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8#include <linux/acpi.h>
9#include <linux/delay.h>
10#include <linux/interrupt.h>
11#include <linux/io.h>
12#include <linux/mailbox_controller.h>
13#include <linux/module.h>
14#include <linux/of.h>
15#include <linux/platform_device.h>
16#include <linux/spinlock.h>
17
18#define MBOX_CON_NAME "slimpro-mbox"
19#define MBOX_REG_SET_OFFSET 0x1000
20#define MBOX_CNT 8
21#define MBOX_STATUS_AVAIL_MASK BIT(16)
22#define MBOX_STATUS_ACK_MASK BIT(0)
23
24
25#define REG_DB_IN 0x00
26#define REG_DB_DIN0 0x04
27#define REG_DB_DIN1 0x08
28#define REG_DB_OUT 0x10
29#define REG_DB_DOUT0 0x14
30#define REG_DB_DOUT1 0x18
31#define REG_DB_STAT 0x20
32#define REG_DB_STATMASK 0x24
33
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41
42
43struct slimpro_mbox_chan {
44 struct device *dev;
45 struct mbox_chan *chan;
46 void __iomem *reg;
47 int irq;
48 u32 rx_msg[3];
49};
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60
61
62struct slimpro_mbox {
63 struct mbox_controller mb_ctrl;
64 struct slimpro_mbox_chan mc[MBOX_CNT];
65 struct mbox_chan chans[MBOX_CNT];
66};
67
68static void mb_chan_send_msg(struct slimpro_mbox_chan *mb_chan, u32 *msg)
69{
70 writel(msg[1], mb_chan->reg + REG_DB_DOUT0);
71 writel(msg[2], mb_chan->reg + REG_DB_DOUT1);
72 writel(msg[0], mb_chan->reg + REG_DB_OUT);
73}
74
75static void mb_chan_recv_msg(struct slimpro_mbox_chan *mb_chan)
76{
77 mb_chan->rx_msg[1] = readl(mb_chan->reg + REG_DB_DIN0);
78 mb_chan->rx_msg[2] = readl(mb_chan->reg + REG_DB_DIN1);
79 mb_chan->rx_msg[0] = readl(mb_chan->reg + REG_DB_IN);
80}
81
82static int mb_chan_status_ack(struct slimpro_mbox_chan *mb_chan)
83{
84 u32 val = readl(mb_chan->reg + REG_DB_STAT);
85
86 if (val & MBOX_STATUS_ACK_MASK) {
87 writel(MBOX_STATUS_ACK_MASK, mb_chan->reg + REG_DB_STAT);
88 return 1;
89 }
90 return 0;
91}
92
93static int mb_chan_status_avail(struct slimpro_mbox_chan *mb_chan)
94{
95 u32 val = readl(mb_chan->reg + REG_DB_STAT);
96
97 if (val & MBOX_STATUS_AVAIL_MASK) {
98 mb_chan_recv_msg(mb_chan);
99 writel(MBOX_STATUS_AVAIL_MASK, mb_chan->reg + REG_DB_STAT);
100 return 1;
101 }
102 return 0;
103}
104
105static irqreturn_t slimpro_mbox_irq(int irq, void *id)
106{
107 struct slimpro_mbox_chan *mb_chan = id;
108
109 if (mb_chan_status_ack(mb_chan))
110 mbox_chan_txdone(mb_chan->chan, 0);
111
112 if (mb_chan_status_avail(mb_chan))
113 mbox_chan_received_data(mb_chan->chan, mb_chan->rx_msg);
114
115 return IRQ_HANDLED;
116}
117
118static int slimpro_mbox_send_data(struct mbox_chan *chan, void *msg)
119{
120 struct slimpro_mbox_chan *mb_chan = chan->con_priv;
121
122 mb_chan_send_msg(mb_chan, msg);
123 return 0;
124}
125
126static int slimpro_mbox_startup(struct mbox_chan *chan)
127{
128 struct slimpro_mbox_chan *mb_chan = chan->con_priv;
129 int rc;
130 u32 val;
131
132 rc = devm_request_irq(mb_chan->dev, mb_chan->irq, slimpro_mbox_irq, 0,
133 MBOX_CON_NAME, mb_chan);
134 if (unlikely(rc)) {
135 dev_err(mb_chan->dev, "failed to register mailbox interrupt %d\n",
136 mb_chan->irq);
137 return rc;
138 }
139
140
141 writel(MBOX_STATUS_ACK_MASK | MBOX_STATUS_AVAIL_MASK,
142 mb_chan->reg + REG_DB_STAT);
143
