xref: /openbmc/linux/drivers/edac/cell_edac.c (revision a1e58bbd)
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/module.h>
13 #include <linux/init.h>
14 #include <linux/platform_device.h>
15 #include <linux/stop_machine.h>
16 #include <linux/io.h>
17 #include <asm/machdep.h>
18 #include <asm/cell-regs.h>
19 
20 #include "edac_core.h"
21 
22 struct cell_edac_priv
23 {
24 	struct cbe_mic_tm_regs __iomem	*regs;
25 	int				node;
26 	int				chanmask;
27 #ifdef DEBUG
28 	u64				prev_fir;
29 #endif
30 };
31 
32 static void cell_edac_count_ce(struct mem_ctl_info *mci, int chan, u64 ar)
33 {
34 	struct cell_edac_priv		*priv = mci->pvt_info;
35 	struct csrow_info		*csrow = &mci->csrows[0];
36 	unsigned long			address, pfn, offset;
37 
38 	dev_dbg(mci->dev, "ECC CE err on node %d, channel %d, ar = 0x%016lx\n",
39 		priv->node, chan, ar);
40 
41 	/* Address decoding is likely a bit bogus, to dbl check */
42 	address = (ar & 0xffffffffe0000000ul) >> 29;
43 	if (priv->chanmask == 0x3)
44 		address = (address << 1) | chan;
45 	pfn = address >> PAGE_SHIFT;
46 	offset = address & ~PAGE_MASK;
47 
48 	/* TODO: Decoding of the error addresss */
49 	edac_mc_handle_ce(mci, csrow->first_page + pfn, offset,
50 			  0, 0, chan, "");
51 }
52 
53 static void cell_edac_count_ue(struct mem_ctl_info *mci, int chan, u64 ar)
54 {
55 	struct cell_edac_priv		*priv = mci->pvt_info;
56 	struct csrow_info		*csrow = &mci->csrows[0];
57 	unsigned long			address, pfn, offset;
58 
59 	dev_dbg(mci->dev, "ECC UE err on node %d, channel %d, ar = 0x%016lx\n",
60 		priv->node, chan, ar);
61 
62 	/* Address decoding is likely a bit bogus, to dbl check */
63 	address = (ar & 0xffffffffe0000000ul) >> 29;
64 	if (priv->chanmask == 0x3)
65 		address = (address << 1) | chan;
66 	pfn = address >> PAGE_SHIFT;
67 	offset = address & ~PAGE_MASK;
68 
69 	/* TODO: Decoding of the error addresss */
70 	edac_mc_handle_ue(mci, csrow->first_page + pfn, offset, 0, "");
71 }
72 
73 static void cell_edac_check(struct mem_ctl_info *mci)
74 {
75 	struct cell_edac_priv		*priv = mci->pvt_info;
76 	u64				fir, addreg, clear = 0;
77 
78 	fir = in_be64(&priv->regs->mic_fir);
79 #ifdef DEBUG
80 	if (fir != priv->prev_fir) {
81 		dev_dbg(mci->dev, "fir change : 0x%016lx\n", fir);
82 		priv->prev_fir = fir;
83 	}
84 #endif
85 	if ((priv->chanmask & 0x1) && (fir & CBE_MIC_FIR_ECC_SINGLE_0_ERR)) {
86 		addreg = in_be64(&priv->regs->mic_df_ecc_address_0);
87 		clear |= CBE_MIC_FIR_ECC_SINGLE_0_RESET;
88 		cell_edac_count_ce(mci, 0, addreg);
89 	}
90 	if ((priv->chanmask & 0x2) && (fir & CBE_MIC_FIR_ECC_SINGLE_1_ERR)) {
91 		addreg = in_be64(&priv->regs->mic_df_ecc_address_1);
