dfl-afu-error.c

  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. */
 31static void __afu_port_err_mask(struct dfl_feature_dev_data *fdata, bool mask)
 32{
 33	void __iomem *base;
 34
 35	base = dfl_get_feature_ioaddr_by_id(fdata, PORT_FEATURE_ID_ERROR);
 36
 37	writeq(mask ? ERROR_MASK : 0, base + PORT_ERROR_MASK);
 38}
 39
 40static void afu_port_err_mask(struct device *dev, bool mask)
 41{
 42	struct dfl_feature_dev_data *fdata = to_dfl_feature_dev_data(dev);
 43
 44	mutex_lock(&fdata->lock);
 45	__afu_port_err_mask(fdata, mask);
 46	mutex_unlock(&fdata->lock);
 47}
 48
 49/* clear port errors. */
 50static int afu_port_err_clear(struct device *dev, u64 err)
 51{
 52	struct dfl_feature_dev_data *fdata = to_dfl_feature_dev_data(dev);
 53	void __iomem *base_err, *base_hdr;
 54	int enable_ret = 0, ret = -EBUSY;
 55	u64 v;
 56
 57	base_err = dfl_get_feature_ioaddr_by_id(fdata, PORT_FEATURE_ID_ERROR);
 58	base_hdr = dfl_get_feature_ioaddr_by_id(fdata, PORT_FEATURE_ID_HEADER);
 59
 60	mutex_lock(&fdata->lock);
 61
 62	/*
 63	 * clear Port Errors
 64	 *
 65	 * - Check for AP6 State
 66	 * - Halt Port by keeping Port in reset
 67	 * - Set PORT Error mask to all 1 to mask errors
 68	 * - Clear all errors
 69	 * - Set Port mask to all 0 to enable errors
 70	 * - All errors start capturing new errors
 71	 * - Enable Port by pulling the port out of reset
 72	 */
 73
 74	/* if device is still in AP6 power state, can not clear any error. */
 75	v = readq(base_hdr + PORT_HDR_STS);
 76	if (FIELD_GET(PORT_STS_PWR_STATE, v) == PORT_STS_PWR_STATE_AP6) {
 77		dev_err(dev, "Could not clear errors, device in AP6 state.\n");
 78		goto done;
 79	}
 80
 81	/* Halt Port by keeping Port in reset */
 82	ret = __afu_port_disable(fdata);
 83	if (ret)
 84		goto done;
 85
 86	/* Mask all errors */
 87	__afu_port_err_mask(fdata, true);
 88
 89	/* Clear errors if err input matches with current port errors.*/
 90	v = readq(base_err + PORT_ERROR);
 91
 92	if (v == err) {
 93		writeq(v, base_err + PORT_ERROR);
 94
 95		v = readq(base_err + PORT_FIRST_ERROR);
 96		writeq(v, base_err + PORT_FIRST_ERROR);
 97	} else {
 98		dev_warn(dev, "%s: received 0x%llx, expected 0x%llx\n",
 99			 __func__, v, err);
100		ret = -EINVAL;
101	}
102
103	/* Clear mask */
104	__afu_port_err_mask(fdata, false);
105
106	/* Enable the Port by clearing the reset */
107	enable_ret = __afu_port_enable(fdata);
108
109done:
110	mutex_unlock(&fdata->lock);
111	return enable_ret ? enable_ret : ret;
112}
113
114static ssize_t errors_show(struct device *dev, struct device_attribute *attr,
115			   char *buf)
116{
117	struct dfl_feature_dev_data *fdata = to_dfl_feature_dev_data(dev);
118	void __iomem *base;
119	u64 error;
120
121	base = dfl_get_feature_ioaddr_by_id(fdata, PORT_FEATURE_ID_ERROR);
122
123	mutex_lock(&fdata->lock);
124	error = readq(base + PORT_ERROR);
125	mutex_unlock(&fdata->lock);
126
127	return sprintf(buf, "0x%llx\n", (unsigned long long)error);
128}
129
130static ssize_t errors_store(struct device *dev, struct device_attribute *attr,
131			    const char *buff, size_t count)
132{
133	u64 value;
134	int ret;
135
136	if (kstrtou64(buff, 0, &value))
