linux/drivers/gpu/drm/drm_cache.c
Daniel Vetter 6d5cd9cb1e drm: add helper to clflush a virtual address range
Useful when the page is already mapped to copy date in/out.

For -stable because the next patch (fixing phys obj pwrite) needs this
little helper function.

Tested-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: dri-devel@lists.freedesktop.org
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2012-03-27 13:19:45 +02:00

123 lines
3.3 KiB
C

/**************************************************************************
*
* Copyright (c) 2006-2007 Tungsten Graphics, Inc., Cedar Park, TX., USA
* 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, sub license, 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 NON-INFRINGEMENT. IN NO EVENT SHALL
* THE COPYRIGHT HOLDERS, AUTHORS 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.
*
**************************************************************************/
/*
* Authors: Thomas Hellström <thomas-at-tungstengraphics-dot-com>
*/
#include <linux/export.h>
#include "drmP.h"
#if defined(CONFIG_X86)
static void
drm_clflush_page(struct page *page)
{
uint8_t *page_virtual;
unsigned int i;
if (unlikely(page == NULL))
return;
page_virtual = kmap_atomic(page, KM_USER0);
for (i = 0; i < PAGE_SIZE; i += boot_cpu_data.x86_clflush_size)
clflush(page_virtual + i);
kunmap_atomic(page_virtual, KM_USER0);
}
static void drm_cache_flush_clflush(struct page *pages[],
unsigned long num_pages)
{
unsigned long i;
mb();
for (i = 0; i < num_pages; i++)
drm_clflush_page(*pages++);
mb();
}
static void
drm_clflush_ipi_handler(void *null)
{
wbinvd();
}
#endif
void
drm_clflush_pages(struct page *pages[], unsigned long num_pages)
{
#if defined(CONFIG_X86)
if (cpu_has_clflush) {
drm_cache_flush_clflush(pages, num_pages);
return;
}
if (on_each_cpu(drm_clflush_ipi_handler, NULL, 1) != 0)
printk(KERN_ERR "Timed out waiting for cache flush.\n");
#elif defined(__powerpc__)
unsigned long i;
for (i = 0; i < num_pages; i++) {
struct page *page = pages[i];
void *page_virtual;
if (unlikely(page == NULL))
continue;
page_virtual = kmap_atomic(page, KM_USER0);
flush_dcache_range((unsigned long)page_virtual,
(unsigned long)page_virtual + PAGE_SIZE);
kunmap_atomic(page_virtual, KM_USER0);
}
#else
printk(KERN_ERR "Architecture has no drm_cache.c support\n");
WARN_ON_ONCE(1);
#endif
}
EXPORT_SYMBOL(drm_clflush_pages);
void
drm_clflush_virt_range(char *addr, unsigned long length)
{
#if defined(CONFIG_X86)
if (cpu_has_clflush) {
char *end = addr + length;
mb();
for (; addr < end; addr += boot_cpu_data.x86_clflush_size)
clflush(addr);
clflush(end - 1);
mb();
return;
}
if (on_each_cpu(drm_clflush_ipi_handler, NULL, 1) != 0)
printk(KERN_ERR "Timed out waiting for cache flush.\n");
#else
printk(KERN_ERR "Architecture has no drm_cache.c support\n");
WARN_ON_ONCE(1);
#endif
}
EXPORT_SYMBOL(drm_clflush_virt_range);