blob: 613722db5daf314fd376e96ec18209b7d2132fd5 [file] [log] [blame]
Leo Yan9c384182016-02-15 21:50:24 +08001/*
2 * Hisilicon's Hi6220 mailbox driver
3 *
4 * Copyright (c) 2015 Hisilicon Limited.
5 * Copyright (c) 2015 Linaro Limited.
6 *
7 * Author: Leo Yan <leo.yan@linaro.org>
8 *
9 * This program is free software: you can redistribute it and/or modify
10 * it under the terms of the GNU General Public License as published by
11 * the Free Software Foundation, version 2 of the License.
12 *
13 * This program is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 * GNU General Public License for more details.
17 *
18 */
19
20#include <linux/device.h>
21#include <linux/err.h>
22#include <linux/interrupt.h>
23#include <linux/io.h>
24#include <linux/kfifo.h>
25#include <linux/mailbox_controller.h>
26#include <linux/module.h>
27#include <linux/platform_device.h>
28#include <linux/slab.h>
29
30#define MBOX_CHAN_MAX 32
31
32#define MBOX_TX 0x1
33
34/* Mailbox message length: 8 words */
35#define MBOX_MSG_LEN 8
36
37/* Mailbox Registers */
38#define MBOX_OFF(m) (0x40 * (m))
39#define MBOX_MODE_REG(m) (MBOX_OFF(m) + 0x0)
40#define MBOX_DATA_REG(m) (MBOX_OFF(m) + 0x4)
41
42#define MBOX_STATE_MASK (0xF << 4)
43#define MBOX_STATE_IDLE (0x1 << 4)
44#define MBOX_STATE_TX (0x2 << 4)
45#define MBOX_STATE_RX (0x4 << 4)
46#define MBOX_STATE_ACK (0x8 << 4)
47#define MBOX_ACK_CONFIG_MASK (0x1 << 0)
48#define MBOX_ACK_AUTOMATIC (0x1 << 0)
49#define MBOX_ACK_IRQ (0x0 << 0)
50
51/* IPC registers */
52#define ACK_INT_RAW_REG(i) ((i) + 0x400)
53#define ACK_INT_MSK_REG(i) ((i) + 0x404)
54#define ACK_INT_STAT_REG(i) ((i) + 0x408)
55#define ACK_INT_CLR_REG(i) ((i) + 0x40c)
56#define ACK_INT_ENA_REG(i) ((i) + 0x500)
57#define ACK_INT_DIS_REG(i) ((i) + 0x504)
58#define DST_INT_RAW_REG(i) ((i) + 0x420)
59
60
61struct hi6220_mbox_chan {
62
63 /*
64 * Description for channel's hardware info:
65 * - direction: tx or rx
66 * - dst irq: peer core's irq number
67 * - ack irq: local irq number
68 * - slot number
69 */
70 unsigned int dir, dst_irq, ack_irq;
71 unsigned int slot;
72
73 struct hi6220_mbox *parent;
74};
75
76struct hi6220_mbox {
77 struct device *dev;
78
79 int irq;
80
81 /* flag of enabling tx's irq mode */
82 bool tx_irq_mode;
83
84 /* region for ipc event */
85 void __iomem *ipc;
86
87 /* region for mailbox */
88 void __iomem *base;
89
90 unsigned int chan_num;
91 struct hi6220_mbox_chan *mchan;
92
93 void *irq_map_chan[MBOX_CHAN_MAX];
94 struct mbox_chan *chan;
95 struct mbox_controller controller;
96};
97
98static void mbox_set_state(struct hi6220_mbox *mbox,
99 unsigned int slot, u32 val)
100{
101 u32 status;
102
103 status = readl(mbox->base + MBOX_MODE_REG(slot));
104 status = (status & ~MBOX_STATE_MASK) | val;
105 writel(status, mbox->base + MBOX_MODE_REG(slot));
106}
107
108static void mbox_set_mode(struct hi6220_mbox *mbox,
109 unsigned int slot, u32 val)
110{
111 u32 mode;
112
113 mode = readl(mbox->base + MBOX_MODE_REG(slot));
114 mode = (mode & ~MBOX_ACK_CONFIG_MASK) | val;
115 writel(mode, mbox->base + MBOX_MODE_REG(slot));
116}
117
118static bool hi6220_mbox_last_tx_done(struct mbox_chan *chan)
119{
120 struct hi6220_mbox_chan *mchan = chan->con_priv;
121 struct hi6220_mbox *mbox = mchan->parent;
122 u32 state;
123
124 /* Only set idle state for polling mode */
125 BUG_ON(mbox->tx_irq_mode);
126
127 state = readl(mbox->base + MBOX_MODE_REG(mchan->slot));
128 return ((state & MBOX_STATE_MASK) == MBOX_STATE_IDLE);
129}
130
131static int hi6220_mbox_send_data(struct mbox_chan *chan, void *msg)
132{
133 struct hi6220_mbox_chan *mchan = chan->con_priv;
