xref: /openbmc/linux/drivers/edac/bluefield_edac.c (revision 26f54add)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Bluefield-specific EDAC driver.
4  *
5  * Copyright (c) 2019 Mellanox Technologies.
6  */
7 
8 #include <linux/acpi.h>
9 #include <linux/arm-smccc.h>
10 #include <linux/bitfield.h>
11 #include <linux/edac.h>
12 #include <linux/io.h>
13 #include <linux/module.h>
14 #include <linux/platform_device.h>
15 
16 #include "edac_module.h"
17 
18 #define DRIVER_NAME		"bluefield-edac"
19 
20 /*
21  * Mellanox BlueField EMI (External Memory Interface) register definitions.
22  */
23 
24 #define MLXBF_ECC_CNT 0x340
25 #define MLXBF_ECC_CNT__SERR_CNT GENMASK(15, 0)
26 #define MLXBF_ECC_CNT__DERR_CNT GENMASK(31, 16)
27 
28 #define MLXBF_ECC_ERR 0x348
29 #define MLXBF_ECC_ERR__SECC BIT(0)
30 #define MLXBF_ECC_ERR__DECC BIT(16)
31 
32 #define MLXBF_ECC_LATCH_SEL 0x354
33 #define MLXBF_ECC_LATCH_SEL__START BIT(24)
34 
35 #define MLXBF_ERR_ADDR_0 0x358
36 
37 #define MLXBF_ERR_ADDR_1 0x37c
38 
39 #define MLXBF_SYNDROM 0x35c
40 #define MLXBF_SYNDROM__DERR BIT(0)
41 #define MLXBF_SYNDROM__SERR BIT(1)
42 #define MLXBF_SYNDROM__SYN GENMASK(25, 16)
43 
44 #define MLXBF_ADD_INFO 0x364
45 #define MLXBF_ADD_INFO__ERR_PRANK GENMASK(9, 8)
46 
47 #define MLXBF_EDAC_MAX_DIMM_PER_MC	2
48 #define MLXBF_EDAC_ERROR_GRAIN		8
49 
50 /*
51  * Request MLNX_SIP_GET_DIMM_INFO
52  *
53  * Retrieve information about DIMM on a certain slot.
54  *
55  * Call register usage:
56  * a0: MLNX_SIP_GET_DIMM_INFO
57  * a1: (Memory controller index) << 16 | (Dimm index in memory controller)
58  * a2-7: not used.
59  *
60  * Return status:
61  * a0: MLXBF_DIMM_INFO defined below describing the DIMM.
62  * a1-3: not used.
63  */
64 #define MLNX_SIP_GET_DIMM_INFO		0x82000008
65 
66 /* Format for the SMC response about the memory information */
67 #define MLXBF_DIMM_INFO__SIZE_GB GENMASK_ULL(15, 0)
68 #define MLXBF_DIMM_INFO__IS_RDIMM BIT(16)
69 #define MLXBF_DIMM_INFO__IS_LRDIMM BIT(17)
70 #define MLXBF_DIMM_INFO__IS_NVDIMM BIT(18)
71 #define MLXBF_DIMM_INFO__RANKS GENMASK_ULL(23, 21)
72 #define MLXBF_DIMM_INFO__PACKAGE_X GENMASK_ULL(31, 24)
73 
74 struct bluefield_edac_priv {
75 	int dimm_ranks[MLXBF_EDAC_MAX_DIMM_PER_MC];
76 	void __iomem *emi_base;
77 	int dimm_per_mc;
78 };
79 
80 static u64 smc_call1(u64 smc_op, u64 smc_arg)
81 {
82 	struct arm_smccc_res res;
83 
84 	arm_smccc_smc(smc_op, smc_arg, 0, 0, 0, 0, 0, 0, &res);
85 
86 	return res.a0;
87 }
88 
89 /*
90  * Gather the ECC information from the External Memory Interface registers
91  * and report it to the edac handler.
