1 /*
2  * Copyright 2011-2012 Calxeda, Inc.
3  *
4  * This program is free software; you can redistribute it and/or modify it
5  * under the terms and conditions of the GNU General Public License,
6  * version 2, as published by the Free Software Foundation.
7  *
8  * This program is distributed in the hope it will be useful, but WITHOUT
9  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
10  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
11  * more details.
12  *
13  * You should have received a copy of the GNU General Public License along with
14  * this program.  If not, see <http://www.gnu.org/licenses/>.
15  */
16 #include <linux/types.h>
17 #include <linux/kernel.h>
18 #include <linux/ctype.h>
19 #include <linux/edac.h>
20 #include <linux/interrupt.h>
21 #include <linux/platform_device.h>
22 #include <linux/of_platform.h>
23 #include <linux/uaccess.h>
24 
25 #include "edac_module.h"
26 
27 /* DDR Ctrlr Error Registers */
28 
29 #define HB_DDR_ECC_ERR_BASE		0x128
30 #define MW_DDR_ECC_ERR_BASE		0x1b4
31 
32 #define HB_DDR_ECC_OPT			0x00
33 #define HB_DDR_ECC_U_ERR_ADDR		0x08
34 #define HB_DDR_ECC_U_ERR_STAT		0x0c
35 #define HB_DDR_ECC_U_ERR_DATAL		0x10
36 #define HB_DDR_ECC_U_ERR_DATAH		0x14
37 #define HB_DDR_ECC_C_ERR_ADDR		0x18
38 #define HB_DDR_ECC_C_ERR_STAT		0x1c
39 #define HB_DDR_ECC_C_ERR_DATAL		0x20
40 #define HB_DDR_ECC_C_ERR_DATAH		0x24
41 
42 #define HB_DDR_ECC_OPT_MODE_MASK	0x3
43 #define HB_DDR_ECC_OPT_FWC		0x100
44 #define HB_DDR_ECC_OPT_XOR_SHIFT	16
45 
46 /* DDR Ctrlr Interrupt Registers */
47 
48 #define HB_DDR_ECC_INT_BASE		0x180
49 #define MW_DDR_ECC_INT_BASE		0x218
50 
51 #define HB_DDR_ECC_INT_STATUS		0x00
52 #define HB_DDR_ECC_INT_ACK		0x04
53 
54 #define HB_DDR_ECC_INT_STAT_CE		0x8
55 #define HB_DDR_ECC_INT_STAT_DOUBLE_CE	0x10
56 #define HB_DDR_ECC_INT_STAT_UE		0x20
57 #define HB_DDR_ECC_INT_STAT_DOUBLE_UE	0x40
58 
59 struct hb_mc_drvdata {
60 	void __iomem *mc_err_base;
61 	void __iomem *mc_int_base;
62 };
63 
64 static irqreturn_t highbank_mc_err_handler(int irq, void *dev_id)
65 {
66 	struct mem_ctl_info *mci = dev_id;
67 	struct hb_mc_drvdata *drvdata = mci->pvt_info;
68 	u32 status, err_addr;
69 
70 	/* Read the interrupt status register */
71 	status = readl(drvdata->mc_int_base + HB_DDR_ECC_INT_STATUS);
72 
73 	if (status & HB_DDR_ECC_INT_STAT_UE) {
74 		err_addr = readl(drvdata->mc_err_base + HB_DDR_ECC_U_ERR_ADDR);
75 		edac_mc_handle_error(HW_EVENT_ERR_UNCORRECTED, mci, 1,
76 				     err_addr >> PAGE_SHIFT,
77 				     err_addr & ~PAGE_MASK, 0,
78 				     0, 0, -1,
79 				     mci->ctl_name, "");
80 	}
81 	if (status & HB_DDR_ECC_INT_STAT_CE) {
82 		u32 syndrome = readl(drvdata->mc_err_base + HB_DDR_ECC_C_ERR_STAT);
83 		syndrome = (syndrome >> 8) & 0xff;
84 		err_addr = readl(drvdata->mc_err_base + HB_DDR_ECC_C_ERR_ADDR);
85 		edac_mc_handle_error(HW_EVENT_ERR_CORRECTED, mci, 1,
