigned long);
j++, tmp++) {
*tmp = 0xcafebabe;
}
tmp = (unsigned long *)((u8 *) entry->virtual +
(PAGE_SIZE * i));
for (j = 0;
j < PAGE_SIZE / sizeof(unsigned long);
j++, tmp++) {
if (*tmp != 0xcafebabe && error == 0) {
error = 1;
DRM_ERROR("Scatter allocation error, "
"pagelist does not match "
"virtual mapping\n");
}
}
tmp = page_address(entry->pagelist[i]);
for (j = 0;
j < PAGE_SIZE / sizeof(unsigned long);
j++, tmp++) {
*tmp = 0;
}
}
if (error == 0)
DRM_ERROR("Scatter allocation matches pagelist\n");
}
#endif
return 0;
failed:
drm_sg_cleanup(entry);
return -ENOMEM;
}
EXPORT_SYMBOL(drm_sg_alloc);
int drm_sg_alloc_ioctl(struct drm_device *dev, void *data,
struct drm_file *file_priv)
{
struct drm_scatter_gather *request = data;
return drm_sg_alloc(dev, request);
}
int drm_sg_free(struct drm_device *dev, void *data,
struct drm_file *file_priv)
{
struct drm_scatter_gather *request = data;
struct drm_sg_mem *entry;
if (!drm_core_check_feature(dev, DRIVER_SG))
return -EINVAL;
entry = dev->sg;
dev->sg = NULL;
if (!entry || entry->handle != request->handle)
return -EINVAL;
DRM_DEBUG("virtual = %p\n", entry->virtual);
drm_sg_cleanup(entry);
return 0;
}