linux-sg2042/drivers/gpu/drm/vmwgfx/vmwgfx_gmr.c

214 lines
5.4 KiB
C

/**************************************************************************
*
* Copyright © 2009 VMware, Inc., Palo Alto, CA., 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.
*
**************************************************************************/
#include "vmwgfx_drv.h"
#include "drmP.h"
#include "ttm/ttm_bo_driver.h"
/**
* FIXME: Adjust to the ttm lowmem / highmem storage to minimize
* the number of used descriptors.
*/
static int vmw_gmr_build_descriptors(struct list_head *desc_pages,
struct page *pages[],
unsigned long num_pages)
{
struct page *page, *next;
struct svga_guest_mem_descriptor *page_virtual = NULL;
struct svga_guest_mem_descriptor *desc_virtual = NULL;
unsigned int desc_per_page;
unsigned long prev_pfn;
unsigned long pfn;
int ret;
desc_per_page = PAGE_SIZE /
sizeof(struct svga_guest_mem_descriptor) - 1;
while (likely(num_pages != 0)) {
page = alloc_page(__GFP_HIGHMEM);
if (unlikely(page == NULL)) {
ret = -ENOMEM;
goto out_err;
}
list_add_tail(&page->lru, desc_pages);
/*
* Point previous page terminating descriptor to this
* page before unmapping it.
*/
if (likely(page_virtual != NULL)) {
desc_virtual->ppn = page_to_pfn(page);
kunmap_atomic(page_virtual, KM_USER0);
}
page_virtual = kmap_atomic(page, KM_USER0);
desc_virtual = page_virtual - 1;
prev_pfn = ~(0UL);
while (likely(num_pages != 0)) {
pfn = page_to_pfn(*pages);
if (pfn != prev_pfn + 1) {
if (desc_virtual - page_virtual ==
desc_per_page - 1)
break;
(++desc_virtual)->ppn = cpu_to_le32(pfn);
desc_virtual->num_pages = cpu_to_le32(1);
} else {
uint32_t tmp =
le32_to_cpu(desc_virtual->num_pages);
desc_virtual->num_pages = cpu_to_le32(tmp + 1);
}
prev_pfn = pfn;
--num_pages;
++pages;
}
(++desc_virtual)->ppn = cpu_to_le32(0);
desc_virtual->num_pages = cpu_to_le32(0);
}
if (likely(page_virtual != NULL))
kunmap_atomic(page_virtual, KM_USER0);
return 0;
out_err:
list_for_each_entry_safe(page, next, desc_pages, lru) {
list_del_init(&page->lru);
__free_page(page);
}
return ret;
}
static inline void vmw_gmr_free_descriptors(struct list_head *desc_pages)
{
struct page *page, *next;
list_for_each_entry_safe(page, next, desc_pages, lru) {
list_del_init(&page->lru);
__free_page(page);
}
}
static void vmw_gmr_fire_descriptors(struct vmw_private *dev_priv,
int gmr_id, struct list_head *desc_pages)
{
struct page *page;
if (unlikely(list_empty(desc_pages)))
return;
page = list_entry(desc_pages->next, struct page, lru);
mutex_lock(&dev_priv->hw_mutex);
vmw_write(dev_priv, SVGA_REG_GMR_ID, gmr_id);
wmb();
vmw_write(dev_priv, SVGA_REG_GMR_DESCRIPTOR, page_to_pfn(page));
mb();
mutex_unlock(&dev_priv->hw_mutex);
}
/**
* FIXME: Adjust to the ttm lowmem / highmem storage to minimize
* the number of used descriptors.
*/
static unsigned long vmw_gmr_count_descriptors(struct page *pages[],
unsigned long num_pages)
{
unsigned long prev_pfn = ~(0UL);
unsigned long pfn;
unsigned long descriptors = 0;
while (num_pages--) {
pfn = page_to_pfn(*pages++);
if (prev_pfn + 1 != pfn)
++descriptors;
prev_pfn = pfn;
}
return descriptors;
}
int vmw_gmr_bind(struct vmw_private *dev_priv,
struct ttm_buffer_object *bo)
{
struct ttm_tt *ttm = bo->ttm;
unsigned long descriptors;
int ret;
uint32_t id;
struct list_head desc_pages;
if (!(dev_priv->capabilities & SVGA_CAP_GMR))
return -EINVAL;
ret = ttm_tt_populate(ttm);
if (unlikely(ret != 0))
return ret;
descriptors = vmw_gmr_count_descriptors(ttm->pages, ttm->num_pages);
if (unlikely(descriptors > dev_priv->max_gmr_descriptors))
return -EINVAL;
INIT_LIST_HEAD(&desc_pages);
ret = vmw_gmr_build_descriptors(&desc_pages, ttm->pages,
ttm->num_pages);
if (unlikely(ret != 0))
return ret;
ret = vmw_gmr_id_alloc(dev_priv, &id);
if (unlikely(ret != 0))
goto out_no_id;
vmw_gmr_fire_descriptors(dev_priv, id, &desc_pages);
vmw_gmr_free_descriptors(&desc_pages);
vmw_dmabuf_set_gmr(bo, id);
return 0;
out_no_id:
vmw_gmr_free_descriptors(&desc_pages);
return ret;
}
void vmw_gmr_unbind(struct vmw_private *dev_priv, int gmr_id)
{
mutex_lock(&dev_priv->hw_mutex);
vmw_write(dev_priv, SVGA_REG_GMR_ID, gmr_id);
wmb();
vmw_write(dev_priv, SVGA_REG_GMR_DESCRIPTOR, 0);
mb();
mutex_unlock(&dev_priv->hw_mutex);
}