1 /* 2 * Copyright (c) 2016-2017, Linaro Ltd 3 * 4 * This program is free software; you can redistribute it and/or modify 5 * it under the terms of the GNU General Public License version 2 and 6 * only version 2 as published by the Free Software Foundation. 7 * 8 * This program is distributed in the hope that it will be useful, 9 * but WITHOUT ANY WARRANTY; without even the implied warranty of 10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 11 * GNU General Public License for more details. 12 */ 13 14 #include <linux/idr.h> 15 #include <linux/interrupt.h> 16 #include <linux/io.h> 17 #include <linux/list.h> 18 #include <linux/mfd/syscon.h> 19 #include <linux/module.h> 20 #include <linux/of.h> 21 #include <linux/of_address.h> 22 #include <linux/platform_device.h> 23 #include <linux/regmap.h> 24 #include <linux/rpmsg.h> 25 #include <linux/slab.h> 26 #include <linux/workqueue.h> 27 #include <linux/mailbox_client.h> 28 29 #include "rpmsg_internal.h" 30 #include "qcom_glink_native.h" 31 32 #define RPM_TOC_SIZE 256 33 #define RPM_TOC_MAGIC 0x67727430 /* grt0 */ 34 #define RPM_TOC_MAX_ENTRIES ((RPM_TOC_SIZE - sizeof(struct rpm_toc)) / \ 35 sizeof(struct rpm_toc_entry)) 36 37 #define RPM_TX_FIFO_ID 0x61703272 /* ap2r */ 38 #define RPM_RX_FIFO_ID 0x72326170 /* r2ap */ 39 40 #define to_rpm_pipe(p) container_of(p, struct glink_rpm_pipe, native) 41 42 struct rpm_toc_entry { 43 __le32 id; 44 __le32 offset; 45 __le32 size; 46 } __packed; 47 48 struct rpm_toc { 49 __le32 magic; 50 __le32 count; 51 52 struct rpm_toc_entry entries[]; 53 } __packed; 54 55 struct glink_rpm_pipe { 56 struct qcom_glink_pipe native; 57 58 void __iomem *tail; 59 void __iomem *head; 60 61 void __iomem *fifo; 62 }; 63 64 static size_t glink_rpm_rx_avail(struct qcom_glink_pipe *glink_pipe) 65 { 66 struct glink_rpm_pipe *pipe = to_rpm_pipe(glink_pipe); 67 unsigned int head; 68 unsigned int tail; 69 70 head = readl(pipe->head); 71 tail = readl(pipe->tail); 72 73 if (head < tail) 74 return pipe->native.length - tail + head; 75 else 76 return head - tail; 77 } 78 79 static void glink_rpm_rx_peak(struct qcom_glink_pipe *glink_pipe, 80 void *data, unsigned int offset, size_t count) 81 { 82 struct glink_rpm_pipe *pipe = to_rpm_pipe(glink_pipe); 83 unsigned int tail; 84 size_t len; 85 86 tail = readl(pipe->tail); 87 tail += offset; 88 if (tail >= pipe->native.length) 89 tail -= pipe->native.length; 90 91 len = min_t(size_t, count, pipe->native.length - tail); 92 if (len) { 93 __ioread32_copy(data, pipe->fifo + tail, 94 len / sizeof(u32)); 95 } 96 97 if (len != count) { 98 __ioread32_copy(data + len, pipe->fifo, 99 (count - len) / sizeof(u32)); 100 } 101 } 102 103 static void glink_rpm_rx_advance(struct qcom_glink_pipe *glink_pipe, 104 size_t count) 105 { 106 struct glink_rpm_pipe *pipe = to_rpm_pipe(glink_pipe); 107 unsigned int tail; 108 109 tail = readl(pipe->tail); 110 111 tail += count; 112 if (tail >= pipe->native.length) 113 tail -= pipe->native.length; 114 115 writel(tail, pipe->tail); 116 } 117 118 static size_t glink_rpm_tx_avail(struct qcom_glink_pipe *glink_pipe) 119 { 120 struct glink_rpm_pipe *pipe = to_rpm_pipe(glink_pipe); 121 unsigned int head; 122 unsigned int tail; 123 124 head = readl(pipe->head); 125 tail = readl(pipe->tail); 126 127 if (tail <= head) 128 return pipe->native.length - head + tail; 129 else 130 return tail - head; 131 } 132 133 static unsigned int glink_rpm_tx_write_one(struct glink_rpm_pipe *pipe, 134 unsigned int head, 135 const void *data, size_t count) 136 { 137 size_t len; 138 139 len = min_t(size_t, count, pipe->native.length - head); 140 if (len) { 141 __iowrite32_copy(pipe->fifo + head, data, 142 len / sizeof(u32)); 143 } 144 145 if (len != count) { 146 __iowrite32_copy(pipe->fifo, data + len, 147 (count - len) / sizeof(u32)); 148 } 149 150 head += count; 151 if (head >= pipe->native.length) 152 head -= pipe->native.length; 153 154 return head; 155 } 156 157 static void glink_rpm_tx_write(struct qcom_glink_pipe *glink_pipe, 158 const void *hdr, size_t hlen, 159 const void *data, size_t dlen) 160 { 161 struct glink_rpm_pipe *pipe = to_rpm_pipe(glink_pipe); 162 size_t tlen = hlen + dlen; 163 size_t aligned_dlen; 164 unsigned int head; 165 char padding[8] = {0}; 166 size_t pad; 167 168 /* Header length comes from glink native and is always 4 byte aligned */ 169 if (WARN(hlen % 4, "Glink Header length must be 4 bytes aligned\n")) 170 return; 171 172 /* 173 * Move the unaligned tail of the message to the padding chunk, to 174 * ensure word aligned accesses 175 */ 176 aligned_dlen = ALIGN_DOWN(dlen, 4); 177 if (aligned_dlen != dlen) 178 memcpy(padding, data + aligned_dlen, dlen - aligned_dlen); 179 180 head = readl(pipe->head); 181 head = glink_rpm_tx_write_one(pipe, head, hdr, hlen); 182 head = glink_rpm_tx_write_one(pipe, head, data, aligned_dlen); 183 184 pad = ALIGN(tlen, 8) - ALIGN_DOWN(tlen, 4); 185 if (pad) 186 head = glink_rpm_tx_write_one(pipe, head, padding, pad); 187 writel(head, pipe->head); 188 } 189 190 static int glink_rpm_parse_toc(struct device *dev, 191 void __iomem *msg_ram, 192 size_t msg_ram_size, 193 struct glink_rpm_pipe *rx, 194 struct glink_rpm_pipe *tx) 195 { 196 struct rpm_toc *toc; 197 int num_entries; 198 unsigned int id; 199 size_t offset; 200 size_t size; 201 void *buf; 202 int i; 203 204 buf = kzalloc(RPM_TOC_SIZE, GFP_KERNEL); 205 if (!buf) 206 return -ENOMEM; 207 208 __ioread32_copy(buf, msg_ram + msg_ram_size - RPM_TOC_SIZE, 209 RPM_TOC_SIZE / sizeof(u32)); 210 211 toc = buf; 212 213 if (le32_to_cpu(toc->magic) != RPM_TOC_MAGIC) { 214 dev_err(dev, "RPM TOC has invalid magic\n"); 215 goto err_inval; 216 } 217 218 num_entries = le32_to_cpu(toc->count); 219 if (num_entries > RPM_TOC_MAX_ENTRIES) { 220 dev_err(dev, "Invalid number of toc entries\n"); 221 goto err_inval; 222 } 223 224 for (i = 0; i < num_entries; i++) { 225 id = le32_to_cpu(toc->entries[i].id); 226 offset = le32_to_cpu(toc->entries[i].offset); 227 size = le32_to_cpu(toc->entries[i].size); 228 229 if (offset > msg_ram_size || offset + size > msg_ram_size) { 230 dev_err(dev, "TOC entry with invalid size\n"); 231 continue; 232 } 233 234 switch (id) { 235 case RPM_RX_FIFO_ID: 236 rx->native.length = size; 237 238 rx->tail = msg_ram + offset; 239 rx->head = msg_ram + offset + sizeof(u32); 240 rx->fifo = msg_ram + offset + 2 * sizeof(u32); 241 break; 242 case RPM_TX_FIFO_ID: 243 tx->native.length = size; 244 245 tx->tail = msg_ram + offset; 246 tx->head = msg_ram + offset + sizeof(u32); 247 tx->fifo = msg_ram + offset + 2 * sizeof(u32); 248 break; 249 } 250 } 251 252 if (!rx->fifo || !tx->fifo) { 253 dev_err(dev, "Unable to find rx and tx descriptors\n"); 254 goto err_inval; 255 } 256 257 kfree(buf); 258 return 0; 259 260 err_inval: 261 kfree(buf); 262 return -EINVAL; 263 } 264 265 static int glink_rpm_probe(struct platform_device *pdev) 266 { 267 struct qcom_glink *glink; 268 struct glink_rpm_pipe *rx_pipe; 269 struct glink_rpm_pipe *tx_pipe; 270 struct device_node *np; 271 void __iomem *msg_ram; 272 size_t msg_ram_size; 273 struct device *dev = &pdev->dev; 274 struct resource r; 275 int ret; 276 277 rx_pipe = devm_kzalloc(&pdev->dev, sizeof(*rx_pipe), GFP_KERNEL); 278 tx_pipe = devm_kzalloc(&pdev->dev, sizeof(*tx_pipe), GFP_KERNEL); 279 if (!rx_pipe || !tx_pipe) 280 return -ENOMEM; 281 282 np = of_parse_phandle(dev->of_node, "qcom,rpm-msg-ram", 0); 283 ret = of_address_to_resource(np, 0, &r); 284 of_node_put(np); 285 if (ret) 286 return ret; 287 288 msg_ram = devm_ioremap(dev, r.start, resource_size(&r)); 289 msg_ram_size = resource_size(&r); 290 if (!msg_ram) 291 return -ENOMEM; 292 293 ret = glink_rpm_parse_toc(dev, msg_ram, msg_ram_size, 294 rx_pipe, tx_pipe); 295 if (ret) 296 return ret; 297 298 /* Pipe specific accessors */ 299 rx_pipe->native.avail = glink_rpm_rx_avail; 300 rx_pipe->native.peak = glink_rpm_rx_peak; 301 rx_pipe->native.advance = glink_rpm_rx_advance; 302 tx_pipe->native.avail = glink_rpm_tx_avail; 303 tx_pipe->native.write = glink_rpm_tx_write; 304 305 writel(0, tx_pipe->head); 306 writel(0, rx_pipe->tail); 307 308 glink = qcom_glink_native_probe(&pdev->dev, 309 0, 310 &rx_pipe->native, 311 &tx_pipe->native, 312 true); 313 if (IS_ERR(glink)) 314 return PTR_ERR(glink); 315 316 platform_set_drvdata(pdev, glink); 317 318 return 0; 319 } 320 321 static int glink_rpm_remove(struct platform_device *pdev) 322 { 323 struct qcom_glink *glink = platform_get_drvdata(pdev); 324 325 qcom_glink_native_remove(glink); 326 327 return 0; 328 } 329 330 static const struct of_device_id glink_rpm_of_match[] = { 331 { .compatible = "qcom,glink-rpm" }, 332 {} 333 }; 334 MODULE_DEVICE_TABLE(of, glink_rpm_of_match); 335 336 static struct platform_driver glink_rpm_driver = { 337 .probe = glink_rpm_probe, 338 .remove = glink_rpm_remove, 339 .driver = { 340 .name = "qcom_glink_rpm", 341 .of_match_table = glink_rpm_of_match, 342 }, 343 }; 344 345 static int __init glink_rpm_init(void) 346 { 347 return platform_driver_register(&glink_rpm_driver); 348 } 349 subsys_initcall(glink_rpm_init); 350 351 static void __exit glink_rpm_exit(void) 352 { 353 platform_driver_unregister(&glink_rpm_driver); 354 } 355 module_exit(glink_rpm_exit); 356 357 MODULE_AUTHOR("Bjorn Andersson <bjorn.andersson@linaro.org>"); 358 MODULE_DESCRIPTION("Qualcomm GLINK RPM driver"); 359 MODULE_LICENSE("GPL v2"); 360