1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Remote processor machine-specific module for DA8XX
4 *
5 * Copyright (C) 2013 Texas Instruments, Inc.
6 */
7
8#include <linux/bitops.h>
9#include <linux/clk.h>
10#include <linux/reset.h>
11#include <linux/err.h>
12#include <linux/interrupt.h>
13#include <linux/io.h>
14#include <linux/irq.h>
15#include <linux/kernel.h>
16#include <linux/module.h>
17#include <linux/of_reserved_mem.h>
18#include <linux/platform_device.h>
19#include <linux/remoteproc.h>
20
21#include "remoteproc_internal.h"
22
23static char *da8xx_fw_name;
24module_param(da8xx_fw_name, charp, 0444);
25MODULE_PARM_DESC(da8xx_fw_name,
26		 "Name of DSP firmware file in /lib/firmware (if not specified defaults to 'rproc-dsp-fw')");
27
28/*
29 * OMAP-L138 Technical References:
30 * http://www.ti.com/product/omap-l138
31 */
32#define SYSCFG_CHIPSIG0 BIT(0)
33#define SYSCFG_CHIPSIG1 BIT(1)
34#define SYSCFG_CHIPSIG2 BIT(2)
35#define SYSCFG_CHIPSIG3 BIT(3)
36#define SYSCFG_CHIPSIG4 BIT(4)
37
38#define DA8XX_RPROC_LOCAL_ADDRESS_MASK	(SZ_16M - 1)
39
40/**
41 * struct da8xx_rproc_mem - internal memory structure
42 * @cpu_addr: MPU virtual address of the memory region
43 * @bus_addr: Bus address used to access the memory region
44 * @dev_addr: Device address of the memory region from DSP view
45 * @size: Size of the memory region
46 */
47struct da8xx_rproc_mem {
48	void __iomem *cpu_addr;
49	phys_addr_t bus_addr;
50	u32 dev_addr;
51	size_t size;
52};
53
54/**
55 * struct da8xx_rproc - da8xx remote processor instance state
56 * @rproc: rproc handle
57 * @mem: internal memory regions data
58 * @num_mems: number of internal memory regions
59 * @dsp_clk: placeholder for platform's DSP clk
60 * @ack_fxn: chip-specific ack function for ack'ing irq
61 * @irq_data: ack_fxn function parameter
62 * @chipsig: virt ptr to DSP interrupt registers (CHIPSIG & CHIPSIG_CLR)
63 * @bootreg: virt ptr to DSP boot address register (HOST1CFG)
64 * @irq: irq # used by this instance
65 */
66struct da8xx_rproc {
67	struct rproc *rproc;
68	struct da8xx_rproc_mem *mem;
69	int num_mems;
70	struct clk *dsp_clk;
71	struct reset_control *dsp_reset;
72	void (*ack_fxn)(struct irq_data *data);
73	struct irq_data *irq_data;
74	void __iomem *chipsig;
75	void __iomem *bootreg;
76	int irq;
77};
78
79/**
80 * handle_event() - inbound virtqueue message workqueue function
81 *
82 * This function is registered as a kernel thread and is scheduled by the
83 * kernel handler.
84 */
85static irqreturn_t handle_event(int irq, void *p)
86{
87	struct rproc *rproc = p;
88
89	/* Process incoming buffers on all our vrings */
90	rproc_vq_interrupt(rproc, 0);
91	rproc_vq_interrupt(rproc, 1);
92
93	return IRQ_HANDLED;
94}
95
96/**
97 * da8xx_rproc_callback() - inbound virtqueue message handler
98 *
99 * This handler is invoked directly by the kernel whenever the remote
100 * core (DSP) has modified the state of a virtqueue.  There is no
101 * "payload" message indicating the virtqueue index as is the case with
102 * mailbox-based implementations on OMAP4.  As such, this handler "polls"
103 * each known virtqueue index for every invocation.
104 */
105static irqreturn_t da8xx_rproc_callback(int irq, void *p)
106{
107	struct rproc *rproc = p;
108	struct da8xx_rproc *drproc = rproc->priv;
109	u32 chipsig;
110
111	chipsig = readl(drproc->chipsig);
112	if (chipsig & SYSCFG_CHIPSIG0) {
113		/* Clear interrupt level source */
114		writel(SYSCFG_CHIPSIG0, drproc->chipsig + 4);
115
116		/*
117		 * ACK intr to AINTC.
118		 *
119		 * It has already been ack'ed by the kernel before calling
120		 * this function, but since the ARM<->DSP interrupts in the
121		 * CHIPSIG register are "level" instead of "pulse" variety,
122		 * we need to ack it after taking down the level else we'll
123		 * be called again immediately after returning.
