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Box" To: linux-kernel@vger.kernel.org, platform-driver-x86@vger.kernel.org, ilpo.jarvinen@linux.intel.com, rajvi.jingar@linux.intel.com Subject: [PATCH V3 07/16] platform/x86/intel/pmt: telemetry: Export API to read telemetry Date: Wed, 11 Oct 2023 19:38:31 -0700 Message-Id: <20231012023840.3845703-8-david.e.box@linux.intel.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20231012023840.3845703-1-david.e.box@linux.intel.com> References: <20231012023840.3845703-1-david.e.box@linux.intel.com> MIME-Version: 1.0 X-Spam-Status: No, score=-2.0 required=5.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_EF,RCVD_IN_DNSWL_BLOCKED, SPF_HELO_NONE,SPF_NONE autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lindbergh.monkeyblade.net Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org X-Greylist: Sender passed SPF test, not delayed by milter-greylist-4.6.4 (snail.vger.email [0.0.0.0]); Wed, 11 Oct 2023 19:39:10 -0700 (PDT) X-getmail-retrieved-from-mailbox: INBOX X-GMAIL-THRID: 1779515629749875095 X-GMAIL-MSGID: 1779515629749875095 Export symbols to allow access to Intel PMT Telemetry data on available devices. Provides APIs to search, register, and read telemetry using a kref managed pointer that serves as a handle to a telemetry endpoint. To simplify searching for present devices, have the IDA start at 1 instead of 0 so that 0 can be used to indicate end of search. Signed-off-by: David E. Box Reviewed-by: Ilpo Järvinen --- V3 - Add comment for mutex lock - Fix multiline comments - Fix line lengths - Fix space/tab inconsistences in header doc V2 - Add explanation of PMT_XA_START change in changelog - change return and argument type of pmt_telem_get_next_endpoint() to unsigned long - style fixes drivers/platform/x86/intel/pmt/class.c | 21 ++- drivers/platform/x86/intel/pmt/class.h | 14 ++ drivers/platform/x86/intel/pmt/telemetry.c | 191 ++++++++++++++++++++- drivers/platform/x86/intel/pmt/telemetry.h | 126 ++++++++++++++ 4 files changed, 344 insertions(+), 8 deletions(-) create mode 100644 drivers/platform/x86/intel/pmt/telemetry.h diff --git a/drivers/platform/x86/intel/pmt/class.c b/drivers/platform/x86/intel/pmt/class.c index 142a24e3727d..4b53940a64e2 100644 --- a/drivers/platform/x86/intel/pmt/class.c +++ b/drivers/platform/x86/intel/pmt/class.c @@ -17,7 +17,7 @@ #include "../vsec.h" #include "class.h" -#define PMT_XA_START 0 +#define PMT_XA_START 1 #define PMT_XA_MAX INT_MAX #define PMT_XA_LIMIT XA_LIMIT(PMT_XA_START, PMT_XA_MAX) #define GUID_SPR_PUNIT 0x9956f43f @@ -247,6 +247,7 @@ static int intel_pmt_dev_register(struct intel_pmt_entry *entry, struct intel_pmt_namespace *ns, struct device *parent) { + struct intel_vsec_device *ivdev = dev_to_ivdev(parent); struct resource res = {0}; struct device *dev; int ret; @@ -270,7 +271,7 @@ static int intel_pmt_dev_register(struct intel_pmt_entry *entry, if (ns->attr_grp) { ret = sysfs_create_group(entry->kobj, ns->attr_grp); if (ret) - goto fail_sysfs; + goto fail_sysfs_create_group; } /* if size is 0 assume no data buffer, so no file needed */ @@ -295,13 +296,23 @@ static int intel_pmt_dev_register(struct intel_pmt_entry *entry, entry->pmt_bin_attr.size = entry->size; ret = sysfs_create_bin_file(&dev->kobj, &entry->pmt_bin_attr); - if (!ret) - return 0; + if (ret) + goto fail_ioremap; + if (ns->pmt_add_endpoint) { + ret = ns->pmt_add_endpoint(entry, ivdev->pcidev); + if (ret) + goto fail_add_endpoint; + } + + return 0; + +fail_add_endpoint: + sysfs_remove_bin_file(entry->kobj, &entry->pmt_bin_attr); fail_ioremap: if (ns->attr_grp) sysfs_remove_group(entry->kobj, ns->attr_grp); -fail_sysfs: +fail_sysfs_create_group: device_unregister(dev); fail_dev_create: xa_erase(ns->xa, entry->devid); diff --git a/drivers/platform/x86/intel/pmt/class.h b/drivers/platform/x86/intel/pmt/class.h index e477a19f6700..d23c63b73ab7 100644 --- a/drivers/platform/x86/intel/pmt/class.h +++ b/drivers/platform/x86/intel/pmt/class.h @@ -9,6 +9,7 @@ #include #include "../vsec.h" +#include "telemetry.h" /* PMT access types */ #define ACCESS_BARID 2 @@ -18,6 +19,16 @@ #define GET_BIR(v) ((v) & GENMASK(2, 0)) #define GET_ADDRESS(v) ((v) & GENMASK(31, 3)) +struct pci_dev; + +struct telem_endpoint { + struct pci_dev *pcidev; + struct telem_header header; + void __iomem *base; + bool present; + struct kref kref; +}; + struct intel_pmt_header { u32 base_offset; u32 size; @@ -26,6 +37,7 @@ struct intel_pmt_header { }; struct intel_pmt_entry { + struct telem_endpoint *ep; struct intel_pmt_header header; struct bin_attribute pmt_bin_attr; struct kobject *kobj; @@ -43,6 +55,8 @@ struct intel_pmt_namespace { const struct attribute_group *attr_grp; int (*pmt_header_decode)(struct intel_pmt_entry *entry, struct device *dev); + int (*pmt_add_endpoint)(struct intel_pmt_entry *entry, + struct pci_dev *pdev); }; bool intel_pmt_is_early_client_hw(struct device *dev); diff --git a/drivers/platform/x86/intel/pmt/telemetry.c b/drivers/platform/x86/intel/pmt/telemetry.c index f86080e8bebd..09258564dfc4 100644 --- a/drivers/platform/x86/intel/pmt/telemetry.c +++ b/drivers/platform/x86/intel/pmt/telemetry.c @@ -30,6 +30,15 @@ /* Used by client hardware to identify a fixed telemetry entry*/ #define TELEM_CLIENT_FIXED_BLOCK_GUID 0x10000000 +#define NUM_BYTES_QWORD(v) ((v) << 3) +#define SAMPLE_ID_OFFSET(v) ((v) << 3) + +#define NUM_BYTES_DWORD(v) ((v) << 2) +#define SAMPLE_ID_OFFSET32(v) ((v) << 2) + +/* Protects access to the xarray of telemetry endpoint handles */ +static DEFINE_MUTEX(ep_lock); + enum telem_type { TELEM_TYPE_PUNIT = 0, TELEM_TYPE_CRASHLOG, @@ -84,21 +93,195 @@ static int pmt_telem_header_decode(struct intel_pmt_entry *entry, return 0; } +static int pmt_telem_add_endpoint(struct intel_pmt_entry *entry, + struct pci_dev *pdev) +{ + struct telem_endpoint *ep; + + /* Endpoint lifetimes are managed by kref, not devres */ + entry->ep = kzalloc(sizeof(*(entry->ep)), GFP_KERNEL); + if (!entry->ep) + return -ENOMEM; + + ep = entry->ep; + ep->pcidev = pdev; + ep->header.access_type = entry->header.access_type; + ep->header.guid = entry->header.guid; + ep->header.base_offset = entry->header.base_offset; + ep->header.size = entry->header.size; + ep->base = entry->base; + ep->present = true; + + kref_init(&ep->kref); + + 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, + .pmt_add_endpoint = pmt_telem_add_endpoint, }; +/* Called when all users unregister and the device is removed */ +static void pmt_telem_ep_release(struct kref *kref) +{ + struct telem_endpoint *ep; + + ep = container_of(kref, struct telem_endpoint, kref); + kfree(ep); +} + +unsigned long pmt_telem_get_next_endpoint(unsigned long start) +{ + struct intel_pmt_entry *entry; + unsigned long found_idx; + + mutex_lock(&ep_lock); + xa_for_each_start(&telem_array, found_idx, entry, start) { + /* + * Return first found index after start. + * 0 is not valid id. + */ + if (found_idx > start) + break; + } + mutex_unlock(&ep_lock); + + return found_idx == start ? 