137		return -EINVAL;
138
139	ret = afu_port_err_clear(dev, value);
140
141	return ret ? ret : count;
142}
143static DEVICE_ATTR_RW(errors);
144
145static ssize_t first_error_show(struct device *dev,
146				struct device_attribute *attr, char *buf)
147{
148	struct dfl_feature_dev_data *fdata = to_dfl_feature_dev_data(dev);
149	void __iomem *base;
150	u64 error;
151
152	base = dfl_get_feature_ioaddr_by_id(fdata, PORT_FEATURE_ID_ERROR);
153
154	mutex_lock(&fdata->lock);
155	error = readq(base + PORT_FIRST_ERROR);
156	mutex_unlock(&fdata->lock);
157
158	return sprintf(buf, "0x%llx\n", (unsigned long long)error);
159}
160static DEVICE_ATTR_RO(first_error);
161
162static ssize_t first_malformed_req_show(struct device *dev,
163					struct device_attribute *attr,
164					char *buf)
165{
166	struct dfl_feature_dev_data *fdata = to_dfl_feature_dev_data(dev);
167	void __iomem *base;
168	u64 req0, req1;
169
170	base = dfl_get_feature_ioaddr_by_id(fdata, PORT_FEATURE_ID_ERROR);
171
172	mutex_lock(&fdata->lock);
173	req0 = readq(base + PORT_MALFORMED_REQ0);
174	req1 = readq(base + PORT_MALFORMED_REQ1);
175	mutex_unlock(&fdata->lock);
176
177	return sprintf(buf, "0x%016llx%016llx\n",
178		       (unsigned long long)req1, (unsigned long long)req0);
179}
180static DEVICE_ATTR_RO(first_malformed_req);
181
182static struct attribute *port_err_attrs[] = {
183	&dev_attr_errors.attr,
184	&dev_attr_first_error.attr,
185	&dev_attr_first_malformed_req.attr,
186	NULL,
187};
188
189static umode_t port_err_attrs_visible(struct kobject *kobj,
190				      struct attribute *attr, int n)
191{
192	struct device *dev = kobj_to_dev(kobj);
193	struct dfl_feature_dev_data *fdata;
194
195	fdata = to_dfl_feature_dev_data(dev);
196	/*
197	 * sysfs entries are visible only if related private feature is
198	 * enumerated.
199	 */
200	if (!dfl_get_feature_by_id(fdata, PORT_FEATURE_ID_ERROR))
201		return 0;
202
203	return attr->mode;
204}
205
206const struct attribute_group port_err_group = {
207	.name       = "errors",
208	.attrs      = port_err_attrs,
209	.is_visible = port_err_attrs_visible,
210};
211
212static int port_err_init(struct platform_device *pdev,
213			 struct dfl_feature *feature)
214{
215	afu_port_err_mask(&pdev->dev, false);
216
217	return 0;
218}
219
220static void port_err_uinit(struct platform_device *pdev,
221			   struct dfl_feature *feature)
222{
223	afu_port_err_mask(&pdev->dev, true);
224}
225
226static long
227port_err_ioctl(struct platform_device *pdev, struct dfl_feature *feature,
228	       unsigned int cmd, unsigned long arg)
229{
230	switch (cmd) {
231	case DFL_FPGA_PORT_ERR_GET_IRQ_NUM:
232		return dfl_feature_ioctl_get_num_irqs(pdev, feature, arg);
233	case DFL_FPGA_PORT_ERR_SET_IRQ:
234		return dfl_feature_ioctl_set_irq(pdev, feature, arg);
235	default:
236		dev_dbg(&pdev->dev, "%x cmd not handled", cmd);
237		return -ENODEV;
238	}
239}
240
241const struct dfl_feature_id port_err_id_table[] = {
242	{.id = PORT_FEATURE_ID_ERROR,},
243	{0,}
244};
245
246const struct dfl_feature_ops port_err_ops = {
247	.init = port_err_init,
248	.uinit = port_err_uinit,
249	.ioctl = port_err_ioctl,
250};