1 files changed, 299 insertions, 0 deletions
diff --git a/drivers/gpu/drm/etnaviv/etnaviv_mmu.c b/drivers/gpu/drm/etnaviv/etnaviv_mmu.c
new file mode 100644
index 000000000000..6743bc648dc8
--- /dev/null
+++ b/drivers/gpu/drm/etnaviv/etnaviv_mmu.c
@@ -0,0 +1,299 @@
+/*
+ * Copyright (C) 2015 Etnaviv Project
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published by
+ * the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include "etnaviv_drv.h"
+#include "etnaviv_gem.h"
+#include "etnaviv_gpu.h"
+#include "etnaviv_mmu.h"
+
+static int etnaviv_fault_handler(struct iommu_domain *iommu, struct device *dev,
+		unsigned long iova, int flags, void *arg)
+{
+	DBG("*** fault: iova=%08lx, flags=%d", iova, flags);
+	return 0;
+}
+
+int etnaviv_iommu_map(struct etnaviv_iommu *iommu, u32 iova,
+		struct sg_table *sgt, unsigned len, int prot)
+{
+	struct iommu_domain *domain = iommu->domain;
+	struct scatterlist *sg;
+	unsigned int da = iova;
+	unsigned int i, j;
+	int ret;
+
+	if (!domain || !sgt)
+		return -EINVAL;
+
+	for_each_sg(sgt->sgl, sg, sgt->nents, i) {
+		u32 pa = sg_dma_address(sg) - sg->offset;
+		size_t bytes = sg_dma_len(sg) + sg->offset;
+
+		VERB("map[%d]: %08x %08x(%zx)", i, iova, pa, bytes);
+
+		ret = iommu_map(domain, da, pa, bytes, prot);
+		if (ret)
+			goto fail;
+
+		da += bytes;
+	}
+
+	return 0;
+
+fail:
+	da = iova;
+
+	for_each_sg(sgt->sgl, sg, i, j) {
+		size_t bytes = sg_dma_len(sg) + sg->offset;
+
+		iommu_unmap(domain, da, bytes);
+		da += bytes;
+	}
+	return ret;
+}
+
+int etnaviv_iommu_unmap(struct etnaviv_iommu *iommu, u32 iova,
+		struct sg_table *sgt, unsigned len)
+{
+	struct iommu_domain *domain = iommu->domain;
+	struct scatterlist *sg;
+	unsigned int da = iova;
+	int i;
+
+	for_each_sg(sgt->sgl, sg, sgt->nents, i) {
+		size_t bytes = sg_dma_len(sg) + sg->offset;
+		size_t unmapped;
+
+		unmapped = iommu_unmap(domain, da, bytes);
+		if (unmapped < bytes)
+			return unmapped;
+
+		VERB("unmap[%d]: %08x(%zx)", i, iova, bytes);
+
+		BUG_ON(!PAGE_ALIGNED(bytes));
+
+		da += bytes;
+	}
+
+	return 0;
+}
+
+static void etnaviv_iommu_remove_mapping(struct etnaviv_iommu *mmu,
+	struct etnaviv_vram_mapping *mapping)
+{
+	struct etnaviv_gem_object *etnaviv_obj = mapping->object;
+
+	etnaviv_iommu_unmap(mmu, mapping->vram_node.start,
+			    etnaviv_obj->sgt, etnaviv_obj->base.size);
+	drm_mm_remove_node(&mapping->vram_node);
+}
+
+int etnaviv_iommu_map_gem(struct etnaviv_iommu *mmu,
+	struct etnaviv_gem_object *etnaviv_obj, u32 memory_base,
+	struct etnaviv_vram_mapping *mapping)
+{
+	struct etnaviv_vram_mapping *free = NULL;
+	struct sg_table *sgt = etnaviv_obj->sgt;
+	struct drm_mm_node *node;
+	int ret;
+
+	lockdep_assert_held(&etnaviv_obj->lock);
+
+	mutex_lock(&mmu->lock);
+
+	/* v1 MMU can optimize single entry (contiguous) scatterlists */
+	if (sgt->nents == 1 && !(etnaviv_obj->flags & ETNA_BO_FORCE_MMU)) {
+		u32 iova;
+
+		iova = sg_dma_address(sgt->sgl) - memory_base;
+		if (iova < 0x80000000 - sg_dma_len(sgt->sgl)) {
+			mapping->iova = iova;
+			list_add_tail(&mapping->mmu_node, &mmu->mappings);
+			mutex_unlock(&mmu->lock);
+			return 0;
+		}
+	}
+
+	node = &mapping->vram_node;
+	while (1) {
+		struct etnaviv_vram_mapping *m, *n;
+		struct list_head list;
+		bool found;
+
+		ret = drm_mm_insert_node_in_range(&mmu->mm, node,
+			etnaviv_obj->base.size, 0, mmu->last_iova, ~0UL,
+			DRM_MM_SEARCH_DEFAULT);
+
+		if (ret != -ENOSPC)
+			break;
+
+		/*
+		 * If we did not search from the start of the MMU region,
+		 * try again in case there are free slots.
