panthor_gem.c

  1// SPDX-License-Identifier: GPL-2.0 or MIT
  2/* Copyright 2019 Linaro, Ltd, Rob Herring <robh@kernel.org> */
  3/* Copyright 2023 Collabora ltd. */
  4
  5#include <linux/cleanup.h>
  6#include <linux/dma-buf.h>
  7#include <linux/dma-mapping.h>
  8#include <linux/err.h>
  9#include <linux/slab.h>
 10
 11#include <drm/drm_print.h>
 12#include <drm/panthor_drm.h>
 13
 14#include "panthor_device.h"
 15#include "panthor_fw.h"
 16#include "panthor_gem.h"
 17#include "panthor_mmu.h"
 18
 19#ifdef CONFIG_DEBUG_FS
 20static void panthor_gem_debugfs_bo_init(struct panthor_gem_object *bo)
 21{
 22	INIT_LIST_HEAD(&bo->debugfs.node);
 23}
 24
 25static void panthor_gem_debugfs_bo_add(struct panthor_gem_object *bo)
 26{
 27	struct panthor_device *ptdev = container_of(bo->base.base.dev,
 28						    struct panthor_device, base);
 29
 30	bo->debugfs.creator.tgid = current->group_leader->pid;
 31	get_task_comm(bo->debugfs.creator.process_name, current->group_leader);
 32
 33	mutex_lock(&ptdev->gems.lock);
 34	list_add_tail(&bo->debugfs.node, &ptdev->gems.node);
 35	mutex_unlock(&ptdev->gems.lock);
 36}
 37
 38static void panthor_gem_debugfs_bo_rm(struct panthor_gem_object *bo)
 39{
 40	struct panthor_device *ptdev = container_of(bo->base.base.dev,
 41						    struct panthor_device, base);
 42
 43	if (list_empty(&bo->debugfs.node))
 44		return;
 45
 46	mutex_lock(&ptdev->gems.lock);
 47	list_del_init(&bo->debugfs.node);
 48	mutex_unlock(&ptdev->gems.lock);
 49}
 50
 51static void panthor_gem_debugfs_set_usage_flags(struct panthor_gem_object *bo, u32 usage_flags)
 52{
 53	bo->debugfs.flags = usage_flags;
 54	panthor_gem_debugfs_bo_add(bo);
 55}
 56#else
 57static void panthor_gem_debugfs_bo_rm(struct panthor_gem_object *bo) {}
 58static void panthor_gem_debugfs_set_usage_flags(struct panthor_gem_object *bo, u32 usage_flags) {}
 59static void panthor_gem_debugfs_bo_init(struct panthor_gem_object *bo) {}
 60#endif
 61
 62static void panthor_gem_free_object(struct drm_gem_object *obj)
 63{
 64	struct panthor_gem_object *bo = to_panthor_bo(obj);
 65	struct drm_gem_object *vm_root_gem = bo->exclusive_vm_root_gem;
 66
 67	panthor_gem_debugfs_bo_rm(bo);
 68
 69	/*
 70	 * Label might have been allocated with kstrdup_const(),
 71	 * we need to take that into account when freeing the memory
 72	 */
 73	kfree_const(bo->label.str);
 74
 75	mutex_destroy(&bo->label.lock);
 76
 77	drm_gem_free_mmap_offset(&bo->base.base);
 78	drm_gem_shmem_free(&bo->base);
 79	drm_gem_object_put(vm_root_gem);
 80}
 81
 82/**
 83 * panthor_kernel_bo_destroy() - Destroy a kernel buffer object
 84 * @bo: Kernel buffer object to destroy. If NULL or an ERR_PTR(), the destruction
 85 * is skipped.
 86 */
 87void panthor_kernel_bo_destroy(struct panthor_kernel_bo *bo)
 88{
 89	struct panthor_vm *vm;
 90
 91	if (IS_ERR_OR_NULL(bo))
 92		return;
 93
 94	vm = bo->vm;
 95	panthor_kernel_bo_vunmap(bo);
 96
 97	drm_WARN_ON(bo->obj->dev,
 98		    to_panthor_bo(bo->obj)->exclusive_vm_root_gem != panthor_vm_root_gem(vm));
 99	panthor_vm_unmap_range(vm, bo->va_node.start, bo->va_node.size);
100	panthor_vm_free_va(vm, &bo->va_node);
101	drm_gem_object_put(bo->obj);
102	panthor_vm_put(vm);
103	kfree(bo);
104}
105
106/**
107 * panthor_kernel_bo_create() - Create and map a GEM object to a VM
108 * @ptdev: Device.
109 * @vm: VM to map the GEM to. If NULL, the kernel object is not GPU mapped.
