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 kvfree(ctx->ffdc); 59 ctx->ffdc = kvmalloc(resp_len, GFP_KERNEL); 60 if (!ctx->ffdc) { 61 ctx->ffdc_len = 0; 62 ctx->ffdc_size = 0; 63 goto done; 64 } 65 66 ctx->ffdc_size = resp_len; 67 } 68 69 notify = true; 70 ctx->sbe_error = true; 71 ctx->ffdc_len = resp_len; 72 memcpy(ctx->ffdc, resp, resp_len); 73 } 74 75 done: 76 mutex_unlock(&ctx->sbe_error_lock); 77 return notify; 78 } 79 80 static int p9_sbe_occ_send_cmd(struct occ *occ, u8 *cmd, size_t len, 81 void *resp, size_t resp_len) 82 { 83 struct p9_sbe_occ *ctx = to_p9_sbe_occ(occ); 84 int rc; 85 86 rc = fsi_occ_submit(ctx->sbe, cmd, len, resp, &resp_len); 87 if (rc < 0) { 88 if (resp_len) { 89 if (p9_sbe_occ_save_ffdc(ctx, resp, resp_len)) 90 sysfs_notify(&occ->bus_dev->kobj, NULL, 91 bin_attr_ffdc.attr.name); 92 } 93 94 return rc; 95 } 96 97 switch (((struct occ_response *)resp)->return_status) { 98 case OCC_RESP_CMD_IN_PRG: 99 rc = -ETIMEDOUT; 100 break; 101 case OCC_RESP_SUCCESS: 102 rc = 0; 103 break; 104 case OCC_RESP_CMD_INVAL: 105 case OCC_RESP_CMD_LEN_INVAL: 106 case OCC_RESP_DATA_INVAL: 107 case OCC_RESP_CHKSUM_ERR: 108 rc = -EINVAL; 109 break; 110 case OCC_RESP_INT_ERR: 111 case OCC_RESP_BAD_STATE: 112 case OCC_RESP_CRIT_EXCEPT: 113 case OCC_RESP_CRIT_INIT: 114 case OCC_RESP_CRIT_WATCHDOG: 115 case OCC_RESP_CRIT_OCB: 116 case OCC_RESP_CRIT_HW: 117 rc = -EREMOTEIO; 118 break; 119 default: 120 rc = -EPROTO; 121 } 122 123 return rc; 124 } 125 126 static int p9_sbe_occ_probe(struct platform_device *pdev) 127 { 128 int rc; 129 struct occ *occ; 130 struct p9_sbe_occ *ctx = devm_kzalloc(&pdev->dev, sizeof(*ctx), 131 GFP_KERNEL); 132 if (!ctx) 133 return -ENOMEM; 134 135 mutex_init(&ctx->sbe_error_lock); 136 137 ctx->sbe = pdev->dev.parent; 138 occ = &ctx->occ; 139 occ->bus_dev = &pdev->dev; 140 platform_set_drvdata(pdev, occ); 141 142 occ->powr_sample_time_us = 500; 143 occ->poll_cmd_data = 0x20; /* P9 OCC poll data */ 144 occ->send_cmd = p9_sbe_occ_send_cmd; 145 146 rc = occ_setup(occ); 147 if (rc == -ESHUTDOWN) 148 rc = -ENODEV; /* Host is shutdown, don't spew errors */ 149 150 if (!rc) { 151 rc = device_create_bin_file(occ->bus_dev, &bin_attr_ffdc); 152 if (rc) { 153 dev_warn(occ->bus_dev, 154 "failed to create SBE error ffdc file\n"); 155 rc = 0; 156 } 157 } 158 159 return rc; 160 } 161 162 static int p9_sbe_occ_remove(struct platform_device *pdev) 163 { 164 struct occ *occ = platform_get_drvdata(pdev); 165 struct p9_sbe_occ *ctx = to_p9_sbe_occ(occ); 166 167 device_remove_bin_file(occ->bus_dev, &bin_attr_ffdc); 168 169 ctx->sbe = NULL; 170 occ_shutdown(occ); 171 172 kvfree(ctx->ffdc); 173 174 return 0; 175 } 176 177 static struct platform_driver p9_sbe_occ_driver = { 178 .driver = { 179 .name = "occ-hwmon", 180 }, 181 .probe = p9_sbe_occ_probe, 182 .remove = p9_sbe_occ_remove, 183 }; 184 185 module_platform_driver(p9_sbe_occ_driver); 186 187 MODULE_AUTHOR("Eddie James <eajames@linux.ibm.com>"); 188 MODULE_DESCRIPTION("BMC P9 OCC hwmon driver"); 189 MODULE_LICENSE("GPL"); 190