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-rw-r--r--sys/dev/drm2/ttm/ttm_bo_util.c658
1 files changed, 658 insertions, 0 deletions
diff --git a/sys/dev/drm2/ttm/ttm_bo_util.c b/sys/dev/drm2/ttm/ttm_bo_util.c
new file mode 100644
index 0000000..139d134
--- /dev/null
+++ b/sys/dev/drm2/ttm/ttm_bo_util.c
@@ -0,0 +1,658 @@
+/**************************************************************************
+ *
+ * Copyright (c) 2007-2009 VMware, Inc., Palo Alto, CA., USA
+ * All Rights Reserved.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the
+ * "Software"), to deal in the Software without restriction, including
+ * without limitation the rights to use, copy, modify, merge, publish,
+ * distribute, sub license, and/or sell copies of the Software, and to
+ * permit persons to whom the Software is furnished to do so, subject to
+ * the following conditions:
+ *
+ * The above copyright notice and this permission notice (including the
+ * next paragraph) shall be included in all copies or substantial portions
+ * of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL
+ * THE COPYRIGHT HOLDERS, AUTHORS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM,
+ * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
+ * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
+ * USE OR OTHER DEALINGS IN THE SOFTWARE.
+ *
+ **************************************************************************/
+/*
+ * Authors: Thomas Hellstrom <thellstrom-at-vmware-dot-com>
+ */
+
+#include <sys/cdefs.h>
+__FBSDID("$FreeBSD$");
+
+#include <dev/drm2/drmP.h>
+#include <dev/drm2/ttm/ttm_bo_driver.h>
+#include <dev/drm2/ttm/ttm_placement.h>
+#include <sys/sf_buf.h>
+
+void ttm_bo_free_old_node(struct ttm_buffer_object *bo)
+{
+ ttm_bo_mem_put(bo, &bo->mem);
+}
+
+int ttm_bo_move_ttm(struct ttm_buffer_object *bo,
+ bool evict,
+ bool no_wait_gpu, struct ttm_mem_reg *new_mem)
+{
+ struct ttm_tt *ttm = bo->ttm;
+ struct ttm_mem_reg *old_mem = &bo->mem;
+ int ret;
+
+ if (old_mem->mem_type != TTM_PL_SYSTEM) {
+ ttm_tt_unbind(ttm);
+ ttm_bo_free_old_node(bo);
+ ttm_flag_masked(&old_mem->placement, TTM_PL_FLAG_SYSTEM,
+ TTM_PL_MASK_MEM);
+ old_mem->mem_type = TTM_PL_SYSTEM;
+ }
+
+ ret = ttm_tt_set_placement_caching(ttm, new_mem->placement);
+ if (unlikely(ret != 0))
+ return ret;
+
+ if (new_mem->mem_type != TTM_PL_SYSTEM) {
+ ret = ttm_tt_bind(ttm, new_mem);
+ if (unlikely(ret != 0))
+ return ret;
+ }
+
+ *old_mem = *new_mem;
+ new_mem->mm_node = NULL;
+
+ return 0;
+}
+
+int ttm_mem_io_lock(struct ttm_mem_type_manager *man, bool interruptible)
+{
+ if (likely(man->io_reserve_fastpath))
+ return 0;
+
+ if (interruptible) {
+ if (sx_xlock_sig(&man->io_reserve_mutex))
+ return (-EINTR);
+ else
+ return (0);
