diff options
Diffstat (limited to 'drivers/hwmon/occ/p9_sbe.c')
-rw-r--r-- | drivers/hwmon/occ/p9_sbe.c | 205 |
1 files changed, 205 insertions, 0 deletions
diff --git a/drivers/hwmon/occ/p9_sbe.c b/drivers/hwmon/occ/p9_sbe.c new file mode 100644 index 0000000000..96521363b6 --- /dev/null +++ b/drivers/hwmon/occ/p9_sbe.c @@ -0,0 +1,205 @@ +// SPDX-License-Identifier: GPL-2.0+ +// Copyright IBM Corp 2019 + +#include <linux/device.h> +#include <linux/errno.h> +#include <linux/slab.h> +#include <linux/fsi-occ.h> +#include <linux/mm.h> +#include <linux/module.h> +#include <linux/mod_devicetable.h> +#include <linux/mutex.h> +#include <linux/platform_device.h> +#include <linux/string.h> +#include <linux/sysfs.h> + +#include "common.h" + +#define OCC_CHECKSUM_RETRIES 3 + +struct p9_sbe_occ { + struct occ occ; + bool sbe_error; + void *ffdc; + size_t ffdc_len; + size_t ffdc_size; + struct mutex sbe_error_lock; /* lock access to ffdc data */ + struct device *sbe; +}; + +#define to_p9_sbe_occ(x) container_of((x), struct p9_sbe_occ, occ) + +static ssize_t ffdc_read(struct file *filp, struct kobject *kobj, + struct bin_attribute *battr, char *buf, loff_t pos, + size_t count) +{ + ssize_t rc = 0; + struct occ *occ = dev_get_drvdata(kobj_to_dev(kobj)); + struct p9_sbe_occ *ctx = to_p9_sbe_occ(occ); + + mutex_lock(&ctx->sbe_error_lock); + if (ctx->sbe_error) { + rc = memory_read_from_buffer(buf, count, &pos, ctx->ffdc, + ctx->ffdc_len); + if (pos >= ctx->ffdc_len) + ctx->sbe_error = false; + } + mutex_unlock(&ctx->sbe_error_lock); + + return rc; +} +static BIN_ATTR_RO(ffdc, OCC_MAX_RESP_WORDS * 4); + +static bool p9_sbe_occ_save_ffdc(struct p9_sbe_occ *ctx, const void *resp, + size_t resp_len) +{ + bool notify = false; + + mutex_lock(&ctx->sbe_error_lock); + if (!ctx->sbe_error) { + if (resp_len > ctx->ffdc_size) { + kvfree(ctx->ffdc); + ctx->ffdc = kvmalloc(resp_len, GFP_KERNEL); + if (!ctx->ffdc) { + ctx->ffdc_len = 0; + ctx->ffdc_size = 0; + goto done; + } + + ctx->ffdc_size = resp_len; + } + + notify = true; + ctx->sbe_error = true; + ctx->ffdc_len = resp_len; + memcpy(ctx->ffdc, resp, resp_len); + } + +done: + mutex_unlock(&ctx->sbe_error_lock); + return notify; +} + +static int p9_sbe_occ_send_cmd(struct occ *occ, u8 *cmd, size_t len, + void *resp, size_t resp_len) +{ + size_t original_resp_len = resp_len; + struct p9_sbe_occ *ctx = to_p9_sbe_occ(occ); + int rc, i; + + for (i = 0; i < OCC_CHECKSUM_RETRIES; ++i) { + rc = fsi_occ_submit(ctx->sbe, cmd, len, resp, &resp_len); + if (rc >= 0) + break; + if (resp_len) { + if (p9_sbe_occ_save_ffdc(ctx, resp, resp_len)) + sysfs_notify(&occ->bus_dev->kobj, NULL, + bin_attr_ffdc.attr.name); + return rc; + } + if (rc != -EBADE) + return rc; + resp_len = original_resp_len; + } + + switch (((struct occ_response *)resp)->return_status) { + case OCC_RESP_CMD_IN_PRG: + rc = -ETIMEDOUT; + break; + case OCC_RESP_SUCCESS: + rc = 0; + break; + case OCC_RESP_CMD_INVAL: + case OCC_RESP_CMD_LEN_INVAL: + case OCC_RESP_DATA_INVAL: + case OCC_RESP_CHKSUM_ERR: + rc = -EINVAL; + break; + case OCC_RESP_INT_ERR: + case OCC_RESP_BAD_STATE: + case OCC_RESP_CRIT_EXCEPT: + case OCC_RESP_CRIT_INIT: + case OCC_RESP_CRIT_WATCHDOG: + case OCC_RESP_CRIT_OCB: + case OCC_RESP_CRIT_HW: + rc = -EREMOTEIO; + break; + default: + rc = -EPROTO; + } + + return rc; +} + +static int p9_sbe_occ_probe(struct platform_device *pdev) +{ + int rc; + struct occ *occ; + struct p9_sbe_occ *ctx = devm_kzalloc(&pdev->dev, sizeof(*ctx), + GFP_KERNEL); + if (!ctx) + return -ENOMEM; + + mutex_init(&ctx->sbe_error_lock); + + ctx->sbe = pdev->dev.parent; + occ = &ctx->occ; + occ->bus_dev = &pdev->dev; + platform_set_drvdata(pdev, occ); + + occ->powr_sample_time_us = 500; + occ->poll_cmd_data = 0x20; /* P9 OCC poll data */ + occ->send_cmd = p9_sbe_occ_send_cmd; + + rc = occ_setup(occ); + if (rc == -ESHUTDOWN) + rc = -ENODEV; /* Host is shutdown, don't spew errors */ + + if (!rc) { + rc = device_create_bin_file(occ->bus_dev, &bin_attr_ffdc); + if (rc) { + dev_warn(occ->bus_dev, + "failed to create SBE error ffdc file\n"); + rc = 0; + } + } + + return rc; +} + +static int p9_sbe_occ_remove(struct platform_device *pdev) +{ + struct occ *occ = platform_get_drvdata(pdev); + struct p9_sbe_occ *ctx = to_p9_sbe_occ(occ); + + device_remove_bin_file(occ->bus_dev, &bin_attr_ffdc); + + ctx->sbe = NULL; + occ_shutdown(occ); + + kvfree(ctx->ffdc); + + return 0; +} + +static const struct of_device_id p9_sbe_occ_of_match[] = { + { .compatible = "ibm,p9-occ-hwmon" }, + { .compatible = "ibm,p10-occ-hwmon" }, + {} +}; +MODULE_DEVICE_TABLE(of, p9_sbe_occ_of_match); + +static struct platform_driver p9_sbe_occ_driver = { + .driver = { + .name = "occ-hwmon", + .of_match_table = p9_sbe_occ_of_match, + }, + .probe = p9_sbe_occ_probe, + .remove = p9_sbe_occ_remove, +}; + +module_platform_driver(p9_sbe_occ_driver); + +MODULE_AUTHOR("Eddie James <eajames@linux.ibm.com>"); +MODULE_DESCRIPTION("BMC P9 OCC hwmon driver"); +MODULE_LICENSE("GPL"); |