summaryrefslogtreecommitdiff
path: root/drivers/fpga/altera-pr-ip-core.c
blob: df8671af4a92a066d621f696c8192b4c4ff2fa9a (plain)
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
// SPDX-License-Identifier: GPL-2.0
/*
 * Driver for Altera Partial Reconfiguration IP Core
 *
 * Copyright (C) 2016-2017 Intel Corporation
 *
 * Based on socfpga-a10.c Copyright (C) 2015-2016 Altera Corporation
 *  by Alan Tull <atull@opensource.altera.com>
 */
#include <linux/delay.h>
#include <linux/fpga/altera-pr-ip-core.h>
#include <linux/fpga/fpga-mgr.h>
#include <linux/module.h>

#define ALT_PR_DATA_OFST		0x00
#define ALT_PR_CSR_OFST			0x04

#define ALT_PR_CSR_PR_START		BIT(0)
#define ALT_PR_CSR_STATUS_SFT		2
#define ALT_PR_CSR_STATUS_MSK		(7 << ALT_PR_CSR_STATUS_SFT)
#define ALT_PR_CSR_STATUS_NRESET	(0 << ALT_PR_CSR_STATUS_SFT)
#define ALT_PR_CSR_STATUS_PR_ERR	(1 << ALT_PR_CSR_STATUS_SFT)
#define ALT_PR_CSR_STATUS_CRC_ERR	(2 << ALT_PR_CSR_STATUS_SFT)
#define ALT_PR_CSR_STATUS_BAD_BITS	(3 << ALT_PR_CSR_STATUS_SFT)
#define ALT_PR_CSR_STATUS_PR_IN_PROG	(4 << ALT_PR_CSR_STATUS_SFT)
#define ALT_PR_CSR_STATUS_PR_SUCCESS	(5 << ALT_PR_CSR_STATUS_SFT)

struct alt_pr_priv {
	void __iomem *reg_base;
};

static enum fpga_mgr_states alt_pr_fpga_state(struct fpga_manager *mgr)
{
	struct alt_pr_priv *priv = mgr->priv;
	const char *err = "unknown";
	enum fpga_mgr_states ret = FPGA_MGR_STATE_UNKNOWN;
	u32 val;

	val = readl(priv->reg_base + ALT_PR_CSR_OFST);

	val &= ALT_PR_CSR_STATUS_MSK;

	switch (val) {
	case ALT_PR_CSR_STATUS_NRESET:
		return FPGA_MGR_STATE_RESET;

	case ALT_PR_CSR_STATUS_PR_ERR:
		err = "pr error";
		ret = FPGA_MGR_STATE_WRITE_ERR;
		break;

	case ALT_PR_CSR_STATUS_CRC_ERR:
		err = "crc error";
		ret = FPGA_MGR_STATE_WRITE_ERR;
		break;

	case ALT_PR_CSR_STATUS_BAD_BITS:
		err = "bad bits";
		ret = FPGA_MGR_STATE_WRITE_ERR;
		break;

	case ALT_PR_CSR_STATUS_PR_IN_PROG:
		return FPGA_MGR_STATE_WRITE;

	case ALT_PR_CSR_STATUS_PR_SUCCESS:
		return FPGA_MGR_STATE_OPERATING;

	default:
		break;
	}

	dev_err(&mgr->dev, "encountered error code %d (%s) in %s()\n",
		val, err, __func__);
	return ret;
}

static int alt_pr_fpga_write_init(struct fpga_manager *mgr,
				  struct fpga_image_info *info,
				  const char *buf, size_t count)
{
	struct alt_pr_priv *priv = mgr->priv;
	u32 val;

	if (!(info->flags & FPGA_MGR_PARTIAL_RECONFIG)) {
		dev_err(&mgr->dev, "%s Partial Reconfiguration flag not set\n",
			__func__);
		return -EINVAL;
	}

	val = readl(priv->reg_base + ALT_PR_CSR_OFST);

	if (val & ALT_PR_CSR_PR_START) {
		dev_err(&mgr->dev,
			"%s Partial Reconfiguration already started\n",
		       __func__);
		return -EINVAL;
	}

	writel(val | ALT_PR_CSR_PR_START, priv->reg_base + ALT_PR_CSR_OFST);

	return 0;
}

static int alt_pr_fpga_write(struct fpga_manager *mgr, const char *buf,
			     size_t count)
{
	struct alt_pr_priv *priv = mgr->priv;
	u32 *buffer_32 = (u32 *)buf;
	size_t i = 0;

	if (!count)
		return -EINVAL;

	/* Write out the complete 32-bit chunks */
	while (count >= sizeof(u32)) {
		writel(buffer_32[i++], priv->reg_base);
		count -= sizeof(u32);
	}

	/* Write out remaining non 32-bit chunks */
	switch (count) {
	case 3:
		writel(buffer_32[i++] & 0x00ffffff, priv->reg_base);
		break;
	case 2:
		writel(buffer_32[i++] & 0x0000ffff, priv->reg_base);
		break;
	case 1:
		writel(buffer_32[i++] & 0x000000ff, priv->reg_base);
		break;
	case 0:
		break;
	default:
		/* This will never happen */
		return -EFAULT;
	}

	if (alt_pr_fpga_state(mgr) == FPGA_MGR_STATE_WRITE_ERR)
		return -EIO;

	return 0;
}

static int alt_pr_fpga_write_complete(struct fpga_manager *mgr,
				      struct fpga_image_info *info)
{
	u32 i = 0;

	do {
		switch (alt_pr_fpga_state(mgr)) {
		case FPGA_MGR_STATE_WRITE_ERR:
			return -EIO;

		case FPGA_MGR_STATE_OPERATING:
			dev_info(&mgr->dev,
				 "successful partial reconfiguration\n");
			return 0;

		default:
			break;
		}
		udelay(1);
	} while (info->config_complete_timeout_us > i++);

	dev_err(&mgr->dev, "timed out waiting for write to complete\n");
	return -ETIMEDOUT;
}

static const struct fpga_manager_ops alt_pr_ops = {
	.state = alt_pr_fpga_state,
	.write_init = alt_pr_fpga_write_init,
	.write = alt_pr_fpga_write,
	.write_complete = alt_pr_fpga_write_complete,
};

int alt_pr_register(struct device *dev, void __iomem *reg_base)
{
	struct alt_pr_priv *priv;
	struct fpga_manager *mgr;
	u32 val;

	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
	if (!priv)
		return -ENOMEM;

	priv->reg_base = reg_base;

	val = readl(priv->reg_base + ALT_PR_CSR_OFST);

	dev_dbg(dev, "%s status=%d start=%d\n", __func__,
		(val & ALT_PR_CSR_STATUS_MSK) >> ALT_PR_CSR_STATUS_SFT,
		(int)(val & ALT_PR_CSR_PR_START));

	mgr = devm_fpga_mgr_register(dev, dev_name(dev), &alt_pr_ops, priv);
	return PTR_ERR_OR_ZERO(mgr);
}
EXPORT_SYMBOL_GPL(alt_pr_register);

MODULE_AUTHOR("Matthew Gerlach <matthew.gerlach@linux.intel.com>");
MODULE_DESCRIPTION("Altera Partial Reconfiguration IP Core");
MODULE_LICENSE("GPL v2");