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11#include <linux/device.h>
12#include <linux/err.h>
13#include <linux/interrupt.h>
14#include <linux/io.h>
15#include <linux/kfifo.h>
16#include <linux/mailbox_controller.h>
17#include <linux/module.h>
18#include <linux/platform_device.h>
19#include <linux/slab.h>
20
21#define MBOX_CHAN_MAX 32
22
23#define MBOX_TX 0x1
24
25
26#define MBOX_MSG_LEN 8
27
28
29#define MBOX_OFF(m) (0x40 * (m))
30#define MBOX_MODE_REG(m) (MBOX_OFF(m) + 0x0)
31#define MBOX_DATA_REG(m) (MBOX_OFF(m) + 0x4)
32
33#define MBOX_STATE_MASK (0xF << 4)
34#define MBOX_STATE_IDLE (0x1 << 4)
35#define MBOX_STATE_TX (0x2 << 4)
36#define MBOX_STATE_RX (0x4 << 4)
37#define MBOX_STATE_ACK (0x8 << 4)
38#define MBOX_ACK_CONFIG_MASK (0x1 << 0)
39#define MBOX_ACK_AUTOMATIC (0x1 << 0)
40#define MBOX_ACK_IRQ (0x0 << 0)
41
42
43#define ACK_INT_RAW_REG(i) ((i) + 0x400)
44#define ACK_INT_MSK_REG(i) ((i) + 0x404)
45#define ACK_INT_STAT_REG(i) ((i) + 0x408)
46#define ACK_INT_CLR_REG(i) ((i) + 0x40c)
47#define ACK_INT_ENA_REG(i) ((i) + 0x500)
48#define ACK_INT_DIS_REG(i) ((i) + 0x504)
49#define DST_INT_RAW_REG(i) ((i) + 0x420)
50
51
52struct hi6220_mbox_chan {
53
54
55
56
57
58
59
60
61 unsigned int dir, dst_irq, ack_irq;
62 unsigned int slot;
63
64 struct hi6220_mbox *parent;
65};
66
67struct hi6220_mbox {
68 struct device *dev;
69
70 int irq;
71
72
73 bool tx_irq_mode;
74
75
76 void __iomem *ipc;
77
78
79 void __iomem *base;
80
81 unsigned int chan_num;
82 struct hi6220_mbox_chan *mchan;
83
84 void *irq_map_chan[MBOX_CHAN_MAX];
85 struct mbox_chan *chan;
86 struct mbox_controller controller;
87};
88
89static void mbox_set_state(struct hi6220_mbox *mbox,
90 unsigned int slot, u32 val)
91{
92 u32 status;
93
94 status = readl(mbox->base + MBOX_MODE_REG(slot));
95 status = (status & ~MBOX_STATE_MASK) | val;
96 writel(status, mbox->base + MBOX_MODE_REG(slot));
97}
98
99static void mbox_set_mode(struct hi6220_mbox *mbox,
100 unsigned int slot, u32 val)
101{
102 u32 mode;
103
104 mode = readl(mbox->base + MBOX_MODE_REG(slot));
105 mode = (mode & ~MBOX_ACK_CONFIG_MASK) | val;
106 writel(mode, mbox->base + MBOX_MODE_REG(slot));
107}
108
109static bool hi6220_mbox_last_tx_done(struct mbox_chan *chan)
110{
111 struct hi6220_mbox_chan *mchan = chan->con_priv;
112 struct hi6220_mbox *mbox = mchan->parent;
113 u32 state;
114
115
116 BUG_ON(mbox->tx_irq_mode);
117
118 state = readl(mbox->base + MBOX_MODE_REG(mchan->slot));
119 return ((state & MBOX_STATE_MASK) == MBOX_STATE_IDLE);
120}
121
122static int hi6220_mbox_send_data(struct mbox_chan *chan, void *msg)
123{
124 struct hi6220_mbox_chan *mchan = chan->con_priv;
125 struct hi6220_mbox *mbox = mchan->parent;
126 unsigned int slot = mchan->slot;
127 u32 *buf = msg;
128 int i;
129
130
131 mchan->dir = MBOX_TX;
132
133 mbox_set_state(mbox, slot, MBOX_STATE_TX);
134
135 if (mbox->tx_irq_mode)
136 mbox_set_mode(mbox, slot, MBOX_ACK_IRQ);
137 else
138 mbox_set_mode(mbox, slot, MBOX_ACK_AUTOMATIC);
139
140 for (i = 0; i < MBOX_MSG_LEN; i++)
141 writel(buf[i], mbox->base + MBOX_DATA_REG(slot) + i * 4);
142
143