134 struct hi6220_mbox *mbox = mchan->parent;
135 unsigned int slot = mchan->slot;
136 u32 *buf = msg;
137 int i;
138
139 /* indicate as a TX channel */
140 mchan->dir = MBOX_TX;
141
142 mbox_set_state(mbox, slot, MBOX_STATE_TX);
143
144 if (mbox->tx_irq_mode)
145 mbox_set_mode(mbox, slot, MBOX_ACK_IRQ);
146 else
147 mbox_set_mode(mbox, slot, MBOX_ACK_AUTOMATIC);
148
149 for (i = 0; i < MBOX_MSG_LEN; i++)
150 writel(buf[i], mbox->base + MBOX_DATA_REG(slot) + i * 4);
151
152 /* trigger remote request */
153 writel(BIT(mchan->dst_irq), DST_INT_RAW_REG(mbox->ipc));
154 return 0;
155}
156
157static irqreturn_t hi6220_mbox_interrupt(int irq, void *p)
158{
159 struct hi6220_mbox *mbox = p;
160 struct hi6220_mbox_chan *mchan;
161 struct mbox_chan *chan;
162 unsigned int state, intr_bit, i;
163 u32 msg[MBOX_MSG_LEN];
164
165 state = readl(ACK_INT_STAT_REG(mbox->ipc));
166 if (!state) {
167 dev_warn(mbox->dev, "%s: spurious interrupt\n",
168 __func__);
169 return IRQ_HANDLED;
170 }
171
172 while (state) {
173 intr_bit = __ffs(state);
174 state &= (state - 1);
175
176 chan = mbox->irq_map_chan[intr_bit];
177 if (!chan) {
178 dev_warn(mbox->dev, "%s: unexpected irq vector %d\n",
179 __func__, intr_bit);
180 continue;
181 }
182
183 mchan = chan->con_priv;
184 if (mchan->dir == MBOX_TX)
185 mbox_chan_txdone(chan, 0);
186 else {
187 for (i = 0; i < MBOX_MSG_LEN; i++)
188 msg[i] = readl(mbox->base +
189 MBOX_DATA_REG(mchan->slot) + i * 4);
190
191 mbox_chan_received_data(chan, (void *)msg);
192 }
193
194 /* clear IRQ source */
195 writel(BIT(mchan->ack_irq), ACK_INT_CLR_REG(mbox->ipc));
196 mbox_set_state(mbox, mchan->slot, MBOX_STATE_IDLE);
197 }
198
199 return IRQ_HANDLED;
200}
201
202static int hi6220_mbox_startup(struct mbox_chan *chan)
203{
204 struct hi6220_mbox_chan *mchan = chan->con_priv;
205 struct hi6220_mbox *mbox = mchan->parent;
206
207 mchan->dir = 0;
208
209 /* enable interrupt */
210 writel(BIT(mchan->ack_irq), ACK_INT_ENA_REG(mbox->ipc));
211 return 0;
212}
213
214static void hi6220_mbox_shutdown(struct mbox_chan *chan)
215{
216 struct hi6220_mbox_chan *mchan = chan->con_priv;
217 struct hi6220_mbox *mbox = mchan->parent;
218
219 /* disable interrupt */
220 writel(BIT(mchan->ack_irq), ACK_INT_DIS_REG(mbox->ipc));
221 mbox->irq_map_chan[mchan->ack_irq] = NULL;
222}
223
224static struct mbox_chan_ops hi6220_mbox_ops = {
225 .send_data = hi6220_mbox_send_data,
226 .startup = hi6220_mbox_startup,
227 .shutdown = hi6220_mbox_shutdown,
228 .last_tx_done = hi6220_mbox_last_tx_done,
229};
230
231static struct mbox_chan *hi6220_mbox_xlate(struct mbox_controller *controller,
232 const struct of_phandle_args *spec)
233{
234 struct hi6220_mbox *mbox = dev_get_drvdata(controller->dev);
235 struct hi6220_mbox_chan *mchan;
236 struct mbox_chan *chan;
237 unsigned int i = spec->args[0];
238 unsigned int dst_irq = spec->args[1];
239 unsigned int ack_irq = spec->args[2];
240
241 /* Bounds checking */
242 if (i >= mbox->chan_num || dst_irq >= mbox->chan_num ||
243 ack_irq >= mbox->chan_num) {
244 dev_err(mbox->dev,
245 "Invalid channel idx %d dst_irq %d ack_irq %d\n",
246 i, dst_irq, ack_irq);
247 return ERR_PTR(-EINVAL);
248 }
249
250 /* Is requested channel free? */
251 chan = &mbox->chan[i];
252 if (mbox->irq_map_chan[ack_irq] == (void *)chan) {
253 dev_err(mbox->dev, "Channel in use\n");
254 return ERR_PTR(-EBUSY);
255 }
256
257 mchan = chan->con_priv;
258 mchan->dst_irq = dst_irq;
259 mchan->ack_irq = ack_irq;
260
261 mbox->irq_map_chan[ack_irq] = (void *)chan;
262 return chan;
263}
264
265static const struct of_device_id hi6220_mbox_of_match[] = {
