xref: /openbmc/linux/drivers/edac/cell_edac.c (revision 384740dc)
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, syndrome;
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 	syndrome = (ar & 0x000000001fe00000ul) >> 21;
48 
49 	/* TODO: Decoding of the error addresss */
50 	edac_mc_handle_ce(mci, csrow->first_page + pfn, offset,
51 			  syndrome, 0, chan, "");
52 }
53 
54 static void cell_edac_count_ue(struct mem_ctl_info *mci, int chan, u64 ar)
55 {
56 	struct cell_edac_priv		*priv = mci->pvt_info;
57 	struct csrow_info		*csrow = &mci->csrows[0];
58 	unsigned long			address, pfn, offset;
59 
60 	dev_dbg(mci->dev, "ECC UE err on node %d, channel %d, ar = 0x%016lx\n",
61 		priv->node, chan, ar);
62 
63 	/* Address decoding is likely a bit bogus, to dbl check */
64 	address = (ar & 0xffffffffe0000000ul) >> 29;
65 	if (priv->chanmask == 0x3)
66 		address = (address << 1) | chan;
67 	pfn = address >> PAGE_SHIFT;
68 	offset = address & ~PAGE_MASK;
69 
70 	/* TODO: Decoding of the error addresss */
71 	edac_mc_handle_ue(mci, csrow->first_page + pfn, offset, 0, "");
72 }
73 
74 static void cell_edac_check(struct mem_ctl_info *mci)
75 {
76 	struct cell_edac_priv		*priv = mci->pvt_info;
77 	u64				fir, addreg, clear = 0;
78 
79 	fir = in_be64(&priv->regs->mic_fir);
80 #ifdef DEBUG
81 	if (fir != priv->prev_fir) {
82 		dev_dbg(mci->dev, "fir change : 0x%016lx\n", fir);
83 		priv->prev_fir = fir;
84 	}
85 #endif
86 	if ((priv->chanmask & 0x1) && (fir & CBE_MIC_FIR_ECC_SINGLE_0_ERR)) {
87 		addreg = in_be64(&priv->regs->mic_df_ecc_address_0);
88 		clear |= CBE_MIC_FIR_ECC_SINGLE_0_RESET;
89 		cell_edac_count_ce(mci, 0, addreg);
90 	}
91 	if ((priv->chanmask & 0x2) && (fir & CBE_MIC_FIR_ECC_SINGLE_1_ERR)) {
92 		addreg = in_be64(&priv->regs->mic_df_ecc_address_1);
93 		clear |= CBE_MIC_FIR_ECC_SINGLE_1_RESET;
94 		cell_edac_count_ce(mci, 1, addreg);
95 	}
96 	if ((priv->chanmask & 0x1) && (fir & CBE_MIC_FIR_ECC_MULTI_0_ERR)) {
97 		addreg = in_be64(&priv->regs->mic_df_ecc_address_0);
98 		clear |= CBE_MIC_FIR_ECC_MULTI_0_RESET;
99 		cell_edac_count_ue(mci, 0, addreg);
100 	}
101 	if ((priv->chanmask & 0x2) && (fir & CBE_MIC_FIR_ECC_MULTI_1_ERR)) {
102 		addreg = in_be64(&priv->regs->mic_df_ecc_address_1);
103 		clear |= CBE_MIC_FIR_ECC_MULTI_1_RESET;
104 		cell_edac_count_ue(mci, 1, addreg);
105 	}
106 
107 	/* The procedure for clearing FIR bits is a bit ... weird */
108 	if (clear) {
109 		fir &= ~(CBE_MIC_FIR_ECC_ERR_MASK | CBE_MIC_FIR_ECC_SET_MASK);
110 		fir |= CBE_MIC_FIR_ECC_RESET_MASK;
111 		fir &= ~clear;
112 		out_be64(&priv->regs->mic_fir, fir);
113 		(void)in_be64(&priv->regs->mic_fir);
114 
115 		mb();	/* sync up */
116 #ifdef DEBUG
117 		fir = in_be64(&priv->regs->mic_fir);
118 		dev_dbg(mci->dev, "fir clear  : 0x%016lx\n", fir);
119 #endif
120 	}
121 }
122 
123 static void __devinit cell_edac_init_csrows(struct mem_ctl_info *mci)
124 {
125 	struct csrow_info		*csrow = &mci->csrows[0];
126 	struct cell_edac_priv		*priv = mci->pvt_info;
127 	struct device_node		*np;
128 
129 	for (np = NULL;
130 	     (np = of_find_node_by_name(np, "memory")) != NULL;) {
131 		struct resource r;
132 
133 		/* We "know" that the Cell firmware only creates one entry
134 		 * in the "memory" nodes. If that changes, this code will
135 		 * need to be adapted.