92  */
93 static void bluefield_gather_report_ecc(struct mem_ctl_info *mci,
94 					int error_cnt,
95 					int is_single_ecc)
96 {
97 	struct bluefield_edac_priv *priv = mci->pvt_info;
98 	u32 dram_additional_info, err_prank, edea0, edea1;
99 	u32 ecc_latch_select, dram_syndrom, serr, derr, syndrom;
100 	enum hw_event_mc_err_type ecc_type;
101 	u64 ecc_dimm_addr;
102 	int ecc_dimm;
103 
104 	ecc_type = is_single_ecc ? HW_EVENT_ERR_CORRECTED :
105 				   HW_EVENT_ERR_UNCORRECTED;
106 
107 	/*
108 	 * Tell the External Memory Interface to populate the relevant
109 	 * registers with information about the last ECC error occurrence.
110 	 */
111 	ecc_latch_select = MLXBF_ECC_LATCH_SEL__START;
112 	writel(ecc_latch_select, priv->emi_base + MLXBF_ECC_LATCH_SEL);
113 
114 	/*
115 	 * Verify that the ECC reported info in the registers is of the
116 	 * same type as the one asked to report. If not, just report the
117 	 * error without the detailed information.
118 	 */
119 	dram_syndrom = readl(priv->emi_base + MLXBF_SYNDROM);
120 	serr = FIELD_GET(MLXBF_SYNDROM__SERR, dram_syndrom);
121 	derr = FIELD_GET(MLXBF_SYNDROM__DERR, dram_syndrom);
122 	syndrom = FIELD_GET(MLXBF_SYNDROM__SYN, dram_syndrom);
123 
124 	if ((is_single_ecc && !serr) || (!is_single_ecc && !derr)) {
125 		edac_mc_handle_error(ecc_type, mci, error_cnt, 0, 0, 0,
126 				     0, 0, -1, mci->ctl_name, "");
127 		return;
128 	}
129 
130 	dram_additional_info = readl(priv->emi_base + MLXBF_ADD_INFO);
131 	err_prank = FIELD_GET(MLXBF_ADD_INFO__ERR_PRANK, dram_additional_info);
132 
133 	ecc_dimm = (err_prank >= 2 && priv->dimm_ranks[0] <= 2) ? 1 : 0;
134 
135 	edea0 = readl(priv->emi_base + MLXBF_ERR_ADDR_0);
136 	edea1 = readl(priv->emi_base + MLXBF_ERR_ADDR_1);
137 
138 	ecc_dimm_addr = ((u64)edea1 << 32) | edea0;
139 
140 	edac_mc_handle_error(ecc_type, mci, error_cnt,
141 			     PFN_DOWN(ecc_dimm_addr),
142 			     offset_in_page(ecc_dimm_addr),
143 			     syndrom, ecc_dimm, 0, 0, mci->ctl_name, "");
144 }
145 
146 static void bluefield_edac_check(struct mem_ctl_info *mci)
147 {
148 	struct bluefield_edac_priv *priv = mci->pvt_info;
149 	u32 ecc_count, single_error_count, double_error_count, ecc_error = 0;
150 
151 	/*
152 	 * The memory controller might not be initialized by the firmware
153 	 * when there isn't memory, which may lead to bad register readings.