+ }
+
+ sx_xlock(&man->io_reserve_mutex);
+ return 0;
+}
+
+void ttm_mem_io_unlock(struct ttm_mem_type_manager *man)
+{
+ if (likely(man->io_reserve_fastpath))
+ return;
+
+ sx_xunlock(&man->io_reserve_mutex);
+}
+
+static int ttm_mem_io_evict(struct ttm_mem_type_manager *man)
+{
+ struct ttm_buffer_object *bo;
+
+ if (!man->use_io_reserve_lru || list_empty(&man->io_reserve_lru))
+ return -EAGAIN;
+
+ bo = list_first_entry(&man->io_reserve_lru,
+ struct ttm_buffer_object,
+ io_reserve_lru);
+ list_del_init(&bo->io_reserve_lru);
+ ttm_bo_unmap_virtual_locked(bo);
+
+ return 0;
+}
+
+static int ttm_mem_io_reserve(struct ttm_bo_device *bdev,
+ struct ttm_mem_reg *mem)
+{
+ struct ttm_mem_type_manager *man = &bdev->man[mem->mem_type];
+ int ret = 0;
+
+ if (!bdev->driver->io_mem_reserve)
+ return 0;
+ if (likely(man->io_reserve_fastpath))
+ return bdev->driver->io_mem_reserve(bdev, mem);
+
+ if (bdev->driver->io_mem_reserve &&
+ mem->bus.io_reserved_count++ == 0) {
+retry:
+ ret = bdev->driver->io_mem_reserve(bdev, mem);
+ if (ret == -EAGAIN) {
+ ret = ttm_mem_io_evict(man);
+ if (ret == 0)
+ goto retry;
+ }
+ }
+ return ret;
+}
+
+static void ttm_mem_io_free(struct ttm_bo_device *bdev,
+ struct ttm_mem_reg *mem)
+{
+ struct ttm_mem_type_manager *man = &bdev->man[mem->mem_type];
+
+ if (likely(man->io_reserve_fastpath))
+ return;
+
+ if (bdev->driver->io_mem_reserve &&
+ --mem->bus.io_reserved_count == 0 &&
+ bdev->driver->io_mem_free)
+ bdev->driver->io_mem_free(bdev, mem);
+
+}
+
+int ttm_mem_io_reserve_vm(struct ttm_buffer_object *bo)
+{
+ struct ttm_mem_reg *mem = &bo->mem;
+ int ret;
+
+ if (!mem->bus.io_reserved_vm) {
+ struct ttm_mem_type_manager *man =
+ &bo->bdev->man[mem->mem_type];
+
+ ret = ttm_mem_io_reserve(bo->bdev, mem);
+ if (unlikely(ret != 0))
+ return ret;
+ mem->bus.io_reserved_vm = true;
+ if (man->use_io_reserve_lru)
+ list_add_tail(&bo->io_reserve_lru,
+ &man->io_reserve_lru);
+ }
+ return 0;
+}
+
+void ttm_mem_io_free_vm(struct ttm_buffer_object *bo)
+{
+ struct ttm_mem_reg *mem = &bo->mem;
+
+ if (mem->bus.io_reserved_vm) {
+ mem->bus.io_reserved_vm = false;
+ list_del_init(&bo->io_reserve_lru);
+ ttm_mem_io_free(bo->bdev, mem);
+ }
+}
+
+static
+int ttm_mem_reg_ioremap(struct ttm_bo_device *bdev, struct ttm_mem_reg *mem,
+ void **virtual)
+{
+ struct ttm_mem_type_manager *man = &bdev->man[mem->mem_type];
+ int ret;
+ void *addr;
+
+ *virtual = NULL;
+ (void) ttm_mem_io_lock(man, false);
+ ret = ttm_mem_io_reserve(bdev, mem);
+ ttm_mem_io_unlock(man);
+ if (ret || !mem->bus.is_iomem)
+ return ret;
+
+ if (mem->bus.addr) {
+ addr = mem->bus.addr;
+ } else {
+ addr = pmap_mapdev_attr(mem->bus.base + mem->bus.offset,
+ mem->bus.size, (mem->placement & TTM_PL_FLAG_WC) ?
