xref: /linux/drivers/fpga/dfl-afu-error.c (revision 8137a49e1567726eb10fcf55ad141ac19804ca6b)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Driver for FPGA Accelerated Function Unit (AFU) Error Reporting
4  *
5  * Copyright 2019 Intel Corporation, Inc.
6  *
7  * Authors:
8  *   Wu Hao <hao.wu@linux.intel.com>
9  *   Xiao Guangrong <guangrong.xiao@linux.intel.com>
10  *   Joseph Grecco <joe.grecco@intel.com>
11  *   Enno Luebbers <enno.luebbers@intel.com>
12  *   Tim Whisonant <tim.whisonant@intel.com>
13  *   Ananda Ravuri <ananda.ravuri@intel.com>
14  *   Mitchel Henry <henry.mitchel@intel.com>
15  */
16 
17 #include <linux/fpga-dfl.h>
18 #include <linux/uaccess.h>
19 
20 #include "dfl-afu.h"
21 
22 #define PORT_ERROR_MASK		0x8
23 #define PORT_ERROR		0x10
24 #define PORT_FIRST_ERROR	0x18
25 #define PORT_MALFORMED_REQ0	0x20
26 #define PORT_MALFORMED_REQ1	0x28
27 
28 #define ERROR_MASK		GENMASK_ULL(63, 0)
29 
30 /* mask or unmask port errors by the error mask register. */
31 static void __afu_port_err_mask(struct device *dev, bool mask)
32 {
33 	void __iomem *base;
34 
35 	base = dfl_get_feature_ioaddr_by_id(dev, PORT_FEATURE_ID_ERROR);
36 
37 	writeq(mask ? ERROR_MASK : 0, base + PORT_ERROR_MASK);
38 }
39 
40 static void afu_port_err_mask(struct device *dev, bool mask)
41 {
42 	struct dfl_feature_platform_data *pdata = dev_get_platdata(dev);
43 
44 	mutex_lock(&pdata->lock);
45 	__afu_port_err_mask(dev, mask);
46 	mutex_unlock(&pdata->lock);
47 }
48 
49 /* clear port errors. */
50 static int afu_port_err_clear(struct device *dev, u64 err)
51 {
52 	struct dfl_feature_platform_data *pdata = dev_get_platdata(dev);
53 	struct platform_device *pdev = to_platform_device(dev);
54 	void __iomem *base_err, *base_hdr;
55 	int enable_ret = 0, ret = -EBUSY;
56 	u64 v;
57 
58 	base_err = dfl_get_feature_ioaddr_by_id(dev, PORT_FEATURE_ID_ERROR);
59 	base_hdr = dfl_get_feature_ioaddr_by_id(dev, PORT_FEATURE_ID_HEADER);
60 
61 	mutex_lock(&pdata->lock);
62 
63 	/*
64 	 * clear Port Errors
65 	 *
66 	 * - Check for AP6 State
67 	 * - Halt Port by keeping Port in reset
68 	 * - Set PORT Error mask to all 1 to mask errors
69 	 * - Clear all errors
70 	 * - Set Port mask to all 0 to enable errors
71 	 * - All errors start capturing new errors
72 	 * - Enable Port by pulling the port out of reset
73 	 */
74 
75 	/* if device is still in AP6 power state, can not clear any error. */
76 	v = readq(base_hdr + PORT_HDR_STS);
77 	if (FIELD_GET(PORT_STS_PWR_STATE, v) == PORT_STS_PWR_STATE_AP6) {
78 		dev_err(dev, "Could not clear errors, device in AP6 state.\n");
79 		goto done;
80 	}
81 
82 	/* Halt Port by keeping Port in reset */
83 	ret = __afu_port_disable(pdev);
84 	if (ret)
85 		goto done;
86 
87 	/* Mask all errors */
88 	__afu_port_err_mask(dev, true);
89 
90 	/* Clear errors if err input matches with current port errors.*/
91 	v = readq(base_err + PORT_ERROR);
92 
93 	if (v == err) {
94 		writeq(v, base_err + PORT_ERROR);
95 
96 		v = readq(base_err + PORT_FIRST_ERROR);
97 		writeq(v, base_err + PORT_FIRST_ERROR);
98 	} else {
99 		dev_warn(dev, "%s: received 0x%llx, expected 0x%llx\n",
100 			 __func__, v, err);
101 		ret = -EINVAL;
102 	}
103 
104 	/* Clear mask */
105 	__afu_port_err_mask(dev, false);
106 
107 	/* Enable the Port by clearing the reset */
108 	enable_ret = __afu_port_enable(pdev);
109 
110 done:
111 	mutex_unlock(&pdata->lock);
112 	return enable_ret ? enable_ret : ret;
113 }
114 
115 static ssize_t errors_show(struct device *dev, struct device_attribute *attr,
116 			   char *buf)
117 {
118 	struct dfl_feature_platform_data *pdata = dev_get_platdata(dev);
119 	void __iomem *base;
