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2
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4
5#include <linux/types.h>
6#include <linux/err.h>
7#include <linux/delay.h>
8#include <linux/export.h>
9#include <linux/io.h>
10#include <linux/interrupt.h>
11#include <linux/completion.h>
12#include <linux/mutex.h>
13#include <linux/notifier.h>
14#include <linux/spinlock.h>
15#include <linux/device.h>
16#include <linux/amba/bus.h>
17
18#include <linux/pl320-ipc.h>
19
20#define IPCMxSOURCE(m) ((m) * 0x40)
21#define IPCMxDSET(m) (((m) * 0x40) + 0x004)
22#define IPCMxDCLEAR(m) (((m) * 0x40) + 0x008)
23#define IPCMxDSTATUS(m) (((m) * 0x40) + 0x00C)
24#define IPCMxMODE(m) (((m) * 0x40) + 0x010)
25#define IPCMxMSET(m) (((m) * 0x40) + 0x014)
26#define IPCMxMCLEAR(m) (((m) * 0x40) + 0x018)
27#define IPCMxMSTATUS(m) (((m) * 0x40) + 0x01C)
28#define IPCMxSEND(m) (((m) * 0x40) + 0x020)
29#define IPCMxDR(m, dr) (((m) * 0x40) + ((dr) * 4) + 0x024)
30
31#define IPCMMIS(irq) (((irq) * 8) + 0x800)
32#define IPCMRIS(irq) (((irq) * 8) + 0x804)
33
34#define MBOX_MASK(n) (1 << (n))
35#define IPC_TX_MBOX 1
36#define IPC_RX_MBOX 2
37
38#define CHAN_MASK(n) (1 << (n))
39#define A9_SOURCE 1
40#define M3_SOURCE 0
41
42static void __iomem *ipc_base;
43static int ipc_irq;
44static DEFINE_MUTEX(ipc_m1_lock);
45static DECLARE_COMPLETION(ipc_completion);
46static ATOMIC_NOTIFIER_HEAD(ipc_notifier);
47
48static inline void set_destination(int source, int mbox)
49{
50 writel_relaxed(CHAN_MASK(source), ipc_base + IPCMxDSET(mbox));
51 writel_relaxed(CHAN_MASK(source), ipc_base + IPCMxMSET(mbox));
52}
53
54static inline void clear_destination(int source, int mbox)
55{
56 writel_relaxed(CHAN_MASK(source), ipc_base + IPCMxDCLEAR(mbox));
57 writel_relaxed(CHAN_MASK(source), ipc_base + IPCMxMCLEAR(mbox));
58}
59
60static void __ipc_send(int mbox, u32 *data)
61{
62 int i;
63 for (i = 0; i < 7; i++)
64 writel_relaxed(data[i], ipc_base + IPCMxDR(mbox, i));
65 writel_relaxed(0x1, ipc_base + IPCMxSEND(mbox));
66}
67
68static u32 __ipc_rcv(int mbox, u32 *data)
69{
70 int i;
71 for (i = 0; i < 7; i++)
72 data[i] = readl_relaxed(ipc_base + IPCMxDR(mbox, i));
73 return data[1];
74}
75
76
77int pl320_ipc_transmit(u32 *data)
78{
79 int ret;
80
81 mutex_lock(&ipc_m1_lock);
82
83 init_completion(&ipc_completion);
84 __ipc_send(IPC_TX_MBOX, data);
85 ret = wait_for_completion_timeout(&ipc_completion,
86 msecs_to_jiffies(1000));
87 if (ret == 0) {
88 ret = -ETIMEDOUT;
89 goto out;
90 }
91
92 ret = __ipc_rcv(IPC_TX_MBOX, data);
93out:
94 mutex_unlock(&ipc_m1_lock);
95 return ret;
96}
97EXPORT_SYMBOL_GPL(pl320_ipc_transmit);
98
99static irqreturn_t ipc_handler(int irq, void *dev)
100{
101 u32 irq_stat;
102 u32 data[7];
103
104 irq_stat = readl_relaxed(ipc_base + IPCMMIS(1));
105 if (irq_stat & MBOX_MASK(IPC_TX_MBOX)) {
106 writel_relaxed(0, ipc_base + IPCMxSEND(IPC_TX_MBOX));
107 complete(&ipc_completion);
108 }
109 if (irq_stat & MBOX_MASK(IPC_RX_MBOX)) {
110 __ipc_rcv(IPC_RX_MBOX, data);
111 atomic_notifier_call_chain(&ipc_notifier, data[0], data + 1);
112 writel_relaxed(2, ipc_base + IPCMxSEND(IPC_RX_MBOX));
113 }
114
115 return IRQ_HANDLED;
116}
117
118int pl320_ipc_register_notifier(struct notifier_block *nb)
119{
120 return atomic_notifier_chain_register(&ipc_notifier, nb);
121}
122EXPORT_SYMBOL_GPL(pl320_ipc_register_notifier);
123
124int pl320_ipc_unregister_notifier(struct notifier_block *nb)
125{
126 return atomic_notifier_chain_unregister(&ipc_notifier, nb);
127}
128EXPORT_SYMBOL_GPL(pl320_ipc_unregister_notifier);
129
130static int pl320_probe(struct amba_device *adev, const struct amba_id *id)
131{
132 int ret;
133
134 ipc_base = ioremap(adev->res.start, resource_size(&adev->res));
135 if (ipc_base == NULL)
136 return -ENOMEM;
137
138 writel_relaxed(0, ipc_base + IPCMxSEND(IPC_TX_MBOX));
139
140 ipc_irq = adev->irq[0];
141 ret = request_irq(ipc_irq, ipc_handler, 0, dev_name(&adev->dev), NULL);
142 if (ret < 0)
143 goto err;
144
145
146 writel_relaxed(CHAN_MASK(A9_SOURCE),
147 ipc_base + IPCMxSOURCE(IPC_TX_MBOX));
148 writel_relaxed(CHAN_MASK(M3_SOURCE),
149 ipc_base + IPCMxDSET(IPC_TX_MBOX));
150 writel_relaxed(CHAN_MASK(M3_SOURCE) | CHAN_MASK(A9_SOURCE),
151 ipc_base + IPCMxMSET(IPC_TX_MBOX));
152
153
154 writel_relaxed(CHAN_MASK(M3_SOURCE),
155 ipc_base + IPCMxSOURCE(IPC_RX_MBOX));
156 writel_relaxed(CHAN_MASK(A9_SOURCE),
157 ipc_base + IPCMxDSET(IPC_RX_MBOX));
158 writel_relaxed(CHAN_MASK(M3_SOURCE) | CHAN_MASK(A9_SOURCE),
159 ipc_base + IPCMxMSET(IPC_RX_MBOX));
160
161 return 0;
162err:
163 iounmap(ipc_base);
164 return ret;
165}
166
167static struct amba_id pl320_ids[] = {
168 {
169 .id = 0x00041320,
170 .mask = 0x000fffff,
171 },
172 { 0, 0 },
173};
174
175static struct amba_driver pl320_driver = {
176 .drv = {
177 .name = "pl320",
178 },
179 .id_table = pl320_ids,
180 .probe = pl320_probe,
181};
182
183static int __init ipc_init(void)
184{
185 return amba_driver_register(&pl320_driver);
186}
187subsys_initcall(ipc_init);
188