+ VM_MEMATTR_WRITE_COMBINING : VM_MEMATTR_UNCACHEABLE);
+ if (!addr) {
+ (void) ttm_mem_io_lock(man, false);
+ ttm_mem_io_free(bdev, mem);
+ ttm_mem_io_unlock(man);
+ return -ENOMEM;
+ }
+ }
+ *virtual = addr;
+ return 0;
+}
+
+static
+void ttm_mem_reg_iounmap(struct ttm_bo_device *bdev, struct ttm_mem_reg *mem,
+ void *virtual)
+{
+ struct ttm_mem_type_manager *man;
+
+ man = &bdev->man[mem->mem_type];
+
+ if (virtual && mem->bus.addr == NULL)
+ pmap_unmapdev((vm_offset_t)virtual, mem->bus.size);
+ (void) ttm_mem_io_lock(man, false);
+ ttm_mem_io_free(bdev, mem);
+ ttm_mem_io_unlock(man);
+}
+
+static int ttm_copy_io_page(void *dst, void *src, unsigned long page)
+{
+ uint32_t *dstP =
+ (uint32_t *) ((unsigned long)dst + (page << PAGE_SHIFT));
+ uint32_t *srcP =
+ (uint32_t *) ((unsigned long)src + (page << PAGE_SHIFT));
+
+ int i;
+ for (i = 0; i < PAGE_SIZE / sizeof(uint32_t); ++i)
+ /* iowrite32(ioread32(srcP++), dstP++); */
+ *dstP++ = *srcP++;
+ return 0;
+}
+
+static int ttm_copy_io_ttm_page(struct ttm_tt *ttm, void *src,
+ unsigned long page,
+ vm_memattr_t prot)
+{
+ vm_page_t d = ttm->pages[page];
+ void *dst;
+
+ if (!d)
+ return -ENOMEM;
+
+ src = (void *)((unsigned long)src + (page << PAGE_SHIFT));
+
+ /* XXXKIB can't sleep ? */
+ dst = pmap_mapdev_attr(VM_PAGE_TO_PHYS(d), PAGE_SIZE, prot);
+ if (!dst)
+ return -ENOMEM;
+
+ memcpy(dst, src, PAGE_SIZE);
+
+ pmap_unmapdev((vm_offset_t)dst, PAGE_SIZE);
+
+ return 0;
+}
+
+static int ttm_copy_ttm_io_page(struct ttm_tt *ttm, void *dst,
+ unsigned long page,
+ vm_memattr_t prot)
+{
+ vm_page_t s = ttm->pages[page];
+ void *src;
+
+ if (!s)
+ return -ENOMEM;
+
+ dst = (void *)((unsigned long)dst + (page << PAGE_SHIFT));
+ src = pmap_mapdev_attr(VM_PAGE_TO_PHYS(s), PAGE_SIZE, prot);
+ if (!src)
+ return -ENOMEM;
+
+ memcpy(dst, src, PAGE_SIZE);
+
+ pmap_unmapdev((vm_offset_t)src, PAGE_SIZE);
+
+ return 0;
+}
+
+int ttm_bo_move_memcpy(struct ttm_buffer_object *bo,
+ bool evict, bool no_wait_gpu,
+ struct ttm_mem_reg *new_mem)
+{
+ struct ttm_bo_device *bdev = bo->bdev;
+ struct ttm_mem_type_manager *man = &bdev->man[new_mem->mem_type];
+ struct ttm_tt *ttm = bo->ttm;
+ struct ttm_mem_reg *old_mem = &bo->mem;
+ struct ttm_mem_reg old_copy = *old_mem;
+ void *old_iomap;
+ void *new_iomap;
+ int ret;
+ unsigned long i;
+ unsigned long page;
+ unsigned long add = 0;
+ int dir;
+
+ ret = ttm_mem_reg_ioremap(bdev, old_mem, &old_iomap);
+ if (ret)
+ return ret;
+ ret = ttm_mem_reg_ioremap(bdev, new_mem, &new_iomap);
+ if (ret)
+ goto out;
+
+ if (old_iomap == NULL && new_iomap == NULL)
+ goto out2;
+ if (old_iomap == NULL && ttm == NULL)
+ goto out2;
+
+ if (ttm->state == tt_unpopulated) {
+ ret = ttm->bdev->driver->ttm_tt_populate(ttm);
+ if (ret)
+ goto out1;
+ }
+
+ add = 0;
+ dir = 1;
+
+ if ((old_mem->mem_type == new_mem->mem_type) &&