86 				     err_addr >> PAGE_SHIFT,
87 				     err_addr & ~PAGE_MASK, syndrome,
88 				     0, 0, -1,
89 				     mci->ctl_name, "");
90 	}
91 
92 	/* clear the error, clears the interrupt */
93 	writel(status, drvdata->mc_int_base + HB_DDR_ECC_INT_ACK);
94 	return IRQ_HANDLED;
95 }
96 
97 static void highbank_mc_err_inject(struct mem_ctl_info *mci, u8 synd)
98 {
99 	struct hb_mc_drvdata *pdata = mci->pvt_info;
100 	u32 reg;
101 
102 	reg = readl(pdata->mc_err_base + HB_DDR_ECC_OPT);
103 	reg &= HB_DDR_ECC_OPT_MODE_MASK;
104 	reg |= (synd << HB_DDR_ECC_OPT_XOR_SHIFT) | HB_DDR_ECC_OPT_FWC;
105 	writel(reg, pdata->mc_err_base + HB_DDR_ECC_OPT);
106 }
107 
108 #define to_mci(k) container_of(k, struct mem_ctl_info, dev)
109 
110 static ssize_t highbank_mc_inject_ctrl(struct device *dev,
111 	struct device_attribute *attr, const char *buf, size_t count)
112 {
113 	struct mem_ctl_info *mci = to_mci(dev);
114 	u8 synd;
115 
116 	if (kstrtou8(buf, 16, &synd))
117 		return -EINVAL;
118 
119 	highbank_mc_err_inject(mci, synd);
120 
121 	return count;
122 }
123 
124 static DEVICE_ATTR(inject_ctrl, S_IWUSR, NULL, highbank_mc_inject_ctrl);
125 
126 static struct attribute *highbank_dev_attrs[] = {
127 	&dev_attr_inject_ctrl.attr,
128 	NULL
129 };
130 
131 ATTRIBUTE_GROUPS(highbank_dev);
132 
133 struct hb_mc_settings {
134 	int	err_offset;
135 	int	int_offset;
136 };
137 
138 static struct hb_mc_settings hb_settings = {
139 	.err_offset = HB_DDR_ECC_ERR_BASE,
140 	.int_offset = HB_DDR_ECC_INT_BASE,
141 };
142 
143 static struct hb_mc_settings mw_settings = {
144 	.err_offset = MW_DDR_ECC_ERR_BASE,
145 	.int_offset = MW_DDR_ECC_INT_BASE,
146 };
147 
148 static const struct of_device_id hb_ddr_ctrl_of_match[] = {
149 	{ .compatible = "calxeda,hb-ddr-ctrl",		.data = &hb_settings },
150 	{ .compatible = "calxeda,ecx-2000-ddr-ctrl",	.data = &mw_settings },
151 	{},
152 };
153 MODULE_DEVICE_TABLE(of, hb_ddr_ctrl_of_match);
154 
155 static int highbank_mc_probe(struct platform_device *pdev)
156 {
157 	const struct of_device_id *id;
158 	const struct hb_mc_settings *settings;
159 	struct edac_mc_layer layers[2];
160 	struct mem_ctl_info *mci;
161 	struct hb_mc_drvdata *drvdata;
162 	struct dimm_info *dimm;
163 	struct resource *r;
164 	void __iomem *base;
165 	u32 control;
166 	int irq;
167 	int res = 0;
168 
169 	id = of_match_device(hb_ddr_ctrl_of_match, &pdev->dev);
170 	if (!id)
171 		return -ENODEV;
172 
173 	layers[0].type = EDAC_MC_LAYER_CHIP_SELECT;
174 	layers[0].size = 1;
175 	layers[0].is_virt_csrow = true;
176 	layers[1].type = EDAC_MC_LAYER_CHANNEL;
177 	layers[1].size = 1;
178 	layers[1].is_virt_csrow = false;
179 	mci = edac_mc_alloc(0, ARRAY_SIZE(layers), layers,
180 			    sizeof(struct hb_mc_drvdata));
181 	if (!mci)
182 		return -ENOMEM;
183 
184 	mci->pdev = &pdev->dev;
185 	drvdata = mci->pvt_info;
