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8#include <linux/device.h>
9#include <linux/interrupt.h>
10#include <linux/io.h>
11#include <linux/kernel.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/armada-37xx-rwtm-mailbox.h>
17
18#define DRIVER_NAME "armada-37xx-rwtm-mailbox"
19
20
21#define RWTM_MBOX_PARAM(i) (0x0 + ((i) << 2))
22#define RWTM_MBOX_COMMAND 0x40
23#define RWTM_MBOX_RETURN_STATUS 0x80
24#define RWTM_MBOX_STATUS(i) (0x84 + ((i) << 2))
25#define RWTM_MBOX_FIFO_STATUS 0xc4
26#define FIFO_STS_RDY 0x100
27#define FIFO_STS_CNTR_MASK 0x7
28#define FIFO_STS_CNTR_MAX 4
29
30#define RWTM_HOST_INT_RESET 0xc8
31#define RWTM_HOST_INT_MASK 0xcc
32#define SP_CMD_COMPLETE BIT(0)
33#define SP_CMD_QUEUE_FULL_ACCESS BIT(17)
34#define SP_CMD_QUEUE_FULL BIT(18)
35
36struct a37xx_mbox {
37 struct device *dev;
38 struct mbox_controller controller;
39 void __iomem *base;
40 int irq;
41};
42
43static void a37xx_mbox_receive(struct mbox_chan *chan)
44{
45 struct a37xx_mbox *mbox = chan->con_priv;
46 struct armada_37xx_rwtm_rx_msg rx_msg;
47 int i;
48
49 rx_msg.retval = readl(mbox->base + RWTM_MBOX_RETURN_STATUS);
50 for (i = 0; i < 16; ++i)
51 rx_msg.status[i] = readl(mbox->base + RWTM_MBOX_STATUS(i));
52
53 mbox_chan_received_data(chan, &rx_msg);
54}
55
56static irqreturn_t a37xx_mbox_irq_handler(int irq, void *data)
57{
58 struct mbox_chan *chan = data;
59 struct a37xx_mbox *mbox = chan->con_priv;
60 u32 reg;
61
62 reg = readl(mbox->base + RWTM_HOST_INT_RESET);
63
64 if (reg & SP_CMD_COMPLETE)
65 a37xx_mbox_receive(chan);
66
67 if (reg & (SP_CMD_QUEUE_FULL_ACCESS | SP_CMD_QUEUE_FULL))
68 dev_err(mbox->dev, "Secure processor command queue full\n");
69
70 writel(reg, mbox->base + RWTM_HOST_INT_RESET);
71 if (reg)
72 mbox_chan_txdone(chan, 0);
73
74 return reg ? IRQ_HANDLED : IRQ_NONE;
75}
76
77static int a37xx_mbox_send_data(struct mbox_chan *chan, void *data)
78{
79 struct a37xx_mbox *mbox = chan->con_priv;
80 struct armada_37xx_rwtm_tx_msg *msg = data;
81 int i;
82 u32 reg;
83
84 if (!data)
85 return -EINVAL;
86
87 reg = readl(mbox->base + RWTM_MBOX_FIFO_STATUS);
88 if (!(reg & FIFO_STS_RDY))
89 dev_warn(mbox->dev, "Secure processor not ready\n");
90
91 if ((reg & FIFO_STS_CNTR_MASK) >= FIFO_STS_CNTR_MAX) {
92 dev_err(mbox->dev, "Secure processor command queue full\n");
93 return -EBUSY;
94 }
95
96 for (i = 0; i < 16; ++i)
97 writel(msg->args[i], mbox->base + RWTM_MBOX_PARAM(i));
98 writel(msg->command, mbox->base + RWTM_MBOX_COMMAND);
99
100 return 0;
101}
102
103static int a37xx_mbox_startup(struct mbox_chan *chan)
104{
105 struct a37xx_mbox *mbox = chan->con_priv;
106 u32 reg;
107 int ret;
108
109 ret = devm_request_irq(mbox->dev, mbox->irq, a37xx_mbox_irq_handler, 0,
110 DRIVER_NAME, chan);
111 if (ret < 0) {
112 dev_err(mbox->dev, "Cannot request irq\n");
113 return ret;
114 }
115
116
117 reg = readl(mbox->base + RWTM_HOST_INT_MASK);
