diff mbox

drm/cache: Implement drm_clflush_*() for ARM

Message ID 1418229530-21865-1-git-send-email-thierry.reding@gmail.com (mailing list archive)
State New, archived
Headers show

Commit Message

Thierry Reding Dec. 10, 2014, 4:38 p.m. UTC
From: Thierry Reding <treding@nvidia.com>

Add implementations for drm_clflush_*() on ARM by borrowing code from
the DMA mapping API implementation. Unfortunately ARM doesn't export an
API to flush caches on a page by page basis, so this replicates most of
the code.

Signed-off-by: Thierry Reding <treding@nvidia.com>
---
 drivers/gpu/drm/drm_cache.c | 45 +++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 45 insertions(+)

Comments

Rob Clark Dec. 10, 2014, 5:49 p.m. UTC | #1
On Wed, Dec 10, 2014 at 11:38 AM, Thierry Reding
<thierry.reding@gmail.com> wrote:
> From: Thierry Reding <treding@nvidia.com>
>
> Add implementations for drm_clflush_*() on ARM by borrowing code from
> the DMA mapping API implementation. Unfortunately ARM doesn't export an
> API to flush caches on a page by page basis, so this replicates most of
> the code.
>

Makes for a nice little simplification in msm_gem, now that I can use
clflush helper.  And if ARM does gain a better API it would be nice to
just update the helper, rather than each driver.

Reviewed&Tested-by: Rob Clark <robdclark@gmail.com>


> Signed-off-by: Thierry Reding <treding@nvidia.com>
> ---
>  drivers/gpu/drm/drm_cache.c | 45 +++++++++++++++++++++++++++++++++++++++++++++
>  1 file changed, 45 insertions(+)
>
> diff --git a/drivers/gpu/drm/drm_cache.c b/drivers/gpu/drm/drm_cache.c
> index a6b690626a6b..fca0b8994c77 100644
> --- a/drivers/gpu/drm/drm_cache.c
> +++ b/drivers/gpu/drm/drm_cache.c
> @@ -72,6 +72,41 @@ drm_clflush_ipi_handler(void *null)
>  }
>  #endif
>
> +#if defined(CONFIG_ARM)
> +
> +#include <asm/cacheflush.h>
> +#include <asm/cachetype.h>
> +#include <asm/highmem.h>
> +#include <asm/outercache.h>
> +
> +static void drm_clflush_page(struct page *page)
> +{
> +       enum dma_data_direction dir = DMA_TO_DEVICE;
> +       phys_addr_t phys = page_to_phys(page);
> +       size_t size = PAGE_SIZE;
> +       void *virt;
> +
> +       if (PageHighMem(page)) {
> +               if (cache_is_vipt_nonaliasing()) {
> +                       virt = kmap_atomic(page);
> +                       dmac_map_area(virt, size, dir);
> +                       kunmap_atomic(virt);
> +               } else {
> +                       virt = kmap_high_get(page);
> +                       if (virt) {
> +                               dmac_map_area(virt, size, dir);
> +                               kunmap_high(page);
> +                       }
> +               }
> +       } else {
> +               virt = page_address(page);
> +               dmac_map_area(virt, size, dir);
> +       }
> +
> +       outer_flush_range(phys, phys + PAGE_SIZE);
> +}
> +#endif
> +
>  void
>  drm_clflush_pages(struct page *pages[], unsigned long num_pages)
>  {
> @@ -99,6 +134,11 @@ drm_clflush_pages(struct page *pages[], unsigned long num_pages)
>                                    (unsigned long)page_virtual + PAGE_SIZE);
>                 kunmap_atomic(page_virtual);
>         }
> +#elif defined(CONFIG_ARM)
> +       unsigned long i;
> +
> +       for (i = 0; i < num_pages; i++)
> +               drm_clflush_page(pages[i]);
>  #else
>         printk(KERN_ERR "Architecture has no drm_cache.c support\n");
>         WARN_ON_ONCE(1);
> @@ -123,6 +163,11 @@ drm_clflush_sg(struct sg_table *st)
>
>         if (on_each_cpu(drm_clflush_ipi_handler, NULL, 1) != 0)
>                 printk(KERN_ERR "Timed out waiting for cache flush.\n");
> +#elif defined(CONFIG_ARM)
> +       struct sg_page_iter sg_iter;
> +
> +       for_each_sg_page(st->sgl, &sg_iter, st->nents, 0)
> +               drm_clflush_page(sg_page_iter_page(&sg_iter));
>  #else
>         printk(KERN_ERR "Architecture has no drm_cache.c support\n");
>         WARN_ON_ONCE(1);
> --
> 2.1.3
>
diff mbox

Patch

diff --git a/drivers/gpu/drm/drm_cache.c b/drivers/gpu/drm/drm_cache.c
index a6b690626a6b..fca0b8994c77 100644
--- a/drivers/gpu/drm/drm_cache.c
+++ b/drivers/gpu/drm/drm_cache.c
@@ -72,6 +72,41 @@  drm_clflush_ipi_handler(void *null)
 }
 #endif
 
+#if defined(CONFIG_ARM)
+
+#include <asm/cacheflush.h>
+#include <asm/cachetype.h>
+#include <asm/highmem.h>
+#include <asm/outercache.h>
+
+static void drm_clflush_page(struct page *page)
+{
+	enum dma_data_direction dir = DMA_TO_DEVICE;
+	phys_addr_t phys = page_to_phys(page);
+	size_t size = PAGE_SIZE;
+	void *virt;
+
+	if (PageHighMem(page)) {
+		if (cache_is_vipt_nonaliasing()) {
+			virt = kmap_atomic(page);
+			dmac_map_area(virt, size, dir);
+			kunmap_atomic(virt);
+		} else {
+			virt = kmap_high_get(page);
+			if (virt) {
+				dmac_map_area(virt, size, dir);
+				kunmap_high(page);
+			}
+		}
+	} else {
+		virt = page_address(page);
+		dmac_map_area(virt, size, dir);
+	}
+
+	outer_flush_range(phys, phys + PAGE_SIZE);
+}
+#endif
+
 void
 drm_clflush_pages(struct page *pages[], unsigned long num_pages)
 {
@@ -99,6 +134,11 @@  drm_clflush_pages(struct page *pages[], unsigned long num_pages)
 				   (unsigned long)page_virtual + PAGE_SIZE);
 		kunmap_atomic(page_virtual);
 	}
+#elif defined(CONFIG_ARM)
+	unsigned long i;
+
+	for (i = 0; i < num_pages; i++)
+		drm_clflush_page(pages[i]);
 #else
 	printk(KERN_ERR "Architecture has no drm_cache.c support\n");
 	WARN_ON_ONCE(1);
@@ -123,6 +163,11 @@  drm_clflush_sg(struct sg_table *st)
 
 	if (on_each_cpu(drm_clflush_ipi_handler, NULL, 1) != 0)
 		printk(KERN_ERR "Timed out waiting for cache flush.\n");
+#elif defined(CONFIG_ARM)
+	struct sg_page_iter sg_iter;
+
+	for_each_sg_page(st->sgl, &sg_iter, st->nents, 0)
+		drm_clflush_page(sg_page_iter_page(&sg_iter));
 #else
 	printk(KERN_ERR "Architecture has no drm_cache.c support\n");
 	WARN_ON_ONCE(1);