1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * TI Keystone DSP remoteproc driver
4 *
5 * Copyright (C) 2015-2017 Texas Instruments Incorporated - http://www.ti.com/
6 */
7
8 #include <linux/module.h>
9 #include <linux/slab.h>
10 #include <linux/io.h>
11 #include <linux/interrupt.h>
12 #include <linux/platform_device.h>
13 #include <linux/pm_runtime.h>
14 #include <linux/workqueue.h>
15 #include <linux/of_address.h>
16 #include <linux/of_reserved_mem.h>
17 #include <linux/gpio/consumer.h>
18 #include <linux/regmap.h>
19 #include <linux/mfd/syscon.h>
20 #include <linux/remoteproc.h>
21 #include <linux/reset.h>
22
23 #include "remoteproc_internal.h"
24
25 #define KEYSTONE_RPROC_LOCAL_ADDRESS_MASK (SZ_16M - 1)
26
27 /**
28 * struct keystone_rproc_mem - internal memory structure
29 * @cpu_addr: MPU virtual address of the memory region
30 * @bus_addr: Bus address used to access the memory region
31 * @dev_addr: Device address of the memory region from DSP view
32 * @size: Size of the memory region
33 */
34 struct keystone_rproc_mem {
35 void __iomem *cpu_addr;
36 phys_addr_t bus_addr;
37 u32 dev_addr;
38 size_t size;
39 };
40
41 /**
42 * struct keystone_rproc - keystone remote processor driver structure
43 * @dev: cached device pointer
44 * @rproc: remoteproc device handle
45 * @mem: internal memory regions data
46 * @num_mems: number of internal memory regions
47 * @dev_ctrl: device control regmap handle
48 * @reset: reset control handle
49 * @boot_offset: boot register offset in @dev_ctrl regmap
50 * @irq_ring: irq entry for vring
51 * @irq_fault: irq entry for exception
52 * @kick_gpio: gpio used for virtio kicks
53 * @workqueue: workqueue for processing virtio interrupts
54 */
55 struct keystone_rproc {
56 struct device *dev;
57 struct rproc *rproc;
58 struct keystone_rproc_mem *mem;
59 int num_mems;
60 struct regmap *dev_ctrl;
61 struct reset_control *reset;
62 struct gpio_desc *kick_gpio;
63 u32 boot_offset;
64 int irq_ring;
65 int irq_fault;
66 struct work_struct workqueue;
67 };
68
69 /* Put the DSP processor into reset */
keystone_rproc_dsp_reset(struct keystone_rproc * ksproc)70 static void keystone_rproc_dsp_reset(struct keystone_rproc *ksproc)
71 {
72 reset_control_assert(ksproc->reset);
73 }
74
75 /* Configure the boot address and boot the DSP processor */
keystone_rproc_dsp_boot(struct keystone_rproc * ksproc,u32 boot_addr)76 static int keystone_rproc_dsp_boot(struct keystone_rproc *ksproc, u32 boot_addr)
77 {
78 int ret;
79
80 if (boot_addr & (SZ_1K - 1)) {
81 dev_err(ksproc->dev, "invalid boot address 0x%x, must be aligned on a 1KB boundary\n",
82 boot_addr);
83 return -EINVAL;
84 }
85
86 ret = regmap_write(ksproc->dev_ctrl, ksproc->boot_offset, boot_addr);
87 if (ret) {
88 dev_err(ksproc->dev, "regmap_write of boot address failed, status = %d\n",
89 ret);
90 return ret;
91 }
92
93 reset_control_deassert(ksproc->reset);
94
95 return 0;
96 }
97
98 /*
99 * Process the remoteproc exceptions
100 *
101 * The exception reporting on Keystone DSP remote processors is very simple
102 * compared to the equivalent processors on the OMAP family, it is notified
103 * through a software-designed specific interrupt source in the IPC interrupt
104 * generation register.
105 *
106 * This function just invokes the rproc_report_crash to report the exception
107 * to the remoteproc driver core, to trigger a recovery.
