2 * Hisilicon's Hi6220 mailbox driver
4 * Copyright (c) 2015 Hisilicon Limited.
5 * Copyright (c) 2015 Linaro Limited.
7 * Author: Leo Yan <leo.yan@linaro.org>
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.
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.
20 #include <linux/device.h>
21 #include <linux/err.h>
22 #include <linux/interrupt.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>
30 #define MBOX_CHAN_MAX 32
34 /* Mailbox message length: 8 words */
35 #define MBOX_MSG_LEN 8
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)
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)
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)
61 struct hi6220_mbox_chan
{
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
70 unsigned int dir
, dst_irq
, ack_irq
;
73 struct hi6220_mbox
*parent
;
81 /* flag of enabling tx's irq mode */
84 /* region for ipc event */
87 /* region for mailbox */
90 unsigned int chan_num
;
91 struct hi6220_mbox_chan
*mchan
;
93 void *irq_map_chan
[MBOX_CHAN_MAX
];
94 struct mbox_chan
*chan
;
95 struct mbox_controller controller
;
98 static void mbox_set_state(struct hi6220_mbox
*mbox
,
99 unsigned int slot
, u32 val
)
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
));
108 static void mbox_set_mode(struct hi6220_mbox
*mbox
,
109 unsigned int slot
, u32 val
)
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
));
118 static bool hi6220_mbox_last_tx_done(struct mbox_chan
*chan
)
120 struct hi6220_mbox_chan
*mchan
= chan
->con_priv
;
121 struct hi6220_mbox
*mbox
= mchan
->parent
;
124 /* Only set idle state for polling mode */
125 BUG_ON(mbox
->tx_irq_mode
);
127 state
= readl(mbox
->base
+ MBOX_MODE_REG(mchan
->slot
));
128 return ((state
& MBOX_STATE_MASK
) == MBOX_STATE_IDLE
);
131 static int hi6220_mbox_send_data(struct mbox_chan
*chan
, void *msg
)
133 struct hi6220_mbox_chan
*mchan
= chan
->con_priv
;
134 struct hi6220_mbox
*mbox
= mchan
->parent
;
135 unsigned int slot
= mchan
->slot
;
139 /* indicate as a TX channel */
140 mchan
->dir
= MBOX_TX
;
142 mbox_set_state(mbox
, slot
, MBOX_STATE_TX
);
144 if (mbox
->tx_irq_mode
)
145 mbox_set_mode(mbox
, slot
, MBOX_ACK_IRQ
);
147 mbox_set_mode(mbox
, slot
, MBOX_ACK_AUTOMATIC
);
149 for (i
= 0; i
< MBOX_MSG_LEN
; i
++)
150 writel(buf
[i
], mbox
->base
+ MBOX_DATA_REG(slot
) + i
* 4);
152 /* trigger remote request */
153 writel(BIT(mchan
->dst_irq
), DST_INT_RAW_REG(mbox
->ipc
));
157 static irqreturn_t
hi6220_mbox_interrupt(int irq
, void *p
)
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
];
165 state
= readl(ACK_INT_STAT_REG(mbox
->ipc
));
167 dev_warn(mbox
->dev
, "%s: spurious interrupt\n",
173 intr_bit
= __ffs(state
);
174 state
&= (state
- 1);
176 chan
= mbox
->irq_map_chan
[intr_bit
];
178 dev_warn(mbox
->dev
, "%s: unexpected irq vector %d\n",
183 mchan
= chan
->con_priv
;
184 if (mchan
->dir
== MBOX_TX
)
185 mbox_chan_txdone(chan
, 0);
187 for (i
= 0; i
< MBOX_MSG_LEN
; i
++)
188 msg
[i
] = readl(mbox
->base
+
189 MBOX_DATA_REG(mchan
->slot
) + i
* 4);
191 mbox_chan_received_data(chan
, (void *)msg
);
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
);
202 static int hi6220_mbox_startup(struct mbox_chan
*chan
)
204 struct hi6220_mbox_chan
*mchan
= chan
->con_priv
;
205 struct hi6220_mbox
*mbox
= mchan
->parent
;
209 /* enable interrupt */
210 writel(BIT(mchan
->ack_irq
), ACK_INT_ENA_REG(mbox
