Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752884AbaFXJ4s (ORCPT ); Tue, 24 Jun 2014 05:56:48 -0400 Received: from hqemgate14.nvidia.com ([216.228.121.143]:9510 "EHLO hqemgate14.nvidia.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752608AbaFXJ4W (ORCPT ); Tue, 24 Jun 2014 05:56:22 -0400 X-PGP-Universal: processed; by hqnvupgp08.nvidia.com on Tue, 24 Jun 2014 02:50:18 -0700 From: Alexandre Courbot To: David Airlie , Ben Skeggs , Lucas Stach , Thierry Reding CC: , , , , , , Alexandre Courbot Subject: [PATCH v2 2/3] drm/ttm: introduce dma cache sync helpers Date: Tue, 24 Jun 2014 18:54:26 +0900 Message-ID: <1403603667-11302-3-git-send-email-acourbot@nvidia.com> X-Mailer: git-send-email 2.0.0 In-Reply-To: <1403603667-11302-1-git-send-email-acourbot@nvidia.com> References: <1403603667-11302-1-git-send-email-acourbot@nvidia.com> X-NVConfidentiality: public MIME-Version: 1.0 Content-Type: text/plain Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Lucas Stach On architectures for which access to GPU memory is non-coherent, caches need to be flushed and invalidated explicitly at the appropriate places. Introduce two small helpers to make things easy for TTM-based drivers. Signed-off-by: Lucas Stach Signed-off-by: Alexandre Courbot --- drivers/gpu/drm/ttm/ttm_tt.c | 25 +++++++++++++++++++++++++ include/drm/ttm/ttm_bo_driver.h | 28 ++++++++++++++++++++++++++++ 2 files changed, 53 insertions(+) diff --git a/drivers/gpu/drm/ttm/ttm_tt.c b/drivers/gpu/drm/ttm/ttm_tt.c index 75f319090043..66c16ad35f70 100644 --- a/drivers/gpu/drm/ttm/ttm_tt.c +++ b/drivers/gpu/drm/ttm/ttm_tt.c @@ -38,6 +38,7 @@ #include #include #include +#include #include #include #include @@ -248,6 +249,30 @@ void ttm_dma_tt_fini(struct ttm_dma_tt *ttm_dma) } EXPORT_SYMBOL(ttm_dma_tt_fini); +void ttm_dma_tt_cache_sync_for_device(struct ttm_dma_tt *ttm_dma, + struct device *dev) +{ + unsigned long i; + + for (i = 0; i < ttm_dma->ttm.num_pages; i++) { + dma_sync_single_for_device(dev, ttm_dma->dma_address[i], + PAGE_SIZE, DMA_TO_DEVICE); + } +} +EXPORT_SYMBOL(ttm_dma_tt_cache_sync_for_device); + +void ttm_dma_tt_cache_sync_for_cpu(struct ttm_dma_tt *ttm_dma, + struct device *dev) +{ + unsigned long i; + + for (i = 0; i < ttm_dma->ttm.num_pages; i++) { + dma_sync_single_for_cpu(dev, ttm_dma->dma_address[i], + PAGE_SIZE, DMA_FROM_DEVICE); + } +} +EXPORT_SYMBOL(ttm_dma_tt_cache_sync_for_cpu); + void ttm_tt_unbind(struct ttm_tt *ttm) { int ret; diff --git a/include/drm/ttm/ttm_bo_driver.h b/include/drm/ttm/ttm_bo_driver.h index a5183da3ef92..52fb709568fc 100644 --- a/include/drm/ttm/ttm_bo_driver.h +++ b/include/drm/ttm/ttm_bo_driver.h @@ -41,6 +41,7 @@ #include #include #include +#include struct ttm_backend_func { /** @@ -690,6 +691,33 @@ extern int ttm_tt_swapout(struct ttm_tt *ttm, */ extern void ttm_tt_unpopulate(struct ttm_tt *ttm); +/** + * ttm_dma_tt_cache_sync_for_device: + * + * @ttm A struct ttm_tt of the type returned by ttm_dma_tt_init. + * @dev A struct device representing the device to which to sync. + * + * This function will flush the CPU caches on arches where snooping in the + * TT is not available. On fully coherent arches this will turn into an (almost) + * noop. This makes sure that data written by the CPU is visible to the device. + */ +extern void ttm_dma_tt_cache_sync_for_device(struct ttm_dma_tt *ttm_dma, + struct device *dev); + +/** + * ttm_dma_tt_cache_sync_for_cpu: + * + * @ttm A struct ttm_tt of the type returned by ttm_dma_tt_init. + * @dev A struct device representing the device from which to sync. + * + * This function will invalidate the CPU caches on arches where snooping in the + * TT is not available. On fully coherent arches this will turn into an (almost) + * noop. This makes sure that the CPU does not read any stale cached or + * prefetched data. + */ +extern void ttm_dma_tt_cache_sync_for_cpu(struct ttm_dma_tt *ttm_dma, + struct device *dev); + /* * ttm_bo.c */ -- 2.0.0 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/