144 val = readl(mb_chan->reg + REG_DB_STATMASK);
145 val &= ~(MBOX_STATUS_ACK_MASK | MBOX_STATUS_AVAIL_MASK);
146 writel(val, mb_chan->reg + REG_DB_STATMASK);
147
148 return 0;
149}
150
151static void slimpro_mbox_shutdown(struct mbox_chan *chan)
152{
153 struct slimpro_mbox_chan *mb_chan = chan->con_priv;
154 u32 val;
155
156
157 val = readl(mb_chan->reg + REG_DB_STATMASK);
158 val |= (MBOX_STATUS_ACK_MASK | MBOX_STATUS_AVAIL_MASK);
159 writel(val, mb_chan->reg + REG_DB_STATMASK);
160
161 devm_free_irq(mb_chan->dev, mb_chan->irq, mb_chan);
162}
163
164static const struct mbox_chan_ops slimpro_mbox_ops = {
165 .send_data = slimpro_mbox_send_data,
166 .startup = slimpro_mbox_startup,
167 .shutdown = slimpro_mbox_shutdown,
168};
169
170static int slimpro_mbox_probe(struct platform_device *pdev)
171{
172 struct slimpro_mbox *ctx;
173 struct resource *regs;
174 void __iomem *mb_base;
175 int rc;
176 int i;
177
178 ctx = devm_kzalloc(&pdev->dev, sizeof(struct slimpro_mbox), GFP_KERNEL);
179 if (!ctx)
180 return -ENOMEM;
181
182 platform_set_drvdata(pdev, ctx);
183
184 regs = platform_get_resource(pdev, IORESOURCE_MEM, 0);
185 mb_base = devm_ioremap_resource(&pdev->dev, regs);
186 if (IS_ERR(mb_base))
187 return PTR_ERR(mb_base);
188
189
190 for (i = 0; i < MBOX_CNT; i++) {
191 ctx->mc[i].irq = platform_get_irq(pdev, i);
192 if (ctx->mc[i].irq < 0) {
193 if (i == 0) {
194 dev_err(&pdev->dev, "no available IRQ\n");
195 return -EINVAL;
196 }
197 dev_info(&pdev->dev, "no IRQ for channel %d\n", i);
198 break;
199 }
200
201 ctx->mc[i].dev = &pdev->dev;
202 ctx->mc[i].reg = mb_base + i * MBOX_REG_SET_OFFSET;
203 ctx->mc[i].chan = &ctx->chans[i];
204 ctx->chans[i].con_priv = &ctx->mc[i];
205 }
206
207
208 ctx->mb_ctrl.dev = &pdev->dev;
209 ctx->mb_ctrl.chans = ctx->chans;
210 ctx->mb_ctrl.txdone_irq = true;
211 ctx->mb_ctrl.ops = &slimpro_mbox_ops;
212 ctx->mb_ctrl.num_chans = i;
213
214 rc = devm_mbox_controller_register(&pdev->dev, &ctx->mb_ctrl);
215 if (rc) {
216 dev_err(&pdev->dev,
217 "APM X-Gene SLIMpro MailBox register failed:%d\n", rc);
218 return rc;
219 }
220
221 dev_info(&pdev->dev, "APM X-Gene SLIMpro MailBox registered\n");
222 return 0;
223}
224
225static const struct of_device_id slimpro_of_match[] = {
226 {.compatible = "apm,xgene-slimpro-mbox" },
227 { },
228};
229MODULE_DEVICE_TABLE(of, slimpro_of_match);
230
231#ifdef CONFIG_ACPI
232static const struct acpi_device_id slimpro_acpi_ids[] = {
233 {"APMC0D01", 0},
234 {}
235};
236MODULE_DEVICE_TABLE(acpi, slimpro_acpi_ids);
237#endif
238
239static struct platform_driver slimpro_mbox_driver = {
240 .probe = slimpro_mbox_probe,
241 .driver = {
242 .name = "xgene-slimpro-mbox",
243 .of_match_table = of_match_ptr(slimpro_of_match),
244 .acpi_match_table = ACPI_PTR(slimpro_acpi_ids)
245 },
246};
247
248static int __init slimpro_mbox_init(void)
249{
250 return platform_driver_register(&slimpro_mbox_driver);
251}
252
253static void __exit slimpro_mbox_exit(void)
254{
255 platform_driver_unregister(&slimpro_mbox_driver);
256}
257
258subsys_initcall(slimpro_mbox_init);
259module_exit(slimpro_mbox_exit);
260
261MODULE_DESCRIPTION("APM X-Gene SLIMpro Mailbox Driver");
262MODULE_LICENSE("GPL");
263
