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5
6#include <linux/clk.h>
7#include <linux/interrupt.h>
8#include <linux/io.h>
9#include <linux/kernel.h>
10#include <linux/mailbox_controller.h>
11#include <linux/module.h>
12#include <linux/of_device.h>
13#include <linux/platform_device.h>
14
15#define MAILBOX_A2B_INTEN 0x00
16#define MAILBOX_A2B_STATUS 0x04
17#define MAILBOX_A2B_CMD(x) (0x08 + (x) * 8)
18#define MAILBOX_A2B_DAT(x) (0x0c + (x) * 8)
19
20#define MAILBOX_B2A_INTEN 0x28
21#define MAILBOX_B2A_STATUS 0x2C
22#define MAILBOX_B2A_CMD(x) (0x30 + (x) * 8)
23#define MAILBOX_B2A_DAT(x) (0x34 + (x) * 8)
24
25struct rockchip_mbox_msg {
26 u32 cmd;
27 int rx_size;
28};
29
30struct rockchip_mbox_data {
31 int num_chans;
32};
33
34struct rockchip_mbox_chan {
35 int idx;
36 int irq;
37 struct rockchip_mbox_msg *msg;
38 struct rockchip_mbox *mb;
39};
40
41struct rockchip_mbox {
42 struct mbox_controller mbox;
43 struct clk *pclk;
44 void __iomem *mbox_base;
45
46
47 u32 buf_size;
48
49 struct rockchip_mbox_chan *chans;
50};
51
52static int rockchip_mbox_send_data(struct mbox_chan *chan, void *data)
53{
54 struct rockchip_mbox *mb = dev_get_drvdata(chan->mbox->dev);
55 struct rockchip_mbox_msg *msg = data;
56 struct rockchip_mbox_chan *chans = mb->chans;
57
58 if (!msg)
59 return -EINVAL;
60
61 if (msg->rx_size > mb->buf_size) {
62 dev_err(mb->mbox.dev, "Transmit size over buf size(%d)\n",
63 mb->buf_size);
64 return -EINVAL;
65 }
66
67 dev_dbg(mb->mbox.dev, "Chan[%d]: A2B message, cmd 0x%08x\n",
68 chans->idx, msg->cmd);
69
70 mb->chans[chans->idx].msg = msg;
71
72 writel_relaxed(msg->cmd, mb->mbox_base + MAILBOX_A2B_CMD(chans->idx));
73 writel_relaxed(msg->rx_size, mb->mbox_base +
74 MAILBOX_A2B_DAT(chans->idx));
75
76 return 0;
77}
78
79static int rockchip_mbox_startup(struct mbox_chan *chan)
80{
81 struct rockchip_mbox *mb = dev_get_drvdata(chan->mbox->dev);
82
83
84 writel_relaxed((1 << mb->mbox.num_chans) - 1,
85 mb->mbox_base + MAILBOX_B2A_INTEN);
86
87 return 0;
88}
89
90static void rockchip_mbox_shutdown(struct mbox_chan *chan)
91{
92 struct rockchip_mbox *mb = dev_get_drvdata(chan->mbox->dev);
93 struct rockchip_mbox_chan *chans = mb->chans;
94
95
96 writel_relaxed(0, mb->mbox_base + MAILBOX_B2A_INTEN);
97
98 mb->chans[chans->idx].msg = NULL;
99}
100
101static const struct mbox_chan_ops rockchip_mbox_chan_ops = {
102 .send_data = rockchip_mbox_send_data,
103 .startup = rockchip_mbox_startup,
104 .shutdown = rockchip_mbox_shutdown,
105};
106
107static irqreturn_t rockchip_mbox_irq(int irq, void *dev_id)
108{
109 int idx;
110 struct rockchip_mbox *mb = (struct rockchip_mbox *)dev_id;
111 u32 status = readl_relaxed(mb->mbox_base + MAILBOX_B2A_STATUS);
112
113 for (idx = 0; idx < mb->mbox.num_chans; idx++) {
114 if ((status & (1 << idx)) && (irq == mb->chans[idx].irq)) {
115
116 writel_relaxed(1 << idx,
117 mb->mbox_base + MAILBOX_B2A_STATUS);
118 return IRQ_WAKE_THREAD;
119 }
120 }
121
122 return IRQ_NONE;
123}
124
125static irqreturn_t rockchip_mbox_isr(int irq, void *dev_id)
126{
127 int idx;
128 struct rockchip_mbox_msg *msg = NULL;
129 struct rockchip_mbox *mb = (struct rockchip_mbox *)dev_id;
130
131 for (idx = 0; idx < mb->mbox.num_chans; idx++) {
132 if (irq != mb->chans[idx].irq)
133 continue;
134
135 msg = mb->chans[idx].msg;
136 if (!msg) {
137 dev_err(mb->mbox.dev,
