1// SPDX-License-Identifier: GPL-2.0
2/* Copyright 2021 Collabora ltd. */
3
4#include <linux/err.h>
5#include <linux/device.h>
6#include <linux/devcoredump.h>
7#include <linux/moduleparam.h>
8#include <linux/iosys-map.h>
9#include <drm/panfrost_drm.h>
10#include <drm/drm_device.h>
11
12#include "panfrost_job.h"
13#include "panfrost_gem.h"
14#include "panfrost_regs.h"
15#include "panfrost_dump.h"
16#include "panfrost_device.h"
17
18static bool panfrost_dump_core = true;
19module_param_named(dump_core, panfrost_dump_core, bool, 0600);
20
21struct panfrost_dump_iterator {
22	void *start;
23	struct panfrost_dump_object_header *hdr;
24	void *data;
25};
26
27static const unsigned short panfrost_dump_registers[] = {
28	SHADER_READY_LO,
29	SHADER_READY_HI,
30	TILER_READY_LO,
31	TILER_READY_HI,
32	L2_READY_LO,
33	L2_READY_HI,
34	JOB_INT_MASK,
35	JOB_INT_STAT,
36	JS_HEAD_LO(0),
37	JS_HEAD_HI(0),
38	JS_TAIL_LO(0),
39	JS_TAIL_HI(0),
40	JS_AFFINITY_LO(0),
41	JS_AFFINITY_HI(0),
42	JS_CONFIG(0),
43	JS_STATUS(0),
44	JS_HEAD_NEXT_LO(0),
45	JS_HEAD_NEXT_HI(0),
46	JS_AFFINITY_NEXT_LO(0),
47	JS_AFFINITY_NEXT_HI(0),
48	JS_CONFIG_NEXT(0),
49	MMU_INT_MASK,
50	MMU_INT_STAT,
51	AS_TRANSTAB_LO(0),
52	AS_TRANSTAB_HI(0),
53	AS_MEMATTR_LO(0),
54	AS_MEMATTR_HI(0),
55	AS_FAULTSTATUS(0),
56	AS_FAULTADDRESS_LO(0),
57	AS_FAULTADDRESS_HI(0),
58	AS_STATUS(0),
59};
60
61static void panfrost_core_dump_header(struct panfrost_dump_iterator *iter,
62				      u32 type, void *data_end)
63{
64	struct panfrost_dump_object_header *hdr = iter->hdr;
65
66	hdr->magic = PANFROSTDUMP_MAGIC;
67	hdr->type = type;
68	hdr->file_offset = iter->data - iter->start;
69	hdr->file_size = data_end - iter->data;
70
71	iter->hdr++;
72	iter->data += hdr->file_size;
73}
74
75static void
76panfrost_core_dump_registers(struct panfrost_dump_iterator *iter,
77			     struct panfrost_device *pfdev,
78			     u32 as_nr, int slot)
79{
80	struct panfrost_dump_registers *dumpreg = iter->data;
81	unsigned int i;
82
83	for (i = 0; i < ARRAY_SIZE(panfrost_dump_registers); i++, dumpreg++) {
84		unsigned int js_as_offset = 0;
85		unsigned int reg;
86
87		if (panfrost_dump_registers[i] >= JS_BASE &&
88		    panfrost_dump_registers[i] <= JS_BASE + JS_SLOT_STRIDE)
89			js_as_offset = slot * JS_SLOT_STRIDE;
90		else if (panfrost_dump_registers[i] >= MMU_BASE &&
91			 panfrost_dump_registers[i] <= MMU_BASE + MMU_AS_STRIDE)
92			js_as_offset = (as_nr << MMU_AS_SHIFT);
93
94		reg = panfrost_dump_registers[i] + js_as_offset;
95
96		dumpreg->reg = reg;
97		dumpreg->value = gpu_read(pfdev, reg);
98	}
99
100	panfrost_core_dump_header(iter, PANFROSTDUMP_BUF_REG, dumpreg);
101}
102
103void panfrost_core_dump(struct panfrost_job *job)
104{
105	struct panfrost_device *pfdev = job->pfdev;
106	struct panfrost_dump_iterator iter;
107	struct drm_gem_object *dbo;
108	unsigned int n_obj, n_bomap_pages;
109	u64 *bomap, *bomap_start;
110	size_t file_size;
111	u32 as_nr;
112	int slot;
113	int ret, i;
114
115	as_nr = job->mmu->as;
116	slot = panfrost_job_get_slot(job);
117
118	/* Only catch the first event, or when manually re-armed */
119	if (!panfrost_dump_core)
120		return;
121	panfrost_dump_core = false;
122
123	/* At least, we dump registers and end marker */
124	n_obj = 2;
125	n_bomap_pages = 0;
126	file_size = ARRAY_SIZE(panfrost_dump_registers) *
127			sizeof(struct panfrost_dump_registers);
128
129	/* Add in the active buffer objects */
130	for (i = 0; i < job->bo_count; i++) {
131		/*
132		 * Even though the CPU could be configured to use 16K or 64K pages, this
133		 * is a very unusual situation for most kernel setups on SoCs that have
134		 * a Panfrost device. Also many places across the driver make the somewhat
135		 * arbitrary assumption that Panfrost's MMU page size is the same as the CPU's,
136		 * so let's have a sanity check to ensure that's always the case
137		 */
138		dbo = job->bos[i];
139		WARN_ON(!IS_ALIGNED(dbo->size, PAGE_SIZE));
140
141		file_size += dbo->size;
142		n_bomap_pages += dbo->size >> PAGE_SHIFT;
143		n_obj++;
144	}
145
146	/* If we have any buffer objects, add a bomap object */
147	if (n_bomap_pages) {
148		file_size += n_bomap_pages * sizeof(*bomap);
149		n_obj++;
150	}
151
152	/* Add the size of the headers */
153	file_size += sizeof(*iter.hdr) * n_obj;
154
155	/*
156	 * Allocate the file in vmalloc memory, it's likely to be big.
