diff options
| -rw-r--r-- | drivers/platform/x86/intel/vsec.c | 223 | ||||
| -rw-r--r-- | include/linux/intel_vsec.h | 28 |
2 files changed, 236 insertions, 15 deletions
diff --git a/drivers/platform/x86/intel/vsec.c b/drivers/platform/x86/intel/vsec.c index 8bdb74d86f240..aa1f7e63039d0 100644 --- a/drivers/platform/x86/intel/vsec.c +++ b/drivers/platform/x86/intel/vsec.c @@ -15,9 +15,12 @@ #include <linux/auxiliary_bus.h> #include <linux/bits.h> +#include <linux/bitops.h> +#include <linux/bug.h> #include <linux/cleanup.h> #include <linux/delay.h> #include <linux/idr.h> +#include <linux/log2.h> #include <linux/intel_vsec.h> #include <linux/kernel.h> #include <linux/module.h> @@ -32,8 +35,17 @@ static DEFINE_IDA(intel_vsec_ida); static DEFINE_IDA(intel_vsec_sdsi_ida); static DEFINE_XARRAY_ALLOC(auxdev_array); +enum vsec_device_state { + STATE_NOT_FOUND, + STATE_REGISTERED, + STATE_SKIP, +}; + struct vsec_priv { struct intel_vsec_platform_info *info; + struct device *suppliers[VSEC_FEATURE_COUNT]; + enum vsec_device_state state[VSEC_FEATURE_COUNT]; + unsigned long found_caps; }; static const char *intel_vsec_name(enum intel_vsec_id id) @@ -95,6 +107,74 @@ static void intel_vsec_dev_release(struct device *dev) kfree(intel_vsec_dev); } +static const struct vsec_feature_dependency * +get_consumer_dependencies(struct vsec_priv *priv, int cap_id) +{ + const struct vsec_feature_dependency *deps = priv->info->deps; + int consumer_id = priv->info->num_deps; + + if (!deps) + return NULL; + + while (consumer_id--) + if (deps[consumer_id].feature == BIT(cap_id)) + return &deps[consumer_id]; + + return NULL; +} + +/* + * Although pci_device_id table is available in the pdev, this prototype is + * necessary because the code using it can be called by an exported API that + * might pass a different pdev. + */ +static const struct pci_device_id intel_vsec_pci_ids[]; + +static int intel_vsec_link_devices(struct pci_dev *pdev, struct device *dev, + int consumer_id) +{ + const struct vsec_feature_dependency *deps; + enum vsec_device_state *state; + struct device **suppliers; + struct vsec_priv *priv; + int supplier_id; + + if (!consumer_id) + return 0; + + if (!pci_match_id(intel_vsec_pci_ids, pdev)) + return 0; + + priv = pci_get_drvdata(pdev); + state = priv->state; + suppliers = priv->suppliers; + + priv->suppliers[consumer_id] = dev; + + deps = get_consumer_dependencies(priv, consumer_id); + if (!deps) + return 0; + + for_each_set_bit(supplier_id, &deps->supplier_bitmap, VSEC_FEATURE_COUNT) { + struct device_link *link; + + if (state[supplier_id] != STATE_REGISTERED) + continue; + + if (!suppliers[supplier_id]) { + dev_err(dev, "Bad supplier list\n"); + return -EINVAL; + } + + link = device_link_add(dev, suppliers[supplier_id], + DL_FLAG_AUTOPROBE_CONSUMER); + if (!link) + return -EINVAL; + } + + return 0; +} + int intel_vsec_add_aux(struct pci_dev *pdev, struct device *parent, struct intel_vsec_device *intel_vsec_dev, const char *name) @@ -132,19 +212,37 @@ int intel_vsec_add_aux(struct pci_dev *pdev, struct device *parent, return ret; } + /* + * Assign a name now to ensure that the device link doesn't contain + * a null string for the consumer name. This is a problem when a supplier + * supplies more than one consumer and can lead to a duplicate name error + * when the link is created in sysfs. + */ + ret = dev_set_name(&auxdev->dev, "%s.%s.