110 * @size: Size of the buffer object.
111 * @bo_flags: Combination of drm_panthor_bo_flags flags.
112 * @vm_map_flags: Combination of drm_panthor_vm_bind_op_flags (only those
113 * that are related to map operations).
114 * @gpu_va: GPU address assigned when mapping to the VM.
115 * If gpu_va == PANTHOR_VM_KERNEL_AUTO_VA, the virtual address will be
116 * automatically allocated.
117 * @name: Descriptive label of the BO's contents
118 *
119 * Return: A valid pointer in case of success, an ERR_PTR() otherwise.
120 */
121struct panthor_kernel_bo *
122panthor_kernel_bo_create(struct panthor_device *ptdev, struct panthor_vm *vm,
123			 size_t size, u32 bo_flags, u32 vm_map_flags,
124			 u64 gpu_va, const char *name)
125{
126	struct drm_gem_shmem_object *obj;
127	struct panthor_kernel_bo *kbo;
128	struct panthor_gem_object *bo;
129	u32 debug_flags = PANTHOR_DEBUGFS_GEM_USAGE_FLAG_KERNEL;
130	int ret;
131
132	if (drm_WARN_ON(&ptdev->base, !vm))
133		return ERR_PTR(-EINVAL);
134
135	kbo = kzalloc(sizeof(*kbo), GFP_KERNEL);
136	if (!kbo)
137		return ERR_PTR(-ENOMEM);
138
139	obj = drm_gem_shmem_create(&ptdev->base, size);
140	if (IS_ERR(obj)) {
141		ret = PTR_ERR(obj);
142		goto err_free_bo;
143	}
144
145	bo = to_panthor_bo(&obj->base);
146	kbo->obj = &obj->base;
147	bo->flags = bo_flags;
148	bo->exclusive_vm_root_gem = panthor_vm_root_gem(vm);
149	drm_gem_object_get(bo->exclusive_vm_root_gem);
150	bo->base.base.resv = bo->exclusive_vm_root_gem->resv;
151
152	if (vm == panthor_fw_vm(ptdev))
153		debug_flags |= PANTHOR_DEBUGFS_GEM_USAGE_FLAG_FW_MAPPED;
154
155	panthor_gem_kernel_bo_set_label(kbo, name);
156	panthor_gem_debugfs_set_usage_flags(to_panthor_bo(kbo->obj), debug_flags);
157
158	/* The system and GPU MMU page size might differ, which becomes a
159	 * problem for FW sections that need to be mapped at explicit address
160	 * since our PAGE_SIZE alignment might cover a VA range that's
161	 * expected to be used for another section.
162	 * Make sure we never map more than we need.
163	 */
164	size = ALIGN(size, panthor_vm_page_size(vm));
165	ret = panthor_vm_alloc_va(vm, gpu_va, size, &kbo->va_node);
166	if (ret)
167		goto err_put_obj;
168
169	ret = panthor_vm_map_bo_range(vm, bo, 0, size, kbo->va_node.start, vm_map_flags);
170	if (ret)
171		goto err_free_va;
172
173	kbo->vm = panthor_vm_get(vm);
174	return kbo;
175
176err_free_va:
177	panthor_vm_free_va(vm, &kbo->va_node);
178
179err_put_obj:
180	drm_gem_object_put(&obj->base);
181
182err_free_bo:
183	kfree(kbo);
184	return ERR_PTR(ret);
185}
186
187static struct dma_buf *
188panthor_gem_prime_export(struct drm_gem_object *obj, int flags)
189{
190	/* We can't export GEMs that have an exclusive VM. */
191	if (to_panthor_bo(obj)->exclusive_vm_root_gem)
192		return ERR_PTR(-EINVAL);
193
194	return drm_gem_prime_export(obj, flags);
195}
196
197static enum drm_gem_object_status panthor_gem_status(struct drm_gem_object *obj)
198{
199	struct panthor_gem_object *bo = to_panthor_bo(obj);
200	enum drm_gem_object_status res = 0;
201
202	if (drm_gem_is_imported(&bo->base.base) || bo->base.pages)
203		res |= DRM_GEM_OBJECT_RESIDENT;
204
205	return res;
206}
207
208static const struct drm_gem_object_funcs panthor_gem_funcs = {
209	.free = panthor_gem_free_object,
210	.print_info = drm_gem_shmem_object_print_info,
211	.pin = drm_gem_shmem_object_pin,
212	.unpin = drm_gem_shmem_object_unpin,
213	.get_sg_table = drm_gem_shmem_object_get_sg_table,
214	.vmap = drm_gem_shmem_object_vmap,
215	.vunmap = drm_gem_shmem_object_vunmap,
216	.mmap = drm_gem_shmem_object_mmap,
217	.status = panthor_gem_status,
218	.export = panthor_gem_prime_export,
219	.vm_ops = &drm_gem_shmem_vm_ops,
220};
221
222/**
223 * panthor_gem_create_object - Implementation of driver->gem_create_object.
