diff options
Diffstat (limited to 'drivers/platform/x86/intel/vsec.c')
| -rw-r--r-- | drivers/platform/x86/intel/vsec.c | 408 |
1 files changed, 408 insertions, 0 deletions
diff --git a/drivers/platform/x86/intel/vsec.c b/drivers/platform/x86/intel/vsec.c new file mode 100644 index 000000000000..c3bdd75ed690 --- /dev/null +++ b/drivers/platform/x86/intel/vsec.c @@ -0,0 +1,408 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Intel Vendor Specific Extended Capabilities auxiliary bus driver + * + * Copyright (c) 2021, Intel Corporation. + * All Rights Reserved. + * + * Author: David E. Box <david.e.box@linux.intel.com> + * + * This driver discovers and creates auxiliary devices for Intel defined PCIe + * "Vendor Specific" and "Designated Vendor Specific" Extended Capabilities, + * VSEC and DVSEC respectively. The driver supports features on specific PCIe + * endpoints that exist primarily to expose them. + */ + +#include <linux/auxiliary_bus.h> +#include <linux/bits.h> +#include <linux/kernel.h> +#include <linux/idr.h> +#include <linux/module.h> +#include <linux/pci.h> +#include <linux/types.h> + +#include "vsec.h" + +/* Intel DVSEC offsets */ +#define INTEL_DVSEC_ENTRIES 0xA +#define INTEL_DVSEC_SIZE 0xB +#define INTEL_DVSEC_TABLE 0xC +#define INTEL_DVSEC_TABLE_BAR(x) ((x) & GENMASK(2, 0)) +#define INTEL_DVSEC_TABLE_OFFSET(x) ((x) & GENMASK(31, 3)) +#define TABLE_OFFSET_SHIFT 3 + +static DEFINE_IDA(intel_vsec_ida); + +/** + * struct intel_vsec_header - Common fields of Intel VSEC and DVSEC registers. + * @rev: Revision ID of the VSEC/DVSEC register space + * @length: Length of the VSEC/DVSEC register space + * @id: ID of the feature + * @num_entries: Number of instances of the feature + * @entry_size: Size of the discovery table for each feature + * @tbir: BAR containing the discovery tables + * @offset: BAR offset of start of the first discovery table + */ +struct intel_vsec_header { + u8 rev; + u16 length; + u16 id; + u8 num_entries; + u8 entry_size; + u8 tbir; + u32 offset; +}; + +/* Platform specific data */ +struct intel_vsec_platform_info { + struct intel_vsec_header **capabilities; + unsigned long quirks; +}; + +enum intel_vsec_id { + VSEC_ID_TELEMETRY = 2, + VSEC_ID_WATCHER = 3, + VSEC_ID_CRASHLOG = 4, +}; + +static enum intel_vsec_id intel_vsec_allow_list[] = { + VSEC_ID_TELEMETRY, + VSEC_ID_WATCHER, + VSEC_ID_CRASHLOG, +}; + +static const char *intel_vsec_name(enum intel_vsec_id id) +{ + switch (id) { + case VSEC_ID_TELEMETRY: + return "telemetry"; + + case VSEC_ID_WATCHER: + return "watcher"; + + case VSEC_ID_CRASHLOG: + return "crashlog"; + + default: + return NULL; + } +} + +static bool intel_vsec_allowed(u16 id) +{ + int i; + + for (i = 0; i < ARRAY_SIZE(intel_vsec_allow_list); i++) + if (intel_vsec_allow_list[i] == id) + return true; + + return false; +} + +static bool intel_vsec_disabled(u16 id, unsigned long quirks) +{ + switch (id) { + case VSEC_ID_WATCHER: + return !!(quirks & VSEC_QUIRK_NO_WATCHER); + + case VSEC_ID_CRASHLOG: + return !!(quirks & VSEC_QUIRK_NO_CRASHLOG); + + default: + return false; + } +} + +static void intel_vsec_remove_aux(void *data) +{ + auxiliary_device_delete(data); + auxiliary_device_uninit(data); +} + +static void intel_vsec_dev_release(struct device *dev) +{ + struct intel_vsec_device *intel_vsec_dev = dev_to_ivdev(dev); + + ida_free(intel_vsec_dev->ida, intel_vsec_dev->auxdev.id); + kfree(intel_vsec_dev->resource); + kfree(intel_vsec_dev); +} + +static int intel_vsec_add_aux(struct pci_dev *pdev, struct intel_vsec_device *intel_vsec_dev, + const char *name) +{ + struct auxiliary_device *auxdev = &intel_vsec_dev->auxdev; + int ret; + + ret = ida_alloc(intel_vsec_dev->ida, GFP_KERNEL); + if (ret < 0) { + kfree(intel_vsec_dev); + return ret; + } + + auxdev->id = ret; + auxdev->name = name; + auxdev->dev.parent = &pdev->dev; + auxdev->dev.release = intel_vsec_dev_release; + + ret = auxiliary_device_init(auxdev); + if (ret < 0) { + ida_free(intel_vsec_dev->ida, auxdev->id); + kfree(intel_vsec_dev->resource); + kfree(intel_vsec_dev); + return ret; + } + + ret = auxiliary_device_add(auxdev); + if (ret < 0) { + auxiliary_device_uninit(auxdev); + return ret; + } + + return devm_add_action_or_reset(&pdev->dev, intel_vsec_remove_aux, auxdev); +} + +static int intel_vsec_add_dev(struct pci_dev *pdev, struct intel_vsec_header *header, + unsigned long quirks) +{ + struct intel_vsec_device *intel_vsec_dev; + struct resource *res, *tmp; + int i; + + if (!intel_vsec_allowed(header->id) || intel_vsec_disabled(header->id, quirks)) + return -EINVAL; + + if (!header->num_entries) { + dev_dbg(&pdev->dev, "Invalid 0 entry count for header id %d\n", header->id); + return -EINVAL; + } + + if (!header->entry_size) { + dev_dbg(&pdev->dev, "Invalid 0 entry size for header id %d\n", header->id); + return -EINVAL; + } + + intel_vsec_dev = kzalloc(sizeof(*intel_vsec_dev), GFP_KERNEL); + if (!intel_vsec_dev) + return -ENOMEM; + + res = kcalloc(header->num_entries, sizeof(*res), GFP_KERNEL); + if (!res) { + kfree(intel_vsec_dev); + return -ENOMEM; + } + + if (quirks & VSEC_QUIRK_TABLE_SHIFT) + header->offset >>= TABLE_OFFSET_SHIFT; + + /* + * The DVSEC/VSEC contains the starting offset and count for a block of + * discovery tables. Create a resource array of these tables to the + * auxiliary device driver. + */ + for (i = 0, tmp = res; i < header->num_entries; i++, tmp++) { + tmp->start = pdev->resource[header->tbir].start + + header->offset + i * (header->entry_size * sizeof(u32)); + tmp->end = tmp->start + (header->entry_size * sizeof(u32)) - 1; + tmp->flags = IORESOURCE_MEM; + } + + intel_vsec_dev->pcidev = pdev; + intel_vsec_dev->resource = res; + intel_vsec_dev->num_resources = header->num_entries; + intel_vsec_dev->quirks = quirks; + intel_vsec_dev->ida = &intel_vsec_ida; + + return intel_vsec_add_aux(pdev, intel_vsec_dev, intel_vsec_name(header->id)); +} + +static bool intel_vsec_walk_header(struct pci_dev *pdev, unsigned long quirks, + struct intel_vsec_header **header) +{ + bool have_devices = false; + int ret; + + for ( ; *header; header++) { + ret = intel_vsec_add_dev(pdev, *header, quirks); + if (ret) + dev_info(&pdev->dev, "Could not add device for DVSEC id %d\n", + (*header)->id); + else + have_devices = true; + } + + return have_devices; +} + +static bool intel_vsec_walk_dvsec(struct pci_dev *pdev, unsigned long quirks) +{ + bool have_devices = false; + int pos = 0; + + do { + struct intel_vsec_header header; + u32 table, hdr; + u16 vid; + int ret; + + pos = pci_find_next_ext_capability(pdev, pos, PCI_EXT_CAP_ID_DVSEC); + if (!pos) + break; + + pci_read_config_dword(pdev, pos + PCI_DVSEC_HEADER1, &hdr); + vid = PCI_DVSEC_HEADER1_VID(hdr); + if (vid != PCI_VENDOR_ID_INTEL) + continue; + + /* Support only revision 1 */ + header.rev = PCI_DVSEC_HEADER1_REV(hdr); + if (header.rev != 1) { + dev_info(&pdev->dev, "Unsupported DVSEC revision %d\n", header.rev); + continue; + } + + header.length = PCI_DVSEC_HEADER1_LEN(hdr); + + pci_read_config_byte(pdev, pos + INTEL_DVSEC_ENTRIES, &header.num_entries); + pci_read_config_byte(pdev, pos + INTEL_DVSEC_SIZE, &header.entry_size); + pci_read_config_dword(pdev, pos + INTEL_DVSEC_TABLE, &table); + + header.tbir = INTEL_DVSEC_TABLE_BAR(table); + header.offset = INTEL_DVSEC_TABLE_OFFSET(table); + + pci_read_config_dword(pdev, pos + PCI_DVSEC_HEADER2, &hdr); + header.id = PCI_DVSEC_HEADER2_ID(hdr); + + ret = intel_vsec_add_dev(pdev, &header, quirks); + if (ret) + continue; + + have_devices = true; + } while (true); + + return have_devices; +} + +static bool intel_vsec_walk_vsec(struct pci_dev *pdev, unsigned long quirks) +{ + bool have_devices = false; + int pos = 0; + + do { + struct intel_vsec_header header; + u32 table, hdr; + int ret; + + pos = pci_find_next_ext_capability(pdev, pos, PCI_EXT_CAP_ID_VNDR); + if (!pos) + break; + + pci_read_config_dword(pdev, pos + PCI_VNDR_HEADER, &hdr); + + /* Support only revision 1 */ + header.rev = PCI_VNDR_HEADER_REV(hdr); + if (header.rev != 1) { + dev_info(&pdev->dev, "Unsupported VSEC revision %d\n", header.rev); + continue; + } + + header.id = PCI_VNDR_HEADER_ID(hdr); + header.length = PCI_VNDR_HEADER_LEN(hdr); + + /* entry, size, and table offset are the same as DVSEC */ + pci_read_config_byte(pdev, pos + INTEL_DVSEC_ENTRIES, &header.num_entries); + pci_read_config_byte(pdev, pos + INTEL_DVSEC_SIZE, &header.entry_size); + pci_read_config_dword(pdev, pos + INTEL_DVSEC_TABLE, &table); + + header.tbir = INTEL_DVSEC_TABLE_BAR(table); + header.offset = INTEL_DVSEC_TABLE_OFFSET(table); + + ret = intel_vsec_add_dev(pdev, &header, quirks); + if (ret) + continue; + + have_devices = true; + } while (true); + + return have_devices; +} + +static int intel_vsec_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id) +{ + struct intel_vsec_platform_info *info; + bool have_devices = false; + unsigned long quirks = 0; + int ret; + + ret = pcim_enable_device(pdev); + if (ret) + return ret; + + info = (struct intel_vsec_platform_info *)id->driver_data; + if (info) + quirks = info->quirks; + + if (intel_vsec_walk_dvsec(pdev, quirks)) + have_devices = true; + + if (intel_vsec_walk_vsec(pdev, quirks)) + have_devices = true; + + if (info && (info->quirks & VSEC_QUIRK_NO_DVSEC) && + intel_vsec_walk_header(pdev, quirks, info->capabilities)) + have_devices = true; + + if (!have_devices) + return -ENODEV; + + return 0; +} + +/* TGL info */ +static const struct intel_vsec_platform_info tgl_info = { + .quirks = VSEC_QUIRK_NO_WATCHER | VSEC_QUIRK_NO_CRASHLOG | VSEC_QUIRK_TABLE_SHIFT, +}; + +/* DG1 info */ +static struct intel_vsec_header dg1_telemetry = { + .length = 0x10, + .id = 2, + .num_entries = 1, + .entry_size = 3, + .tbir = 0, + .offset = 0x466000, +}; + +static struct intel_vsec_header *dg1_capabilities[] = { + &dg1_telemetry, + NULL +}; + +static const struct intel_vsec_platform_info dg1_info = { + .capabilities = dg1_capabilities, + .quirks = VSEC_QUIRK_NO_DVSEC, +}; + +#define PCI_DEVICE_ID_INTEL_VSEC_ADL 0x467d +#define PCI_DEVICE_ID_INTEL_VSEC_DG1 0x490e +#define PCI_DEVICE_ID_INTEL_VSEC_OOBMSM 0x09a7 +#define PCI_DEVICE_ID_INTEL_VSEC_TGL 0x9a0d +static const struct pci_device_id intel_vsec_pci_ids[] = { + { PCI_DEVICE_DATA(INTEL, VSEC_ADL, &tgl_info) }, + { PCI_DEVICE_DATA(INTEL, VSEC_DG1, &dg1_info) }, + { PCI_DEVICE_DATA(INTEL, VSEC_OOBMSM, NULL) }, + { PCI_DEVICE_DATA(INTEL, VSEC_TGL, &tgl_info) }, + { } +}; +MODULE_DEVICE_TABLE(pci, intel_vsec_pci_ids); + +static struct pci_driver intel_vsec_pci_driver = { + .name = "intel_vsec", + .id_table = intel_vsec_pci_ids, + .probe = intel_vsec_pci_probe, +}; +module_pci_driver(intel_vsec_pci_driver); + +MODULE_AUTHOR("David E. Box <david.e.box@linux.intel.com>"); +MODULE_DESCRIPTION("Intel Extended Capabilities auxiliary bus driver"); +MODULE_LICENSE("GPL v2"); |