xref: /linux/drivers/edac/cell_edac.c (revision debc6a6927dcd833a30750b07a4c2b456b71f1be)
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 addresss */
51 	edac_mc_handle_ce(mci, csrow->first_page + pfn, offset,
52 			  syndrome, 0, chan, "");
53 }
54 
55 static void cell_edac_count_ue(struct mem_ctl_info *mci, int chan, u64 ar)
56 {
57 	struct cell_edac_priv		*priv = mci->pvt_info;
58 	struct csrow_info		*csrow = &mci->csrows[0];
59 	unsigned long			address, pfn, offset;
60 
61 	dev_dbg(mci->dev, "ECC UE err on node %d, channel %d, ar = 0x%016llx\n",
62 		priv->node, chan, ar);
63 
64 	/* Address decoding is likely a bit bogus, to dbl check */
65 	address = (ar & 0xffffffffe0000000ul) >> 29;
66 	if (priv->chanmask == 0x3)
67 		address = (address << 1) | chan;
68 	pfn = address >> PAGE_SHIFT;
69 	offset = address & ~PAGE_MASK;
70 
71 	/* TODO: Decoding of the error addresss */
72 	edac_mc_handle_ue(mci, csrow->first_page + pfn, offset, 0, "");
73 }
74 
75 static void cell_edac_check(struct mem_ctl_info *mci)
76 {
77 	struct cell_edac_priv		*priv = mci->pvt_info;
78 	u64				fir, addreg, clear = 0;
79 
80 	fir = in_be64(&priv->regs->mic_fir);
81 #ifdef DEBUG
82 	if (fir != priv->prev_fir) {
83 		dev_dbg(mci->dev, "fir change : 0x%016lx\n", fir);
84 		priv->prev_fir = fir;
85 	}
86 #endif
87 	if ((priv->chanmask & 0x1) && (fir & CBE_MIC_FIR_ECC_SINGLE_0_ERR)) {
88 		addreg = in_be64(&priv->regs->mic_df_ecc_address_0);
89 		clear |= CBE_MIC_FIR_ECC_SINGLE_0_RESET;
90 		cell_edac_count_ce(mci, 0, addreg);
91 	}
92 	if ((priv->chanmask & 0x2) && (fir & CBE_MIC_FIR_ECC_SINGLE_1_ERR)) {
93 		addreg = in_be64(&priv->regs->mic_df_ecc_address_1);
94 		clear |= CBE_MIC_FIR_ECC_SINGLE_1_RESET;
95 		cell_edac_count_ce(mci, 1, addreg);
96 	}
97 	if ((priv->chanmask & 0x1) && (fir & CBE_MIC_FIR_ECC_MULTI_0_ERR)) {
98 		addreg = in_be64(&priv->regs->mic_df_ecc_address_0);
99 		clear |= CBE_MIC_FIR_ECC_MULTI_0_RESET;
100 		cell_edac_count_ue(mci, 0, addreg);
101 	}
102 	if ((priv->chanmask & 0x2) && (fir & CBE_MIC_FIR_ECC_MULTI_1_ERR)) {
103 		addreg = in_be64(&priv->regs->mic_df_ecc_address_1);
104 		clear |= CBE_MIC_FIR_ECC_MULTI_1_RESET;
105 		cell_edac_count_ue(mci, 1, addreg);
106 	}
107 
108 	/* The procedure for clearing FIR bits is a bit ... weird */
109 	if (clear) {
110 		fir &= ~(CBE_MIC_FIR_ECC_ERR_MASK | CBE_MIC_FIR_ECC_SET_MASK);
111 		fir |= CBE_MIC_FIR_ECC_RESET_MASK;
112 		fir &= ~clear;
113 		out_be64(&priv->regs->mic_fir, fir);
114 		(void)in_be64(&priv->regs->mic_fir);
115 
116 		mb();	/* sync up */
117 #ifdef DEBUG
118 		fir = in_be64(&priv->regs->mic_fir);
119 		dev_dbg(mci->dev, "fir clear  : 0x%016lx\n", fir);
120 #endif
121 	}
122 }
123 
124 static void __devinit cell_edac_init_csrows(struct mem_ctl_info *mci)
125 {
126 	struct csrow_info		*csrow = &mci->csrows[0];
127 	struct cell_edac_priv		*priv = mci->pvt_info;
128 	struct device_node		*np;
129 
130 	for (np = NULL;
131 	     (np = of_find_node_by_name(np, "memory")) != NULL;) {
132 		struct resource r;
133 
134 		/* We "know" that the Cell firmware only creates one entry
135 		 * in the "memory" nodes. If that changes, this code will
136 		 * need to be adapted.