186 	platform_set_drvdata(pdev, mci);
187 
188 	if (!devres_open_group(&pdev->dev, NULL, GFP_KERNEL))
189 		return -ENOMEM;
190 
191 	r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
192 	if (!r) {
193 		dev_err(&pdev->dev, "Unable to get mem resource\n");
194 		res = -ENODEV;
195 		goto err;
196 	}
197 
198 	if (!devm_request_mem_region(&pdev->dev, r->start,
199 				     resource_size(r), dev_name(&pdev->dev))) {
200 		dev_err(&pdev->dev, "Error while requesting mem region\n");
201 		res = -EBUSY;
202 		goto err;
203 	}
204 
205 	base = devm_ioremap(&pdev->dev, r->start, resource_size(r));
206 	if (!base) {
207 		dev_err(&pdev->dev, "Unable to map regs\n");
208 		res = -ENOMEM;
209 		goto err;
210 	}
211 
212 	settings = id->data;
213 	drvdata->mc_err_base = base + settings->err_offset;
214 	drvdata->mc_int_base = base + settings->int_offset;
215 
216 	control = readl(drvdata->mc_err_base + HB_DDR_ECC_OPT) & 0x3;
217 	if (!control || (control == 0x2)) {
218 		dev_err(&pdev->dev, "No ECC present, or ECC disabled\n");
219 		res = -ENODEV;
220 		goto err;
221 	}
222 
223 	mci->mtype_cap = MEM_FLAG_DDR3;
224 	mci->edac_ctl_cap = EDAC_FLAG_NONE | EDAC_FLAG_SECDED;
225 	mci->edac_cap = EDAC_FLAG_SECDED;
226 	mci->mod_name = pdev->dev.driver->name;
227 	mci->mod_ver = "1";
228 	mci->ctl_name = id->compatible;
229 	mci->dev_name = dev_name(&pdev->dev);
230 	mci->scrub_mode = SCRUB_SW_SRC;
231 
232 	/* Only a single 4GB DIMM is supported */
233 	dimm = *mci->dimms;
234 	dimm->nr_pages = (~0UL >> PAGE_SHIFT) + 1;
235 	dimm->grain = 8;
236 	dimm->dtype = DEV_X8;
237 	dimm->mtype = MEM_DDR3;
238 	dimm->edac_mode = EDAC_SECDED;
239 
240 	res = edac_mc_add_mc_with_groups(mci, highbank_dev_groups);
241 	if (res < 0)
242 		goto err;
243 
244 	irq = platform_get_irq(pdev, 0);
245 	res = devm_request_irq(&pdev->dev, irq, highbank_mc_err_handler,
246 			       0, dev_name(&pdev->dev), mci);
247 	if (res < 0) {
248 		dev_err(&pdev->dev, "Unable to request irq %d\n", irq);
249 		goto err2;
250 	}
251 
252 	devres_close_group(&pdev->dev, NULL);
253 	return 0;
254 err2:
255 	edac_mc_del_mc(&pdev->dev);
256 err:
257 	devres_release_group(&pdev->dev, NULL);
258 	edac_mc_free(mci);
259 	return res;
260 }
261 
262 static int highbank_mc_remove(struct platform_device *pdev)
263 {
264 	struct mem_ctl_info *mci = platform_get_drvdata(pdev);
265 
266 	edac_mc_del_mc(&pdev->dev);
267 	edac_mc_free(mci);
268 	return 0;
269 }
270 
271 static struct platform_driver highbank_mc_edac_driver = {
272 	.probe = highbank_mc_probe,
273 	.remove = highbank_mc_remove,
274 	.driver = {
275 		.name = "hb_mc_edac",
276 		.of_match_table = hb_ddr_ctrl_of_match,
277 	},
278 };
279 
280 module_platform_driver(highbank_mc_edac_driver);
281 
282 MODULE_LICENSE("GPL v2");
283 MODULE_AUTHOR("Calxeda, Inc.");
284 MODULE_DESCRIPTION("EDAC Driver for Calxeda Highbank");
285