124		 */
125		drproc->ack_fxn(drproc->irq_data);
126
127		return IRQ_WAKE_THREAD;
128	}
129
130	return IRQ_HANDLED;
131}
132
133static int da8xx_rproc_start(struct rproc *rproc)
134{
135	struct device *dev = rproc->dev.parent;
136	struct da8xx_rproc *drproc = rproc->priv;
137	struct clk *dsp_clk = drproc->dsp_clk;
138	struct reset_control *dsp_reset = drproc->dsp_reset;
139	int ret;
140
141	/* hw requires the start (boot) address be on 1KB boundary */
142	if (rproc->bootaddr & 0x3ff) {
143		dev_err(dev, "invalid boot address: must be aligned to 1KB\n");
144
145		return -EINVAL;
146	}
147
148	writel(rproc->bootaddr, drproc->bootreg);
149
150	ret = clk_prepare_enable(dsp_clk);
151	if (ret) {
152		dev_err(dev, "clk_prepare_enable() failed: %d\n", ret);
153		return ret;
154	}
155
156	ret = reset_control_deassert(dsp_reset);
157	if (ret) {
158		dev_err(dev, "reset_control_deassert() failed: %d\n", ret);
159		clk_disable_unprepare(dsp_clk);
160		return ret;
161	}
162
163	return 0;
164}
165
166static int da8xx_rproc_stop(struct rproc *rproc)
167{
168	struct da8xx_rproc *drproc = rproc->priv;
169	struct device *dev = rproc->dev.parent;
170	int ret;
171
172	ret = reset_control_assert(drproc->dsp_reset);
173	if (ret) {
174		dev_err(dev, "reset_control_assert() failed: %d\n", ret);
175		return ret;
176	}
177
178	clk_disable_unprepare(drproc->dsp_clk);
179
180	return 0;
181}
182
183/* kick a virtqueue */
184static void da8xx_rproc_kick(struct rproc *rproc, int vqid)
185{
186	struct da8xx_rproc *drproc = rproc->priv;
187
188	/* Interrupt remote proc */
189	writel(SYSCFG_CHIPSIG2, drproc->chipsig);
190}
191
192static const struct rproc_ops da8xx_rproc_ops = {
193	.start = da8xx_rproc_start,
194	.stop = da8xx_rproc_stop,
195	.kick = da8xx_rproc_kick,
196};
197
198static int da8xx_rproc_get_internal_memories(struct platform_device *pdev,
199					     struct da8xx_rproc *drproc)
200{
201	static const char * const mem_names[] = {"l2sram", "l1pram", "l1dram"};
202	int num_mems = ARRAY_SIZE(mem_names);
203	struct device *dev = &pdev->dev;
204	struct resource *res;
205	int i;
206
207	drproc->mem = devm_kcalloc(dev, num_mems, sizeof(*drproc->mem),
208				   GFP_KERNEL);
209	if (!drproc->mem)
210		return -ENOMEM;
211
212	for (i = 0; i < num_mems; i++) {
213		res = platform_get_resource_byname(pdev, IORESOURCE_MEM,
214						   mem_names[i]);
215		drproc->mem[i].cpu_addr = devm_ioremap_resource(dev, res);
216		if (IS_ERR(drproc->mem[i].cpu_addr)) {
217			dev_err(dev, "failed to parse and map %s memory\n",
218				mem_names[i]);
219			return PTR_ERR(drproc->mem[i].cpu_addr);
220		}
221		drproc->mem[i].bus_addr = res->start;
222		drproc->mem[i].dev_addr =
223				res->start & DA8XX_RPROC_LOCAL_ADDRESS_MASK;
224		drproc->mem[i].size = resource_size(res);
225
226		dev_dbg(dev, "memory %8s: bus addr %pa size 0x%zx va %p da 0x%x\n",
227			mem_names[i], &drproc->mem[i].bus_addr,
228			drproc->mem[i].size, drproc->mem[i].cpu_addr,
229			drproc->mem[i].dev_addr);
230	}
231	drproc->num_mems = num_mems;
232
233	return 0;
234}
235
236static int da8xx_rproc_probe(struct platform_device *pdev)
237{
238	struct device *dev = &pdev->dev;
239	struct da8xx_rproc *drproc;
240	struct rproc *rproc;
241	struct irq_data *irq_data;
242	struct resource *bootreg_res;
243	struct resource *chipsig_res;
244	struct clk *dsp_clk;
245	struct reset_control *dsp_reset;
246	void __iomem *chipsig;
247	void __iomem *bootreg;
248	int irq;
249	int ret;
250
251	irq = platform_get_irq(pdev, 0);
252	if (irq < 0)
253		return irq;
254
255	irq_data = irq_get_irq_data(irq);
256	if (!irq_data) {
257		dev_err(dev, "irq_get_irq_data(%d): NULL\n", irq);
258		return -EINVAL;
259	}
260
261	bootreg_res = platform_get_resource_byname(pdev, IORESOURCE_MEM,