137 		 */
138 		if (of_address_to_resource(np, 0, &r))
139 			continue;
140 		if (of_node_to_nid(np) != priv->node)
141 			continue;
142 		csrow->first_page = r.start >> PAGE_SHIFT;
143 		csrow->nr_pages = (r.end - r.start + 1) >> PAGE_SHIFT;
144 		csrow->last_page = csrow->first_page + csrow->nr_pages - 1;
145 		csrow->mtype = MEM_XDR;
146 		csrow->edac_mode = EDAC_SECDED;
147 		dev_dbg(mci->dev,
148 			"Initialized on node %d, chanmask=0x%x,"
149 			" first_page=0x%lx, nr_pages=0x%x\n",
150 			priv->node, priv->chanmask,
151 			csrow->first_page, csrow->nr_pages);
152 		break;
153 	}
154 }
155 
156 static int __devinit cell_edac_probe(struct platform_device *pdev)
157 {
158 	struct cbe_mic_tm_regs __iomem	*regs;
159 	struct mem_ctl_info		*mci;
160 	struct cell_edac_priv		*priv;
161 	u64				reg;
162 	int				rc, chanmask;
163 
164 	regs = cbe_get_cpu_mic_tm_regs(cbe_node_to_cpu(pdev->id));
165 	if (regs == NULL)
166 		return -ENODEV;
167 
168 	edac_op_state = EDAC_OPSTATE_POLL;
169 
170 	/* Get channel population */
171 	reg = in_be64(&regs->mic_mnt_cfg);
172 	dev_dbg(&pdev->dev, "MIC_MNT_CFG = 0x%016llx\n", reg);
173 	chanmask = 0;
174 	if (reg & CBE_MIC_MNT_CFG_CHAN_0_POP)
175 		chanmask |= 0x1;
176 	if (reg & CBE_MIC_MNT_CFG_CHAN_1_POP)
177 		chanmask |= 0x2;
178 	if (chanmask == 0) {
179 		dev_warn(&pdev->dev,
180 			 "Yuck ! No channel populated ? Aborting !\n");
181 		return -ENODEV;
182 	}
183 	dev_dbg(&pdev->dev, "Initial FIR = 0x%016llx\n",
184 		in_be64(&regs->mic_fir));
185 
186 	/* Allocate & init EDAC MC data structure */
187 	mci = edac_mc_alloc(sizeof(struct cell_edac_priv), 1,
188 			    chanmask == 3 ? 2 : 1, pdev->id);
189 	if (mci == NULL)
190 		return -ENOMEM;
191 	priv = mci->pvt_info;
192 	priv->regs = regs;
193 	priv->node = pdev->id;
194 	priv->chanmask = chanmask;
195 	mci->dev = &pdev->dev;
196 	mci->mtype_cap = MEM_FLAG_XDR;
197 	mci->edac_ctl_cap = EDAC_FLAG_NONE | EDAC_FLAG_EC | EDAC_FLAG_SECDED;
198 	mci->edac_cap = EDAC_FLAG_EC | EDAC_FLAG_SECDED;
199 	mci->mod_name = "cell_edac";
200 	mci->ctl_name = "MIC";
201 	mci->dev_name = dev_name(&pdev->dev);
202 	mci->edac_check = cell_edac_check;
203 	cell_edac_init_csrows(mci);
204 
205 	/* Register with EDAC core */
206 	rc = edac_mc_add_mc(mci);
207 	if (rc) {
208 		dev_err(&pdev->dev, "failed to register with EDAC core\n");
209 		edac_mc_free(mci);
210 		return rc;
211 	}
212 
213 	return 0;
214 }
215 
216 static int __devexit cell_edac_remove(struct platform_device *pdev)
217 {
218 	struct mem_ctl_info *mci = edac_mc_del_mc(&pdev->dev);
219 	if (mci)
220 		edac_mc_free(mci);
221 	return 0;
222 }
223 
224 static struct platform_driver cell_edac_driver = {
225 	.driver		= {
226 		.name	= "cbe-mic",
227 		.owner	= THIS_MODULE,
228 	},
229 	.probe		= cell_edac_probe,
230 	.remove		= __devexit_p(cell_edac_remove),
231 };
232 
233 static int __init cell_edac_init(void)
234 {
235 	/* Sanity check registers data structure */
236 	BUILD_BUG_ON(offsetof(struct cbe_mic_tm_regs,
237 			      mic_df_ecc_address_0) != 0xf8);
238 	BUILD_BUG_ON(offsetof(struct cbe_mic_tm_regs,
239 			      mic_df_ecc_address_1) != 0x1b8);
240 	BUILD_BUG_ON(offsetof(struct cbe_mic_tm_regs,
241 			      mic_df_config) != 0x218);
242 	BUILD_BUG_ON(offsetof(struct cbe_mic_tm_regs,
243 			      mic_fir) != 0x230);
244 	BUILD_BUG_ON(offsetof(struct cbe_mic_tm_regs,
245 			      mic_mnt_cfg) != 0x210);
246 	BUILD_BUG_ON(offsetof(struct cbe_mic_tm_regs,
247 			      mic_exc) != 0x208);
248 
249 	return platform_driver_register(&cell_edac_driver);
250 }
251 
252 static void __exit cell_edac_exit(void)
253 {
254 	platform_driver_unregister(&cell_edac_driver);
255 }
256 
257 module_init(cell_edac_init);
258 module_exit(cell_edac_exit);
259 
260 MODULE_LICENSE("GPL");
261 MODULE_AUTHOR("Benjamin Herrenschmidt <benh@kernel.crashing.org>");
262 MODULE_DESCRIPTION("ECC counting for Cell MIC");
263