108 */
keystone_rproc_exception_interrupt(int irq,void * dev_id)109 static irqreturn_t keystone_rproc_exception_interrupt(int irq, void *dev_id)
110 {
111 struct keystone_rproc *ksproc = dev_id;
112
113 rproc_report_crash(ksproc->rproc, RPROC_FATAL_ERROR);
114
115 return IRQ_HANDLED;
116 }
117
118 /*
119 * Main virtqueue message workqueue function
120 *
121 * This function is executed upon scheduling of the keystone remoteproc
122 * driver's workqueue. The workqueue is scheduled by the vring ISR handler.
123 *
124 * There is no payload message indicating the virtqueue index as is the
125 * case with mailbox-based implementations on OMAP family. As such, this
126 * handler processes both the Tx and Rx virtqueue indices on every invocation.
127 * The rproc_vq_interrupt function can detect if there are new unprocessed
128 * messages or not (returns IRQ_NONE vs IRQ_HANDLED), but there is no need
129 * to check for these return values. The index 0 triggering will process all
130 * pending Rx buffers, and the index 1 triggering will process all newly
131 * available Tx buffers and will wakeup any potentially blocked senders.
132 *
133 * NOTE:
134 * 1. A payload could be added by using some of the source bits in the
135 * IPC interrupt generation registers, but this would need additional
136 * changes to the overall IPC stack, and currently there are no benefits
137 * of adapting that approach.
138 * 2. The current logic is based on an inherent design assumption of supporting
139 * only 2 vrings, but this can be changed if needed.
140 */
handle_event(struct work_struct * work)141 static void handle_event(struct work_struct *work)
142 {
143 struct keystone_rproc *ksproc =
144 container_of(work, struct keystone_rproc, workqueue);
145
146 rproc_vq_interrupt(ksproc->rproc, 0);
147 rproc_vq_interrupt(ksproc->rproc, 1);
148 }
149
150 /*
151 * Interrupt handler for processing vring kicks from remote processor
152 */
keystone_rproc_vring_interrupt(int irq,void * dev_id)153 static irqreturn_t keystone_rproc_vring_interrupt(int irq, void *dev_id)
154 {
155 struct keystone_rproc *ksproc = dev_id;
156
157 schedule_work(&ksproc->workqueue);
158
159 return IRQ_HANDLED;
160 }
161
162 /*
163 * Power up the DSP remote processor.
164 *
165 * This function will be invoked only after the firmware for this rproc
166 * was loaded, parsed successfully, and all of its resource requirements
167 * were met.
168 */
keystone_rproc_start(struct rproc * rproc)169 static int keystone_rproc_start(struct rproc *rproc)
170 {
171 struct keystone_rproc *ksproc = rproc->priv;
172 int ret;
173
174 INIT_WORK(&ksproc->workqueue, handle_event);
175
176 ret = request_irq(ksproc->irq_ring, keystone_rproc_vring_interrupt, 0,
177 dev_name(ksproc->dev), ksproc);
178 if (ret) {
179 dev_err(ksproc->dev, "failed to enable vring interrupt, ret = %d\n",
180 ret);
181 goto out;
182 }
183
184 ret = request_irq(ksproc->irq_fault, keystone_rproc_exception_interrupt,
185 0, dev_name(ksproc->dev), ksproc);
186 if (ret) {
187 dev_err(ksproc->dev, "failed to enable exception interrupt, ret = %d\n",
188 ret);
189 goto free_vring_irq;
190 }
191
192 ret = keystone_rproc_dsp_boot(ksproc, rproc->bootaddr);
193 if (ret)
194 goto free_exc_irq;
195
196 return 0;
197
198 free_exc_irq:
199 free_irq(ksproc->irq_fault, ksproc);
200 free_vring_irq:
201 free_irq(ksproc->irq_ring, ksproc);
202 flush_work(&ksproc->workqueue);
203 out:
204 return ret;
205 }
206
207 /*
208 * Stop the DSP remote processor.