0 : found_idx; +} +EXPORT_SYMBOL_NS_GPL(pmt_telem_get_next_endpoint, INTEL_PMT_TELEMETRY); + +struct telem_endpoint *pmt_telem_register_endpoint(int devid) +{ + struct intel_pmt_entry *entry; + unsigned long index = devid; + + mutex_lock(&ep_lock); + entry = xa_find(&telem_array, &index, index, XA_PRESENT); + if (!entry) { + mutex_unlock(&ep_lock); + return ERR_PTR(-ENXIO); + } + + kref_get(&entry->ep->kref); + mutex_unlock(&ep_lock); + + return entry->ep; +} +EXPORT_SYMBOL_NS_GPL(pmt_telem_register_endpoint, INTEL_PMT_TELEMETRY); + +void pmt_telem_unregister_endpoint(struct telem_endpoint *ep) +{ + kref_put(&ep->kref, pmt_telem_ep_release); +} +EXPORT_SYMBOL_NS_GPL(pmt_telem_unregister_endpoint, INTEL_PMT_TELEMETRY); + +int pmt_telem_get_endpoint_info(int devid, struct telem_endpoint_info *info) +{ + struct intel_pmt_entry *entry; + unsigned long index = devid; + int err = 0; + + if (!info) + return -EINVAL; + + mutex_lock(&ep_lock); + entry = xa_find(&telem_array, &index, index, XA_PRESENT); + if (!entry) { + err = -ENXIO; + goto unlock; + } + + info->pdev = entry->ep->pcidev; + info->header = entry->ep->header; + +unlock: + mutex_unlock(&ep_lock); + return err; + +} +EXPORT_SYMBOL_NS_GPL(pmt_telem_get_endpoint_info, INTEL_PMT_TELEMETRY); + +int pmt_telem_read(struct telem_endpoint *ep, u32 id, u64 *data, u32 count) +{ + u32 offset, size; + + if (!ep->present) + return -ENODEV; + + offset = SAMPLE_ID_OFFSET(id); + size = ep->header.size; + + if (offset + NUM_BYTES_QWORD(count) > size) + return -EINVAL; + + memcpy_fromio(data, ep->base + offset, NUM_BYTES_QWORD(count)); + + return ep->present ? 0 : -EPIPE; +} +EXPORT_SYMBOL_NS_GPL(pmt_telem_read, INTEL_PMT_TELEMETRY); + +int pmt_telem_read32(struct telem_endpoint *ep, u32 id, u32 *data, u32 count) +{ + u32 offset, size; + + if (!ep->present) + return -ENODEV; + + offset = SAMPLE_ID_OFFSET32(id); + size = ep->header.size; + + if (offset + NUM_BYTES_DWORD(count) > size) + return -EINVAL; + + memcpy_fromio(data, ep->base + offset, NUM_BYTES_DWORD(count)); + + return ep->present ? 0 : -EPIPE; +} +EXPORT_SYMBOL_NS_GPL(pmt_telem_read32, INTEL_PMT_TELEMETRY); + +struct telem_endpoint * +pmt_telem_find_and_register_endpoint(struct pci_dev *pcidev, u32 guid, u16 pos) +{ + int devid = 0; + int inst = 0; + int err = 0; + + while ((devid = pmt_telem_get_next_endpoint(devid))) { + struct telem_endpoint_info ep_info; + + err = pmt_telem_get_endpoint_info(devid, &ep_info); + if (err) + return ERR_PTR(err); + + if (ep_info.header.guid == guid && ep_info.pdev == pcidev) { + if (inst == pos) + return pmt_telem_register_endpoint(devid); + ++inst; + } + } + + return ERR_PTR(-ENXIO); +} +EXPORT_SYMBOL_NS_GPL(pmt_telem_find_and_register_endpoint, INTEL_PMT_TELEMETRY); + 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); -} + mutex_lock(&ep_lock); + for (i = 0; i < priv->num_entries; i++) { + struct intel_pmt_entry *entry = &priv->entry[i]; + + kref_put(&entry->ep->kref, pmt_telem_ep_release); + intel_pmt_dev_destroy(entry, &pmt_telem_ns); + } + mutex_unlock(&ep_lock); +}; static int pmt_telem_probe(struct auxiliary_device *auxdev, const struct auxiliary_device_id *id) { @@ -117,7 +300,9 @@ static int pmt_telem_probe(struct auxiliary_device *auxdev, const struct auxilia for (i = 0; i < intel_vsec_dev->num_resources; i++) { struct intel_pmt_entry *entry = &priv->entry[priv->num_entries]; + mutex_lock(&ep_lock); ret = intel_pmt_dev_create(entry, &pmt_telem_ns, intel_vsec_dev, i); + mutex_unlock(&ep_lock); if (ret < 0) goto abort_probe; if (ret) diff --git a/drivers/platform/x86/intel/pmt/telemetry.h b/drivers/platform/x86/intel/pmt/telemetry.h new file mode 100644 index 000000000000..d45af5512b4e --- /dev/null +++ b/drivers/platform/x86/intel/pmt/telemetry.h @@ -0,0 +1,126 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef _TELEMETRY_H +#define _TELEMETRY_H + +/* Telemetry types */ +#define PMT_TELEM_TELEMETRY 0 +#define PMT_TELEM_CRASHLOG 1 + +struct telem_endpoint; +struct pci_dev; + +struct telem_header { + u8 access_type; + u16 size; + u32 guid; + u32 base_offset; +}; + +struct telem_endpoint_info { + struct pci_dev *pdev; + struct