xref: /openbmc/linux/drivers/edac/cell_edac.c (revision ab73b751)
1 /*
2  * Cell MIC driver for ECC counting
3  *
4  * Copyright 2007 Benjamin Herrenschmidt, IBM Corp.
5  *                <benh@kernel.crashing.org>
6  *
7  * This file may be distributed under the terms of the
8  * GNU General Public License.
9  */
10 #undef DEBUG
11 
12 #include <linux/edac.h>
13 #include <linux/module.h>
14 #include <linux/init.h>
15 #include <linux/platform_device.h>
16 #include <linux/stop_machine.h>
17 #include <linux/io.h>
18 #include <asm/machdep.h>
19 #include <asm/cell-regs.h>
20 
21 #include "edac_core.h"
22 
23 struct cell_edac_priv
24 {
25 	struct cbe_mic_tm_regs __iomem	*regs;
26 	int				node;
27 	int				chanmask;
28 #ifdef DEBUG
29 	u64				prev_fir;
30 #endif
31 };
32 
33 static void cell_edac_count_ce(struct mem_ctl_info *mci, int chan, u64 ar)
34 {
35 	struct cell_edac_priv		*priv = mci->pvt_info;
36 	struct csrow_info		*csrow = &mci->csrows[0];
37 	unsigned long			address, pfn, offset, syndrome;
38 
39 	dev_dbg(mci->dev, "ECC CE err on node %d, channel %d, ar = 0x%016llx\n",
40 		priv->node, chan, ar);
41 
42 	/* Address decoding is likely a bit bogus, to dbl check */
43 	address = (ar & 0xffffffffe0000000ul) >> 29;
44 	if (priv->chanmask == 0x3)
45 		address = (address << 1) | chan;
46 	pfn = address >> PAGE_SHIFT;
47 	offset = address & ~PAGE_MASK;
48 	syndrome = (ar & 0x000000001fe00000ul) >> 21;
49 
50 	/* TODO: Decoding of the error address */
51 	edac_mc_handle_error(HW_EVENT_ERR_CORRECTED, mci,
52 			     csrow->first_page + pfn, offset, syndrome,
53 			     0, chan, -1, "", "", NULL);
54 }
55 
56 static void cell_edac_count_ue(struct mem_ctl_info *mci, int chan, u64 ar)
57 {
58 	struct cell_edac_priv		*priv = mci->pvt_info;
59 	struct csrow_info		*csrow = &mci->csrows[0];
60 	unsigned long			address, pfn, offset;
61 
62 	dev_dbg(mci->dev, "ECC UE err on node %d, channel %d, ar = 0x%016llx\n",
63 		priv->node, chan, ar);
64 
65 	/* Address decoding is likely a bit bogus, to dbl check */
66 	address = (ar & 0xffffffffe0000000ul) >> 29;
67 	if (priv->chanmask == 0x3)
68 		address = (address << 1) | chan;
69 	pfn = address >> PAGE_SHIFT;
70 	offset = address & ~PAGE_MASK;
71 
72 	/* TODO: Decoding of the error address */
73 	edac_mc_handle_error(HW_EVENT_ERR_UNCORRECTED, mci,
74 			     csrow->first_page + pfn, offset, 0,
75 			     0, chan, -1, "", "", NULL);
76 }
77 
78 static void cell_edac_check(struct mem_ctl_info *mci)
79 {
80 	struct cell_edac_priv		*priv = mci->pvt_info;
81 	u64				fir, addreg, clear = 0;
82 
83 	fir = in_be64(&priv->regs->mic_fir);
84 #ifdef DEBUG
85 	if (fir != priv->prev_fir) {
86 		dev_dbg(mci->dev, "fir change : 0x%016lx\n", fir);
87 		priv->prev_fir = fir;
88 	}
89 #endif
90 	if ((priv->chanmask & 0x1) && (fir & CBE_MIC_FIR_ECC_SINGLE_0_ERR)) {
91 		addreg = in_be64(&priv->regs->mic_df_ecc_address_0);
92 		clear |= CBE_MIC_FIR_ECC_SINGLE_0_RESET;
93 		cell_edac_count_ce(mci, 0, addreg);
94 	}
95 	if ((priv->chanmask & 0x2) && (fir & CBE_MIC_FIR_ECC_SINGLE_1_ERR)) {