+ (new_mem->start < old_mem->start + old_mem->size)) {
+ dir = -1;
+ add = new_mem->num_pages - 1;
+ }
+
+ for (i = 0; i < new_mem->num_pages; ++i) {
+ page = i * dir + add;
+ if (old_iomap == NULL) {
+ vm_memattr_t prot = ttm_io_prot(old_mem->placement);
+ ret = ttm_copy_ttm_io_page(ttm, new_iomap, page,
+ prot);
+ } else if (new_iomap == NULL) {
+ vm_memattr_t prot = ttm_io_prot(new_mem->placement);
+ ret = ttm_copy_io_ttm_page(ttm, old_iomap, page,
+ prot);
+ } else
+ ret = ttm_copy_io_page(new_iomap, old_iomap, page);
+ if (ret)
+ goto out1;
+ }
+ mb();
+out2:
+ old_copy = *old_mem;
+ *old_mem = *new_mem;
+ new_mem->mm_node = NULL;
+
+ if ((man->flags & TTM_MEMTYPE_FLAG_FIXED) && (ttm != NULL)) {
+ ttm_tt_unbind(ttm);
+ ttm_tt_destroy(ttm);
+ bo->ttm = NULL;
+ }
+
+out1:
+ ttm_mem_reg_iounmap(bdev, old_mem, new_iomap);
+out:
+ ttm_mem_reg_iounmap(bdev, &old_copy, old_iomap);
+ ttm_bo_mem_put(bo, &old_copy);
+ return ret;
+}
+
+MALLOC_DEFINE(M_TTM_TRANSF_OBJ, "ttm_transf_obj", "TTM Transfer Objects");
+
+static void ttm_transfered_destroy(struct ttm_buffer_object *bo)
+{
+ free(bo, M_TTM_TRANSF_OBJ);
+}
+
+/**
+ * ttm_buffer_object_transfer
+ *
+ * @bo: A pointer to a struct ttm_buffer_object.
+ * @new_obj: A pointer to a pointer to a newly created ttm_buffer_object,
+ * holding the data of @bo with the old placement.
+ *
+ * This is a utility function that may be called after an accelerated move
+ * has been scheduled. A new buffer object is created as a placeholder for
+ * the old data while it's being copied. When that buffer object is idle,
+ * it can be destroyed, releasing the space of the old placement.
+ * Returns:
+ * !0: Failure.
+ */
+
+static int ttm_buffer_object_transfer(struct ttm_buffer_object *bo,
+ struct ttm_buffer_object **new_obj)
+{
+ struct ttm_buffer_object *fbo;
+ struct ttm_bo_device *bdev = bo->bdev;
+ struct ttm_bo_driver *driver = bdev->driver;
+
+ fbo = malloc(sizeof(*fbo), M_TTM_TRANSF_OBJ, M_ZERO | M_WAITOK);
+ *fbo = *bo;
+
+ /**
+ * Fix up members that we shouldn't copy directly:
+ * TODO: Explicit member copy would probably be better here.
+ */
+
+ INIT_LIST_HEAD(&fbo->ddestroy);
+ INIT_LIST_HEAD(&fbo->lru);
+ INIT_LIST_HEAD(&fbo->swap);
+ INIT_LIST_HEAD(&fbo->io_reserve_lru);
+ fbo->vm_node = NULL;
+ atomic_set(&fbo->cpu_writers, 0);
+
+ fbo->sync_obj = driver->sync_obj_ref(bo->sync_obj);
+ refcount_init(&fbo->list_kref, 1);
+ refcount_init(&fbo->kref, 1);
+ fbo->destroy = &ttm_transfered_destroy;
+ fbo->acc_size = 0;
+
+ *new_obj = fbo;
+ return 0;
+}
+
+vm_memattr_t
+ttm_io_prot(uint32_t caching_flags)
+{
+#if defined(__i386__) || defined(__amd64__)
+ if (caching_flags & TTM_PL_FLAG_WC)
+ return (VM_MEMATTR_WRITE_COMBINING);
+ else
+ /*
+ * We do not support i386, look at the linux source
+ * for the reason of the comment.