->ipc
));
214 static void hi6220_mbox_shutdown(struct mbox_chan
*chan
)
216 struct hi6220_mbox_chan
*mchan
= chan
->con_priv
;
217 struct hi6220_mbox
*mbox
= mchan
->parent
;
219 /* disable interrupt */
220 writel(BIT(mchan
->ack_irq
), ACK_INT_DIS_REG(mbox
->ipc
));
221 mbox
->irq_map_chan
[mchan
->ack_irq
] = NULL
;
224 static const 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
,
231 static struct mbox_chan
*hi6220_mbox_xlate(struct mbox_controller
*controller
,
232 const struct of_phandle_args
*spec
)
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];
241 /* Bounds checking */
242 if (i
>= mbox
->chan_num
|| dst_irq
>= mbox
->chan_num
||
243 ack_irq
>= mbox
->chan_num
) {
245 "Invalid channel idx %d dst_irq %d ack_irq %d\n",
246 i
, dst_irq
, ack_irq
);
247 return ERR_PTR(-EINVAL
);
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
);
257 mchan
= chan
->con_priv
;
258 mchan
->dst_irq
= dst_irq
;
259 mchan
->ack_irq
= ack_irq
;
261 mbox
->irq_map_chan
[ack_irq
] = (void *)chan
;
265 static const struct of_device_id hi6220_mbox_of_match
[] = {
266 { .compatible
= "hisilicon,hi6220-mbox", },
269 MODULE_DEVICE_TABLE(of
, hi6220_mbox_of_match
);
271 static int hi6220_mbox_probe(struct platform_device
*pdev
)
273 struct device_node
*node
= pdev
->dev
.of_node
;
274 struct device
*dev
= &pdev
->dev
;
275 struct hi6220_mbox
*mbox
;
276 struct resource
*res
;
279 mbox
= devm_kzalloc(dev
, sizeof(*mbox
), GFP_KERNEL
);
284 mbox
->chan_num
= MBOX_CHAN_MAX
;
285 mbox
->mchan
= devm_kcalloc(dev
,
286 mbox
->chan_num
, sizeof(*mbox
->mchan
), GFP_KERNEL
);
290 mbox
->chan
= devm_kcalloc(dev
,
291 mbox
->chan_num
, sizeof(*mbox
->chan
), GFP_KERNEL
);
295 mbox
->irq
= platform_get_irq(pdev
, 0);
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
);
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
);
313 err
= devm_request_irq(dev
, mbox
->irq
, hi6220_mbox_interrupt
, 0,
314 dev_name(dev
), mbox
);
316 dev_err(dev
, "Failed to register a mailbox IRQ handler: %d\n",
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
;
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
;
331 mbox
->mchan
[i
].parent
= mbox
;
332 mbox
->mchan
[i
].slot
= i
;
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
));
339 /* use interrupt for tx's ack */
340 if (of_find_property(node
, "hi6220,mbox-tx-noirq", NULL
))
341 mbox
->tx_irq_mode
= false;
343 mbox
->tx_irq_mode
= true;
345 if (mbox
->tx_irq_mode
)
346 mbox
->controller
.txdone_irq
= true;
348 mbox
->controller
.txdone_poll
= true;
349 mbox
->controller
.txpoll_period
= 5;
352 err
= devm_mbox_controller_register(dev
, &mbox
->controller
);
354 dev_err(dev
, "Failed to register mailbox %d\n", err
);
358 platform_set_drvdata(pdev
, mbox
);
359 dev_info(dev
, "Mailbox enabled\n");
363 static struct platform_driver hi6220_mbox_driver
= {
365 .name
= "hi6220-mbox",
366 .owner
= THIS_MODULE
,
367 .of_match_table
= hi6220_mbox_of_match
,
369 .probe
= hi6220_mbox_probe
,
372 static int __init
hi6220_mbox_init(void)
374 return platform_driver_register(&hi6220_mbox_driver
);
376 core_initcall(hi6220_mbox_init
);
378 static void __exit
hi6220_mbox_exit(void)
380 platform_driver_unregister(&hi6220_mbox_driver
);
382 module_exit(hi6220_mbox_exit
);
384 MODULE_AUTHOR("Leo Yan <leo.yan@linaro.org>");
385 MODULE_DESCRIPTION("Hi6220 mailbox driver");
386 MODULE_LICENSE("GPL v2");