224 * @ddev: DRM device
225 * @size: Size in bytes of the memory the object will reference
226 *
227 * This lets the GEM helpers allocate object structs for us, and keep
228 * our BO stats correct.
229 */
230struct drm_gem_object *panthor_gem_create_object(struct drm_device *ddev, size_t size)
231{
232	struct panthor_device *ptdev = container_of(ddev, struct panthor_device, base);
233	struct panthor_gem_object *obj;
234
235	obj = kzalloc(sizeof(*obj), GFP_KERNEL);
236	if (!obj)
237		return ERR_PTR(-ENOMEM);
238
239	obj->base.base.funcs = &panthor_gem_funcs;
240	obj->base.map_wc = !ptdev->coherent;
241	mutex_init(&obj->label.lock);
242
243	panthor_gem_debugfs_bo_init(obj);
244
245	return &obj->base.base;
246}
247
248/**
249 * panthor_gem_create_with_handle() - Create a GEM object and attach it to a handle.
250 * @file: DRM file.
251 * @ddev: DRM device.
252 * @exclusive_vm: Exclusive VM. Not NULL if the GEM object can't be shared.
253 * @size: Size of the GEM object to allocate.
254 * @flags: Combination of drm_panthor_bo_flags flags.
255 * @handle: Pointer holding the handle pointing to the new GEM object.
256 *
257 * Return: Zero on success
258 */
259int
260panthor_gem_create_with_handle(struct drm_file *file,
261			       struct drm_device *ddev,
262			       struct panthor_vm *exclusive_vm,
263			       u64 *size, u32 flags, u32 *handle)
264{
265	int ret;
266	struct drm_gem_shmem_object *shmem;
267	struct panthor_gem_object *bo;
268
269	shmem = drm_gem_shmem_create(ddev, *size);
270	if (IS_ERR(shmem))
271		return PTR_ERR(shmem);
272
273	bo = to_panthor_bo(&shmem->base);
274	bo->flags = flags;
275
276	if (exclusive_vm) {
277		bo->exclusive_vm_root_gem = panthor_vm_root_gem(exclusive_vm);
278		drm_gem_object_get(bo->exclusive_vm_root_gem);
279		bo->base.base.resv = bo->exclusive_vm_root_gem->resv;
280	}
281
282	panthor_gem_debugfs_set_usage_flags(bo, 0);
283
284	/* If this is a write-combine mapping, we query the sgt to force a CPU
285	 * cache flush (dma_map_sgtable() is called when the sgt is created).
286	 * This ensures the zero-ing is visible to any uncached mapping created
287	 * by vmap/mmap.
288	 * FIXME: Ideally this should be done when pages are allocated, not at
289	 * BO creation time.
290	 */
291	if (shmem->map_wc) {
292		struct sg_table *sgt;
293
294		sgt = drm_gem_shmem_get_pages_sgt(shmem);
295		if (IS_ERR(sgt)) {
296			ret = PTR_ERR(sgt);
297			goto out_put_gem;
298		}
299	}
300
301	/*
302	 * Allocate an id of idr table where the obj is registered
303	 * and handle has the id what user can see.