209 *
210 * This function puts the DSP processor into reset, and finishes processing
211 * of any pending messages.
212 */
keystone_rproc_stop(struct rproc * rproc)213 static int keystone_rproc_stop(struct rproc *rproc)
214 {
215 struct keystone_rproc *ksproc = rproc->priv;
216
217 keystone_rproc_dsp_reset(ksproc);
218 free_irq(ksproc->irq_fault, ksproc);
219 free_irq(ksproc->irq_ring, ksproc);
220 flush_work(&ksproc->workqueue);
221
222 return 0;
223 }
224
225 /*
226 * Kick the remote processor to notify about pending unprocessed messages.
227 * The vqid usage is not used and is inconsequential, as the kick is performed
228 * through a simulated GPIO (a bit in an IPC interrupt-triggering register),
229 * the remote processor is expected to process both its Tx and Rx virtqueues.
230 */
keystone_rproc_kick(struct rproc * rproc,int vqid)231 static void keystone_rproc_kick(struct rproc *rproc, int vqid)
232 {
233 struct keystone_rproc *ksproc = rproc->priv;
234
235 if (!ksproc->kick_gpio)
236 return;
237
238 gpiod_set_value(ksproc->kick_gpio, 1);
239 }
240
241 /*
242 * Custom function to translate a DSP device address (internal RAMs only) to a
243 * kernel virtual address. The DSPs can access their RAMs at either an internal
244 * address visible only from a DSP, or at the SoC-level bus address. Both these
245 * addresses need to be looked through for translation. The translated addresses
246 * can be used either by the remoteproc core for loading (when using kernel
247 * remoteproc loader), or by any rpmsg bus drivers.
248 */
keystone_rproc_da_to_va(struct rproc * rproc,u64 da,size_t len,bool * is_iomem)249 static void *keystone_rproc_da_to_va(struct rproc *rproc, u64 da, size_t len, bool *is_iomem)
250 {
251 struct keystone_rproc *ksproc = rproc->priv;
252 void __iomem *va = NULL;
253 phys_addr_t bus_addr;
254 u32 dev_addr, offset;
255 size_t size;
256 int i;
257
258 if (len == 0)
259 return NULL;
260
261 for (i = 0; i < ksproc->num_mems; i++) {
262 bus_addr = ksproc->mem[i].bus_addr;
263 dev_addr = ksproc->mem[i].dev_addr;
264 size = ksproc->mem[i].size;
265
266 if (da < KEYSTONE_RPROC_LOCAL_ADDRESS_MASK) {
267 /* handle DSP-view addresses */
268 if ((da >= dev_addr) &&
269 ((da + len) <= (dev_addr + size))) {
270 offset = da - dev_addr;
271 va = ksproc->mem[i].cpu_addr + offset;
272 break;
273 }
274 } else {
275 /* handle SoC-view addresses */
276 if ((da >= bus_addr) &&
277 (da + len) <= (bus_addr + size)) {
278 offset = da - bus_addr;
279 va = ksproc->mem[i].cpu_addr + offset;
280 break;
281 }
282 }
283 }
284
285 return (__force void *)va;
286 }
287
288 static const struct rproc_ops keystone_rproc_ops = {
289 .start = keystone_rproc_start,
290 .stop = keystone_rproc_stop,
291 .kick = keystone_rproc_kick,
292 .da_to_va = keystone_rproc_da_to_va,
293 };
294
keystone_rproc_of_get_memories(struct platform_device * pdev,struct keystone_rproc * ksproc)295 static int keystone_rproc_of_get_memories(struct platform_device *pdev,
296 struct keystone_rproc *ksproc)
297 {
298 static const char * const mem_names[] = {"l2sram", "l1pram", "l1dram"};
299 struct device *dev = &pdev->dev;
