diff options
Diffstat (limited to 'drivers/mfd/intel_pmt.c')
| -rw-r--r-- | drivers/mfd/intel_pmt.c | 223 |
1 files changed, 223 insertions, 0 deletions
diff --git a/drivers/mfd/intel_pmt.c b/drivers/mfd/intel_pmt.c new file mode 100644 index 000000000000..744b230cdcca --- /dev/null +++ b/drivers/mfd/intel_pmt.c @@ -0,0 +1,223 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Intel Platform Monitoring Technology PMT driver + * + * Copyright (c) 2020, Intel Corporation. + * All Rights Reserved. + * + * Author: David E. Box <david.e.box@linux.intel.com> + */ + +#include <linux/bits.h> +#include <linux/kernel.h> +#include <linux/mfd/core.h> +#include <linux/module.h> +#include <linux/pci.h> +#include <linux/platform_device.h> +#include <linux/pm.h> +#include <linux/pm_runtime.h> +#include <linux/types.h> + +/* Intel DVSEC capability vendor space 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 INTEL_DVSEC_ENTRY_SIZE 4 + +/* PMT capabilities */ +#define DVSEC_INTEL_ID_TELEMETRY 2 +#define DVSEC_INTEL_ID_WATCHER 3 +#define DVSEC_INTEL_ID_CRASHLOG 4 + +struct intel_dvsec_header { + u16 length; + u16 id; + u8 num_entries; + u8 entry_size; + u8 tbir; + u32 offset; +}; + +enum pmt_quirks { + /* Watcher capability not supported */ + PMT_QUIRK_NO_WATCHER = BIT(0), + + /* Crashlog capability not supported */ + PMT_QUIRK_NO_CRASHLOG = BIT(1), + + /* Use shift instead of mask to read discovery table offset */ + PMT_QUIRK_TABLE_SHIFT = BIT(2), +}; + +struct pmt_platform_info { + unsigned long quirks; +}; + +static const struct pmt_platform_info tgl_info = { + .quirks = PMT_QUIRK_NO_WATCHER | PMT_QUIRK_NO_CRASHLOG | + PMT_QUIRK_TABLE_SHIFT, +}; + +static int pmt_add_dev(struct pci_dev *pdev, struct intel_dvsec_header *header, + unsigned long quirks) +{ + struct device *dev = &pdev->dev; + struct resource *res, *tmp; + struct mfd_cell *cell; + const char *name; + int count = header->num_entries; + int size = header->entry_size; + int id = header->id; + int i; + + switch (id) { + case DVSEC_INTEL_ID_TELEMETRY: + name = "pmt_telemetry"; + break; + case DVSEC_INTEL_ID_WATCHER: + if (quirks & PMT_QUIRK_NO_WATCHER) { + dev_info(dev, "Watcher not supported\n"); + return 0; + } + name = "pmt_watcher"; + break; + case DVSEC_INTEL_ID_CRASHLOG: + if (quirks & PMT_QUIRK_NO_CRASHLOG) { + dev_info(dev, "Crashlog not supported\n"); + return 0; + } + name = "pmt_crashlog"; + break; + default: + dev_err(dev, "Unrecognized PMT capability: %d\n", id); + return -EINVAL; + } + + if (!header->num_entries || !header->entry_size) { + dev_err(dev, "Invalid count or size for %s header\n", name); + return -EINVAL; + } + + cell = devm_kzalloc(dev, sizeof(*cell), GFP_KERNEL); + if (!cell) + return -ENOMEM; + + res = devm_kcalloc(dev, count, sizeof(*res), GFP_KERNEL); + if (!res) + return -ENOMEM; + + if (quirks & PMT_QUIRK_TABLE_SHIFT) + header->offset >>= 3; + + /* + * The PMT DVSEC contains the starting offset and count for a block of + * discovery tables, each providing access to monitoring facilities for + * a section of the device. Create a resource list of these tables to + * provide to the driver. + */ + for (i = 0, tmp = res; i < count; i++, tmp++) { + tmp->start = pdev->resource[header->tbir].start + + header->offset + i * (size << 2); + tmp->end = tmp->start + (size << 2) - 1; + tmp->flags = IORESOURCE_MEM; + } + + cell->resources = res; + cell->num_resources = count; + cell->name = name; + + return devm_mfd_add_devices(dev, PLATFORM_DEVID_AUTO, cell, 1, NULL, 0, + NULL); +} + +static int pmt_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id) +{ + struct pmt_platform_info *info; + unsigned long quirks = 0; + bool found_devices = false; + int ret, pos = 0; + + ret = pcim_enable_device(pdev); + if (ret) + return ret; + + info = (struct pmt_platform_info *)id->driver_data; + + if (info) + quirks = info->quirks; + + do { + struct intel_dvsec_header header; + u32 table; + u16 vid; + + pos = pci_find_next_ext_capability(pdev, pos, PCI_EXT_CAP_ID_DVSEC); + if (!pos) + break; + + pci_read_config_word(pdev, pos + PCI_DVSEC_HEADER1, &vid); + if (vid != PCI_VENDOR_ID_INTEL) + continue; + + pci_read_config_word(pdev, pos + PCI_DVSEC_HEADER2, + &header.id); + 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 = pmt_add_dev(pdev, &header, quirks); + if (ret) { + dev_warn(&pdev->dev, + "Failed to add device for DVSEC id %d\n", + header.id); + continue; + } + + found_devices = true; + } while (true); + + if (!found_devices) + return -ENODEV; + + pm_runtime_put(&pdev->dev); + pm_runtime_allow(&pdev->dev); + + return 0; +} + +static void pmt_pci_remove(struct pci_dev *pdev) +{ + pm_runtime_forbid(&pdev->dev); + pm_runtime_get_sync(&pdev->dev); +} + +#define PCI_DEVICE_ID_INTEL_PMT_ADL 0x467d +#define PCI_DEVICE_ID_INTEL_PMT_OOBMSM 0x09a7 +#define PCI_DEVICE_ID_INTEL_PMT_TGL 0x9a0d +static const struct pci_device_id pmt_pci_ids[] = { + { PCI_DEVICE_DATA(INTEL, PMT_ADL, &tgl_info) }, + { PCI_DEVICE_DATA(INTEL, PMT_OOBMSM, NULL) }, + { PCI_DEVICE_DATA(INTEL, PMT_TGL, &tgl_info) }, + { } +}; +MODULE_DEVICE_TABLE(pci, pmt_pci_ids); + +static struct pci_driver pmt_pci_driver = { + .name = "intel-pmt", + .id_table = pmt_pci_ids, + .probe = pmt_pci_probe, + .remove = pmt_pci_remove, +}; +module_pci_driver(pmt_pci_driver); + +MODULE_AUTHOR("David E. Box <david.e.box@linux.intel.com>"); +MODULE_DESCRIPTION("Intel Platform Monitoring Technology PMT driver"); +MODULE_LICENSE("GPL v2"); |