157	 * The reason behind these GFP flags is that we don't want to trigger the
158	 * OOM killer in the event that not enough memory could be found for our
159	 * dump file. We also don't want the allocator to do any error reporting,
160	 * as the right behaviour is failing gracefully if a big enough buffer
161	 * could not be allocated.
162	 */
163	iter.start = __vmalloc(file_size, GFP_KERNEL | __GFP_NOWARN |
164			__GFP_NORETRY);
165	if (!iter.start) {
166		dev_warn(pfdev->dev, "failed to allocate devcoredump file\n");
167		return;
168	}
169
170	/* Point the data member after the headers */
171	iter.hdr = iter.start;
172	iter.data = &iter.hdr[n_obj];
173
174	memset(iter.hdr, 0, iter.data - iter.start);
175
176	/*
177	 * For now, we write the job identifier in the register dump header,
178	 * so that we can decode the entire dump later with pandecode
179	 */
180	iter.hdr->reghdr.jc = job->jc;
181	iter.hdr->reghdr.major = PANFROSTDUMP_MAJOR;
182	iter.hdr->reghdr.minor = PANFROSTDUMP_MINOR;
183	iter.hdr->reghdr.gpu_id = pfdev->features.id;
184	iter.hdr->reghdr.nbos = job->bo_count;
185
186	panfrost_core_dump_registers(&iter, pfdev, as_nr, slot);
187
188	/* Reserve space for the bomap */
189	if (job->bo_count) {
190		bomap_start = bomap = iter.data;
191		memset(bomap, 0, sizeof(*bomap) * n_bomap_pages);
192		panfrost_core_dump_header(&iter, PANFROSTDUMP_BUF_BOMAP,
193					  bomap + n_bomap_pages);
194	}
195
196	for (i = 0; i < job->bo_count; i++) {
197		struct iosys_map map;
198		struct panfrost_gem_mapping *mapping;
199		struct panfrost_gem_object *bo;
200		struct sg_page_iter page_iter;
201		void *vaddr;
202
203		bo = to_panfrost_bo(job->bos[i]);
204		mapping = job->mappings[i];
205
206		if (!bo->base.sgt) {
207			dev_err(pfdev->dev, "Panfrost Dump: BO has no sgt, cannot dump\n");
208			iter.hdr->bomap.valid = 0;
209			goto dump_header;
210		}
211
212		ret = drm_gem_vmap_unlocked(&bo->base.base, &map);
213		if (ret) {
214			dev_err(pfdev->dev, "Panfrost Dump: couldn't map Buffer Object\n");
215			iter.hdr->bomap.valid = 0;
216			goto dump_header;
217		}
218
219		WARN_ON(!mapping->active);
220
221		iter.hdr->bomap.data[0] = bomap - bomap_start;
222
223		for_each_sgtable_page(bo->base.sgt, &page_iter, 0)
224			*bomap++ = page_to_phys(sg_page_iter_page(&page_iter));
225
226		iter.hdr->bomap.iova = mapping->mmnode.start << PAGE_SHIFT;
227
228		vaddr = map.vaddr;
229		memcpy(iter.data, vaddr, bo->base.base.size);
230
231		drm_gem_vunmap_unlocked(&bo->base.base, &map);
232
233		iter.hdr->bomap.valid = 1;
234
235dump_header:	panfrost_core_dump_header(&iter, PANFROSTDUMP_BUF_BO, iter.data +
236					  bo->base.base.size);
237	}
238	panfrost_core_dump_header(&iter, PANFROSTDUMP_BUF_TRAILER, iter.data);
239
240	dev_coredumpv(pfdev->dev, iter.start, iter.data - iter.start, GFP_KERNEL);
241}
242