1 // SPDX-License-Identifier: GPL-2.0+ 2 // Copyright IBM Corp 2019 3 4 #include <linux/device.h> 5 #include <linux/errno.h> 6 #include <linux/slab.h> 7 #include <linux/fsi-occ.h> 8 #include <linux/mm.h> 9 #include <linux/module.h> 10 #include <linux/mutex.h> 11 #include <linux/platform_device.h> 12 #include <linux/string.h> 13 #include <linux/sysfs.h> 14 15 #include "common.h" 16 17 struct p9_sbe_occ { 18 struct occ occ; 19 bool sbe_error; 20 void *ffdc; 21 size_t ffdc_len; 22 size_t ffdc_size; 23 struct mutex sbe_error_lock; /* lock access to ffdc data */ 24 struct device *sbe; 25 }; 26 27 #define to_p9_sbe_occ(x) container_of((x), struct p9_sbe_occ, occ) 28 29 static ssize_t ffdc_read(struct file *filp, struct kobject *kobj, 30 struct bin_attribute *battr, char *buf, loff_t pos, 31 size_t count) 32 { 33 ssize_t rc = 0; 34 struct occ *occ = dev_get_drvdata(kobj_to_dev(kobj)); 35 struct p9_sbe_occ *ctx = to_p9_sbe_occ(occ); 36 37 mutex_lock(&ctx->sbe_error_lock); 38 if (ctx->sbe_error) { 39 rc = memory_read_from_buffer(buf, count, &pos, ctx->ffdc, 40 ctx->ffdc_len); 41 if (pos >= ctx->ffdc_len) 42 ctx->sbe_error = false; 43 } 44 mutex_unlock(&ctx->sbe_error_lock); 45 46 return rc; 47 } 48 static BIN_ATTR_RO(ffdc, OCC_MAX_RESP_WORDS * 4); 49 50 static bool p9_sbe_occ_save_ffdc(struct p9_sbe_occ *ctx, const void *resp, 51 size_t resp_len) 52 { 53 bool notify = false; 54 55 mutex_lock(&ctx->sbe_error_lock); 56 if (!ctx->sbe_error) { 57 if (resp_len > ctx->ffdc_size) { 58 if (ctx->ffdc) 59 kvfree(ctx->ffdc); 60 ctx->ffdc = kvmalloc(resp_len, GFP_KERNEL); 61 if (!ctx->ffdc) { 62 ctx->ffdc_len = 0; 63 ctx->ffdc_size = 0; 64 goto done; 65 } 66 67 ctx->ffdc_size = resp_len; 68 } 69 70 notify = true; 71 ctx->sbe_error = true; 72 ctx->ffdc_len = resp_len; 73 memcpy(ctx->ffdc, resp, resp_len); 74 } 75 76 done: 77 mutex_unlock(&ctx->sbe_error_lock); 78 return notify; 79 } 80 81 static int p9_sbe_occ_send_cmd(struct occ *occ, u8 *cmd, size_t len, 82 void *resp, size_t resp_len) 83 { 84 struct p9_sbe_occ *ctx = to_p9_sbe_occ(occ); 85 int rc; 86 87 rc = fsi_occ_submit(ctx->sbe, cmd, len, resp, &resp_len); 88 if (rc < 0) { 89 if (resp_len) { 90 if (p9_sbe_occ_save_ffdc(ctx, resp, resp_len)) 91 sysfs_notify(&occ->bus_dev->kobj, NULL, 92 bin_attr_ffdc.attr.name); 93 } 94 95 return rc; 96 } 97 98 switch (((struct occ_response *)resp)->return_status) { 99 case OCC_RESP_CMD_IN_PRG: 100 rc = -ETIMEDOUT; 101 break; 102 case OCC_RESP_SUCCESS: 103 rc = 0; 104 break; 105 case OCC_RESP_CMD_INVAL: 106 case OCC_RESP_CMD_LEN_INVAL: 107 case OCC_RESP_DATA_INVAL: 108 case OCC_RESP_CHKSUM_ERR: 109 rc = -EINVAL; 110 break; 111 case OCC_RESP_INT_ERR: 112 case OCC_RESP_BAD_STATE: 113 case OCC_RESP_CRIT_EXCEPT: 114 case OCC_RESP_CRIT_INIT: 115 case OCC_RESP_CRIT_WATCHDOG: 116 case OCC_RESP_CRIT_OCB: 117 case OCC_RESP_CRIT_HW: 118 rc = -EREMOTEIO; 119 break; 120 default: 121 rc = -EPROTO; 122 } 123 124 return rc; 125 } 126 127 static int p9_sbe_occ_probe(struct platform_device *pdev) 128 { 129 int rc; 130 struct occ *occ; 131 struct p9_sbe_occ *ctx = devm_kzalloc(&pdev->dev, sizeof(*ctx), 132 GFP_KERNEL); 133 if (!ctx) 134 return -ENOMEM; 135 136 mutex_init(&ctx->sbe_error_lock); 137 138 ctx->sbe = pdev->dev.parent; 139 occ = &ctx->occ; 140 occ->bus_dev = &pdev->dev; 141 platform_set_drvdata(pdev, occ); 142 143 occ->powr_sample_time_us = 500; 144 occ->poll_cmd_data = 0x20; /* P9 OCC poll data */ 145 occ->send_cmd = p9_sbe_occ_send_cmd; 146 147 rc = occ_setup(occ); 148 if (rc == -ESHUTDOWN) 149 rc = -ENODEV; /* Host is shutdown, don't spew errors */ 150 151 if (!rc) { 152 rc = device_create_bin_file(occ->bus_dev, &bin_attr_ffdc); 153 if (rc) { 154 dev_warn(occ->bus_dev, 155 "failed to create SBE error ffdc file\n"); 156 rc = 0; 157 } 158 } 159 160 return rc; 161 } 162 163 static int p9_sbe_occ_remove(struct platform_device *pdev) 164 { 165 struct occ *occ = platform_get_drvdata(pdev); 166 struct p9_sbe_occ *ctx = to_p9_sbe_occ(occ); 167 168 device_remove_bin_file(occ->bus_dev, &bin_attr_ffdc); 169 170 ctx->sbe = NULL; 171 occ_shutdown(occ); 172 173 if (ctx->ffdc) 174 kvfree(ctx->ffdc); 175 176 return 0; 177 } 178 179 static struct platform_driver p9_sbe_occ_driver = { 180 .driver = { 181 .name = "occ-hwmon", 182 }, 183 .probe = p9_sbe_occ_probe, 184 .remove = p9_sbe_occ_remove, 185 }; 186 187 module_platform_driver(p9_sbe_occ_driver); 188 189 MODULE_AUTHOR("Eddie James <eajames@linux.ibm.com>"); 190 MODULE_DESCRIPTION("BMC P9 OCC hwmon driver"); 191 MODULE_LICENSE("GPL"); 192