304	 */
305	ret = drm_gem_handle_create(file, &shmem->base, handle);
306	if (!ret)
307		*size = bo->base.base.size;
308
309out_put_gem:
310	/* drop reference from allocate - handle holds it now. */
311	drm_gem_object_put(&shmem->base);
312
313	return ret;
314}
315
316void
317panthor_gem_bo_set_label(struct drm_gem_object *obj, const char *label)
318{
319	struct panthor_gem_object *bo = to_panthor_bo(obj);
320	const char *old_label;
321
322	scoped_guard(mutex, &bo->label.lock) {
323		old_label = bo->label.str;
324		bo->label.str = label;
325	}
326
327	kfree_const(old_label);
328}
329
330void
331panthor_gem_kernel_bo_set_label(struct panthor_kernel_bo *bo, const char *label)
332{
333	const char *str;
334
335	/* We should never attempt labelling a UM-exposed GEM object */
336	if (drm_WARN_ON(bo->obj->dev, bo->obj->handle_count > 0))
337		return;
338
339	if (!label)
340		return;
341
342	str = kstrdup_const(label, GFP_KERNEL);
343	if (!str) {
344		/* Failing to allocate memory for a label isn't a fatal condition */
345		drm_warn(bo->obj->dev, "Not enough memory to allocate BO label");
346		return;
347	}
348
349	panthor_gem_bo_set_label(bo->obj, str);
350}
351
352#ifdef CONFIG_DEBUG_FS
353struct gem_size_totals {
354	size_t size;
355	size_t resident;
356	size_t reclaimable;
357};
358
359static void panthor_gem_debugfs_print_flag_names(struct seq_file *m)
360{
361	int len;
362	int i;
363
364	static const char * const gem_state_flags_names[] = {
365		[PANTHOR_DEBUGFS_GEM_STATE_IMPORTED_BIT] = "imported",
366		[PANTHOR_DEBUGFS_GEM_STATE_EXPORTED_BIT] = "exported",
367	};
368
369	static const char * const gem_usage_flags_names[] = {
370		[PANTHOR_DEBUGFS_GEM_USAGE_KERNEL_BIT] = "kernel",
371		[PANTHOR_DEBUGFS_GEM_USAGE_FW_MAPPED_BIT] = "fw-mapped",
372	};
373
374	seq_puts(m, "GEM state flags: ");
375	for (i = 0, len = ARRAY_SIZE(gem_state_flags_names); i < len; i++) {
376		if (!gem_state_flags_names[i])
377			continue;
378		seq_printf(m, "%s (0x%x)%s", gem_state_flags_names[i],
379			   (u32)BIT(i), (i < len - 1) ? ", " : "\n");
380	}
381
382	seq_puts(m, "GEM usage flags: ");
383	for (i = 0, len = ARRAY_SIZE(gem_usage_flags_names); i < len; i++) {
384		if (!gem_usage_flags_names[i])
385			continue;
386		seq_printf(m, "%s (0x%x)%s", gem_usage_flags_names[i],
387			   (u32)BIT(i), (i < len - 1) ? ", " : "\n\n");
388	}
389}
390
391static void panthor_gem_debugfs_bo_print(struct panthor_gem_object *bo,
392					 struct seq_file *m,
393					 struct gem_size_totals *totals)
394{
395	unsigned int refcount = kref_read(&bo->base.base.refcount);
396	char creator_info[32] = {};
397	size_t resident_size;
398	u32 gem_usage_flags = bo->debugfs.flags;
399	u32 gem_state_flags = 0;
400
401	/* Skip BOs being destroyed. */
402	if (!refcount)
403		return;
404
405	resident_size = bo->base.pages ? bo->base.base.size : 0;
406
407	snprintf(creator_info, sizeof(creator_info),
408		 "%s/%d", bo->debugfs.creator.process_name, bo->debugfs.creator.tgid);
409	seq_printf(m, "%-32s%-16d%-16d%-16zd%-16zd0x%-16lx",
410		   creator_info,
411		   bo->base.base.name,
412		   refcount,
413		   bo->base.base.size,
414		   resident_size,
415		   drm_vma_node_start(&bo->base.base.vma_node));
416
417	if (bo->base.base.import_attach)
418		gem_state_flags |= PANTHOR_DEBUGFS_GEM_STATE_FLAG_IMPORTED;
419	if (bo->base.base.dma_buf)
420		gem_state_flags |= PANTHOR_DEBUGFS_GEM_STATE_FLAG_EXPORTED;
421
422	seq_printf(m, "0x%-8x 0x%-10x", gem_state_flags, gem_usage_flags);
423
424	scoped_guard(mutex, &bo->label.lock) {
425		seq_printf(m, "%s\n", bo->label.str ? : "");
426	}
427
428	totals->size += bo->base.base.size;
429	totals->resident += resident_size;
430	if (bo->base.madv > 0)
431		totals->reclaimable += resident_size;
432}
433
434void panthor_gem_debugfs_print_bos(struct panthor_device *ptdev,
435				   struct seq_file *m)
436{
437	struct gem_size_totals totals = {0};
438	struct panthor_gem_object *bo;
439
440	panthor_gem_debugfs_print_flag_names(m);
441
442	seq_puts(m, "created-by                      global-name     refcount        size            resident-size   file-offset       state      usage       label\n");
443	seq_puts(m, "----------------------------------------------------------------------------------------------------------------------------------------------\n");
444
445	scoped_guard(mutex, &ptdev->gems.lock) {
446		list_for_each_entry(bo, &ptdev->gems.node, debugfs.node) {
447			panthor_gem_debugfs_bo_print(bo, m, &totals);
448		}
449	}
450
451	seq_puts(m, "==============================================================================================================================================\n");
452	seq_printf(m, "Total size: %zd, Total resident: %zd, Total reclaimable: %zd\n",
453		   totals.size, totals.resident, totals.reclaimable);
454}
455#endif