Add the rt linux 4.1.3-rt3 as base
[kvmfornfv.git] / kernel / drivers / gpu / drm / exynos / exynos_drm_dmabuf.c
diff --git a/kernel/drivers/gpu/drm/exynos/exynos_drm_dmabuf.c b/kernel/drivers/gpu/drm/exynos/exynos_drm_dmabuf.c
new file mode 100644 (file)
index 0000000..cd485c0
--- /dev/null
@@ -0,0 +1,286 @@
+/* exynos_drm_dmabuf.c
+ *
+ * Copyright (c) 2012 Samsung Electronics Co., Ltd.
+ * Author: Inki Dae <inki.dae@samsung.com>
+ *
+ * This program is free software; you can redistribute  it and/or modify it
+ * under  the terms of  the GNU General  Public License as published by the
+ * Free Software Foundation;  either version 2 of the  License, or (at your
+ * option) any later version.
+ */
+
+#include <drm/drmP.h>
+#include <drm/exynos_drm.h>
+#include "exynos_drm_dmabuf.h"
+#include "exynos_drm_drv.h"
+#include "exynos_drm_gem.h"
+
+#include <linux/dma-buf.h>
+
+struct exynos_drm_dmabuf_attachment {
+       struct sg_table sgt;
+       enum dma_data_direction dir;
+       bool is_mapped;
+};
+
+static struct exynos_drm_gem_obj *dma_buf_to_obj(struct dma_buf *buf)
+{
+       return to_exynos_gem_obj(buf->priv);
+}
+
+static int exynos_gem_attach_dma_buf(struct dma_buf *dmabuf,
+                                       struct device *dev,
+                                       struct dma_buf_attachment *attach)
+{
+       struct exynos_drm_dmabuf_attachment *exynos_attach;
+
+       exynos_attach = kzalloc(sizeof(*exynos_attach), GFP_KERNEL);
+       if (!exynos_attach)
+               return -ENOMEM;
+
+       exynos_attach->dir = DMA_NONE;
+       attach->priv = exynos_attach;
+
+       return 0;
+}
+
+static void exynos_gem_detach_dma_buf(struct dma_buf *dmabuf,
+                                       struct dma_buf_attachment *attach)
+{
+       struct exynos_drm_dmabuf_attachment *exynos_attach = attach->priv;
+       struct sg_table *sgt;
+
+       if (!exynos_attach)
+               return;
+
+       sgt = &exynos_attach->sgt;
+
+       if (exynos_attach->dir != DMA_NONE)
+               dma_unmap_sg(attach->dev, sgt->sgl, sgt->nents,
+                               exynos_attach->dir);
+
+       sg_free_table(sgt);
+       kfree(exynos_attach);
+       attach->priv = NULL;
+}
+
+static struct sg_table *
+               exynos_gem_map_dma_buf(struct dma_buf_attachment *attach,
+                                       enum dma_data_direction dir)
+{
+       struct exynos_drm_dmabuf_attachment *exynos_attach = attach->priv;
+       struct exynos_drm_gem_obj *gem_obj = dma_buf_to_obj(attach->dmabuf);
+       struct drm_device *dev = gem_obj->base.dev;
+       struct exynos_drm_gem_buf *buf;
+       struct scatterlist *rd, *wr;
+       struct sg_table *sgt = NULL;
+       unsigned int i;
+       int nents, ret;
+
+       /* just return current sgt if already requested. */
+       if (exynos_attach->dir == dir && exynos_attach->is_mapped)
+               return &exynos_attach->sgt;
+
+       buf = gem_obj->buffer;
+       if (!buf) {
+               DRM_ERROR("buffer is null.\n");
+               return ERR_PTR(-ENOMEM);
+       }
+
+       sgt = &exynos_attach->sgt;
+
+       ret = sg_alloc_table(sgt, buf->sgt->orig_nents, GFP_KERNEL);
+       if (ret) {
+               DRM_ERROR("failed to alloc sgt.\n");
+               return ERR_PTR(-ENOMEM);
+       }
+
+       mutex_lock(&dev->struct_mutex);
+
+       rd = buf->sgt->sgl;
+       wr = sgt->sgl;
+       for (i = 0; i < sgt->orig_nents; ++i) {
+               sg_set_page(wr, sg_page(rd), rd->length, rd->offset);
+               rd = sg_next(rd);
+               wr = sg_next(wr);
+       }
+
+       if (dir != DMA_NONE) {
+               nents = dma_map_sg(attach->dev, sgt->sgl, sgt->orig_nents, dir);
+               if (!nents) {
+                       DRM_ERROR("failed to map sgl with iommu.\n");
+                       sg_free_table(sgt);
+                       sgt = ERR_PTR(-EIO);
+                       goto err_unlock;
+               }
+       }
+
+       exynos_attach->is_mapped = true;
+       exynos_attach->dir = dir;
+       attach->priv = exynos_attach;
+
+       DRM_DEBUG_PRIME("buffer size = 0x%lx\n", buf->size);
+
+err_unlock:
+       mutex_unlock(&dev->struct_mutex);
+       return sgt;
+}
+
+static void exynos_gem_unmap_dma_buf(struct dma_buf_attachment *attach,
+                                               struct sg_table *sgt,
+                                               enum dma_data_direction dir)
+{
+       /* Nothing to do. */
+}
+
+static void *exynos_gem_dmabuf_kmap_atomic(struct dma_buf *dma_buf,
+                                               unsigned long page_num)
+{
+       /* TODO */
+
+       return NULL;
+}
+
