1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Copyright (C) 2024 Loongson Technology Corporation Limited.
4 */
5
6#include <linux/acpi.h>
7#include <linux/edac.h>
8#include <linux/init.h>
9#include <linux/io-64-nonatomic-lo-hi.h>
10#include <linux/module.h>
11#include <linux/platform_device.h>
12#include "edac_module.h"
13
14#define ECC_CS_COUNT_REG 0x18
15
16struct loongson_edac_pvt {
17 void __iomem *ecc_base;
18
19 /*
20 * The ECC register in this controller records the number of errors
21 * encountered since reset and cannot be zeroed so in order to be able
22 * to report the error count at each check, this records the previous
23 * register state.
24 */
25 int last_ce_count;
26};
27
28static int read_ecc(struct mem_ctl_info *mci)
29{
30 struct loongson_edac_pvt *pvt = mci->pvt_info;
31 u64 ecc;
32 int cs;
33
34 ecc = readq(addr: pvt->ecc_base + ECC_CS_COUNT_REG);
35 /* cs0 -- cs3 */
36 cs = ecc & 0xff;
37 cs += (ecc >> 8) & 0xff;
38 cs += (ecc >> 16) & 0xff;
39 cs += (ecc >> 24) & 0xff;
40
41 return cs;
42}
43
44static void edac_check(struct mem_ctl_info *mci)
45{
46 struct loongson_edac_pvt *pvt = mci->pvt_info;
47 int new, add;
48
49 new = read_ecc(mci);
50 add = new - pvt->last_ce_count;
51 pvt->last_ce_count = new;
52 if (add <= 0)
53 return;
54
55 edac_mc_handle_error(type: HW_EVENT_ERR_CORRECTED, mci, error_count: add,
56 page_frame_number: 0, offset_in_page: 0, syndrome: 0, top_layer: 0, mid_layer: 0, low_layer: -1, msg: "error", other_detail: "");
57}
58
59static void dimm_config_init(struct mem_ctl_info *mci)
60{
61 struct dimm_info *dimm;
62 u32 size, npages;
63
64 /* size not used */
65 size = -1;
66 npages = MiB_TO_PAGES(size);
67
68 dimm = edac_get_dimm(mci, layer0: 0, layer1: 0, layer2: 0);
69 dimm->nr_pages = npages;
70 snprintf(buf: dimm->label, size: sizeof(dimm->label),
71 fmt: "MC#%uChannel#%u_DIMM#%u", mci->mc_idx, 0, 0);
72 dimm->grain = 8;
73}
74
75static void pvt_init(struct mem_ctl_info *mci, void __iomem *vbase)
76{
77 struct loongson_edac_pvt *pvt = mci->pvt_info;
78
79 pvt->ecc_base = vbase;
80 pvt->last_ce_count = read_ecc(mci);
81}
82
83static int edac_probe(struct platform_device *pdev)
84{
85 struct edac_mc_layer layers[2];
86 struct mem_ctl_info *mci;
87 void __iomem *vbase;
88 int ret;
89
90 vbase = devm_platform_ioremap_resource(pdev, index: 0);
91 if (IS_ERR(ptr: vbase))
92 return PTR_ERR(ptr: vbase);
93
94 layers[0].type = EDAC_MC_LAYER_CHANNEL;
95 layers[0].size = 1;
96 layers[0].is_virt_csrow = false;
97 layers[1].type = EDAC_MC_LAYER_SLOT;
98 layers[1].size = 1;
99 layers[1].is_virt_csrow = true;
100 mci = edac_mc_alloc(mc_num: 0, ARRAY_SIZE(layers), layers,
101 sz_pvt: sizeof(struct loongson_edac_pvt));
102 if (mci == NULL)
103 return -ENOMEM;
104
105 mci->mc_idx = edac_device_alloc_index();
106 mci->mtype_cap = MEM_FLAG_RDDR4;
107 mci->edac_ctl_cap = EDAC_FLAG_NONE;
108 mci->edac_cap = EDAC_FLAG_NONE;
109 mci->mod_name = "loongson_edac.c";
110 mci->ctl_name = "loongson_edac_ctl";
111 mci->dev_name = "loongson_edac_dev";
112 mci->ctl_page_to_phys = NULL;
113 mci->pdev = &pdev->dev;
114 mci->error_desc.grain = 8;
115 mci->edac_check = edac_check;
116
117 pvt_init(mci, vbase);
118 dimm_config_init(mci);
119
120 ret = edac_mc_add_mc(mci);
121 if (ret) {
122 edac_dbg(0, "MC: failed edac_mc_add_mc()\n");
123 edac_mc_free(mci);
124 return ret;
125 }
126 edac_op_state = EDAC_OPSTATE_POLL;
127
128 return 0;
129}
130
131static void edac_remove(struct platform_device *pdev)
132{
133 struct mem_ctl_info *mci = edac_mc_del_mc(dev: &pdev->dev);
134
135 if (mci)
136 edac_mc_free(mci);
137}
138
139static const struct acpi_device_id loongson_edac_acpi_match[] = {
140 {"LOON0010", 0},
141 {}
142};
143MODULE_DEVICE_TABLE(acpi, loongson_edac_acpi_match);
144
145static struct platform_driver loongson_edac_driver = {
146 .probe = edac_probe,
147 .remove = edac_remove,
148 .driver = {
149 .name = "loongson-mc-edac",
150 .acpi_match_table = loongson_edac_acpi_match,
151 },
152};
153module_platform_driver(loongson_edac_driver);
154
155MODULE_LICENSE("GPL");
156MODULE_AUTHOR("Zhao Qunqin <zhaoqunqin@loongson.cn>");
157MODULE_DESCRIPTION("EDAC driver for loongson memory controller");
158

source code of linux/drivers/edac/loongson_edac.c