154 	 */
155 	if (mci->edac_cap == EDAC_FLAG_NONE)
156 		return;
157 
158 	ecc_count = readl(priv->emi_base + MLXBF_ECC_CNT);
159 	single_error_count = FIELD_GET(MLXBF_ECC_CNT__SERR_CNT, ecc_count);
160 	double_error_count = FIELD_GET(MLXBF_ECC_CNT__DERR_CNT, ecc_count);
161 
162 	if (single_error_count) {
163 		ecc_error |= MLXBF_ECC_ERR__SECC;
164 
165 		bluefield_gather_report_ecc(mci, single_error_count, 1);
166 	}
167 
168 	if (double_error_count) {
169 		ecc_error |= MLXBF_ECC_ERR__DECC;
170 
171 		bluefield_gather_report_ecc(mci, double_error_count, 0);
172 	}
173 
174 	/* Write to clear reported errors. */
175 	if (ecc_count)
176 		writel(ecc_error, priv->emi_base + MLXBF_ECC_ERR);
177 }
178 
179 /* Initialize the DIMMs information for the given memory controller. */
180 static void bluefield_edac_init_dimms(struct mem_ctl_info *mci)
181 {
182 	struct bluefield_edac_priv *priv = mci->pvt_info;
183 	u64 mem_ctrl_idx = mci->mc_idx;
184 	struct dimm_info *dimm;
185 	u64 smc_info, smc_arg;
186 	int is_empty = 1, i;
187 
188 	for (i = 0; i < priv->dimm_per_mc; i++) {
189 		dimm = mci->dimms[i];
190 
191 		smc_arg = mem_ctrl_idx << 16 | i;
192 		smc_info = smc_call1(MLNX_SIP_GET_DIMM_INFO, smc_arg);
193 
194 		if (!FIELD_GET(MLXBF_DIMM_INFO__SIZE_GB, smc_info)) {
195 			dimm->mtype = MEM_EMPTY;
196 			continue;
197 		}
198 
199 		is_empty = 0;
200 
201 		dimm->edac_mode = EDAC_SECDED;
202 
203 		if (FIELD_GET(MLXBF_DIMM_INFO__IS_NVDIMM, smc_info))
204 			dimm->mtype = MEM_NVDIMM;
205 		else if (FIELD_GET(MLXBF_DIMM_INFO__IS_LRDIMM, smc_info))
206 			dimm->mtype = MEM_LRDDR4;
207 		else if (FIELD_GET(MLXBF_DIMM_INFO__IS_RDIMM, smc_info))
208 			dimm->mtype = MEM_RDDR4;
209 		else
210 			dimm->mtype = MEM_DDR4;
211 
212 		dimm->nr_pages =
213 			FIELD_GET(MLXBF_DIMM_INFO__SIZE_GB, smc_info) *
214 			(SZ_1G / PAGE_SIZE);
215 		dimm->grain = MLXBF_EDAC_ERROR_GRAIN;
216 
217 		/* Mem controller for BlueField only supports x4, x8 and x16 */
218 		switch (FIELD_GET(MLXBF_DIMM_INFO__PACKAGE_X, smc_info)) {
219 		case 4:
220 			dimm->dtype = DEV_X4;
221 			break;
222 		case 8:
223 			dimm->dtype = DEV_X8;
224 			break;
225 		case 16:
226 			dimm->dtype = DEV_X16;
227 			break;
228 		default:
229 			dimm->dtype = DEV_UNKNOWN;
230 		}
231 
232 		priv->dimm_ranks[i] =
233 			FIELD_GET(MLXBF_DIMM_INFO__RANKS, smc_info);
234 	}
235 
236 	if (is_empty)
237 		mci->edac_cap = EDAC_FLAG_NONE;
238 	else
239 		mci->edac_cap = EDAC_FLAG_SECDED;
240 }
241 
242 static int bluefield_edac_mc_probe(struct platform_device *pdev)
243 {
244 	struct bluefield_edac_priv *priv;
245 	struct device *dev = &pdev->dev;
246 	struct edac_mc_layer layers[1];
247 	struct mem_ctl_info *mci;
248 	struct resource *emi_res;
249 	unsigned int mc_idx, dimm_count;
250 	int rc, ret;
251 
252 	/* Read the MSS (Memory SubSystem) index from ACPI table. */