+static void exynos_gem_dmabuf_kunmap_atomic(struct dma_buf *dma_buf,
+                                               unsigned long page_num,
+                                               void *addr)
+{
+       /* TODO */
+}
+
+static void *exynos_gem_dmabuf_kmap(struct dma_buf *dma_buf,
+                                       unsigned long page_num)
+{
+       /* TODO */
+
+       return NULL;
+}
+
+static void exynos_gem_dmabuf_kunmap(struct dma_buf *dma_buf,
+                                       unsigned long page_num, void *addr)
+{
+       /* TODO */
+}
+
+static int exynos_gem_dmabuf_mmap(struct dma_buf *dma_buf,
+       struct vm_area_struct *vma)
+{
+       return -ENOTTY;
+}
+
+static struct dma_buf_ops exynos_dmabuf_ops = {
+       .attach                 = exynos_gem_attach_dma_buf,
+       .detach                 = exynos_gem_detach_dma_buf,
+       .map_dma_buf            = exynos_gem_map_dma_buf,
+       .unmap_dma_buf          = exynos_gem_unmap_dma_buf,
+       .kmap                   = exynos_gem_dmabuf_kmap,
+       .kmap_atomic            = exynos_gem_dmabuf_kmap_atomic,
+       .kunmap                 = exynos_gem_dmabuf_kunmap,
+       .kunmap_atomic          = exynos_gem_dmabuf_kunmap_atomic,
+       .mmap                   = exynos_gem_dmabuf_mmap,
+       .release                = drm_gem_dmabuf_release,
+};
+
+struct dma_buf *exynos_dmabuf_prime_export(struct drm_device *drm_dev,
+                               struct drm_gem_object *obj, int flags)
+{
+       struct exynos_drm_gem_obj *exynos_gem_obj = to_exynos_gem_obj(obj);
+       DEFINE_DMA_BUF_EXPORT_INFO(exp_info);
+
+       exp_info.ops = &exynos_dmabuf_ops;
+       exp_info.size = exynos_gem_obj->base.size;
+       exp_info.flags = flags;
+       exp_info.priv = obj;
+
+       return dma_buf_export(&exp_info);
+}
+
+struct drm_gem_object *exynos_dmabuf_prime_import(struct drm_device *drm_dev,
+                               struct dma_buf *dma_buf)
+{
+       struct dma_buf_attachment *attach;
+       struct sg_table *sgt;
+       struct scatterlist *sgl;
+       struct exynos_drm_gem_obj *exynos_gem_obj;
+       struct exynos_drm_gem_buf *buffer;
+       int ret;
+
+       /* is this one of own objects? */
+       if (dma_buf->ops == &exynos_dmabuf_ops) {
+               struct drm_gem_object *obj;
+
+               obj = dma_buf->priv;
+
+               /* is it from our device? */
+               if (obj->dev == drm_dev) {
+                       /*
+                        * Importing dmabuf exported from out own gem increases
+                        * refcount on gem itself instead of f_count of dmabuf.
+                        */
+                       drm_gem_object_reference(obj);
+                       return obj;
+               }
+       }
+
+       attach = dma_buf_attach(dma_buf, drm_dev->dev);
+       if (IS_ERR(attach))
+               return ERR_PTR(-EINVAL);
+
+       get_dma_buf(dma_buf);
+
+       sgt = dma_buf_map_attachment(attach, DMA_BIDIRECTIONAL);
+       if (IS_ERR(sgt)) {
+               ret = PTR_ERR(sgt);
+               goto err_buf_detach;
+       }
+
+       buffer = kzalloc(sizeof(*buffer), GFP_KERNEL);
+       if (!buffer) {
+               ret = -ENOMEM;
+               goto err_unmap_attach;
+       }
+
+       exynos_gem_obj = exynos_drm_gem_init(drm_dev, dma_buf->size);
+       if (!exynos_gem_obj) {
+               ret = -ENOMEM;
+               goto err_free_buffer;
+       }
+
+       sgl = sgt->sgl;
+
+       buffer->size = dma_buf->size;
+       buffer->dma_addr = sg_dma_address(sgl);
+
+       if (sgt->nents == 1) {
+               /* always physically continuous memory if sgt->nents is 1. */
+               exynos_gem_obj->flags |= EXYNOS_BO_CONTIG;
+       } else {
+               /*
+                * this case could be CONTIG or NONCONTIG type but for now
+                * sets NONCONTIG.
+                * TODO. we have to find a way that exporter can notify
+                * the type of its own buffer to importer.
+                */
+               exynos_gem_obj->flags |= EXYNOS_BO_NONCONTIG;
+       }
+
+       exynos_gem_obj->buffer = buffer;
+       buffer->sgt = sgt;
+       exynos_gem_obj->base.import_attach = attach;
+
+       DRM_DEBUG_PRIME("dma_addr = %pad, size = 0x%lx\n", &buffer->dma_addr,
+                                                               buffer->size);
+
+       return &exynos_gem_obj->base;
+
+err_free_buffer:
+       kfree(buffer);
+       buffer = NULL;
+err_unmap_attach:
+       dma_buf_unmap_attachment(attach, sgt, DMA_BIDIRECTIONAL);
+err_buf_detach:
+       dma_buf_detach(dma_buf, attach);
+       dma_buf_put(dma_buf);
+
+       return ERR_PTR(ret);
+}