262						   "host1cfg");
263	bootreg = devm_ioremap_resource(dev, bootreg_res);
264	if (IS_ERR(bootreg))
265		return PTR_ERR(bootreg);
266
267	chipsig_res = platform_get_resource_byname(pdev, IORESOURCE_MEM,
268						   "chipsig");
269	chipsig = devm_ioremap_resource(dev, chipsig_res);
270	if (IS_ERR(chipsig))
271		return PTR_ERR(chipsig);
272
273	dsp_clk = devm_clk_get(dev, NULL);
274	if (IS_ERR(dsp_clk)) {
275		dev_err(dev, "clk_get error: %ld\n", PTR_ERR(dsp_clk));
276
277		return PTR_ERR(dsp_clk);
278	}
279
280	dsp_reset = devm_reset_control_get_exclusive(dev, NULL);
281	if (IS_ERR(dsp_reset)) {
282		if (PTR_ERR(dsp_reset) != -EPROBE_DEFER)
283			dev_err(dev, "unable to get reset control: %ld\n",
284				PTR_ERR(dsp_reset));
285
286		return PTR_ERR(dsp_reset);
287	}
288
289	if (dev->of_node) {
290		ret = of_reserved_mem_device_init(dev);
291		if (ret) {
292			dev_err(dev, "device does not have specific CMA pool: %d\n",
293				ret);
294			return ret;
295		}
296	}
297
298	rproc = rproc_alloc(dev, "dsp", &da8xx_rproc_ops, da8xx_fw_name,
299		sizeof(*drproc));
300	if (!rproc) {
301		ret = -ENOMEM;
302		goto free_mem;
303	}
304
305	/* error recovery is not supported at present */
306	rproc->recovery_disabled = true;
307
308	drproc = rproc->priv;
309	drproc->rproc = rproc;
310	drproc->dsp_clk = dsp_clk;
311	drproc->dsp_reset = dsp_reset;
312	rproc->has_iommu = false;
313
314	ret = da8xx_rproc_get_internal_memories(pdev, drproc);
315	if (ret)
316		goto free_rproc;
317
318	platform_set_drvdata(pdev, rproc);
319
320	/* everything the ISR needs is now setup, so hook it up */
321	ret = devm_request_threaded_irq(dev, irq, da8xx_rproc_callback,
322					handle_event, 0, "da8xx-remoteproc",
323					rproc);
324	if (ret) {
325		dev_err(dev, "devm_request_threaded_irq error: %d\n", ret);
326		goto free_rproc;
327	}
328
329	/*
330	 * rproc_add() can end up enabling the DSP's clk with the DSP
331	 * *not* in reset, but da8xx_rproc_start() needs the DSP to be
332	 * held in reset at the time it is called.
333	 */
334	ret = reset_control_assert(dsp_reset);
335	if (ret)
336		goto free_rproc;
337
338	drproc->chipsig = chipsig;
339	drproc->bootreg = bootreg;
340	drproc->ack_fxn = irq_data->chip->irq_ack;
341	drproc->irq_data = irq_data;
342	drproc->irq = irq;
343
344	ret = rproc_add(rproc);
345	if (ret) {
346		dev_err(dev, "rproc_add failed: %d\n", ret);
347		goto free_rproc;
348	}
349
350	return 0;
351
352free_rproc:
353	rproc_free(rproc);
354free_mem:
355	if (dev->of_node)
356		of_reserved_mem_device_release(dev);
357	return ret;
358}
359
360static void da8xx_rproc_remove(struct platform_device *pdev)
361{
362	struct rproc *rproc = platform_get_drvdata(pdev);
363	struct da8xx_rproc *drproc = rproc->priv;
364	struct device *dev = &pdev->dev;
365
366	/*
367	 * The devm subsystem might end up releasing things before
368	 * freeing the irq, thus allowing an interrupt to sneak in while
369	 * the device is being removed.  This should prevent that.
370	 */
371	disable_irq(drproc->irq);
372
373	rproc_del(rproc);
374	rproc_free(rproc);
375	if (dev->of_node)
376		of_reserved_mem_device_release(dev);
377}
378
379static const struct of_device_id davinci_rproc_of_match[] __maybe_unused = {
380	{ .compatible = "ti,da850-dsp", },
381	{ /* sentinel */ },
382};
383MODULE_DEVICE_TABLE(of, davinci_rproc_of_match);
384
385static struct platform_driver da8xx_rproc_driver = {
386	.probe = da8xx_rproc_probe,
387	.remove_new = da8xx_rproc_remove,
388	.driver = {
389		.name = "davinci-rproc",
390		.of_match_table = of_match_ptr(davinci_rproc_of_match),
391	},
392};
393
394module_platform_driver(da8xx_rproc_driver);
395
396MODULE_LICENSE("GPL v2");
397MODULE_DESCRIPTION("DA8XX Remote Processor control driver");
398