120 	u64 error;
121 
122 	base = dfl_get_feature_ioaddr_by_id(dev, PORT_FEATURE_ID_ERROR);
123 
124 	mutex_lock(&pdata->lock);
125 	error = readq(base + PORT_ERROR);
126 	mutex_unlock(&pdata->lock);
127 
128 	return sprintf(buf, "0x%llx\n", (unsigned long long)error);
129 }
130 
131 static ssize_t errors_store(struct device *dev, struct device_attribute *attr,
132 			    const char *buff, size_t count)
133 {
134 	u64 value;
135 	int ret;
136 
137 	if (kstrtou64(buff, 0, &value))
138 		return -EINVAL;
139 
140 	ret = afu_port_err_clear(dev, value);
141 
142 	return ret ? ret : count;
143 }
144 static DEVICE_ATTR_RW(errors);
145 
146 static ssize_t first_error_show(struct device *dev,
147 				struct device_attribute *attr, char *buf)
148 {
149 	struct dfl_feature_platform_data *pdata = dev_get_platdata(dev);
150 	void __iomem *base;
151 	u64 error;
152 
153 	base = dfl_get_feature_ioaddr_by_id(dev, PORT_FEATURE_ID_ERROR);
154 
155 	mutex_lock(&pdata->lock);
156 	error = readq(base + PORT_FIRST_ERROR);
157 	mutex_unlock(&pdata->lock);
158 
159 	return sprintf(buf, "0x%llx\n", (unsigned long long)error);
160 }
161 static DEVICE_ATTR_RO(first_error);
162 
163 static ssize_t first_malformed_req_show(struct device *dev,
164 					struct device_attribute *attr,
165 					char *buf)
166 {
167 	struct dfl_feature_platform_data *pdata = dev_get_platdata(dev);
168 	void __iomem *base;
169 	u64 req0, req1;
170 
171 	base = dfl_get_feature_ioaddr_by_id(dev, PORT_FEATURE_ID_ERROR);
172 
173 	mutex_lock(&pdata->lock);
174 	req0 = readq(base + PORT_MALFORMED_REQ0);
175 	req1 = readq(base + PORT_MALFORMED_REQ1);
176 	mutex_unlock(&pdata->lock);
177 
178 	return sprintf(buf, "0x%016llx%016llx\n",
179 		       (unsigned long long)req1, (unsigned long long)req0);
180 }
181 static DEVICE_ATTR_RO(first_malformed_req);
182 
183 static struct attribute *port_err_attrs[] = {
184 	&dev_attr_errors.attr,
185 	&dev_attr_first_error.attr,
186 	&dev_attr_first_malformed_req.attr,
187 	NULL,
188 };
189 
190 static umode_t port_err_attrs_visible(struct kobject *kobj,
191 				      struct attribute *attr, int n)
192 {
193 	struct device *dev = kobj_to_dev(kobj);
194 
195 	/*
196 	 * sysfs entries are visible only if related private feature is
197 	 * enumerated.
198 	 */
199 	if (!dfl_get_feature_by_id(dev, PORT_FEATURE_ID_ERROR))
200 		return 0;
201 
202 	return attr->mode;
203 }
204 
205 const struct attribute_group port_err_group = {
206 	.name       = "errors",
207 	.attrs      = port_err_attrs,
208 	.is_visible = port_err_attrs_visible,
209 };
210 
211 static int port_err_init(struct platform_device *pdev,
212 			 struct dfl_feature *feature)
213 {
214 	afu_port_err_mask(&pdev->dev, false);
215 
216 	return 0;
217 }
218 
219 static void port_err_uinit(struct platform_device *pdev,
220 			   struct dfl_feature *feature)
221 {
222 	afu_port_err_mask(&pdev->dev, true);
223 }
224 
225 static long
226 port_err_ioctl(struct platform_device *pdev, struct dfl_feature *feature,
227 	       unsigned int cmd, unsigned long arg)
228 {
229 	switch (cmd) {
230 	case DFL_FPGA_PORT_ERR_GET_IRQ_NUM:
231 		return dfl_feature_ioctl_get_num_irqs(pdev, feature, arg);
232 	case DFL_FPGA_PORT_ERR_SET_IRQ:
233 		return dfl_feature_ioctl_set_irq(pdev, feature, arg);
234 	default:
235 		dev_dbg(&pdev->dev, "%x cmd not handled", cmd);
236 		return -ENODEV;
237 	}
238 }
239 
240 const struct dfl_feature_id port_err_id_table[] = {
241 	{.id = PORT_FEATURE_ID_ERROR,},
242 	{0,}
243 };
244 
245 const struct dfl_feature_ops port_err_ops = {
246 	.init = port_err_init,
247 	.uinit = port_err_uinit,
248 	.ioctl = port_err_ioctl,
249 };
250