+		 */
+		if (mmu->last_iova) {
+			mmu->last_iova = 0;
+			mmu->need_flush = true;
+			continue;
+		}
+
+		/* Try to retire some entries */
+		drm_mm_init_scan(&mmu->mm, etnaviv_obj->base.size, 0, 0);
+
+		found = 0;
+		INIT_LIST_HEAD(&list);
+		list_for_each_entry(free, &mmu->mappings, mmu_node) {
+			/* If this vram node has not been used, skip this. */
+			if (!free->vram_node.mm)
+				continue;
+
+			/*
+			 * If the iova is pinned, then it's in-use,
+			 * so we must keep its mapping.
+			 */
+			if (free->use)
+				continue;
+
+			list_add(&free->scan_node, &list);
+			if (drm_mm_scan_add_block(&free->vram_node)) {
+				found = true;
+				break;
+			}
+		}
+
+		if (!found) {
+			/* Nothing found, clean up and fail */
+			list_for_each_entry_safe(m, n, &list, scan_node)
+				BUG_ON(drm_mm_scan_remove_block(&m->vram_node));
+			break;
+		}
+
+		/*
+		 * drm_mm does not allow any other operations while
+		 * scanning, so we have to remove all blocks first.
+		 * If drm_mm_scan_remove_block() returns false, we
+		 * can leave the block pinned.
+		 */
+		list_for_each_entry_safe(m, n, &list, scan_node)
+			if (!drm_mm_scan_remove_block(&m->vram_node))
+				list_del_init(&m->scan_node);
+
+		/*
+		 * Unmap the blocks which need to be reaped from the MMU.
+		 * Clear the mmu pointer to prevent the get_iova finding
+		 * this mapping.
+		 */
+		list_for_each_entry_safe(m, n, &list, scan_node) {
+			etnaviv_iommu_remove_mapping(mmu, m);
+			m->mmu = NULL;
+			list_del_init(&m->mmu_node);
+			list_del_init(&m->scan_node);
+		}
+
+		/*
+		 * We removed enough mappings so that the new allocation will
+		 * succeed.  Ensure that the MMU will be flushed before the
+		 * associated commit requesting this mapping, and retry the
+		 * allocation one more time.
+		 */
+		mmu->need_flush = true;
+	}
+
+	if (ret < 0) {
+		mutex_unlock(&mmu->lock);
+		return ret;
+	}
+
+	mmu->last_iova = node->start + etnaviv_obj->base.size;
+	mapping->iova = node->start;
+	ret = etnaviv_iommu_map(mmu, node->start, sgt, etnaviv_obj->base.size,
+				IOMMU_READ | IOMMU_WRITE);
+
+	if (ret < 0) {
+		drm_mm_remove_node(node);
+		mutex_unlock(&mmu->lock);
+		return ret;
+	}
+
+	list_add_tail(&mapping->mmu_node, &mmu->mappings);
+	mutex_unlock(&mmu->lock);
+
+	return ret;
+}
+
+void etnaviv_iommu_unmap_gem(struct etnaviv_iommu *mmu,
+	struct etnaviv_vram_mapping *mapping)
+{
+	WARN_ON(mapping->use);
+
+	mutex_lock(&mmu->lock);
+
+	/* If the vram node is on the mm, unmap and remove the node */
+	if (mapping->vram_node.mm == &mmu->mm)
+		etnaviv_iommu_remove_mapping(mmu, mapping);
+
+	list_del(&mapping->mmu_node);
+	mutex_unlock(&mmu->lock);
+}
+
+void etnaviv_iommu_destroy(struct etnaviv_iommu *mmu)
+{
+	drm_mm_takedown(&mmu->mm);
+	iommu_domain_free(mmu->domain);
+	kfree(mmu);
+}
+
+struct etnaviv_iommu *etnaviv_iommu_new(struct etnaviv_gpu *gpu,
+	struct iommu_domain *domain, enum etnaviv_iommu_version version)
+{
+	struct etnaviv_iommu *mmu;
+
+	mmu = kzalloc(sizeof(*mmu), GFP_KERNEL);
+	if (!mmu)
+		return ERR_PTR(-ENOMEM);
+
+	mmu->domain = domain;
+	mmu->gpu = gpu;
+	mmu->version = version;
+	mutex_init(&mmu->lock);
+	INIT_LIST_HEAD(&mmu->mappings);
+
+	drm_mm_init(&mmu->mm, domain->geometry.aperture_start,
+		    domain->geometry.aperture_end -
+		      domain->geometry.aperture_start + 1);
+
+	iommu_set_fault_handler(domain, etnaviv_fault_handler, gpu->dev);
+
+	return mmu;
+}
+
+size_t etnaviv_iommu_dump_size(struct etnaviv_iommu *iommu)
+{
+	struct etnaviv_iommu_ops *ops;
+
+	ops = container_of(iommu->domain->ops, struct etnaviv_iommu_ops, ops);
+
+	return ops->dump_size(iommu->domain);
+}
+
+void etnaviv_iommu_dump(struct etnaviv_iommu *iommu, void *buf)
+{
+	struct etnaviv_iommu_ops *ops;
+
+	ops = container_of(iommu->domain->ops, struct etnaviv_iommu_ops, ops);
+
+	ops->dump(iommu->domain, buf);
+}