96 		addreg = in_be64(&priv->regs->mic_df_ecc_address_1);
97 		clear |= CBE_MIC_FIR_ECC_SINGLE_1_RESET;
98 		cell_edac_count_ce(mci, 1, addreg);
99 	}
100 	if ((priv->chanmask & 0x1) && (fir & CBE_MIC_FIR_ECC_MULTI_0_ERR)) {
101 		addreg = in_be64(&priv->regs->mic_df_ecc_address_0);
102 		clear |= CBE_MIC_FIR_ECC_MULTI_0_RESET;
103 		cell_edac_count_ue(mci, 0, addreg);
104 	}
105 	if ((priv->chanmask & 0x2) && (fir & CBE_MIC_FIR_ECC_MULTI_1_ERR)) {
106 		addreg = in_be64(&priv->regs->mic_df_ecc_address_1);
107 		clear |= CBE_MIC_FIR_ECC_MULTI_1_RESET;
108 		cell_edac_count_ue(mci, 1, addreg);
109 	}
110 
111 	/* The procedure for clearing FIR bits is a bit ... weird */
112 	if (clear) {
113 		fir &= ~(CBE_MIC_FIR_ECC_ERR_MASK | CBE_MIC_FIR_ECC_SET_MASK);
114 		fir |= CBE_MIC_FIR_ECC_RESET_MASK;
115 		fir &= ~clear;
116 		out_be64(&priv->regs->mic_fir, fir);
117 		(void)in_be64(&priv->regs->mic_fir);
118 
119 		mb();	/* sync up */
120 #ifdef DEBUG
121 		fir = in_be64(&priv->regs->mic_fir);
122 		dev_dbg(mci->dev, "fir clear  : 0x%016lx\n", fir);
123 #endif
124 	}
125 }
126 
127 static void __devinit cell_edac_init_csrows(struct mem_ctl_info *mci)
128 {
129 	struct csrow_info		*csrow = &mci->csrows[0];
130 	struct dimm_info		*dimm;
131 	struct cell_edac_priv		*priv = mci->pvt_info;
132 	struct device_node		*np;
133 	int				j;
134 	u32				nr_pages;
135 
136 	for (np = NULL;
137 	     (np = of_find_node_by_name(np, "memory")) != NULL;) {
138 		struct resource r;
139 
140 		/* We "know" that the Cell firmware only creates one entry
141 		 * in the "memory" nodes. If that changes, this code will
142 		 * need to be adapted.
143 		 */
144 		if (of_address_to_resource(np, 0, &r))
145 			continue;
146 		if (of_node_to_nid(np) != priv->node)
147 			continue;
148 		csrow->first_page = r.start >> PAGE_SHIFT;
149 		nr_pages = resource_size(&r) >> PAGE_SHIFT;
150 		csrow->last_page = csrow->first_page + nr_pages - 1;
151 
152 		for (j = 0; j < csrow->nr_channels; j++) {
153 			dimm = csrow->channels[j].dimm;
154 			dimm->mtype = MEM_XDR;
155 			dimm->edac_mode = EDAC_SECDED;
156 			dimm->nr_pages = nr_pages / csrow->nr_channels;
157 		}
158 		dev_dbg(mci->dev,
159 			"Initialized on node %d, chanmask=0x%x,"
160 			" first_page=0x%lx, nr_pages=0x%x\n",
161 			priv->node, priv->chanmask,
162 			csrow->first_page, nr_pages);
163 		break;
164 	}
165 }
166 
167 static int __devinit cell_edac_probe(struct platform_device *pdev)
168 {
169 	struct cbe_mic_tm_regs __iomem	*regs;
170 	struct mem_ctl_info		*mci;
171 	struct edac_mc_layer		layers[2];
172 	struct cell_edac_priv		*priv;
173 	u64				reg;
174 	int				rc, chanmask, num_chans;
175 
176 	regs = cbe_get_cpu_mic_tm_regs(cbe_node_to_cpu(pdev->id));
177 	if (regs == NULL)
178 		return -ENODEV;
179 
180 	edac_op_state = EDAC_OPSTATE_POLL;
181 
182 	/* Get channel population */
183 	reg = in_be64(&regs->mic_mnt_cfg);
184 	dev_dbg(&pdev->dev, "MIC_MNT_CFG = 0x%016llx\n", reg);
185 	chanmask = 0;