138 "Chan[%d]: B2A message is NULL\n", idx);
139 break;
140 }
141
142 mbox_chan_received_data(&mb->mbox.chans[idx], msg);
143 mb->chans[idx].msg = NULL;
144
145 dev_dbg(mb->mbox.dev, "Chan[%d]: B2A message, cmd 0x%08x\n",
146 idx, msg->cmd);
147
148 break;
149 }
150
151 return IRQ_HANDLED;
152}
153
154static const struct rockchip_mbox_data rk3368_drv_data = {
155 .num_chans = 4,
156};
157
158static const struct of_device_id rockchip_mbox_of_match[] = {
159 { .compatible = "rockchip,rk3368-mailbox", .data = &rk3368_drv_data},
160 { },
161};
162MODULE_DEVICE_TABLE(of, rockchp_mbox_of_match);
163
164static int rockchip_mbox_probe(struct platform_device *pdev)
165{
166 struct rockchip_mbox *mb;
167 const struct of_device_id *match;
168 const struct rockchip_mbox_data *drv_data;
169 struct resource *res;
170 int ret, irq, i;
171
172 if (!pdev->dev.of_node)
173 return -ENODEV;
174
175 match = of_match_node(rockchip_mbox_of_match, pdev->dev.of_node);
176 drv_data = (const struct rockchip_mbox_data *)match->data;
177
178 mb = devm_kzalloc(&pdev->dev, sizeof(*mb), GFP_KERNEL);
179 if (!mb)
180 return -ENOMEM;
181
182 mb->chans = devm_kcalloc(&pdev->dev, drv_data->num_chans,
183 sizeof(*mb->chans), GFP_KERNEL);
184 if (!mb->chans)
185 return -ENOMEM;
186
187 mb->mbox.chans = devm_kcalloc(&pdev->dev, drv_data->num_chans,
188 sizeof(*mb->mbox.chans), GFP_KERNEL);
189 if (!mb->mbox.chans)
190 return -ENOMEM;
191
192 platform_set_drvdata(pdev, mb);
193
194 mb->mbox.dev = &pdev->dev;
195 mb->mbox.num_chans = drv_data->num_chans;
196 mb->mbox.ops = &rockchip_mbox_chan_ops;
197 mb->mbox.txdone_irq = true;
198
199 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
200 if (!res)
201 return -ENODEV;
202
203 mb->mbox_base = devm_ioremap_resource(&pdev->dev, res);
204 if (IS_ERR(mb->mbox_base))
205 return PTR_ERR(mb->mbox_base);
206
207
208 mb->buf_size = (size_t)resource_size(res) / (drv_data->num_chans * 2);
209
210 mb->pclk = devm_clk_get(&pdev->dev, "pclk_mailbox");
211 if (IS_ERR(mb->pclk)) {
212 ret = PTR_ERR(mb->pclk);
213 dev_err(&pdev->dev, "failed to get pclk_mailbox clock: %d\n",
214 ret);
215 return ret;
216 }
217
218 ret = clk_prepare_enable(mb->pclk);
219 if (ret) {
220 dev_err(&pdev->dev, "failed to enable pclk: %d\n", ret);
221 return ret;
222 }
223
224 for (i = 0; i < mb->mbox.num_chans; i++) {
225 irq = platform_get_irq(pdev, i);
226 if (irq < 0)
227 return irq;
228
229 ret = devm_request_threaded_irq(&pdev->dev, irq,
230 rockchip_mbox_irq,
231 rockchip_mbox_isr, IRQF_ONESHOT,
232 dev_name(&pdev->dev), mb);
233 if (ret < 0)
234 return ret;
235
236 mb->chans[i].idx = i;
237 mb->chans[i].irq = irq;
238 mb->chans[i].mb = mb;
239 mb->chans[i].msg = NULL;
240 }
241
242 ret = devm_mbox_controller_register(&pdev->dev, &mb->mbox);
243 if (ret < 0)
244 dev_err(&pdev->dev, "Failed to register mailbox: %d\n", ret);
245
246 return ret;
247}
248
249static struct platform_driver rockchip_mbox_driver = {
250 .probe = rockchip_mbox_probe,
251 .driver = {
252 .name = "rockchip-mailbox",
253 .of_match_table = of_match_ptr(rockchip_mbox_of_match),
254 },
255};
256
257module_platform_driver(rockchip_mbox_driver);
258
259MODULE_LICENSE("GPL v2");
260MODULE_DESCRIPTION("Rockchip mailbox: communicate between CPU cores and MCU");
261MODULE_AUTHOR("Addy Ke <addy.ke@rock-chips.com>");
262MODULE_AUTHOR("Caesar Wang <wxt@rock-chips.com>");
263
