From patchwork Thu May 29 11:16:46 2025 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Badal Nilawar X-Patchwork-Id: 893131 Received: from mgamail.intel.com (mgamail.intel.com [192.198.163.8]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 7073628E573; Thu, 29 May 2025 11:14:56 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=192.198.163.8 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1748517298; cv=none; b=JGripuSm6+uhnK3Nb00R1gE7BHIo5bAEJi0zTTY97nYr4WlGMLuykuJtIHP74m0PjRkGj04Xm3EoLRuuvEOrv7o/U16B94n7fsCV37hEUUZuowvYeWkVUn0kUfnnpTgizramF5O8I5wUwdIivdE+51sY/w13tzZcu1/fXz4GHHk= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1748517298; c=relaxed/simple; bh=ekowM/ryMYQEdbGCtks8zg81DPHnG/+YlLbeuHfh8WA=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=Hm41SaE0SxO7jJg1wmxGK2cLxup/y+EjqotO8HJ5ifc8S+17zw2BWMAm4mwtOqojAONsU/Ueu/dct0y2RPbBiHwAskmbBqhrFe/evf3K8owiGD4rH7T8RfD8NrAqUmnvnxBWhrdSdR+uM/1BRU7TG4jG7rwVdvtj244Ib1qBq5I= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=intel.com; spf=pass smtp.mailfrom=intel.com; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b=kJ6oiy5O; arc=none smtp.client-ip=192.198.163.8 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=intel.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=intel.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b="kJ6oiy5O" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1748517296; x=1780053296; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=ekowM/ryMYQEdbGCtks8zg81DPHnG/+YlLbeuHfh8WA=; b=kJ6oiy5OzdHQQpskCczEyhBjMIm41VVJFjo5q96nEbotFgcgP74c5dv0 3K4nGIxBdHVO8iizsRUhTF0KaaCpQlRDRGFSjKc0YtyvUOI/pPF5Kca9c 94mfHkEMc7ctlALRKo4aE2hp2t9RwjOkZSvQeqFOnp7v8B24ohmEs0NIa 6OdVFGB2Nevi5SsfbhjDVgOP3NtXZwzVh7t3/pV8Fy8tnbFsa+92Td+3J PlEHNp8SF8PDFntJTml4+sZqegwkqGPXjaUNq0/LLrddREltv/942qfJI 3Ke+jW3FnAxuJo5OaSLrgJ5JVSpXXrY73t8t2IbSwVBlsuZ/xX8Jtdj97 Q==; X-CSE-ConnectionGUID: vHdet8MxQ4CWYYdcSCCP3g== X-CSE-MsgGUID: hioMDZP6Rai/t51KtB+LXQ== X-IronPort-AV: E=McAfee;i="6700,10204,11447"; a="68123118" X-IronPort-AV: E=Sophos;i="6.15,192,1739865600"; d="scan'208";a="68123118" Received: from fmviesa007.fm.intel.com ([10.60.135.147]) by fmvoesa102.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 29 May 2025 04:14:56 -0700 X-CSE-ConnectionGUID: Z/vn46dATBmKXVHPxzLfzw== X-CSE-MsgGUID: uxUc5E8dRkW9Pn7cCVhVag== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.15,192,1739865600"; d="scan'208";a="143510405" Received: from unknown (HELO bnilawar-desk2.iind.intel.com) ([10.190.239.41]) by fmviesa007-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 29 May 2025 04:14:53 -0700 From: Badal Nilawar To: intel-xe@lists.freedesktop.org, linux-acpi@vger.kernel.org, linux-pci@vger.kernel.org Cc: anshuman.gupta@intel.com, rafael@kernel.org, lenb@kernel.org, bhelgaas@google.com, ilpo.jarvinen@linux.intel.com, lucas.demarchi@intel.com, rodrigo.vivi@intel.com, varun.gupta@intel.com, ville.syrjala@linux.intel.com, uma.shankar@intel.com Subject: [PATCH v4 03/11] PCI/ACPI: Add PERST# Assertion Delay _DSM method Date: Thu, 29 May 2025 16:46:46 +0530 Message-Id: <20250529111654.3140766-4-badal.nilawar@intel.