From patchwork Fri Feb 10 20:25:07 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Lukas Wunner X-Patchwork-Id: 13136410 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 079B6C636D4 for ; Fri, 10 Feb 2023 20:44:43 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233044AbjBJUom (ORCPT ); Fri, 10 Feb 2023 15:44:42 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:45824 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232935AbjBJUol (ORCPT ); Fri, 10 Feb 2023 15:44:41 -0500 Received: from mailout2.hostsharing.net (mailout2.hostsharing.net [83.223.78.233]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id B3C446FEA5; Fri, 10 Feb 2023 12:44:39 -0800 (PST) Received: from h08.hostsharing.net (h08.hostsharing.net [IPv6:2a01:37:1000::53df:5f1c:0]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256 client-signature RSA-PSS (4096 bits) client-digest SHA256) (Client CN "*.hostsharing.net", Issuer "RapidSSL Global TLS RSA4096 SHA256 2022 CA1" (verified OK)) by mailout2.hostsharing.net (Postfix) with ESMTPS id 09F1D10189E11; Fri, 10 Feb 2023 21:44:38 +0100 (CET) Received: from localhost (unknown [89.246.108.87]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange ECDHE (P-256) server-signature RSA-PSS (4096 bits) server-digest SHA256) (No client certificate requested) by h08.hostsharing.net (Postfix) with ESMTPSA id CC012600CA83; Fri, 10 Feb 2023 21:44:37 +0100 (CET) X-Mailbox-Line: From 5953272685cd245a400e5e0bd964573d9102eeb8 Mon Sep 17 00:00:00 2001 Message-Id: <5953272685cd245a400e5e0bd964573d9102eeb8.1676043318.git.lukas@wunner.de> In-Reply-To: References: From: Lukas Wunner Date: Fri, 10 Feb 2023 21:25:07 +0100 Subject: [PATCH v3 07/16] PCI/DOE: Provide synchronous API and use it internally To: Bjorn Helgaas , linux-pci@vger.kernel.org Cc: Gregory Price , Ira Weiny , Jonathan Cameron , Dan Williams , Alison Schofield , Vishal Verma , Dave Jiang , "Li, Ming" , Hillf Danton , Ben Widawsky , linuxarm@huawei.com, linux-cxl@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-cxl@vger.kernel.org The DOE API only allows asynchronous exchanges and forces callers to provide a completion callback. Yet all existing callers only perform synchronous exchanges. Upcoming commits for CMA (Component Measurement and Authentication, PCIe r6.0 sec 6.31) likewise require only synchronous DOE exchanges. Provide a synchronous pci_doe() API call which builds on the internal asynchronous machinery. Convert the internal pci_doe_discovery() to the new call. The new API allows submission of const-declared requests, necessitating the addition of a const qualifier in struct pci_doe_task. Tested-by: Ira Weiny Signed-off-by: Lukas Wunner Reviewed-by: Ira Weiny Reviewed-by: Jonathan Cameron Cc: Dan Williams Reviewed-by: Ming Li Reviewed-by: Davidlohr Bueso --- drivers/pci/doe.c | 69 ++++++++++++++++++++++++++++++++--------- include/linux/pci-doe.h | 6 +++- 2 files changed, 59 insertions(+), 16 deletions(-) diff --git a/drivers/pci/doe.c b/drivers/pci/doe.c index 6cf0600a38aa..d2edae8a32ac 100644 --- a/drivers/pci/doe.c +++ b/drivers/pci/doe.c @@ -319,28 +319,17 @@ static int pci_doe_discovery(struct pci_doe_mb *doe_mb, u8 *index, u16 *vid, u32 request_pl = FIELD_PREP(PCI_DOE_DATA_OBJECT_DISC_REQ_3_INDEX, *index); u32 response_pl; - DECLARE_COMPLETION_ONSTACK(c); - struct pci_doe_task task = { - .prot.vid = PCI_VENDOR_ID_PCI_SIG, - .prot.type = PCI_DOE_PROTOCOL_DISCOVERY, - .request_pl = (__le32 *)&request_pl, - .request_pl_sz = sizeof(request_pl), - .response_pl = (__le32 *)&response_pl, - .response_pl_sz = sizeof(response_pl), - .complete = pci_doe_task_complete, - .private = &c, - }; int rc; cpu_to_le32s(&request_pl); - rc = pci_doe_submit_task(doe_mb, &task); + rc = pci_doe(doe_mb, PCI_VENDOR_ID_PCI_SIG, PCI_DOE_PROTOCOL_DISCOVERY, + &request_pl, sizeof(request_pl), + &response_pl, sizeof(response_pl)); if (rc < 0) return rc; - wait_for_completion(&c); - - if (task.rv != sizeof(response_pl)) + if (rc != sizeof(response_pl)) return -EIO; le32_to_cpus(&response_pl); @@ -552,3 +541,53 @@ int pci_doe_submit_task(struct pci_doe_mb *doe_mb, struct pci_doe_task *task) return 0; } EXPORT_SYMBOL_GPL(pci_doe_submit_task); + +/** + * pci_doe() - Perform Data Object Exchange + * + * @doe_mb: DOE Mailbox + * @vendor: Vendor ID + * @type: Data Object Type + * @request: Request payload + * @request_sz: Size of request payload (bytes) + * @response: Response payload + * @response_sz: Size of response payload (bytes) + * + * Submit @request to @doe_mb and store the @response. + * The DOE exchange is performed synchronously and may therefore sleep. + * + * Payloads are treated as opaque byte streams which are transmitted verbatim, + * without byte-swapping. If payloads contain little-endian register values, + * the caller is responsible for conversion with cpu_to_le32() / le32_to_cpu(). + * + * RETURNS: Length of received response or negative errno. + * Received data in excess of @response_sz is discarded. + * The length may be smaller than @response_sz and the caller + * is responsible for checking that. + */ +int pci_doe(struct pci_doe_mb *doe_mb, u16 vendor, u8 type, + const void *request, size_t request_sz, + void *response, size_t response_sz) +{ + DECLARE_COMPLETION_ONSTACK(c); + struct pci_doe_task task = { + .prot.vid = vendor, + .prot.type = type, + .request_pl = request, + .request_pl_sz = request_sz, + .response_pl = response, + .response_pl_sz = response_sz, + .complete = pci_doe_task_complete, + .private = &c, + }; + int rc; + + rc = pci_doe_submit_task(doe_mb, &task); + if (rc) + return rc; + + wait_for_completion(&c); + + return task.rv; +} +EXPORT_SYMBOL_GPL(pci_doe); diff --git a/include/linux/pci-doe.h b/include/linux/pci-doe.h index 43765eaf2342..5dcd54f892e5 100644 --- a/include/linux/pci-doe.h +++ b/include/linux/pci-doe.h @@ -49,7 +49,7 @@ struct pci_doe_mb; */ struct pci_doe_task { struct pci_doe_protocol prot; - __le32 *request_pl; + const __le32 *request_pl; size_t request_pl_sz; __le32 *response_pl; size_t response_pl_sz; @@ -78,4 +78,8 @@ struct pci_doe_mb *pcim_doe_create_mb(struct pci_dev *pdev, u16 cap_offset); bool pci_doe_supports_prot(struct pci_doe_mb *doe_mb, u16 vid, u8 type); int pci_doe_submit_task(struct pci_doe_mb *doe_mb, struct pci_doe_task *task); +int pci_doe(struct pci_doe_mb *doe_mb, u16 vendor, u8 type, + const void *request, size_t request_sz, + void *response, size_t response_sz); + #endif