253 	if (device_property_read_u32(dev, "mss_number", &mc_idx)) {
254 		dev_warn(dev, "bf_edac: MSS number unknown\n");
255 		return -EINVAL;
256 	}
257 
258 	/* Read the DIMMs per MC from ACPI table. */
259 	if (device_property_read_u32(dev, "dimm_per_mc", &dimm_count)) {
260 		dev_warn(dev, "bf_edac: DIMMs per MC unknown\n");
261 		return -EINVAL;
262 	}
263 
264 	if (dimm_count > MLXBF_EDAC_MAX_DIMM_PER_MC) {
265 		dev_warn(dev, "bf_edac: DIMMs per MC not valid\n");
266 		return -EINVAL;
267 	}
268 
269 	emi_res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
270 	if (!emi_res)
271 		return -EINVAL;
272 
273 	layers[0].type = EDAC_MC_LAYER_SLOT;
274 	layers[0].size = dimm_count;
275 	layers[0].is_virt_csrow = true;
276 
277 	mci = edac_mc_alloc(mc_idx, ARRAY_SIZE(layers), layers, sizeof(*priv));
278 	if (!mci)
279 		return -ENOMEM;
280 
281 	priv = mci->pvt_info;
282 
283 	priv->dimm_per_mc = dimm_count;
284 	priv->emi_base = devm_ioremap_resource(dev, emi_res);
285 	if (IS_ERR(priv->emi_base)) {
286 		dev_err(dev, "failed to map EMI IO resource\n");
287 		ret = PTR_ERR(priv->emi_base);
288 		goto err;
289 	}
290 
291 	mci->pdev = dev;
292 	mci->mtype_cap = MEM_FLAG_DDR4 | MEM_FLAG_RDDR4 |
293 			 MEM_FLAG_LRDDR4 | MEM_FLAG_NVDIMM;
294 	mci->edac_ctl_cap = EDAC_FLAG_SECDED;
295 
296 	mci->mod_name = DRIVER_NAME;
297 	mci->ctl_name = "BlueField_Memory_Controller";
298 	mci->dev_name = dev_name(dev);
299 	mci->edac_check = bluefield_edac_check;
300 
301 	/* Initialize mci with the actual populated DIMM information. */
302 	bluefield_edac_init_dimms(mci);
303 
304 	platform_set_drvdata(pdev, mci);
305 
306 	/* Register with EDAC core */
307 	rc = edac_mc_add_mc(mci);
308 	if (rc) {
309 		dev_err(dev, "failed to register with EDAC core\n");
310 		ret = rc;
311 		goto err;
312 	}
313 
314 	/* Only POLL mode supported so far. */
315 	edac_op_state = EDAC_OPSTATE_POLL;
316 
317 	return 0;
318 
319 err:
320 	edac_mc_free(mci);
321 
322 	return ret;
323 
324 }
325 
326 static int bluefield_edac_mc_remove(struct platform_device *pdev)
327 {
328 	struct mem_ctl_info *mci = platform_get_drvdata(pdev);
329 
330 	edac_mc_del_mc(&pdev->dev);
331 	edac_mc_free(mci);
332 
333 	return 0;
334 }
335 
336 static const struct acpi_device_id bluefield_mc_acpi_ids[] = {
337 	{"MLNXBF08", 0},
338 	{}
339 };
340 
341 MODULE_DEVICE_TABLE(acpi, bluefield_mc_acpi_ids);
342 
343 static struct platform_driver bluefield_edac_mc_driver = {
344 	.driver = {
345 		.name = DRIVER_NAME,
346 		.acpi_match_table = bluefield_mc_acpi_ids,
347 	},
348 	.probe = bluefield_edac_mc_probe,
349 	.remove = bluefield_edac_mc_remove,
350 };
351 
352 module_platform_driver(bluefield_edac_mc_driver);
353 
354 MODULE_DESCRIPTION("Mellanox BlueField memory edac driver");
355 MODULE_AUTHOR("Mellanox Technologies");
356 MODULE_LICENSE("GPL v2");
357