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20250529111654.3140766-1-badal.nilawar@intel.com> References: <20250529111654.3140766-1-badal.nilawar@intel.com> Precedence: bulk X-Mailing-List: linux-acpi@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 From: Anshuman Gupta Implement _DSM Method 0Bh as per PCI firmware specs section 4.6.11 Rev 3.3. Signed-off-by: Anshuman Gupta Signed-off-by: Badal Nilawar --- drivers/pci/pci-acpi.c | 57 ++++++++++++++++++++++++++++++++++++++++ include/linux/pci-acpi.h | 8 +++++- 2 files changed, 64 insertions(+), 1 deletion(-) diff --git a/drivers/pci/pci-acpi.c b/drivers/pci/pci-acpi.c index d33efba4ca94..88044491feaa 100644 --- a/drivers/pci/pci-acpi.c +++ b/drivers/pci/pci-acpi.c @@ -1531,6 +1531,63 @@ int pci_acpi_request_d3cold_aux_power(struct pci_dev *dev, u32 requested_power, } EXPORT_SYMBOL_GPL(pci_acpi_request_d3cold_aux_power); +/** + * pci_acpi_add_perst_assertion_delay - Request PERST# delay via ACPI DSM + * @dev: PCI device instance + * @delay_us: Requested delay_us + * + * This function sends a request to the host BIOS via ACPI _DSM to grant the + * required PERST# delay for the specified PCI device. It evaluates the _DSM + * to request the PERST# delay and handles the response accordingly. + * + * Return: returns 0 on success and errno on failure. + */ +int pci_acpi_add_perst_assertion_delay(struct pci_dev *dev, u32 delay_us) +{ + union acpi_object in_obj = { + .integer.type = ACPI_TYPE_INTEGER, + .integer.value = delay_us, + }; + + union acpi_object *out_obj; + acpi_handle handle; + int result, ret = -EINVAL; + + if (!dev) + return -EINVAL; + + handle = ACPI_HANDLE(&dev->dev); + if (!handle) + return -EINVAL; + + if (!acpi_check_dsm(handle, &pci_acpi_dsm_guid, 4, 1 << DSM_PCI_PERST_ASSERTION_DELAY)) { + pci_dbg(dev, "ACPI _DSM 0%Xh not supported\n", DSM_PCI_PERST_ASSERTION_DELAY); + return -ENODEV; + } + + out_obj = acpi_evaluate_dsm_typed(handle, &pci_acpi_dsm_guid, 4, + DSM_PCI_PERST_ASSERTION_DELAY, + &in_obj, ACPI_TYPE_INTEGER); + if (!out_obj) + return -EINVAL; + + result = out_obj->integer.value; + + if (result == delay_us) { + pci_info(dev, "PERST# Assertion Delay set to %u microseconds\n", delay_us); + ret = 0; + } else if (result == 0) { + pci_warn(dev, "PERST# Assertion Delay request failed, no previous valid request\n"); + } else { + pci_warn(dev, "PERST# Assertion Delay request failed, Previous valid delay: %u microseconds\n", + result); + } + + ACPI_FREE(out_obj); + return ret; +} +EXPORT_SYMBOL_GPL(pci_acpi_add_perst_assertion_delay); + static void pci_acpi_set_external_facing(struct pci_dev *dev) { u8 val; diff --git a/include/linux/pci-acpi.h b/include/linux/pci-acpi.h index 6079306ad754..e53d4893cf56 100644 --- a/include/linux/pci-acpi.h +++ b/include/linux/pci-acpi.h @@ -122,6 +122,7 @@ extern const guid_t pci_acpi_dsm_guid; #define DSM_PCI_POWER_ON_RESET_DELAY 0x08 #define DSM_PCI_DEVICE_READINESS_DURATIONS 0x09 #define DSM_PCI_D3COLD_AUX_POWER_LIMIT 0x0A +#define DSM_PCI_PERST_ASSERTION_DELAY 0x0B #ifdef CONFIG_PCIE_EDR void pci_acpi_add_edr_notifier(struct pci_dev *pdev); @@ -135,7 +136,7 @@ int pci_acpi_set_companion_lookup_hook(struct acpi_device *(*func)(struct pci_de void pci_acpi_clear_companion_lookup_hook(void); int pci_acpi_request_d3cold_aux_power(struct pci_dev *dev, u32 requested_power, u32 *retry_interval); - +int pci_acpi_add_perst_assertion_delay(struct pci_dev *dev, u32 delay_us); #else /* CONFIG_ACPI */ static inline void acpi_pci_add_bus(struct pci_bus *bus) { } static inline void acpi_pci_remove_bus(struct pci_bus *bus) { } @@ -144,6 +145,11 @@ static inline int pci_acpi_request_d3cold_aux_power(struct pci_dev *dev, u32 req { return -EOPNOTSUPP; } + +static inline int pci_acpi_add_perst_assertion_delay(struct pci_dev *dev, u32 delay_us) +{ + return -EOPNOTSUPP; +} #endif /* CONFIG_ACPI */ #endif /* _PCI_ACPI_H_ */