136 		 */
137 		if (of_address_to_resource(np, 0, &r))
138 			continue;
139 		if (of_node_to_nid(np) != priv->node)
140 			continue;
141 		csrow->first_page = r.start >> PAGE_SHIFT;
142 		csrow->nr_pages = (r.end - r.start + 1) >> PAGE_SHIFT;
143 		csrow->last_page = csrow->first_page + csrow->nr_pages - 1;
144 		csrow->mtype = MEM_XDR;
145 		csrow->edac_mode = EDAC_FLAG_EC | EDAC_FLAG_SECDED;
146 		dev_dbg(mci->dev,
147 			"Initialized on node %d, chanmask=0x%x,"
148 			" first_page=0x%lx, nr_pages=0x%x\n",
149 			priv->node, priv->chanmask,
150 			csrow->first_page, csrow->nr_pages);
151 		break;
152 	}
153 }
154 
155 static int __devinit cell_edac_probe(struct platform_device *pdev)
156 {
157 	struct cbe_mic_tm_regs __iomem	*regs;
158 	struct mem_ctl_info		*mci;
159 	struct cell_edac_priv		*priv;
160 	u64				reg;
161 	int				rc, chanmask;
162 
163 	regs = cbe_get_cpu_mic_tm_regs(cbe_node_to_cpu(pdev->id));
164 	if (regs == NULL)
165 		return -ENODEV;
166 
167 	/* Get channel population */
168 	reg = in_be64(&regs->mic_mnt_cfg);
169 	dev_dbg(&pdev->dev, "MIC_MNT_CFG = 0x%016lx\n", reg);
170 	chanmask = 0;
171 	if (reg & CBE_MIC_MNT_CFG_CHAN_0_POP)
172 		chanmask |= 0x1;
173 	if (reg & CBE_MIC_MNT_CFG_CHAN_1_POP)
174 		chanmask |= 0x2;
175 	if (chanmask == 0) {
176 		dev_warn(&pdev->dev,
177 			 "Yuck ! No channel populated ? Aborting !\n");
178 		return -ENODEV;
179 	}
180 	dev_dbg(&pdev->dev, "Initial FIR = 0x%016lx\n",
181 		in_be64(&regs->mic_fir));
182 
183 	/* Allocate & init EDAC MC data structure */
184 	mci = edac_mc_alloc(sizeof(struct cell_edac_priv), 1,
185 			    chanmask == 3 ? 2 : 1, pdev->id);
186 	if (mci == NULL)
187 		return -ENOMEM;
188 	priv = mci->pvt_info;
189 	priv->regs = regs;
190 	priv->node = pdev->id;
191 	priv->chanmask = chanmask;
192 	mci->dev = &pdev->dev;
193 	mci->mtype_cap = MEM_FLAG_XDR;
194 	mci->edac_ctl_cap = EDAC_FLAG_NONE | EDAC_FLAG_EC | EDAC_FLAG_SECDED;
195 	mci->edac_cap = EDAC_FLAG_EC | EDAC_FLAG_SECDED;
196 	mci->mod_name = "cell_edac";
197 	mci->ctl_name = "MIC";
198 	mci->dev_name = pdev->dev.bus_id;
199 	mci->edac_check = cell_edac_check;
200 	cell_edac_init_csrows(mci);
201 
202 	/* Register with EDAC core */
203 	rc = edac_mc_add_mc(mci);
204 	if (rc) {
205 		dev_err(&pdev->dev, "failed to register with EDAC core\n");
206 		edac_mc_free(mci);
207 		return rc;
208 	}
209 
210 	return 0;
211 }
212 
213 static int __devexit cell_edac_remove(struct platform_device *pdev)
214 {
215 	struct mem_ctl_info *mci = edac_mc_del_mc(&pdev->dev);
216 	if (mci)
217 		edac_mc_free(mci);
218 	return 0;
219 }
220 
221 static struct platform_driver cell_edac_driver = {
222 	.driver		= {
223 		.name	= "cbe-mic",
224 		.owner	= THIS_MODULE,
225 	},
226 	.probe		= cell_edac_probe,
227 	.remove		= cell_edac_remove,
228 };
229 
230 static int __init cell_edac_init(void)
231 {
232 	/* Sanity check registers data structure */
233 	BUILD_BUG_ON(offsetof(struct cbe_mic_tm_regs,
234 			      mic_df_ecc_address_0) != 0xf8);
235 	BUILD_BUG_ON(offsetof(struct cbe_mic_tm_regs,
236 			      mic_df_ecc_address_1) != 0x1b8);
237 	BUILD_BUG_ON(offsetof(struct cbe_mic_tm_regs,
238 			      mic_df_config) != 0x218);
239 	BUILD_BUG_ON(offsetof(struct cbe_mic_tm_regs,
240 			      mic_fir) != 0x230);
241 	BUILD_BUG_ON(offsetof(struct cbe_mic_tm_regs,
242 			      mic_mnt_cfg) != 0x210);
243 	BUILD_BUG_ON(offsetof(struct cbe_mic_tm_regs,
244 			      mic_exc) != 0x208);
245 
246 	return platform_driver_register(&cell_edac_driver);
247 }
248 
249 static void __exit cell_edac_exit(void)
250 {
251 	platform_driver_unregister(&cell_edac_driver);
252 }
253 
254 module_init(cell_edac_init);
255 module_exit(cell_edac_exit);
256 
257 MODULE_LICENSE("GPL");
258 MODULE_AUTHOR("Benjamin Herrenschmidt <benh@kernel.crashing.org>");
259 MODULE_DESCRIPTION("ECC counting for Cell MIC");
260