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 clk *dsp_clk;
243	struct reset_control *dsp_reset;
244	void __iomem *chipsig;
245	void __iomem *bootreg;
246	int irq;
247	int ret;
248
249	irq = platform_get_irq(pdev, 0);
250	if (irq < 0)
251		return irq;
252
253	irq_data = irq_get_irq_data(irq);
254	if (!irq_data)
255		return dev_err_probe(dev, -EINVAL, "irq_get_irq_data(%d): NULL\n", irq);
256
257	bootreg = devm_platform_ioremap_resource_byname(pdev, "host1cfg");
258	if (IS_ERR(bootreg))
259		return PTR_ERR(bootreg);
260
261	chipsig = devm_platform_ioremap_resource_byname(pdev, "chipsig");
262	if (IS_ERR(chipsig))
263		return PTR_ERR(chipsig);
264
265	dsp_clk = devm_clk_get(dev, NULL);
266	if (IS_ERR(dsp_clk))
267		return dev_err_probe(dev, PTR_ERR(dsp_clk), "clk_get error\n");
268
269	dsp_reset = devm_reset_control_get_exclusive(dev, NULL);
270	if (IS_ERR(dsp_reset))
271		return dev_err_probe(dev, PTR_ERR(dsp_reset), "unable to get reset control\n");
272
273	if (dev->of_node) {
274		ret = of_reserved_mem_device_init(dev);
275		if (ret)
276			return dev_err_probe(dev, ret, "device does not have specific CMA pool\n");
277	}
278
279	rproc = rproc_alloc(dev, "dsp", &da8xx_rproc_ops, da8xx_fw_name,
280		sizeof(*drproc));
281	if (!rproc) {
282		ret = -ENOMEM;
283		goto free_mem;
284	}
285
286	/* error recovery is not supported at present */
287	rproc->recovery_disabled = true;
288
289	drproc = rproc->priv;
290	drproc->rproc = rproc;
291	drproc->dsp_clk = dsp_clk;
292	drproc->dsp_reset = dsp_reset;
293	rproc->has_iommu = false;
294
295	ret = da8xx_rproc_get_internal_memories(pdev, drproc);
296	if (ret)
297		goto free_rproc;
298
299	platform_set_drvdata(pdev, rproc);
300
301	/* everything the ISR needs is now setup, so hook it up */
302	ret = devm_request_threaded_irq(dev, irq, da8xx_rproc_callback,
303					handle_event, 0, "da8xx-remoteproc",
304					rproc);
305	if (ret) {
306		dev_err(dev, "devm_request_threaded_irq error: %d\n", ret);
307		goto free_rproc;
308	}
309
310	/*
311	 * rproc_add() can end up enabling the DSP's clk with the DSP
312	 * *not* in reset, but da8xx_rproc_start() needs the DSP to be
313	 * held in reset at the time it is called.
314	 */
315	ret = reset_control_assert(dsp_reset);
316	if (ret)
317		goto free_rproc;
318
319	drproc->chipsig = chipsig;
320	drproc->bootreg = bootreg;
321	drproc->ack_fxn = irq_data->chip->irq_ack;
322	drproc->irq_data = irq_data;
323	drproc->irq = irq;
324
325	ret = rproc_add(rproc);
326	if (ret) {
327		dev_err(dev, "rproc_add failed: %d\n", ret);
328		goto free_rproc;
329	}
330
331	return 0;
332
333free_rproc:
334	rproc_free(rproc);
335free_mem:
336	if (dev->of_node)
337		of_reserved_mem_device_release(dev);
338	return ret;
339}
340
341static void da8xx_rproc_remove(struct platform_device *pdev)
342{
343	struct rproc *rproc = platform_get_drvdata(pdev);
344	struct da8xx_rproc *drproc = rproc->priv;
345	struct device *dev = &pdev->dev;
346
347	/*
348	 * The devm subsystem might end up releasing things before
349	 * freeing the irq, thus allowing an interrupt to sneak in while
350	 * the device is being removed.  This should prevent that.
351	 */
352	disable_irq(drproc->irq);
353
354	rproc_del(rproc);
355	rproc_free(rproc);
356	if (dev->of_node)
357		of_reserved_mem_device_release(dev);
358}
359
360static const struct of_device_id davinci_rproc_of_match[] __maybe_unused = {
361	{ .compatible = "ti,da850-dsp", },
362	{ /* sentinel */ },
363};
364MODULE_DEVICE_TABLE(of, davinci_rproc_of_match);
365
366static struct platform_driver da8xx_rproc_driver = {
367	.probe = da8xx_rproc_probe,
368	.remove = da8xx_rproc_remove,
369	.driver = {
370		.name = "davinci-rproc",
371		.of_match_table = of_match_ptr(davinci_rproc_of_match),
372	},
373};
374
375module_platform_driver(da8xx_rproc_driver);
376
377MODULE_LICENSE("GPL v2");
378MODULE_DESCRIPTION("DA8XX Remote Processor control driver");