186 	if (reg & CBE_MIC_MNT_CFG_CHAN_0_POP)
187 		chanmask |= 0x1;
188 	if (reg & CBE_MIC_MNT_CFG_CHAN_1_POP)
189 		chanmask |= 0x2;
190 	if (chanmask == 0) {
191 		dev_warn(&pdev->dev,
192 			 "Yuck ! No channel populated ? Aborting !\n");
193 		return -ENODEV;
194 	}
195 	dev_dbg(&pdev->dev, "Initial FIR = 0x%016llx\n",
196 		in_be64(&regs->mic_fir));
197 
198 	/* Allocate & init EDAC MC data structure */
199 	num_chans = chanmask == 3 ? 2 : 1;
200 
201 	layers[0].type = EDAC_MC_LAYER_CHIP_SELECT;
202 	layers[0].size = 1;
203 	layers[0].is_virt_csrow = true;
204 	layers[1].type = EDAC_MC_LAYER_CHANNEL;
205 	layers[1].size = num_chans;
206 	layers[1].is_virt_csrow = false;
207 	mci = edac_mc_alloc(pdev->id, ARRAY_SIZE(layers), layers,
208 			    sizeof(struct cell_edac_priv));
209 	if (mci == NULL)
210 		return -ENOMEM;
211 	priv = mci->pvt_info;
212 	priv->regs = regs;
213 	priv->node = pdev->id;
214 	priv->chanmask = chanmask;
215 	mci->dev = &pdev->dev;
216 	mci->mtype_cap = MEM_FLAG_XDR;
217 	mci->edac_ctl_cap = EDAC_FLAG_NONE | EDAC_FLAG_EC | EDAC_FLAG_SECDED;
218 	mci->edac_cap = EDAC_FLAG_EC | EDAC_FLAG_SECDED;
219 	mci->mod_name = "cell_edac";
220 	mci->ctl_name = "MIC";
221 	mci->dev_name = dev_name(&pdev->dev);
222 	mci->edac_check = cell_edac_check;
223 	cell_edac_init_csrows(mci);
224 
225 	/* Register with EDAC core */
226 	rc = edac_mc_add_mc(mci);
227 	if (rc) {
228 		dev_err(&pdev->dev, "failed to register with EDAC core\n");
229 		edac_mc_free(mci);
230 		return rc;
231 	}
232 
233 	return 0;
234 }
235 
236 static int __devexit cell_edac_remove(struct platform_device *pdev)
237 {
238 	struct mem_ctl_info *mci = edac_mc_del_mc(&pdev->dev);
239 	if (mci)
240 		edac_mc_free(mci);
241 	return 0;
242 }
243 
244 static struct platform_driver cell_edac_driver = {
245 	.driver		= {
246 		.name	= "cbe-mic",
247 		.owner	= THIS_MODULE,
248 	},
249 	.probe		= cell_edac_probe,
250 	.remove		= __devexit_p(cell_edac_remove),
251 };
252 
253 static int __init cell_edac_init(void)
254 {
255 	/* Sanity check registers data structure */
256 	BUILD_BUG_ON(offsetof(struct cbe_mic_tm_regs,
257 			      mic_df_ecc_address_0) != 0xf8);
258 	BUILD_BUG_ON(offsetof(struct cbe_mic_tm_regs,
259 			      mic_df_ecc_address_1) != 0x1b8);
260 	BUILD_BUG_ON(offsetof(struct cbe_mic_tm_regs,
261 			      mic_df_config) != 0x218);
262 	BUILD_BUG_ON(offsetof(struct cbe_mic_tm_regs,
263 			      mic_fir) != 0x230);
264 	BUILD_BUG_ON(offsetof(struct cbe_mic_tm_regs,
265 			      mic_mnt_cfg) != 0x210);
266 	BUILD_BUG_ON(offsetof(struct cbe_mic_tm_regs,
267 			      mic_exc) != 0x208);
268 
269 	return platform_driver_register(&cell_edac_driver);
270 }
271 
272 static void __exit cell_edac_exit(void)
273 {
274 	platform_driver_unregister(&cell_edac_driver);
275 }
276 
277 module_init(cell_edac_init);
278 module_exit(cell_edac_exit);
279 
280 MODULE_LICENSE("GPL");
281 MODULE_AUTHOR("Benjamin Herrenschmidt <benh@kernel.crashing.org>");
282 MODULE_DESCRIPTION("ECC counting for Cell MIC");
283