300 struct resource *res;
301 int num_mems = 0;
302 int i;
303
304 num_mems = ARRAY_SIZE(mem_names);
305 ksproc->mem = devm_kcalloc(ksproc->dev, num_mems,
306 sizeof(*ksproc->mem), GFP_KERNEL);
307 if (!ksproc->mem)
308 return -ENOMEM;
309
310 for (i = 0; i < num_mems; i++) {
311 res = platform_get_resource_byname(pdev, IORESOURCE_MEM,
312 mem_names[i]);
313 ksproc->mem[i].cpu_addr = devm_ioremap_resource(dev, res);
314 if (IS_ERR(ksproc->mem[i].cpu_addr)) {
315 dev_err(dev, "failed to parse and map %s memory\n",
316 mem_names[i]);
317 return PTR_ERR(ksproc->mem[i].cpu_addr);
318 }
319 ksproc->mem[i].bus_addr = res->start;
320 ksproc->mem[i].dev_addr =
321 res->start & KEYSTONE_RPROC_LOCAL_ADDRESS_MASK;
322 ksproc->mem[i].size = resource_size(res);
323
324 /* zero out memories to start in a pristine state */
325 memset((__force void *)ksproc->mem[i].cpu_addr, 0,
326 ksproc->mem[i].size);
327 }
328 ksproc->num_mems = num_mems;
329
330 return 0;
331 }
332
keystone_rproc_of_get_dev_syscon(struct platform_device * pdev,struct keystone_rproc * ksproc)333 static int keystone_rproc_of_get_dev_syscon(struct platform_device *pdev,
334 struct keystone_rproc *ksproc)
335 {
336 struct device_node *np = pdev->dev.of_node;
337 struct device *dev = &pdev->dev;
338 int ret;
339
340 if (!of_property_read_bool(np, "ti,syscon-dev")) {
341 dev_err(dev, "ti,syscon-dev property is absent\n");
342 return -EINVAL;
343 }
344
345 ksproc->dev_ctrl =
346 syscon_regmap_lookup_by_phandle(np, "ti,syscon-dev");
347 if (IS_ERR(ksproc->dev_ctrl)) {
348 ret = PTR_ERR(ksproc->dev_ctrl);
349 return ret;
350 }
351
352 if (of_property_read_u32_index(np, "ti,syscon-dev", 1,
353 &ksproc->boot_offset)) {
354 dev_err(dev, "couldn't read the boot register offset\n");
355 return -EINVAL;
356 }
357
358 return 0;
359 }
360
keystone_rproc_probe(struct platform_device * pdev)361 static int keystone_rproc_probe(struct platform_device *pdev)
362 {
363 struct device *dev = &pdev->dev;
364 struct device_node *np = dev->of_node;
365 struct keystone_rproc *ksproc;
366 struct rproc *rproc;
367 int dsp_id;
368 char *fw_name = NULL;
369 char *template = "keystone-dsp%d-fw";
370 int name_len = 0;
371 int ret = 0;
372
373 if (!np) {
374 dev_err(dev, "only DT-based devices are supported\n");
375 return -ENODEV;
376 }
377
378 dsp_id = of_alias_get_id(np, "rproc");
379 if (dsp_id < 0) {
380 dev_warn(dev, "device does not have an alias id\n");
381 return dsp_id;
382 }
383
384 /* construct a custom default fw name - subject to change in future */
385 name_len = strlen(template); /* assuming a single digit alias */
386 fw_name = devm_kzalloc(dev, name_len, GFP_KERNEL);
387 if (!fw_name)
388 return -ENOMEM;
389 snprintf(fw_name, name_len, template, dsp_id);
390
391 rproc = rproc_alloc(dev, dev_name(dev), &keystone_rproc_ops, fw_name,
392 sizeof(*ksproc));
393 if (!rproc)
394 return -ENOMEM;
395
396 rproc->has_iommu = false;
397 ksproc = rproc->priv;
398 ksproc->rproc = rproc;
399 ksproc->dev = dev;
400
401 ret = keystone_rproc_of_get_dev_syscon(pdev, ksproc);
402 if (ret)
403 goto free_rproc;
404
