1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
|
// SPDX-License-Identifier: GPL-2.0
//
// Copyright (c) 2019 MediaTek Inc.
#include <asm/barrier.h>
#include <linux/clk.h>
#include <linux/err.h>
#include <linux/io.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/remoteproc/mtk_scp.h>
#include "mtk_common.h"
/**
* scp_ipi_register() - register an ipi function
*
* @scp: mtk_scp structure
* @id: IPI ID
* @handler: IPI handler
* @priv: private data for IPI handler
*
* Register an ipi function to receive ipi interrupt from SCP.
*
* Return: 0 if ipi registers successfully, -error on error.
*/
int scp_ipi_register(struct mtk_scp *scp,
u32 id,
scp_ipi_handler_t handler,
void *priv)
{
if (!scp)
return -EPROBE_DEFER;
if (WARN_ON(id >= SCP_IPI_MAX) || WARN_ON(handler == NULL))
return -EINVAL;
scp_ipi_lock(scp, id);
scp->ipi_desc[id].handler = handler;
scp->ipi_desc[id].priv = priv;
scp_ipi_unlock(scp, id);
return 0;
}
EXPORT_SYMBOL_GPL(scp_ipi_register);
/**
* scp_ipi_unregister() - unregister an ipi function
*
* @scp: mtk_scp structure
* @id: IPI ID
*
* Unregister an ipi function to receive ipi interrupt from SCP.
*/
void scp_ipi_unregister(struct mtk_scp *scp, u32 id)
{
if (!scp)
return;
if (WARN_ON(id >= SCP_IPI_MAX))
return;
scp_ipi_lock(scp, id);
scp->ipi_desc[id].handler = NULL;
scp->ipi_desc[id].priv = NULL;
scp_ipi_unlock(scp, id);
}
EXPORT_SYMBOL_GPL(scp_ipi_unregister);
/*
* scp_memcpy_aligned() - Copy src to dst, where dst is in SCP SRAM region.
*
* @dst: Pointer to the destination buffer, should be in SCP SRAM region.
* @src: Pointer to the source buffer.
* @len: Length of the source buffer to be copied.
*
* Since AP access of SCP SRAM don't support byte write, this always write a
* full word at a time, and may cause some extra bytes to be written at the
* beginning & ending of dst.
*/
void scp_memcpy_aligned(void __iomem *dst, const void *src, unsigned int len)
{
void __iomem *ptr;
u32 val;
unsigned int i = 0, remain;
if (!IS_ALIGNED((unsigned long)dst, 4)) {
ptr = (void __iomem *)ALIGN_DOWN((unsigned long)dst, 4);
i = 4 - (dst - ptr);
val = readl_relaxed(ptr);
memcpy((u8 *)&val + (4 - i), src, i);
writel_relaxed(val, ptr);
}
__iowrite32_copy(dst + i, src + i, (len - i) / 4);
remain = (len - i) % 4;
if (remain > 0) {
val = readl_relaxed(dst + len - remain);
memcpy(&val, src + len - remain, remain);
writel_relaxed(val, dst + len - remain);
}
}
EXPORT_SYMBOL_GPL(scp_memcpy_aligned);
/**
* scp_ipi_lock() - Lock before operations of an IPI ID
*
* @scp: mtk_scp structure
* @id: IPI ID
*
* Note: This should not be used by drivers other than mtk_scp.
*/
void scp_ipi_lock(struct mtk_scp *scp, u32 id)
{
if (WARN_ON(id >= SCP_IPI_MAX))
return;
mutex_lock(&scp->ipi_desc[id].lock);
}
EXPORT_SYMBOL_GPL(scp_ipi_lock);
/**
* scp_ipi_lock() - Unlock after operations of an IPI ID
*
* @scp: mtk_scp structure
* @id: IPI ID
*
* Note: This should not be used by drivers other than mtk_scp.
*/
void scp_ipi_unlock(struct mtk_scp *scp, u32 id)
{
if (WARN_ON(id >= SCP_IPI_MAX))
return;
mutex_unlock(&scp->ipi_desc[id].lock);
}
EXPORT_SYMBOL_GPL(scp_ipi_unlock);
/**
* scp_ipi_send() - send data from AP to scp.
*
* @scp: mtk_scp structure
* @id: IPI ID
* @buf: the data buffer
* @len: the data buffer length
* @wait: number of msecs to wait for ack. 0 to skip waiting.
*
* This function is thread-safe. When this function returns,
* SCP has received the data and starts the processing.
* When the processing completes, IPI handler registered
* by scp_ipi_register will be called in interrupt context.
*
* Return: 0 if sending data successfully, -error on error.
**/
int scp_ipi_send(struct mtk_scp *scp, u32 id, void *buf, unsigned int len,
unsigned int wait)
{
struct mtk_share_obj __iomem *send_obj = scp->send_buf;
unsigned long timeout;
int ret;
if (WARN_ON(id <= SCP_IPI_INIT) || WARN_ON(id >= SCP_IPI_MAX) ||
WARN_ON(id == SCP_IPI_NS_SERVICE) ||
WARN_ON(len > sizeof(send_obj->share_buf)) || WARN_ON(!buf))
return -EINVAL;
mutex_lock(&scp->send_lock);
ret = clk_prepare_enable(scp->clk);
if (ret) {
dev_err(scp->dev, "failed to enable clock\n");
goto unlock_mutex;
}
/* Wait until SCP receives the last command */
timeout = jiffies + msecs_to_jiffies(2000);
do {
if (time_after(jiffies, timeout)) {
dev_err(scp->dev, "%s: IPI timeout!\n", __func__);
ret = -ETIMEDOUT;
goto clock_disable;
}
} while (readl(scp->reg_base + scp->data->host_to_scp_reg));
scp_memcpy_aligned(send_obj->share_buf, buf, len);
writel(len, &send_obj->len);
writel(id, &send_obj->id);
scp->ipi_id_ack[id] = false;
/* send the command to SCP */
writel(scp->data->host_to_scp_int_bit,
scp->reg_base + scp->data->host_to_scp_reg);
if (wait) {
/* wait for SCP's ACK */
timeout = msecs_to_jiffies(wait);
ret = wait_event_timeout(scp->ack_wq,
scp->ipi_id_ack[id],
timeout);
scp->ipi_id_ack[id] = false;
if (WARN(!ret, "scp ipi %d ack time out !", id))
ret = -EIO;
else
ret = 0;
}
clock_disable:
clk_disable_unprepare(scp->clk);
unlock_mutex:
mutex_unlock(&scp->send_lock);
return ret;
}
EXPORT_SYMBOL_GPL(scp_ipi_send);
MODULE_LICENSE("GPL v2");
MODULE_DESCRIPTION("MediaTek scp IPI interface");
|
