Re: [PATCH 08/10] drm/gma500: Set page-caching flags in GEM pin/unpin

On Tue, Sep 28, 2021 at 10:44 AM Thomas Zimmermann tzimmermann@suse.de wrote:

Caching of the GEM object's backing pages are unrelated to GTT management. Move the respective calls from GTT code to GEM code.

Signed-off-by: Thomas Zimmermann tzimmermann@suse.de

drivers/gpu/drm/gma500/gem.c | 9 ++++++++- drivers/gpu/drm/gma500/gtt.c | 17 ++--------------- drivers/gpu/drm/gma500/gtt.h | 2 +- 3 files changed, 11 insertions(+), 17 deletions(-)

diff --git a/drivers/gpu/drm/gma500/gem.c b/drivers/gpu/drm/gma500/gem.c index 46209e10dcc2..a88d51a3aa2a 100644 --- a/drivers/gpu/drm/gma500/gem.c +++ b/drivers/gpu/drm/gma500/gem.c @@ -13,6 +13,8 @@

#include <linux/pagemap.h>

+#include <asm/set_memory.h>

#include <drm/drm.h> #include <drm/drm_vma_manager.h>

@@ -39,7 +41,9 @@ int psb_gem_pin(struct gtt_range *gt)

    npages = gt->gem.size / PAGE_SIZE;

•   ret = psb_gtt_insert(dev, gt, 0);
  

•   set_pages_array_wc(pages, npages);
  

•   ret = psb_gtt_insert(dev, gt);
    if (ret)
            goto err_drm_gem_put_pages;
  
  

@@ -80,6 +84,9 @@ void psb_gem_unpin(struct gtt_range *gt) (gpu_base + gt->offset), gt->npage, 0, 0); psb_gtt_remove(dev, gt);

•   /* Reset caching flags */
  

•   set_pages_array_wb(gt->pages, gt->npage);
  

•   drm_gem_put_pages(&gt->gem, gt->pages, true, false);
    gt->pages = NULL;
  
  

diff --git a/drivers/gpu/drm/gma500/gtt.c b/drivers/gpu/drm/gma500/gtt.c index 5d940fdbe6b8..244de618e612 100644 --- a/drivers/gpu/drm/gma500/gtt.c +++ b/drivers/gpu/drm/gma500/gtt.c @@ -7,10 +7,6 @@

•     Alan Cox <alan@linux.intel.com>
  

*/

-#include <linux/shmem_fs.h>

-#include <asm/set_memory.h>

#include "psb_drv.h"

@@ -92,17 +88,15 @@ static u32 __iomem *psb_gtt_entry(struct drm_device *dev, struct gtt_range *r)

• psb_gtt_insert  -       put an object into the GTT
  

• @dev: our DRM device
  

• @r: our GTT range
  

• • @resume: on resume
    

  • Take our preallocated GTT range and insert the GEM object into
    

  • the GTT. This is protected via the gtt mutex which the caller
    

  • must hold.
    

  */

-int psb_gtt_insert(struct drm_device *dev, struct gtt_range *r, int resume) +int psb_gtt_insert(struct drm_device *dev, struct gtt_range *r) { u32 __iomem *gtt_slot; u32 pte;

•   struct page **pages;
    int i;
  
    if (r->pages == NULL) {
  

@@ -113,12 +107,6 @@ int psb_gtt_insert(struct drm_device *dev, struct gtt_range *r, int resume) WARN_ON(r->stolen); /* refcount these maybe ? */

    gtt_slot = psb_gtt_entry(dev, r);

•   pages = r->pages;
  

•   if (!resume) {
  

•           /* Make sure changes are visible to the GPU */
  

•           set_pages_array_wc(pages, r->npage);
  

•   }
  

I don't quite remember why we have this but I suspect something bad happened when setting WC on a page with WC already set. Did you try hibernation?

    /* Write our page entries into the GTT itself */
    for (i = 0; i < r->npage; i++) {

@@ -158,7 +146,6 @@ void psb_gtt_remove(struct drm_device *dev, struct gtt_range *r) for (i = 0; i < r->npage; i++) iowrite32(pte, gtt_slot++); ioread32(gtt_slot - 1);

•   set_pages_array_wb(r->pages, r->npage);
  

}

static void psb_gtt_alloc(struct drm_device *dev) @@ -349,7 +336,7 @@ int psb_gtt_restore(struct drm_device *dev) while (r != NULL) { range = container_of(r, struct gtt_range, resource); if (range->pages) {

•                   psb_gtt_insert(dev, range, 1);
  

•                   psb_gtt_insert(dev, range);
                    size += range->resource.end - range->resource.start;
                    restored++;
            }
  

diff --git a/drivers/gpu/drm/gma500/gtt.h b/drivers/gpu/drm/gma500/gtt.h index 459a03141e8b..7af71617e0c5 100644 --- a/drivers/gpu/drm/gma500/gtt.h +++ b/drivers/gpu/drm/gma500/gtt.h @@ -49,7 +49,7 @@ int psb_gtt_allocate_resource(struct drm_psb_private *pdev, struct resource *res const char *name, resource_size_t size, resource_size_t align, bool stolen, u32 offset[static 1]);

-int psb_gtt_insert(struct drm_device *dev, struct gtt_range *r, int resume); +int psb_gtt_insert(struct drm_device *dev, struct gtt_range *r); void psb_gtt_remove(struct drm_device *dev, struct gtt_range *r);

#endif

2.33.0