92 		clear |= CBE_MIC_FIR_ECC_SINGLE_1_RESET;
93 		cell_edac_count_ce(mci, 1, addreg);
94 	}
95 	if ((priv->chanmask & 0x1) && (fir & CBE_MIC_FIR_ECC_MULTI_0_ERR)) {
96 		addreg = in_be64(&priv->regs->mic_df_ecc_address_0);
97 		clear |= CBE_MIC_FIR_ECC_MULTI_0_RESET;
98 		cell_edac_count_ue(mci, 0, addreg);
99 	}
100 	if ((priv->chanmask & 0x2) && (fir & CBE_MIC_FIR_ECC_MULTI_1_ERR)) {
101 		addreg = in_be64(&priv->regs->mic_df_ecc_address_1);
102 		clear |= CBE_MIC_FIR_ECC_MULTI_1_RESET;
103 		cell_edac_count_ue(mci, 1, addreg);
104 	}
105 
106 	/* The procedure for clearing FIR bits is a bit ... weird */
107 	if (clear) {
108 		fir &= ~(CBE_MIC_FIR_ECC_ERR_MASK | CBE_MIC_FIR_ECC_SET_MASK);
109 		fir |= CBE_MIC_FIR_ECC_RESET_MASK;
110 		fir &= ~clear;
111 		out_be64(&priv->regs->mic_fir, fir);
112 		(void)in_be64(&priv->regs->mic_fir);
113 
114 		mb();	/* sync up */
115 #ifdef DEBUG
116 		fir = in_be64(&priv->regs->mic_fir);
117 		dev_dbg(mci->dev, "fir clear  : 0x%016lx\n", fir);
118 #endif
119 	}
120 }
121 
122 static void __devinit cell_edac_init_csrows(struct mem_ctl_info *mci)
123 {
124 	struct csrow_info		*csrow = &mci->csrows[0];
125 	struct cell_edac_priv		*priv = mci->pvt_info;
126 	struct device_node		*np;
127 
128 	for (np = NULL;
129 	     (np = of_find_node_by_name(np, "memory")) != NULL;) {
130 		struct resource r;
131 
132 		/* We "know" that the Cell firmware only creates one entry
133 		 * in the "memory" nodes. If that changes, this code will
134 		 * need to be adapted.
135 		 */
136 		if (of_address_to_resource(np, 0, &r))
137 			continue;
138 		if (of_node_to_nid(np) != priv->node)
139 			continue;
140 		csrow->first_page = r.start >> PAGE_SHIFT;
141 		csrow->nr_pages = (r.end - r.start + 1) >> PAGE_SHIFT;
142 		csrow->last_page = csrow->first_page + csrow->nr_pages - 1;
143 		csrow->mtype = MEM_XDR;
144 		csrow->edac_mode = EDAC_FLAG_EC | EDAC_FLAG_SECDED;
145 		dev_dbg(mci->dev,
146 			"Initialized on node %d, chanmask=0x%x,"
147 			" first_page=0x%lx, nr_pages=0x%x\n",
148 			priv->node, priv->chanmask,
149 			csrow->first_page, csrow->nr_pages);
150 		break;
151 	}
152 }
153 
154 static int __devinit cell_edac_probe(struct platform_device *pdev)
155 {
156 	struct cbe_mic_tm_regs __iomem	*regs;
157 	struct mem_ctl_info		*mci;
158 	struct cell_edac_priv		*priv;
159 	u64				reg;
160 	int				rc, chanmask;
161 
162 	regs = cbe_get_cpu_mic_tm_regs(cbe_node_to_cpu(pdev->id));
163 	if (regs == NULL)
164 		return -ENODEV;
165 
166 	/* Get channel population */
167 	reg = in_be64(&regs->mic_mnt_cfg);
168 	dev_dbg(&pdev->dev, "MIC_MNT_CFG = 0x%016lx\n", reg);
169 	chanmask = 0;
170 	if (reg & CBE_MIC_MNT_CFG_CHAN_0_POP)
171 		chanmask |= 0x1;