144 writel(BIT(mchan->dst_irq), DST_INT_RAW_REG(mbox->ipc));
145 return 0;
146}
147
148static irqreturn_t hi6220_mbox_interrupt(int irq, void *p)
149{
150 struct hi6220_mbox *mbox = p;
151 struct hi6220_mbox_chan *mchan;
152 struct mbox_chan *chan;
153 unsigned int state, intr_bit, i;
154 u32 msg[MBOX_MSG_LEN];
155
156 state = readl(ACK_INT_STAT_REG(mbox->ipc));
157 if (!state) {
158 dev_warn(mbox->dev, "%s: spurious interrupt\n",
159 __func__);
160 return IRQ_HANDLED;
161 }
162
163 while (state) {
164 intr_bit = __ffs(state);
165 state &= (state - 1);
166
167 chan = mbox->irq_map_chan[intr_bit];
168 if (!chan) {
169 dev_warn(mbox->dev, "%s: unexpected irq vector %d\n",
170 __func__, intr_bit);
171 continue;
172 }
173
174 mchan = chan->con_priv;
175 if (mchan->dir == MBOX_TX)
176 mbox_chan_txdone(chan, 0);
177 else {
178 for (i = 0; i < MBOX_MSG_LEN; i++)
179 msg[i] = readl(mbox->base +
180 MBOX_DATA_REG(mchan->slot) + i * 4);
181
182 mbox_chan_received_data(chan, (void *)msg);
183 }
184
185
186 writel(BIT(mchan->ack_irq), ACK_INT_CLR_REG(mbox->ipc));
187 mbox_set_state(mbox, mchan->slot, MBOX_STATE_IDLE);
188 }
189
190 return IRQ_HANDLED;
191}
192
193static int hi6220_mbox_startup(struct mbox_chan *chan)
194{
195 struct hi6220_mbox_chan *mchan = chan->con_priv;
196 struct hi6220_mbox *mbox = mchan->parent;
197
198 mchan->dir = 0;
199
200
201 writel(BIT(mchan->ack_irq), ACK_INT_ENA_REG(mbox->ipc));
202 return 0;
203}
204
205static void hi6220_mbox_shutdown(struct mbox_chan *chan)
206{
207 struct hi6220_mbox_chan *mchan = chan->con_priv;
208 struct hi6220_mbox *mbox = mchan->parent;
209
210
211 writel(BIT(mchan->ack_irq), ACK_INT_DIS_REG(mbox->ipc));
212 mbox->irq_map_chan[mchan->ack_irq] = NULL;
213}
214
215static const struct mbox_chan_ops hi6220_mbox_ops = {
216 .send_data = hi6220_mbox_send_data,
217 .startup = hi6220_mbox_startup,
218 .shutdown = hi6220_mbox_shutdown,
219 .last_tx_done = hi6220_mbox_last_tx_done,
220};
221
222static struct mbox_chan *hi6220_mbox_xlate(struct mbox_controller *controller,
223 const struct of_phandle_args *spec)
224{
225 struct hi6220_mbox *mbox = dev_get_drvdata(controller->dev);
226 struct hi6220_mbox_chan *mchan;
227 struct mbox_chan *chan;
228 unsigned int i = spec->args[0];
229 unsigned int dst_irq = spec->args[1];
230 unsigned int ack_irq = spec->args[2];
231
232
233 if (i >= mbox->chan_num || dst_irq >= mbox->chan_num ||
234 ack_irq >= mbox->chan_num) {
235 dev_err(mbox->dev,
236 "Invalid channel idx %d dst_irq %d ack_irq %d\n",
237 i, dst_irq, ack_irq);
238 return ERR_PTR(-EINVAL);
239 }
240
241
242 chan = &mbox->chan[i];
243 if (mbox->irq_map_chan[ack_irq] == (void *)chan) {
244 dev_err(mbox->dev, "Channel in use\n");
245 return ERR_PTR(-EBUSY);
246 }
247
248 mchan = chan->con_priv;
249 mchan->dst_irq = dst_irq;
250 mchan->ack_irq = ack_irq;
251
252 mbox->irq_map_chan[ack_irq] = (void *)chan;
253 return chan;
254}
255
256static const struct of_device_id hi6220_mbox_of_match[] = {
257 { .compatible = "hisilicon,hi6220-mbox", },
258 {},
259};
260MODULE_DEVICE_TABLE(of, hi6220_mbox_of_match);
261