+ */
+ return (VM_MEMATTR_UNCACHEABLE);
+#else
+#error Port me
+#endif
+}
+
+static int ttm_bo_ioremap(struct ttm_buffer_object *bo,
+ unsigned long offset,
+ unsigned long size,
+ struct ttm_bo_kmap_obj *map)
+{
+ struct ttm_mem_reg *mem = &bo->mem;
+
+ if (bo->mem.bus.addr) {
+ map->bo_kmap_type = ttm_bo_map_premapped;
+ map->virtual = (void *)(((u8 *)bo->mem.bus.addr) + offset);
+ } else {
+ map->bo_kmap_type = ttm_bo_map_iomap;
+ map->virtual = pmap_mapdev_attr(bo->mem.bus.base +
+ bo->mem.bus.offset + offset, size,
+ (mem->placement & TTM_PL_FLAG_WC) ?
+ VM_MEMATTR_WRITE_COMBINING : VM_MEMATTR_UNCACHEABLE);
+ map->size = size;
+ }
+ return (!map->virtual) ? -ENOMEM : 0;
+}
+
+static int ttm_bo_kmap_ttm(struct ttm_buffer_object *bo,
+ unsigned long start_page,
+ unsigned long num_pages,
+ struct ttm_bo_kmap_obj *map)
+{
+ struct ttm_mem_reg *mem = &bo->mem;
+ vm_memattr_t prot;
+ struct ttm_tt *ttm = bo->ttm;
+ int i, ret;
+
+ MPASS(ttm != NULL);
+
+ if (ttm->state == tt_unpopulated) {
+ ret = ttm->bdev->driver->ttm_tt_populate(ttm);
+ if (ret)
+ return ret;
+ }
+
+ if (num_pages == 1 && (mem->placement & TTM_PL_FLAG_CACHED)) {
+ /*
+ * We're mapping a single page, and the desired
+ * page protection is consistent with the bo.
+ */
+
+ map->bo_kmap_type = ttm_bo_map_kmap;
+ map->page = ttm->pages[start_page];
+ map->sf = sf_buf_alloc(map->page, 0);
+ map->virtual = (void *)sf_buf_kva(map->sf);
+ } else {
+ /*
+ * We need to use vmap to get the desired page protection
+ * or to make the buffer object look contiguous.
+ */
+ prot = (mem->placement & TTM_PL_FLAG_CACHED) ?
+ VM_MEMATTR_WRITE_COMBINING :
+ ttm_io_prot(mem->placement);
+ map->bo_kmap_type = ttm_bo_map_vmap;
+ map->num_pages = num_pages;
+ map->virtual = (void *)kmem_alloc_nofault(kernel_map,
+ num_pages * PAGE_SIZE);
+ if (map->virtual != NULL) {
+ for (i = 0; i < num_pages; i++) {
+ /* XXXKIB hack */
+ pmap_page_set_memattr(ttm->pages[start_page +
+ i], prot);
+ }
+ pmap_qenter((vm_offset_t)map->virtual,
+ &ttm->pages[start_page], num_pages);
+ }
+ }
+ return (!map->virtual) ? -ENOMEM : 0;
+}
+
+int ttm_bo_kmap(struct ttm_buffer_object *bo,
+ unsigned long start_page, unsigned long num_pages,
+ struct ttm_bo_kmap_obj *map)
+{
+ struct ttm_mem_type_manager *man =
+ &bo->bdev->man[bo->mem.mem_type];
+ unsigned long offset, size;
+ int ret;
+
+ MPASS(list_empty(&bo->swap));
+ map->virtual = NULL;
+ map->bo = bo;
+ if (num_pages > bo->num_pages)
+ return -EINVAL;
+ if (start_page > bo->num_pages)
+ return -EINVAL;
+#if 0
+ if (num_pages > 1 && !DRM_SUSER(DRM_CURPROC))
+ return -EPERM;
+#endif
+ (void) ttm_mem_io_lock(man, false);
+ ret = ttm_mem_io_reserve(bo->bdev, &bo->mem);
+ ttm_mem_io_unlock(man);
+ if (ret)
+ return ret;
+ if (!bo->mem.bus.is_iomem) {
+ return ttm_bo_kmap_ttm(bo, start_page, num_pages, map);