172 	if (reg & CBE_MIC_MNT_CFG_CHAN_1_POP)
173 		chanmask |= 0x2;
174 	if (chanmask == 0) {
175 		dev_warn(&pdev->dev,
176 			 "Yuck ! No channel populated ? Aborting !\n");
177 		return -ENODEV;
178 	}
179 	dev_dbg(&pdev->dev, "Initial FIR = 0x%016lx\n",
180 		in_be64(&regs->mic_fir));
181 
182 	/* Allocate & init EDAC MC data structure */
183 	mci = edac_mc_alloc(sizeof(struct cell_edac_priv), 1,
184 			    chanmask == 3 ? 2 : 1, pdev->id);
185 	if (mci == NULL)
186 		return -ENOMEM;
187 	priv = mci->pvt_info;
188 	priv->regs = regs;
189 	priv->node = pdev->id;
190 	priv->chanmask = chanmask;
191 	mci->dev = &pdev->dev;
192 	mci->mtype_cap = MEM_FLAG_XDR;
193 	mci->edac_ctl_cap = EDAC_FLAG_NONE | EDAC_FLAG_EC | EDAC_FLAG_SECDED;
194 	mci->edac_cap = EDAC_FLAG_EC | EDAC_FLAG_SECDED;
195 	mci->mod_name = "cell_edac";
196 	mci->ctl_name = "MIC";
197 	mci->dev_name = pdev->dev.bus_id;
198 	mci->edac_check = cell_edac_check;
199 	cell_edac_init_csrows(mci);
200 
201 	/* Register with EDAC core */
202 	rc = edac_mc_add_mc(mci);
203 	if (rc) {
204 		dev_err(&pdev->dev, "failed to register with EDAC core\n");
205 		edac_mc_free(mci);
206 		return rc;
207 	}
208 
209 	return 0;
210 }
211 
212 static int __devexit cell_edac_remove(struct platform_device *pdev)
213 {
214 	struct mem_ctl_info *mci = edac_mc_del_mc(&pdev->dev);
215 	if (mci)
216 		edac_mc_free(mci);
217 	return 0;
218 }
219 
220 static struct platform_driver cell_edac_driver = {
221 	.driver		= {
222 		.name	= "cbe-mic",
223 		.owner	= THIS_MODULE,
224 	},
225 	.probe		= cell_edac_probe,
226 	.remove		= cell_edac_remove,
227 };
228 
229 static int __init cell_edac_init(void)
230 {
231 	/* Sanity check registers data structure */
232 	BUILD_BUG_ON(offsetof(struct cbe_mic_tm_regs,
233 			      mic_df_ecc_address_0) != 0xf8);
234 	BUILD_BUG_ON(offsetof(struct cbe_mic_tm_regs,
235 			      mic_df_ecc_address_1) != 0x1b8);
236 	BUILD_BUG_ON(offsetof(struct cbe_mic_tm_regs,
237 			      mic_df_config) != 0x218);
238 	BUILD_BUG_ON(offsetof(struct cbe_mic_tm_regs,
239 			      mic_fir) != 0x230);
240 	BUILD_BUG_ON(offsetof(struct cbe_mic_tm_regs,
241 			      mic_mnt_cfg) != 0x210);
242 	BUILD_BUG_ON(offsetof(struct cbe_mic_tm_regs,
243 			      mic_exc) != 0x208);
244 
245 	return platform_driver_register(&cell_edac_driver);
246 }
247 
248 static void __exit cell_edac_exit(void)
249 {
250 	platform_driver_unregister(&cell_edac_driver);
251 }
252 
253 module_init(cell_edac_init);
254 module_exit(cell_edac_exit);
255 
256 MODULE_LICENSE("GPL");
257 MODULE_AUTHOR("Benjamin Herrenschmidt <benh@kernel.crashing.org>");
258 MODULE_DESCRIPTION("ECC counting for Cell MIC");
259