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16#include <linux/types.h>
17#include <linux/err.h>
18#include <linux/delay.h>
19#include <linux/export.h>
20#include <linux/io.h>
21#include <linux/interrupt.h>
22#include <linux/completion.h>
23#include <linux/mutex.h>
24#include <linux/notifier.h>
25#include <linux/spinlock.h>
26#include <linux/device.h>
27#include <linux/amba/bus.h>
28
29#include <linux/pl320-ipc.h>
30
31#define IPCMxSOURCE(m) ((m) * 0x40)
32#define IPCMxDSET(m) (((m) * 0x40) + 0x004)
33#define IPCMxDCLEAR(m) (((m) * 0x40) + 0x008)
34#define IPCMxDSTATUS(m) (((m) * 0x40) + 0x00C)
35#define IPCMxMODE(m) (((m) * 0x40) + 0x010)
36#define IPCMxMSET(m) (((m) * 0x40) + 0x014)
37#define IPCMxMCLEAR(m) (((m) * 0x40) + 0x018)
38#define IPCMxMSTATUS(m) (((m) * 0x40) + 0x01C)
39#define IPCMxSEND(m) (((m) * 0x40) + 0x020)
40#define IPCMxDR(m, dr) (((m) * 0x40) + ((dr) * 4) + 0x024)
41
42#define IPCMMIS(irq) (((irq) * 8) + 0x800)
43#define IPCMRIS(irq) (((irq) * 8) + 0x804)
44
45#define MBOX_MASK(n) (1 << (n))
46#define IPC_TX_MBOX 1
47#define IPC_RX_MBOX 2
48
49#define CHAN_MASK(n) (1 << (n))
50#define A9_SOURCE 1
51#define M3_SOURCE 0
52
53static void __iomem *ipc_base;
54static int ipc_irq;
55static DEFINE_MUTEX(ipc_m1_lock);
56static DECLARE_COMPLETION(ipc_completion);
57static ATOMIC_NOTIFIER_HEAD(ipc_notifier);
58
59static inline void set_destination(int source, int mbox)
60{
61 writel_relaxed(CHAN_MASK(source), ipc_base + IPCMxDSET(mbox));
62 writel_relaxed(CHAN_MASK(source), ipc_base + IPCMxMSET(mbox));
63}
64
65static inline void clear_destination(int source, int mbox)
66{
67 writel_relaxed(CHAN_MASK(source), ipc_base + IPCMxDCLEAR(mbox));
68 writel_relaxed(CHAN_MASK(source), ipc_base + IPCMxMCLEAR(mbox));
69}
70
71static void __ipc_send(int mbox, u32 *data)
72{
73 int i;
74 for (i = 0; i < 7; i++)
75 writel_relaxed(data[i], ipc_base + IPCMxDR(mbox, i));
76 writel_relaxed(0x1, ipc_base + IPCMxSEND(mbox));
77}
78
79static u32 __ipc_rcv(int mbox, u32 *data)
80{
81 int i;
82 for (i = 0; i < 7; i++)
83 data[i] = readl_relaxed(ipc_base + IPCMxDR(mbox, i));
84 return data[1];
85}
86
87
88int pl320_ipc_transmit(u32 *data)
89{
90 int ret;
91
92 mutex_lock(&ipc_m1_lock);
93
94 init_completion(&ipc_completion);
95 __ipc_send(IPC_TX_MBOX, data);
96 ret = wait_for_completion_timeout(&ipc_completion,
97 msecs_to_jiffies(1000));
98 if (ret == 0) {
99 ret = -ETIMEDOUT;
100 goto out;
101 }
102
103 ret = __ipc_rcv(IPC_TX_MBOX, data);
104out:
105 mutex_unlock(&ipc_m1_lock);
106 return ret;
107}
108EXPORT_SYMBOL_GPL(pl320_ipc_transmit);
109
110static irqreturn_t ipc_handler(int irq, void *dev)
111{
112 u32 irq_stat;
113 u32 data[7];
114
115 irq_stat = readl_relaxed(ipc_base + IPCMMIS(1));
116 if (irq_stat & MBOX_MASK(IPC_TX_MBOX)) {
117 writel_relaxed(0, ipc_base + IPCMxSEND(IPC_TX_MBOX));
118 complete(&ipc_completion);
119 }
120 if (irq_stat & MBOX_MASK(IPC_RX_MBOX)) {
121 __ipc_rcv(IPC_RX_MBOX, data);
122 atomic_notifier_call_chain(&ipc_notifier, data[0], data + 1);
123 writel_relaxed(2, ipc_base + IPCMxSEND(IPC_RX_MBOX));
124 }
125
126 return IRQ_HANDLED;
127}
128
129int pl320_ipc_register_notifier(struct notifier_block *nb)
130{
131 return atomic_notifier_chain_register(&ipc_notifier, nb);
132}
133EXPORT_SYMBOL_GPL(pl320_ipc_register_notifier);
134
135int pl320_ipc_unregister_notifier(struct notifier_block *nb)
136{
137 return atomic_notifier_chain_unregister(&ipc_notifier, nb);
138}
139EXPORT_SYMBOL_GPL(pl320_ipc_unregister_notifier);
140
141static int pl320_probe(struct amba_device *adev, const struct amba_id *id)
142{
143 int ret;
144
145 ipc_base = ioremap(adev->res.start, resource_size(&adev->res));
146 if (ipc_base == NULL)
147 return -ENOMEM;
148
149 writel_relaxed(0, ipc_base + IPCMxSEND(IPC_TX_MBOX));
150
151 ipc_irq = adev->irq[0];
152 ret = request_irq(ipc_irq, ipc_handler, 0, dev_name(&adev->dev), NULL);
153 if (ret < 0)
154 goto err;
155
156
157 writel_relaxed(CHAN_MASK(A9_SOURCE),
158 ipc_base + IPCMxSOURCE(IPC_TX_MBOX));
159 writel_relaxed(CHAN_MASK(M3_SOURCE),
160 ipc_base + IPCMxDSET(IPC_TX_MBOX));
161 writel_relaxed(CHAN_MASK(M3_SOURCE) | CHAN_MASK(A9_SOURCE),
162 ipc_base + IPCMxMSET(IPC_TX_MBOX));
163
164
165 writel_relaxed(CHAN_MASK(M3_SOURCE),
166 ipc_base + IPCMxSOURCE(IPC_RX_MBOX));
167 writel_relaxed(CHAN_MASK(A9_SOURCE),
168 ipc_base + IPCMxDSET(IPC_RX_MBOX));
169 writel_relaxed(CHAN_MASK(M3_SOURCE) | CHAN_MASK(A9_SOURCE),
170 ipc_base + IPCMxMSET(IPC_RX_MBOX));
171
172 return 0;
173err:
174 iounmap(ipc_base);
175 return ret;
176}
177
178static struct amba_id pl320_ids[] = {
179 {
180 .id = 0x00041320,
181 .mask = 0x000fffff,
182 },
183 { 0, 0 },
184};
185
186static struct amba_driver pl320_driver = {
187 .drv = {
188 .name = "pl320",
189 },
190 .id_table = pl320_ids,
191 .probe = pl320_probe,
192};
193
194static int __init ipc_init(void)
195{
196 return amba_driver_register(&pl320_driver);
197}
198subsys_initcall(ipc_init);
199
