xref: /openbmc/linux/drivers/net/ipa/ipa_mem.c (revision 022dacdd)
1 // SPDX-License-Identifier: GPL-2.0
2 
3 /* Copyright (c) 2012-2018, The Linux Foundation. All rights reserved.
4  * Copyright (C) 2019-2020 Linaro Ltd.
5  */
6 
7 #include <linux/types.h>
8 #include <linux/bitfield.h>
9 #include <linux/bug.h>
10 #include <linux/dma-mapping.h>
11 #include <linux/io.h>
12 
13 #include "ipa.h"
14 #include "ipa_reg.h"
15 #include "ipa_cmd.h"
16 #include "ipa_mem.h"
17 #include "ipa_data.h"
18 #include "ipa_table.h"
19 #include "gsi_trans.h"
20 
21 /* "Canary" value placed between memory regions to detect overflow */
22 #define IPA_MEM_CANARY_VAL		cpu_to_le32(0xdeadbeef)
23 
24 /* Add an immediate command to a transaction that zeroes a memory region */
25 static void
26 ipa_mem_zero_region_add(struct gsi_trans *trans, const struct ipa_mem *mem)
27 {
28 	struct ipa *ipa = container_of(trans->gsi, struct ipa, gsi);
29 	dma_addr_t addr = ipa->zero_addr;
30 
31 	if (!mem->size)
32 		return;
33 
34 	ipa_cmd_dma_shared_mem_add(trans, mem->offset, mem->size, addr, true);
35 }
36 
37 /**
38  * ipa_mem_setup() - Set up IPA AP and modem shared memory areas
39  *
40  * Set up the shared memory regions in IPA local memory.  This involves
41  * zero-filling memory regions, and in the case of header memory, telling
42  * the IPA where it's located.
43  *
44  * This function performs the initial setup of this memory.  If the modem
45  * crashes, its regions are re-zeroed in ipa_mem_zero_modem().
46  *
47  * The AP informs the modem where its portions of memory are located
48  * in a QMI exchange that occurs at modem startup.
49  *
50  * @Return:	0 if successful, or a negative error code
51  */
52 int ipa_mem_setup(struct ipa *ipa)
53 {
54 	dma_addr_t addr = ipa->zero_addr;
55 	struct gsi_trans *trans;
56 	u32 offset;
57 	u16 size;
58 
59 	/* Get a transaction to define the header memory region and to zero
60 	 * the processing context and modem memory regions.
61 	 */
62 	trans = ipa_cmd_trans_alloc(ipa, 4);
63 	if (!trans) {
64 		dev_err(&ipa->pdev->dev, "no transaction for memory setup\n");
65 		return -EBUSY;
66 	}
67 
68 	/* Initialize IPA-local header memory.  The modem and AP header
69 	 * regions are contiguous, and initialized together.
70 	 */
71 	offset = ipa->mem[IPA_MEM_MODEM_HEADER].offset;
72 	size = ipa->mem[IPA_MEM_MODEM_HEADER].size;
73 	size += ipa->mem[IPA_MEM_AP_HEADER].size;
74 
75 	ipa_cmd_hdr_init_local_add(trans, offset, size, addr);
76 
77 	ipa_mem_zero_region_add(trans, &ipa->mem[IPA_MEM_MODEM_PROC_CTX]);
78 
79 	ipa_mem_zero_region_add(trans, &ipa->mem[IPA_MEM_AP_PROC_CTX]);
80 
81 	ipa_mem_zero_region_add(trans, &ipa->mem[IPA_MEM_MODEM]);
82 
83 	gsi_trans_commit_wait(trans);
84 
85 	/* Tell the hardware where the processing context area is located */
86 	iowrite32(ipa->mem_offset + offset,
