diff options
Diffstat (limited to 'drivers/platform/x86/intel/pmt/telemetry.c')
| -rw-r--r-- | drivers/platform/x86/intel/pmt/telemetry.c | 163 |
1 files changed, 163 insertions, 0 deletions
diff --git a/drivers/platform/x86/intel/pmt/telemetry.c b/drivers/platform/x86/intel/pmt/telemetry.c new file mode 100644 index 0000000000..39cbc87cc2 --- /dev/null +++ b/drivers/platform/x86/intel/pmt/telemetry.c @@ -0,0 +1,163 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Intel Platform Monitory Technology Telemetry driver + * + * Copyright (c) 2020, Intel Corporation. + * All Rights Reserved. + * + * Author: "David E. Box" <david.e.box@linux.intel.com> + */ + +#include <linux/auxiliary_bus.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/pci.h> +#include <linux/slab.h> +#include <linux/uaccess.h> +#include <linux/overflow.h> + +#include "../vsec.h" +#include "class.h" + +#define TELEM_SIZE_OFFSET 0x0 +#define TELEM_GUID_OFFSET 0x4 +#define TELEM_BASE_OFFSET 0x8 +#define TELEM_ACCESS(v) ((v) & GENMASK(3, 0)) +#define TELEM_TYPE(v) (((v) & GENMASK(7, 4)) >> 4) +/* size is in bytes */ +#define TELEM_SIZE(v) (((v) & GENMASK(27, 12)) >> 10) + +/* Used by client hardware to identify a fixed telemetry entry*/ +#define TELEM_CLIENT_FIXED_BLOCK_GUID 0x10000000 + +enum telem_type { + TELEM_TYPE_PUNIT = 0, + TELEM_TYPE_CRASHLOG, + TELEM_TYPE_PUNIT_FIXED, +}; + +struct pmt_telem_priv { + int num_entries; + struct intel_pmt_entry entry[]; +}; + +static bool pmt_telem_region_overlaps(struct intel_pmt_entry *entry, + struct device *dev) +{ + u32 guid = readl(entry->disc_table + TELEM_GUID_OFFSET); + + if (intel_pmt_is_early_client_hw(dev)) { + u32 type = TELEM_TYPE(readl(entry->disc_table)); + + if ((type == TELEM_TYPE_PUNIT_FIXED) || + (guid == TELEM_CLIENT_FIXED_BLOCK_GUID)) + return true; + } + + return false; +} + +static int pmt_telem_header_decode(struct intel_pmt_entry *entry, + struct intel_pmt_header *header, + struct device *dev) +{ + void __iomem *disc_table = entry->disc_table; + + if (pmt_telem_region_overlaps(entry, dev)) + return 1; + + header->access_type = TELEM_ACCESS(readl(disc_table)); + header->guid = readl(disc_table + TELEM_GUID_OFFSET); + header->base_offset = readl(disc_table + TELEM_BASE_OFFSET); + + /* Size is measured in DWORDS, but accessor returns bytes */ + header->size = TELEM_SIZE(readl(disc_table)); + + /* + * Some devices may expose non-functioning entries that are + * reserved for future use. They have zero size. Do not fail + * probe for these. Just ignore them. + */ + if (header->size == 0 || header->access_type == 0xF) + return 1; + + return 0; +} + +static DEFINE_XARRAY_ALLOC(telem_array); +static struct intel_pmt_namespace pmt_telem_ns = { + .name = "telem", + .xa = &telem_array, + .pmt_header_decode = pmt_telem_header_decode, +}; + +static void pmt_telem_remove(struct auxiliary_device *auxdev) +{ + struct pmt_telem_priv *priv = auxiliary_get_drvdata(auxdev); + int i; + + for (i = 0; i < priv->num_entries; i++) + intel_pmt_dev_destroy(&priv->entry[i], &pmt_telem_ns); +} + +static int pmt_telem_probe(struct auxiliary_device *auxdev, const struct auxiliary_device_id *id) +{ + struct intel_vsec_device *intel_vsec_dev = auxdev_to_ivdev(auxdev); + struct pmt_telem_priv *priv; + size_t size; + int i, ret; + + size = struct_size(priv, entry, intel_vsec_dev->num_resources); + priv = devm_kzalloc(&auxdev->dev, size, GFP_KERNEL); + if (!priv) + return -ENOMEM; + + auxiliary_set_drvdata(auxdev, priv); + + for (i = 0; i < intel_vsec_dev->num_resources; i++) { + struct intel_pmt_entry *entry = &priv->entry[priv->num_entries]; + + ret = intel_pmt_dev_create(entry, &pmt_telem_ns, intel_vsec_dev, i); + if (ret < 0) + goto abort_probe; + if (ret) + continue; + + priv->num_entries++; + } + + return 0; +abort_probe: + pmt_telem_remove(auxdev); + return ret; +} + +static const struct auxiliary_device_id pmt_telem_id_table[] = { + { .name = "intel_vsec.telemetry" }, + {} +}; +MODULE_DEVICE_TABLE(auxiliary, pmt_telem_id_table); + +static struct auxiliary_driver pmt_telem_aux_driver = { + .id_table = pmt_telem_id_table, + .remove = pmt_telem_remove, + .probe = pmt_telem_probe, +}; + +static int __init pmt_telem_init(void) +{ + return auxiliary_driver_register(&pmt_telem_aux_driver); +} +module_init(pmt_telem_init); + +static void __exit pmt_telem_exit(void) +{ + auxiliary_driver_unregister(&pmt_telem_aux_driver); + xa_destroy(&telem_array); +} +module_exit(pmt_telem_exit); + +MODULE_AUTHOR("David E. Box <david.e.box@linux.intel.com>"); +MODULE_DESCRIPTION("Intel PMT Telemetry driver"); +MODULE_LICENSE("GPL v2"); +MODULE_IMPORT_NS(INTEL_PMT); |