telem_header header; +}; + +/** + * pmt_telem_get_next_endpoint() - Get next device id for a telemetry endpoint + * @start: starting devid to look from + * + * This functions can be used in a while loop predicate to retrieve the devid + * of all available telemetry endpoints. Functions pmt_telem_get_next_endpoint() + * and pmt_telem_register_endpoint() can be used inside of the loop to examine + * endpoint info and register to receive a pointer to the endpoint. The pointer + * is then usable in the telemetry read calls to access the telemetry data. + * + * Return: + * * devid - devid of the next present endpoint from start + * * 0 - when no more endpoints are present after start + */ +unsigned long pmt_telem_get_next_endpoint(unsigned long start); + +/** + * pmt_telem_register_endpoint() - Register a telemetry endpoint + * @devid: device id/handle of the telemetry endpoint + * + * Increments the kref usage counter for the endpoint. + * + * Return: + * * endpoint - On success returns pointer to the telemetry endpoint + * * -ENXIO - telemetry endpoint not found + */ +struct telem_endpoint *pmt_telem_register_endpoint(int devid); + +/** + * pmt_telem_unregister_endpoint() - Unregister a telemetry endpoint + * @ep: ep structure to populate. + * + * Decrements the kref usage counter for the endpoint. + */ +void pmt_telem_unregister_endpoint(struct telem_endpoint *ep); + +/** + * pmt_telem_get_endpoint_info() - Get info for an endpoint from its devid + * @devid: device id/handle of the telemetry endpoint + * @info: Endpoint info structure to be populated + * + * Return: + * * 0 - Success + * * -ENXIO - telemetry endpoint not found for the devid + * * -EINVAL - @info is NULL + */ +int pmt_telem_get_endpoint_info(int devid, struct telem_endpoint_info *info); + +/** + * pmt_telem_find_and_register_endpoint() - Get a telemetry endpoint from + * pci_dev device, guid and pos + * @pdev: PCI device inside the Intel vsec + * @guid: GUID of the telemetry space + * @pos: Instance of the guid + * + * Return: + * * endpoint - On success returns pointer to the telemetry endpoint + * * -ENXIO - telemetry endpoint not found + */ +struct telem_endpoint *pmt_telem_find_and_register_endpoint(struct pci_dev *pcidev, + u32 guid, u16 pos); + +/** + * pmt_telem_read() - Read qwords from counter sram using sample id + * @ep: Telemetry endpoint to be read + * @id: The beginning sample id of the metric(s) to be read + * @data: Allocated qword buffer + * @count: Number of qwords requested + * + * Callers must ensure reads are aligned. When the call returns -ENODEV, + * the device has been removed and callers should unregister the telemetry + * endpoint. + * + * Return: + * * 0 - Success + * * -ENODEV - The device is not present. + * * -EINVAL - The offset is out bounds + * * -EPIPE - The device was removed during the read. Data written + * but should be considered invalid. + */ +int pmt_telem_read(struct telem_endpoint *ep, u32 id, u64 *data, u32 count); + +/** + * pmt_telem_read32() - Read qwords from counter sram using sample id + * @ep: Telemetry endpoint to be read + * @id: The beginning sample id of the metric(s) to be read + * @data: Allocated dword buffer + * @count: Number of dwords requested + * + * Callers must ensure reads are aligned. When the call returns -ENODEV, + * the device has been removed and callers should unregister the telemetry + * endpoint. + * + * Return: + * * 0 - Success + * * -ENODEV - The device is not present. + * * -EINVAL - The offset is out bounds + * * -EPIPE - The device was removed during the read. Data written + * but should be considered invalid. + */ +int pmt_telem_read32(struct telem_endpoint *ep, u32 id, u32 *data, u32 count); + +#endif