+ } else {
+ offset = start_page << PAGE_SHIFT;
+ size = num_pages << PAGE_SHIFT;
+ return ttm_bo_ioremap(bo, offset, size, map);
+ }
+}
+
+void ttm_bo_kunmap(struct ttm_bo_kmap_obj *map)
+{
+ struct ttm_buffer_object *bo = map->bo;
+ struct ttm_mem_type_manager *man =
+ &bo->bdev->man[bo->mem.mem_type];
+
+ if (!map->virtual)
+ return;
+ switch (map->bo_kmap_type) {
+ case ttm_bo_map_iomap:
+ pmap_unmapdev((vm_offset_t)map->virtual, map->size);
+ break;
+ case ttm_bo_map_vmap:
+ pmap_qremove((vm_offset_t)(map->virtual), map->num_pages);
+ kmem_free(kernel_map, (vm_offset_t)map->virtual,
+ map->num_pages * PAGE_SIZE);
+ break;
+ case ttm_bo_map_kmap:
+ sf_buf_free(map->sf);
+ break;
+ case ttm_bo_map_premapped:
+ break;
+ default:
+ MPASS(0);
+ }
+ (void) ttm_mem_io_lock(man, false);
+ ttm_mem_io_free(map->bo->bdev, &map->bo->mem);
+ ttm_mem_io_unlock(man);
+ map->virtual = NULL;
+ map->page = NULL;
+ map->sf = NULL;
+}
+
+int ttm_bo_move_accel_cleanup(struct ttm_buffer_object *bo,
+ void *sync_obj,
+ bool evict,
+ bool no_wait_gpu,
+ struct ttm_mem_reg *new_mem)
+{
+ struct ttm_bo_device *bdev = bo->bdev;
+ struct ttm_bo_driver *driver = bdev->driver;
+ struct ttm_mem_type_manager *man = &bdev->man[new_mem->mem_type];
+ struct ttm_mem_reg *old_mem = &bo->mem;
+ int ret;
+ struct ttm_buffer_object *ghost_obj;
+ void *tmp_obj = NULL;
+
+ mtx_lock(&bdev->fence_lock);
+ if (bo->sync_obj) {
+ tmp_obj = bo->sync_obj;
+ bo->sync_obj = NULL;
+ }
+ bo->sync_obj = driver->sync_obj_ref(sync_obj);
+ if (evict) {
+ ret = ttm_bo_wait(bo, false, false, false);
+ mtx_unlock(&bdev->fence_lock);
+ if (tmp_obj)
+ driver->sync_obj_unref(&tmp_obj);
+ if (ret)
+ return ret;
+
+ if ((man->flags & TTM_MEMTYPE_FLAG_FIXED) &&
+ (bo->ttm != NULL)) {
+ ttm_tt_unbind(bo->ttm);
+ ttm_tt_destroy(bo->ttm);
+ bo->ttm = NULL;
+ }
+ ttm_bo_free_old_node(bo);
+ } else {
+ /**
+ * This should help pipeline ordinary buffer moves.
+ *
+ * Hang old buffer memory on a new buffer object,
+ * and leave it to be released when the GPU
+ * operation has completed.
+ */
+
+ set_bit(TTM_BO_PRIV_FLAG_MOVING, &bo->priv_flags);
+
+ /* ttm_buffer_object_transfer accesses bo->sync_obj */
+ ret = ttm_buffer_object_transfer(bo, &ghost_obj);
+ mtx_unlock(&bdev->fence_lock);
+ if (tmp_obj)
+ driver->sync_obj_unref(&tmp_obj);
+
+ if (ret)
+ return ret;
+
+ /**
+ * If we're not moving to fixed memory, the TTM object
+ * needs to stay alive. Otherwhise hang it on the ghost
+ * bo to be unbound and destroyed.
+ */
+
+ if (!(man->flags & TTM_MEMTYPE_FLAG_FIXED))
+ ghost_obj->ttm = NULL;
+ else
+ bo->ttm = NULL;
+
+ ttm_bo_unreserve(ghost_obj);
+ ttm_bo_unref(&ghost_obj);
+ }
+
+ *old_mem = *new_mem;
+ new_mem->mm_node = NULL;
+
+ return 0;
+}
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