262static int hi6220_mbox_probe(struct platform_device *pdev)
263{
264 struct device_node *node = pdev->dev.of_node;
265 struct device *dev = &pdev->dev;
266 struct hi6220_mbox *mbox;
267 struct resource *res;
268 int i, err;
269
270 mbox = devm_kzalloc(dev, sizeof(*mbox), GFP_KERNEL);
271 if (!mbox)
272 return -ENOMEM;
273
274 mbox->dev = dev;
275 mbox->chan_num = MBOX_CHAN_MAX;
276 mbox->mchan = devm_kcalloc(dev,
277 mbox->chan_num, sizeof(*mbox->mchan), GFP_KERNEL);
278 if (!mbox->mchan)
279 return -ENOMEM;
280
281 mbox->chan = devm_kcalloc(dev,
282 mbox->chan_num, sizeof(*mbox->chan), GFP_KERNEL);
283 if (!mbox->chan)
284 return -ENOMEM;
285
286 mbox->irq = platform_get_irq(pdev, 0);
287 if (mbox->irq < 0)
288 return mbox->irq;
289
290 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
291 mbox->ipc = devm_ioremap_resource(dev, res);
292 if (IS_ERR(mbox->ipc)) {
293 dev_err(dev, "ioremap ipc failed\n");
294 return PTR_ERR(mbox->ipc);
295 }
296
297 res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
298 mbox->base = devm_ioremap_resource(dev, res);
299 if (IS_ERR(mbox->base)) {
300 dev_err(dev, "ioremap buffer failed\n");
301 return PTR_ERR(mbox->base);
302 }
303
304 err = devm_request_irq(dev, mbox->irq, hi6220_mbox_interrupt, 0,
305 dev_name(dev), mbox);
306 if (err) {
307 dev_err(dev, "Failed to register a mailbox IRQ handler: %d\n",
308 err);
309 return -ENODEV;
310 }
311
312 mbox->controller.dev = dev;
313 mbox->controller.chans = &mbox->chan[0];
314 mbox->controller.num_chans = mbox->chan_num;
315 mbox->controller.ops = &hi6220_mbox_ops;
316 mbox->controller.of_xlate = hi6220_mbox_xlate;
317
318 for (i = 0; i < mbox->chan_num; i++) {
319 mbox->chan[i].con_priv = &mbox->mchan[i];
320 mbox->irq_map_chan[i] = NULL;
321
322 mbox->mchan[i].parent = mbox;
323 mbox->mchan[i].slot = i;
324 }
325
326
327 writel(0x0, ACK_INT_MSK_REG(mbox->ipc));
328 writel(~0x0, ACK_INT_CLR_REG(mbox->ipc));
329
330
331 if (of_find_property(node, "hi6220,mbox-tx-noirq", NULL))
332 mbox->tx_irq_mode = false;
333 else
334 mbox->tx_irq_mode = true;
335
336 if (mbox->tx_irq_mode)
337 mbox->controller.txdone_irq = true;
338 else {
339 mbox->controller.txdone_poll = true;
340 mbox->controller.txpoll_period = 5;
341 }
342
343 err = devm_mbox_controller_register(dev, &mbox->controller);
344 if (err) {
345 dev_err(dev, "Failed to register mailbox %d\n", err);
346 return err;
347 }
348
349 platform_set_drvdata(pdev, mbox);
350 dev_info(dev, "Mailbox enabled\n");
351 return 0;
352}
353
354static struct platform_driver hi6220_mbox_driver = {
355 .driver = {
356 .name = "hi6220-mbox",
357 .of_match_table = hi6220_mbox_of_match,
358 },
359 .probe = hi6220_mbox_probe,
360};
361
362static int __init hi6220_mbox_init(void)
363{
364 return platform_driver_register(&hi6220_mbox_driver);
365}
366core_initcall(hi6220_mbox_init);
367
368static void __exit hi6220_mbox_exit(void)
369{
370 platform_driver_unregister(&hi6220_mbox_driver);
371}
372module_exit(hi6220_mbox_exit);
373
374MODULE_AUTHOR("Leo Yan <leo.yan@linaro.org>");
375MODULE_DESCRIPTION("Hi6220 mailbox driver");
376MODULE_LICENSE("GPL v2");
377