%d", KBUILD_MODNAME, auxdev->name, + auxdev->id); + if (ret) + goto cleanup_aux; + + ret = intel_vsec_link_devices(pdev, &auxdev->dev, intel_vsec_dev->cap_id); + if (ret) + goto cleanup_aux; + ret = auxiliary_device_add(auxdev); - if (ret < 0) { - auxiliary_device_uninit(auxdev); - return ret; - } + if (ret) + goto cleanup_aux; return devm_add_action_or_reset(parent, intel_vsec_remove_aux, auxdev); + +cleanup_aux: + auxiliary_device_uninit(auxdev); + return ret; } EXPORT_SYMBOL_NS_GPL(intel_vsec_add_aux, "INTEL_VSEC"); static int intel_vsec_add_dev(struct pci_dev *pdev, struct intel_vsec_header *header, - struct intel_vsec_platform_info *info) + struct intel_vsec_platform_info *info, + unsigned long cap_id) { struct intel_vsec_device __free(kfree) *intel_vsec_dev = NULL; struct resource __free(kfree) *res = NULL; @@ -211,6 +309,7 @@ static int intel_vsec_add_dev(struct pci_dev *pdev, struct intel_vsec_header *he intel_vsec_dev->quirks = info->quirks; intel_vsec_dev->base_addr = info->base_addr; intel_vsec_dev->priv_data = info->priv_data; + intel_vsec_dev->cap_id = cap_id; if (header->id == VSEC_ID_SDSI) intel_vsec_dev->ida = &intel_vsec_sdsi_ida; @@ -225,6 +324,101 @@ static int intel_vsec_add_dev(struct pci_dev *pdev, struct intel_vsec_header *he intel_vsec_name(header->id)); } +static bool suppliers_ready(struct vsec_priv *priv, + const struct vsec_feature_dependency *consumer_deps, + int cap_id) +{ + enum vsec_device_state *state = priv->state; + int supplier_id; + + if (WARN_ON_ONCE(consumer_deps->feature != BIT(cap_id))) + return false; + + /* + * Verify that all required suppliers have been found. Return false + * immediately if any are still missing. + */ + for_each_set_bit(supplier_id, &consumer_deps->supplier_bitmap, VSEC_FEATURE_COUNT) { + if (state[supplier_id] == STATE_SKIP) + continue; + + if (state[supplier_id] == STATE_NOT_FOUND) + return false; + } + + /* + * All suppliers have been found and the consumer is ready to be + * registered. + */ + return true; +} + +static int get_cap_id(u32 header_id, unsigned long *cap_id) +{ + switch (header_id) { + case VSEC_ID_TELEMETRY: + *cap_id = ilog2(VSEC_CAP_TELEMETRY); + break; + case VSEC_ID_WATCHER: + *cap_id = ilog2(VSEC_CAP_WATCHER); + break; + case VSEC_ID_CRASHLOG: + *cap_id = ilog2(VSEC_CAP_CRASHLOG); + break; + case VSEC_ID_SDSI: + *cap_id = ilog2(VSEC_CAP_SDSI); + break; + case VSEC_ID_TPMI: + *cap_id = ilog2(VSEC_CAP_TPMI); + break; + default: + return -EINVAL; + } + + return 0; +} + +static int intel_vsec_register_device(struct pci_dev *pdev, + struct intel_vsec_header *header, + struct intel_vsec_platform_info *info) +{ + const struct vsec_feature_dependency *consumer_deps; + struct vsec_priv *priv; + unsigned long cap_id; + int ret; + + ret = get_cap_id(header->id, &cap_id); + if (ret) + return ret; + + /* + * Only track dependencies for devices probed by the VSEC driver. + * For others using the exported APIs, add the device directly. + */ + if (!pci_match_id(intel_vsec_pci_ids, pdev)) + return intel_vsec_add_dev(pdev, header, info, cap_id); + + priv = pci_get_drvdata(pdev); + if (priv->state[cap_id] == STATE_REGISTERED || + priv->state[cap_id] == STATE_SKIP) + return -EEXIST; + + priv->found_caps |= BIT(cap_id); + + consumer_deps = get_consumer_dependencies(priv, cap_id); + if (!consumer_deps || suppliers_ready(priv, consumer_deps, cap_id)) { + ret = intel_vsec_add_dev(pdev, header, info, cap_id); + if (ret) + priv->state[cap_id] = STATE_SKIP; + else + priv->state[cap_id] = STATE_REGISTERED; + + return ret; + } + + return -EAGAIN; +} + static bool intel_vsec_walk_header(struct pci_dev *pdev, struct intel_vsec_platform_info *info) { @@ -233,7 +427,7 @@ static bool intel_vsec_walk_header(struct pci_dev *pdev, int ret; for ( ; *header; header++) { - ret = intel_vsec_add_dev(pdev, *header, info); + ret = intel_vsec_register_device(pdev, *header, info); if (!ret) have_devices = true; } @@ -281,7 +475,7 @@ static bool intel_vsec_walk_dvsec(struct pci_dev *pdev, pci_read_config_dword(pdev, pos + PCI_DVSEC_HEADER2, &hdr); header.id = PCI_DVSEC_HEADER2_ID(hdr); - ret = intel_vsec_add_dev(pdev, &header, info); + ret = intel_vsec_register_device(pdev, &header, info); if (ret) continue; @@ -326,7 +520,7 @@ static bool intel_vsec_walk_vsec(struct pci_dev *pdev, header.tbir = INTEL_DVSEC_TABLE_BAR(table); header.offset = INTEL_DVSEC_TABLE_OFFSET(table); - ret = intel_vsec_add_dev(pdev, &header, info); + ret = intel_vsec_register_device(pdev, &header, info); if (ret) continue; @@ -378,7 +572,8 @@ static int intel_vsec_pci_probe(struct pci_dev *pdev, const struct pci_device_id { struct intel_vsec_platform_info *info; struct vsec_priv *priv; - int ret; + int num_caps, ret; + bool found_any = false; ret = pcim_enable_device(pdev); if (ret) @@ -396,7 +591,15 @@ static int intel_vsec_pci_probe(struct pci_dev *pdev, const struct pci_device_id priv->info = info; pci_set_drvdata(pdev, priv); - if (!intel_vsec_get_features(pdev, info)) + num_caps = hweight_long(info->caps); + while (num_caps--) { + found_any |= intel_vsec_get_features(pdev, info); + + if (priv->found_caps == info->caps) + break; + } + + if (!found_any) return -ENODEV; return 0; diff --git a/include/linux/intel_vsec.h b/include/linux/intel_vsec.h index bc95821f1bfb2..71067afaca992 100644 --- a/include/linux/intel_vsec.h +++ b/include/linux/intel_vsec.h @@ -5,11 +5,18 @@ #include <linux/auxiliary_bus.h> #include <linux/bits.h> -#define VSEC_CAP_TELEMETRY BIT(0) -#define VSEC_CAP_WATCHER BIT(1) -#define VSEC_CAP_CRASHLOG BIT(2) -#define VSEC_CAP_SDSI BIT(3) -#define VSEC_CAP_TPMI BIT(4) +/* + * VSEC_CAP_UNUSED is reserved. It exists to prevent zero initialized + * intel_vsec devices from being automatically set to a known + * capability with ID 0 + */ +#define VSEC_CAP_UNUSED BIT(0) +#define VSEC_CAP_TELEMETRY BIT(1) +#define VSEC_CAP_WATCHER BIT(2) +#define VSEC_CAP_CRASHLOG BIT(3) +#define VSEC_CAP_SDSI BIT(4) +#define VSEC_CAP_TPMI BIT(5) +#define VSEC_FEATURE_COUNT 6 /* Intel DVSEC offsets */ #define INTEL_DVSEC_ENTRIES 0xA @@ -81,22 +88,31 @@ struct pmt_callbacks { int (*read_telem)(struct pci_dev *pdev, u32 guid, u64 *data, loff_t off, u32 count); }; +struct vsec_feature_dependency { + unsigned long feature; + unsigned long supplier_bitmap; +}; + /** * struct intel_vsec_platform_info - Platform specific data * @parent: parent device in the auxbus chain * @headers: list of headers to define the PMT client devices to create + * @deps: array of feature dependencies * @priv_data: private data, usable by parent devices, currently a callback * @caps: bitmask of PMT capabilities for the given headers * @quirks: bitmask of VSEC device quirks * @base_addr: allow a base address to be specified (rather than derived) + * @num_deps: Count feature dependencies */ struct intel_vsec_platform_info { struct device *parent; struct intel_vsec_header **headers; + const struct vsec_feature_dependency *deps; void *priv_data; unsigned long caps; unsigned long quirks; u64 base_addr; + int num_deps; }; /** @@ -110,6 +126,7 @@ struct intel_vsec_platform_info { * @priv_data: any private data needed * @quirks: specified quirks * @base_addr: base address of entries (if specified) + * @cap_id: the enumerated id of the vsec feature */ struct intel_vsec_device { struct auxiliary_device auxdev; @@ -122,6 +139,7 @@ struct intel_vsec_device { size_t priv_data_size; unsigned long quirks; u64 base_addr; + unsigned long cap_id; }; int intel_vsec_add_aux(struct pci_dev *pdev, struct device *parent, |