118 reg &= ~(SP_CMD_COMPLETE | SP_CMD_QUEUE_FULL_ACCESS | SP_CMD_QUEUE_FULL);
119 writel(reg, mbox->base + RWTM_HOST_INT_MASK);
120
121 return 0;
122}
123
124static void a37xx_mbox_shutdown(struct mbox_chan *chan)
125{
126 u32 reg;
127 struct a37xx_mbox *mbox = chan->con_priv;
128
129
130 reg = readl(mbox->base + RWTM_HOST_INT_MASK);
131 reg |= SP_CMD_COMPLETE | SP_CMD_QUEUE_FULL_ACCESS | SP_CMD_QUEUE_FULL;
132 writel(reg, mbox->base + RWTM_HOST_INT_MASK);
133
134 devm_free_irq(mbox->dev, mbox->irq, chan);
135}
136
137static const struct mbox_chan_ops a37xx_mbox_ops = {
138 .send_data = a37xx_mbox_send_data,
139 .startup = a37xx_mbox_startup,
140 .shutdown = a37xx_mbox_shutdown,
141};
142
143static int armada_37xx_mbox_probe(struct platform_device *pdev)
144{
145 struct a37xx_mbox *mbox;
146 struct resource *regs;
147 struct mbox_chan *chans;
148 int ret;
149
150 mbox = devm_kzalloc(&pdev->dev, sizeof(*mbox), GFP_KERNEL);
151 if (!mbox)
152 return -ENOMEM;
153
154
155 chans = devm_kzalloc(&pdev->dev, sizeof(*chans), GFP_KERNEL);
156 if (!chans)
157 return -ENOMEM;
158
159 regs = platform_get_resource(pdev, IORESOURCE_MEM, 0);
160
161 mbox->base = devm_ioremap_resource(&pdev->dev, regs);
162 if (IS_ERR(mbox->base)) {
163 dev_err(&pdev->dev, "ioremap failed\n");
164 return PTR_ERR(mbox->base);
165 }
166
167 mbox->irq = platform_get_irq(pdev, 0);
168 if (mbox->irq < 0) {
169 dev_err(&pdev->dev, "Cannot get irq\n");
170 return mbox->irq;
171 }
172
173 mbox->dev = &pdev->dev;
174
175
176 chans[0].con_priv = mbox;
177 mbox->controller.dev = mbox->dev;
178 mbox->controller.num_chans = 1;
179 mbox->controller.chans = chans;
180 mbox->controller.ops = &a37xx_mbox_ops;
181 mbox->controller.txdone_irq = true;
182
183 ret = mbox_controller_register(&mbox->controller);
184 if (ret) {
185 dev_err(&pdev->dev, "Could not register mailbox controller\n");
186 return ret;
187 }
188
189 platform_set_drvdata(pdev, mbox);
190 return ret;
191}
192
193static int armada_37xx_mbox_remove(struct platform_device *pdev)
194{
195 struct a37xx_mbox *mbox = platform_get_drvdata(pdev);
196
197 if (!mbox)
198 return -EINVAL;
199
200 mbox_controller_unregister(&mbox->controller);
201
202 return 0;
203}
204
205static const struct of_device_id armada_37xx_mbox_match[] = {
206 { .compatible = "marvell,armada-3700-rwtm-mailbox" },
207 { },
208};
209
210MODULE_DEVICE_TABLE(of, armada_37xx_mbox_match);
211
212static struct platform_driver armada_37xx_mbox_driver = {
213 .probe = armada_37xx_mbox_probe,
214 .remove = armada_37xx_mbox_remove,
215 .driver = {
216 .name = DRIVER_NAME,
217 .of_match_table = armada_37xx_mbox_match,
218 },
219};
220
221module_platform_driver(armada_37xx_mbox_driver);
222
223MODULE_LICENSE("GPL v2");
224MODULE_DESCRIPTION("rWTM BIU Mailbox driver for Armada 37xx");
225MODULE_AUTHOR("Marek Behun <marek.behun@nic.cz>");
226