87 		  ipa->reg_virt + IPA_REG_LOCAL_PKT_PROC_CNTXT_BASE_OFFSET);
88 
89 	return 0;
90 }
91 
92 void ipa_mem_teardown(struct ipa *ipa)
93 {
94 	/* Nothing to do */
95 }
96 
97 #ifdef IPA_VALIDATE
98 
99 static bool ipa_mem_valid(struct ipa *ipa, enum ipa_mem_id mem_id)
100 {
101 	const struct ipa_mem *mem = &ipa->mem[mem_id];
102 	struct device *dev = &ipa->pdev->dev;
103 	u16 size_multiple;
104 
105 	/* Other than modem memory, sizes must be a multiple of 8 */
106 	size_multiple = mem_id == IPA_MEM_MODEM ? 4 : 8;
107 	if (mem->size % size_multiple)
108 		dev_err(dev, "region %u size not a multiple of %u bytes\n",
109 			mem_id, size_multiple);
110 	else if (mem->offset % 8)
111 		dev_err(dev, "region %u offset not 8-byte aligned\n", mem_id);
112 	else if (mem->offset < mem->canary_count * sizeof(__le32))
113 		dev_err(dev, "region %u offset too small for %hu canaries\n",
114 			mem_id, mem->canary_count);
115 	else if (mem->offset + mem->size > ipa->mem_size)
116 		dev_err(dev, "region %u ends beyond memory limit (0x%08x)\n",
117 			mem_id, ipa->mem_size);
118 	else
119 		return true;
120 
121 	return false;
122 }
123 
124 #else /* !IPA_VALIDATE */
125 
126 static bool ipa_mem_valid(struct ipa *ipa, enum ipa_mem_id mem_id)
127 {
128 	return true;
129 }
130 
131 #endif /*! IPA_VALIDATE */
132 
133 /**
134  * ipa_mem_config() - Configure IPA shared memory
135  *
136  * @Return:	0 if successful, or a negative error code
137  */
138 int ipa_mem_config(struct ipa *ipa)
139 {
140 	struct device *dev = &ipa->pdev->dev;
141 	enum ipa_mem_id mem_id;
142 	dma_addr_t addr;
143 	u32 mem_size;
144 	void *virt;
145 	u32 val;
146 
147 	/* Check the advertised location and size of the shared memory area */
148 	val = ioread32(ipa->reg_virt + IPA_REG_SHARED_MEM_SIZE_OFFSET);
149 
150 	/* The fields in the register are in 8 byte units */
151 	ipa->mem_offset = 8 * u32_get_bits(val, SHARED_MEM_BADDR_FMASK);
152 	/* Make sure the end is within the region's mapped space */
153 	mem_size = 8 * u32_get_bits(val, SHARED_MEM_SIZE_FMASK);
154 
155 	/* If the sizes don't match, issue a warning */
156 	if (ipa->mem_offset + mem_size > ipa->mem_size) {
157 		dev_warn(dev, "ignoring larger reported memory size: 0x%08x\n",
158 			mem_size);
159 	} else if (ipa->mem_offset + mem_size < ipa->mem_size) {
160 		dev_warn(dev, "limiting IPA memory size to 0x%08x\n",
161 			 mem_size);
162 		ipa->mem_size = mem_size;
163 	}
164 
165 	/* Prealloc DMA memory for zeroing regions */
166 	virt = dma_alloc_coherent(dev, IPA_MEM_MAX, &addr, GFP_KERNEL);
167 	if (!virt)
168 		return -ENOMEM;
169 	ipa->zero_addr = addr;
170 	ipa->zero_virt = virt;
171 	ipa->zero_size = IPA_MEM_MAX;
172 
173 	/* Verify each defined memory region is valid, and if indicated
174 	 * for the region, write "canary" values in the space prior to
175 	 * the region's base address.
