From df06b759f2cf4690fa9991edb1504ba39932b2bb Mon Sep 17 00:00:00 2001 From: Thierry Reding Date: Thu, 26 Jun 2014 21:41:53 +0200 Subject: drm/tegra: Add IOMMU support When an IOMMU device is available on the platform bus, allocate an IOMMU domain and attach the display controllers to it. The display controllers can then scan out non-contiguous buffers by mapping them through the IOMMU. Signed-off-by: Thierry Reding --- drivers/gpu/drm/tegra/drm.c | 24 ++++++++++++++++++++++++ 1 file changed, 24 insertions(+) (limited to 'drivers/gpu/drm/tegra/drm.c') diff --git a/drivers/gpu/drm/tegra/drm.c b/drivers/gpu/drm/tegra/drm.c index e1632fb03a89..6c9df794b3be 100644 --- a/drivers/gpu/drm/tegra/drm.c +++ b/drivers/gpu/drm/tegra/drm.c @@ -8,6 +8,7 @@ */ #include +#include #include "drm.h" #include "gem.h" @@ -33,6 +34,17 @@ static int tegra_drm_load(struct drm_device *drm, unsigned long flags) if (!tegra) return -ENOMEM; + if (iommu_present(&platform_bus_type)) { + tegra->domain = iommu_domain_alloc(&platform_bus_type); + if (IS_ERR(tegra->domain)) { + err = PTR_ERR(tegra->domain); + goto free; + } + + DRM_DEBUG("IOMMU context initialized\n"); + drm_mm_init(&tegra->mm, 0, SZ_2G); + } + mutex_init(&tegra->clients_lock); INIT_LIST_HEAD(&tegra->clients); drm->dev_private = tegra; @@ -76,6 +88,12 @@ fbdev: tegra_drm_fb_free(drm); config: drm_mode_config_cleanup(drm); + + if (tegra->domain) { + iommu_domain_free(tegra->domain); + drm_mm_takedown(&tegra->mm); + } +free: kfree(tegra); return err; } @@ -83,6 +101,7 @@ config: static int tegra_drm_unload(struct drm_device *drm) { struct host1x_device *device = to_host1x_device(drm->dev); + struct tegra_drm *tegra = drm->dev_private; int err; drm_kms_helper_poll_fini(drm); @@ -94,6 +113,11 @@ static int tegra_drm_unload(struct drm_device *drm) if (err < 0) return err; + if (tegra->domain) { + iommu_domain_free(tegra->domain); + drm_mm_takedown(&tegra->mm); + } + return 0; } -- cgit