From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mga18.intel.com (mga18.intel.com [134.134.136.126]) by gabe.freedesktop.org (Postfix) with ESMTPS id 65E4210E522 for ; Wed, 23 Nov 2022 08:55:24 +0000 (UTC) From: Anshuman Gupta To: igt-dev@lists.freedesktop.org Date: Wed, 23 Nov 2022 14:24:37 +0530 Message-Id: <20221123085441.2821638-2-anshuman.gupta@intel.com> In-Reply-To: <20221123085441.2821638-1-anshuman.gupta@intel.com> References: <20221123085441.2821638-1-anshuman.gupta@intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=yes Content-Transfer-Encoding: 8bit Subject: [igt-dev] [PATCH i-g-t v3 1/5] lib/igt_pci: helpers to get PCI capabilities offset List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: badal.nilawar@intel.com, rodrigo.vivi@intel.com Errors-To: igt-dev-bounces@lists.freedesktop.org Sender: "igt-dev" List-ID: Added helper functions to search for PCI capabilities with help of libpciaccess library. Cc: Ashutosh Dixit Co-developed-by: Marcin Bernatowicz Signed-off-by: Marcin Bernatowicz Signed-off-by: Anshuman Gupta --- lib/igt_pci.c | 44 ++++++++++++++++++++++++++++++++++++++++++++ lib/igt_pci.h | 32 ++++++++++++++++++++++++++++++++ lib/meson.build | 1 + 3 files changed, 77 insertions(+) create mode 100644 lib/igt_pci.c create mode 100644 lib/igt_pci.h diff --git a/lib/igt_pci.c b/lib/igt_pci.c new file mode 100644 index 0000000000..bc0369341d --- /dev/null +++ b/lib/igt_pci.c @@ -0,0 +1,44 @@ +// SPDX-License-Identifier: MIT +/* + * Copyright © 2022 Intel Corporation + */ + +#include +#include "igt_pci.h" + +/** + * find_pci_cap_offset: + * @dev: pci device + * @cap_id: searched capability id, 0 means any capability + * @start_offset: offset in config space from which we start searching + * + * return: + * -1 on config read error, 0 if capability is not found, + * otherwise offset at which capability with cap_id is found + */ +int find_pci_cap_offset_at(struct pci_device *dev, enum pci_cap_id cap_id, + int start_offset) +{ + uint8_t offset; + uint16_t cap_header; + int loop = (PCI_CFG_SPACE_SIZE - PCI_TYPE0_1_HEADER_SIZE) + / sizeof(cap_header); + + if (pci_device_cfg_read_u8(dev, &offset, start_offset)) + return -1; + + while (loop--) { + if (offset < PCI_TYPE0_1_HEADER_SIZE) + break; + + if (pci_device_cfg_read_u16(dev, &cap_header, (offset & 0xFC))) + return -1; + + if (!cap_id || cap_id == (cap_header & 0xFF)) + return offset; + + offset = cap_header >> 8; + } + + return 0; +} diff --git a/lib/igt_pci.h b/lib/igt_pci.h new file mode 100644 index 0000000000..68afd2dacb --- /dev/null +++ b/lib/igt_pci.h @@ -0,0 +1,32 @@ +// SPDX-License-Identifier: MIT +/* + * Copyright © 2022 Intel Corporation + */ + +#ifndef __IGT_PCI_H__ +#define __IGT_PCI_H__ + +#include +#include + +/* forward declaration */ +struct pci_device; + +#define PCI_TYPE0_1_HEADER_SIZE 0x40 +#define PCI_CAPS_START 0x34 +#define PCI_CFG_SPACE_SIZE 0x100 +#define PCIE_CFG_SPACE_SIZE 0x1000 + +enum pci_cap_id { + PCI_EXPRESS_CAP_ID = 0x10 +}; + +int find_pci_cap_offset_at(struct pci_device *dev, enum pci_cap_id cap_id, + int start_offset); + +static inline int find_pci_cap_offset(struct pci_device *dev, enum pci_cap_id cap_id) +{ + return find_pci_cap_offset_at(dev, cap_id, PCI_CAPS_START); +} + +#endif diff --git a/lib/meson.build b/lib/meson.build index cef2d0ff3d..e0fb7ddfed 100644 --- a/lib/meson.build +++ b/lib/meson.build @@ -33,6 +33,7 @@ lib_sources = [ 'igt_pipe_crc.c', 'igt_power.c', 'igt_primes.c', + 'igt_pci.c', 'igt_rand.c', 'igt_stats.c', 'igt_syncobj.c', -- 2.25.1