176 	 */
177 	for (mem_id = 0; mem_id < IPA_MEM_COUNT; mem_id++) {
178 		const struct ipa_mem *mem = &ipa->mem[mem_id];
179 		u16 canary_count;
180 		__le32 *canary;
181 
182 		/* Validate all regions (even undefined ones) */
183 		if (!ipa_mem_valid(ipa, mem_id))
184 			goto err_dma_free;
185 
186 		/* Skip over undefined regions */
187 		if (!mem->offset && !mem->size)
188 			continue;
189 
190 		canary_count = mem->canary_count;
191 		if (!canary_count)
192 			continue;
193 
194 		/* Write canary values in the space before the region */
195 		canary = ipa->mem_virt + ipa->mem_offset + mem->offset;
196 		do
197 			*--canary = IPA_MEM_CANARY_VAL;
198 		while (--canary_count);
199 	}
200 
201 	/* Make sure filter and route table memory regions are valid */
202 	if (!ipa_table_valid(ipa))
203 		goto err_dma_free;
204 
205 	/* Validate memory-related properties relevant to immediate commands */
206 	if (!ipa_cmd_data_valid(ipa))
207 		goto err_dma_free;
208 
209 	/* Verify the microcontroller ring alignment (0 is OK too) */
210 	if (ipa->mem[IPA_MEM_UC_EVENT_RING].offset % 1024) {
211 		dev_err(dev, "microcontroller ring not 1024-byte aligned\n");
212 		goto err_dma_free;
213 	}
214 
215 	return 0;
216 
217 err_dma_free:
218 	dma_free_coherent(dev, IPA_MEM_MAX, ipa->zero_virt, ipa->zero_addr);
219 
220 	return -EINVAL;
221 }
222 
223 /* Inverse of ipa_mem_config() */
224 void ipa_mem_deconfig(struct ipa *ipa)
225 {
226 	struct device *dev = &ipa->pdev->dev;
227 
228 	dma_free_coherent(dev, ipa->zero_size, ipa->zero_virt, ipa->zero_addr);
229 	ipa->zero_size = 0;
230 	ipa->zero_virt = NULL;
231 	ipa->zero_addr = 0;
232 }
233 
234 /**
235  * ipa_mem_zero_modem() - Zero IPA-local memory regions owned by the modem
236  *
237  * Zero regions of IPA-local memory used by the modem.  These are configured
238  * (and initially zeroed) by ipa_mem_setup(), but if the modem crashes and
239  * restarts via SSR we need to re-initialize them.  A QMI message tells the
240  * modem where to find regions of IPA local memory it needs to know about
241  * (these included).
242  */
243 int ipa_mem_zero_modem(struct ipa *ipa)
244 {
245 	struct gsi_trans *trans;
246 
247 	/* Get a transaction to zero the modem memory, modem header,
248 	 * and modem processing context regions.
249 	 */
250 	trans = ipa_cmd_trans_alloc(ipa, 3);
251 	if (!trans) {
252 		dev_err(&ipa->pdev->dev,
253 			"no transaction to zero modem memory\n");
254 		return -EBUSY;
255 	}
256 
257 	ipa_mem_zero_region_add(trans, &ipa->mem[IPA_MEM_MODEM_HEADER]);
258 
259 	ipa_mem_zero_region_add(trans, &ipa->mem[IPA_MEM_MODEM_PROC_CTX]);
260 
261 	ipa_mem_zero_region_add(trans, &ipa->mem[IPA_MEM_MODEM]);
262 
263 	gsi_trans_commit_wait(trans);
264 
265 	return 0;
266 }
267 
268 /* Perform memory region-related initialization */
269 int ipa_mem_init(struct ipa *ipa, u32 count, const struct ipa_mem *mem)
270 {
271 	struct device *dev = &ipa->pdev->dev;
272 	struct resource *res;
273 	int ret;
274 
275 	if (count > IPA_MEM_COUNT) {
276 		dev_err(dev, "to many memory regions (%u > %u)\n",
277 			count, IPA_MEM_COUNT);
278 		return -EINVAL;
279 	}
280 
281 	ret = dma_set_mask_and_coherent(&ipa->pdev->dev, DMA_BIT_MASK(64));
282 	if (ret) {
283 		dev_err(dev, "error %d setting DMA mask\n", ret);
284 		return ret;
285 	}
286 
287 	res = platform_get_resource_byname(ipa->pdev, IORESOURCE_MEM,
288 					   "ipa-shared");
289 	if (!res) {
290 		dev_err(dev,
291 			"DT error getting \"ipa-shared\" memory property\n");
292 		return -ENODEV;
293 	}
294 
295 	ipa->mem_virt = memremap(res->start, resource_size(res), MEMREMAP_WC);
296 	if (!ipa->mem_virt) {
297 		dev_err(dev, "unable to remap \"ipa-shared\" memory\n");
298 		return -ENOMEM;
299 	}
300 
301 	ipa->mem_addr = res->start;
302 	ipa->mem_size = resource_size(res);
303 
304 	/* The ipa->mem[] array is indexed by enum ipa_mem_id values */
305 	ipa->mem = mem;
306 
307 	return 0;
308 }
309 
310 /* Inverse of ipa_mem_init() */
311 void ipa_mem_exit(struct ipa *ipa)
312 {
313 	memunmap(ipa->mem_virt);
314 }
315