405 ksproc->reset = devm_reset_control_get_exclusive(dev, NULL);
406 if (IS_ERR(ksproc->reset)) {
407 ret = PTR_ERR(ksproc->reset);
408 goto free_rproc;
409 }
410
411 /* enable clock for accessing DSP internal memories */
412 pm_runtime_enable(dev);
413 ret = pm_runtime_resume_and_get(dev);
414 if (ret < 0) {
415 dev_err(dev, "failed to enable clock, status = %d\n", ret);
416 goto disable_rpm;
417 }
418
419 ret = keystone_rproc_of_get_memories(pdev, ksproc);
420 if (ret)
421 goto disable_clk;
422
423 ksproc->irq_ring = platform_get_irq_byname(pdev, "vring");
424 if (ksproc->irq_ring < 0) {
425 ret = ksproc->irq_ring;
426 goto disable_clk;
427 }
428
429 ksproc->irq_fault = platform_get_irq_byname(pdev, "exception");
430 if (ksproc->irq_fault < 0) {
431 ret = ksproc->irq_fault;
432 goto disable_clk;
433 }
434
435 ksproc->kick_gpio = gpiod_get(dev, "kick", GPIOD_ASIS);
436 ret = PTR_ERR_OR_ZERO(ksproc->kick_gpio);
437 if (ret) {
438 dev_err(dev, "failed to get gpio for virtio kicks, status = %d\n",
439 ret);
440 goto disable_clk;
441 }
442
443 if (of_reserved_mem_device_init(dev))
444 dev_warn(dev, "device does not have specific CMA pool\n");
445
446 /* ensure the DSP is in reset before loading firmware */
447 ret = reset_control_status(ksproc->reset);
448 if (ret < 0) {
449 dev_err(dev, "failed to get reset status, status = %d\n", ret);
450 goto release_mem;
451 } else if (ret == 0) {
452 WARN(1, "device is not in reset\n");
453 keystone_rproc_dsp_reset(ksproc);
454 }
455
456 ret = rproc_add(rproc);
457 if (ret) {
458 dev_err(dev, "failed to add register device with remoteproc core, status = %d\n",
459 ret);
460 goto release_mem;
461 }
462
463 platform_set_drvdata(pdev, ksproc);
464
465 return 0;
466
467 release_mem:
468 of_reserved_mem_device_release(dev);
469 gpiod_put(ksproc->kick_gpio);
470 disable_clk:
471 pm_runtime_put_sync(dev);
472 disable_rpm:
473 pm_runtime_disable(dev);
474 free_rproc:
475 rproc_free(rproc);
476 return ret;
477 }
478
keystone_rproc_remove(struct platform_device * pdev)479 static void keystone_rproc_remove(struct platform_device *pdev)
480 {
481 struct keystone_rproc *ksproc = platform_get_drvdata(pdev);
482
483 rproc_del(ksproc->rproc);
484 gpiod_put(ksproc->kick_gpio);
485 pm_runtime_put_sync(&pdev->dev);
486 pm_runtime_disable(&pdev->dev);
487 rproc_free(ksproc->rproc);
488 of_reserved_mem_device_release(&pdev->dev);
489 }
490
491 static const struct of_device_id keystone_rproc_of_match[] = {
492 { .compatible = "ti,k2hk-dsp", },
493 { .compatible = "ti,k2l-dsp", },
494 { .compatible = "ti,k2e-dsp", },
495 { .compatible = "ti,k2g-dsp", },
496 { /* sentinel */ },
497 };
498 MODULE_DEVICE_TABLE(of, keystone_rproc_of_match);
499
500 static struct platform_driver keystone_rproc_driver = {
501 .probe = keystone_rproc_probe,
502 .remove_new = keystone_rproc_remove,
503 .driver = {
504 .name = "keystone-rproc",
505 .of_match_table = keystone_rproc_of_match,
506 },
507 };
508
509 module_platform_driver(keystone_rproc_driver);
510
511 MODULE_AUTHOR("Suman Anna <s-anna@ti.com>");
512 MODULE_LICENSE("GPL v2");
513 MODULE_DESCRIPTION("TI Keystone DSP Remoteproc driver");
514