266 { .compatible = "hisilicon,hi6220-mbox", },
267 {},
268};
269MODULE_DEVICE_TABLE(of, hi6220_mbox_of_match);
270
271static int hi6220_mbox_probe(struct platform_device *pdev)
272{
273 struct device_node *node = pdev->dev.of_node;
274 struct device *dev = &pdev->dev;
275 struct hi6220_mbox *mbox;
276 struct resource *res;
277 int i, err;
278
279 mbox = devm_kzalloc(dev, sizeof(*mbox), GFP_KERNEL);
280 if (!mbox)
281 return -ENOMEM;
282
283 mbox->dev = dev;
284 mbox->chan_num = MBOX_CHAN_MAX;
285 mbox->mchan = devm_kzalloc(dev,
286 mbox->chan_num * sizeof(*mbox->mchan), GFP_KERNEL);
287 if (!mbox->mchan)
288 return -ENOMEM;
289
290 mbox->chan = devm_kzalloc(dev,
291 mbox->chan_num * sizeof(*mbox->chan), GFP_KERNEL);
292 if (!mbox->chan)
293 return -ENOMEM;
294
295 mbox->irq = platform_get_irq(pdev, 0);
296 if (mbox->irq < 0)
297 return mbox->irq;
298
299 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
300 mbox->ipc = devm_ioremap_resource(dev, res);
301 if (IS_ERR(mbox->ipc)) {
302 dev_err(dev, "ioremap ipc failed\n");
303 return PTR_ERR(mbox->ipc);
304 }
305
306 res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
307 mbox->base = devm_ioremap_resource(dev, res);
308 if (IS_ERR(mbox->base)) {
309 dev_err(dev, "ioremap buffer failed\n");
310 return PTR_ERR(mbox->base);
311 }
312
313 err = devm_request_irq(dev, mbox->irq, hi6220_mbox_interrupt, 0,
314 dev_name(dev), mbox);
315 if (err) {
316 dev_err(dev, "Failed to register a mailbox IRQ handler: %d\n",
317 err);
318 return -ENODEV;
319 }
320
321 mbox->controller.dev = dev;
322 mbox->controller.chans = &mbox->chan[0];
323 mbox->controller.num_chans = mbox->chan_num;
324 mbox->controller.ops = &hi6220_mbox_ops;
325 mbox->controller.of_xlate = hi6220_mbox_xlate;
326
327 for (i = 0; i < mbox->chan_num; i++) {
328 mbox->chan[i].con_priv = &mbox->mchan[i];
329 mbox->irq_map_chan[i] = NULL;
330
331 mbox->mchan[i].parent = mbox;
332 mbox->mchan[i].slot = i;
333 }
334
335 /* mask and clear all interrupt vectors */
336 writel(0x0, ACK_INT_MSK_REG(mbox->ipc));
337 writel(~0x0, ACK_INT_CLR_REG(mbox->ipc));
338
339 /* use interrupt for tx's ack */
340 if (of_find_property(node, "hi6220,mbox-tx-noirq", NULL))
341 mbox->tx_irq_mode = false;
342 else
343 mbox->tx_irq_mode = true;
344
345 if (mbox->tx_irq_mode)
346 mbox->controller.txdone_irq = true;
347 else {
348 mbox->controller.txdone_poll = true;
349 mbox->controller.txpoll_period = 5;
350 }
351
352 err = mbox_controller_register(&mbox->controller);
353 if (err) {
354 dev_err(dev, "Failed to register mailbox %d\n", err);
355 return err;
356 }
357
358 platform_set_drvdata(pdev, mbox);
359 dev_info(dev, "Mailbox enabled\n");
360 return 0;
361}
362
363static int hi6220_mbox_remove(struct platform_device *pdev)
364{
365 struct hi6220_mbox *mbox = platform_get_drvdata(pdev);
366
367 mbox_controller_unregister(&mbox->controller);
368 return 0;
369}
370
371static struct platform_driver hi6220_mbox_driver = {
372 .driver = {
373 .name = "hi6220-mbox",
374 .owner = THIS_MODULE,
375 .of_match_table = hi6220_mbox_of_match,
376 },
377 .probe = hi6220_mbox_probe,
378 .remove = hi6220_mbox_remove,
379};
380
381static int __init hi6220_mbox_init(void)
382{
383 return platform_driver_register(&hi6220_mbox_driver);
384}
385core_initcall(hi6220_mbox_init);
386
387static void __exit hi6220_mbox_exit(void)
388{
389 platform_driver_unregister(&hi6220_mbox_driver);
390}
391module_exit(hi6220_mbox_exit);
392
393MODULE_AUTHOR("Leo Yan <leo.yan@linaro.org>");
394MODULE_DESCRIPTION("Hi6220 mailbox driver");
395MODULE_LICENSE("GPL v2");