From patchwork Thu Mar 31 11:23:29 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Shannon Zhao X-Patchwork-Id: 64764 Delivered-To: patch@linaro.org Received: by 10.112.199.169 with SMTP id jl9csp95997lbc; Thu, 31 Mar 2016 04:26:25 -0700 (PDT) X-Received: by 10.66.249.228 with SMTP id yx4mr21204852pac.29.1459423578897; Thu, 31 Mar 2016 04:26:18 -0700 (PDT) Return-Path: Received: from vger.kernel.org (vger.kernel.org. [209.132.180.67]) by mx.google.com with ESMTP id yg4si1293096pab.161.2016.03.31.04.26.18; Thu, 31 Mar 2016 04:26:18 -0700 (PDT) Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67; Authentication-Results: mx.google.com; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756653AbcCaL0M (ORCPT + 29 others); Thu, 31 Mar 2016 07:26:12 -0400 Received: from szxga02-in.huawei.com ([119.145.14.65]:60215 "EHLO szxga02-in.huawei.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756307AbcCaLZR (ORCPT ); Thu, 31 Mar 2016 07:25:17 -0400 Received: from 172.24.1.51 (EHLO szxeml428-hub.china.huawei.com) ([172.24.1.51]) by szxrg02-dlp.huawei.com (MOS 4.3.7-GA FastPath queued) with ESMTP id DEL54425; Thu, 31 Mar 2016 19:24:59 +0800 (CST) Received: from HGHY1Z002260041.china.huawei.com (10.177.16.142) by szxeml428-hub.china.huawei.com (10.82.67.183) with Microsoft SMTP Server id 14.3.235.1; Thu, 31 Mar 2016 19:24:49 +0800 From: Shannon Zhao To: , , CC: , , , , , , , , , , "Rafael J. Wysocki" , "Len Brown" , "open list:ACPI" Subject: [PATCH v9 01/17] Xen: ACPI: Hide UART used by Xen Date: Thu, 31 Mar 2016 19:23:29 +0800 Message-ID: <1459423425-1220-2-git-send-email-zhaoshenglong@huawei.com> X-Mailer: git-send-email 1.9.0.msysgit.0 In-Reply-To: <1459423425-1220-1-git-send-email-zhaoshenglong@huawei.com> References: <1459423425-1220-1-git-send-email-zhaoshenglong@huawei.com> MIME-Version: 1.0 X-Originating-IP: [10.177.16.142] X-CFilter-Loop: Reflected X-Mirapoint-Virus-RAPID-Raw: score=unknown(0), refid=str=0001.0A0B0201.56FD090C.01AB, ss=1, re=0.000, recu=0.000, reip=0.000, cl=1, cld=1, fgs=0, ip=0.0.0.0, so=2013-06-18 04:22:30, dmn=2013-03-21 17:37:32 X-Mirapoint-Loop-Id: 8db51b03126ef1bad818cfaeb039f885 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Shannon Zhao ACPI 6.0 introduces a new table STAO to list the devices which are used by Xen and can't be used by Dom0. On Xen virtual platforms, the physical UART is used by Xen. So here it hides UART from Dom0. CC: "Rafael J. Wysocki" (supporter:ACPI) CC: Len Brown (supporter:ACPI) CC: linux-acpi@vger.kernel.org (open list:ACPI) Signed-off-by: Shannon Zhao --- drivers/acpi/scan.c | 69 +++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 69 insertions(+) -- 2.0.4 diff --git a/drivers/acpi/scan.c b/drivers/acpi/scan.c index 5f28cf7..29f26fc 100644 --- a/drivers/acpi/scan.c +++ b/drivers/acpi/scan.c @@ -45,6 +45,7 @@ static LIST_HEAD(acpi_scan_handlers_list); DEFINE_MUTEX(acpi_device_lock); LIST_HEAD(acpi_wakeup_device_list); static DEFINE_MUTEX(acpi_hp_context_lock); +static u64 spcr_uart_addr; struct acpi_dep_data { struct list_head node; @@ -1453,6 +1454,42 @@ static int acpi_add_single_object(struct acpi_device **child, return 0; } +static acpi_status acpi_get_resource_memory(struct acpi_resource *ares, + void *context) +{ + struct resource *res = context; + + if (acpi_dev_resource_memory(ares, res)) + return AE_CTRL_TERMINATE; + + return AE_OK; +} + +static bool acpi_device_should_be_hidden(acpi_handle handle) +{ + acpi_status status; + struct resource res; + + /* Check if it should ignore the UART device */ + if (spcr_uart_addr != 0) { + if (!acpi_has_method(handle, METHOD_NAME__CRS)) + return false; + + status = acpi_walk_resources(handle, METHOD_NAME__CRS, + acpi_get_resource_memory, &res); + if (ACPI_FAILURE(status)) + return false; + + if (res.start == spcr_uart_addr) { + printk(KERN_INFO PREFIX "The UART device @%pa in SPCR table will be hidden\n", + &res.start); + return true; + } + } + + return false; +} + static int acpi_bus_type_and_status(acpi_handle handle, int *type, unsigned long long *sta) { @@ -1466,6 +1503,9 @@ static int acpi_bus_type_and_status(acpi_handle handle, int *type, switch (acpi_type) { case ACPI_TYPE_ANY: /* for ACPI_ROOT_OBJECT */ case ACPI_TYPE_DEVICE: + if (acpi_device_should_be_hidden(handle)) + return -ENODEV; + *type = ACPI_BUS_TYPE_DEVICE; status = acpi_bus_get_status_handle(handle, sta); if (ACPI_FAILURE(status)) @@ -1916,9 +1956,24 @@ static int acpi_bus_scan_fixed(void) return result < 0 ? result : 0; } +static void __init acpi_get_spcr_uart_addr(void) +{ + acpi_status status; + struct acpi_table_spcr *spcr_ptr; + + status = acpi_get_table(ACPI_SIG_SPCR, 0, + (struct acpi_table_header **)&spcr_ptr); + if (ACPI_SUCCESS(status)) + spcr_uart_addr = spcr_ptr->serial_port.address; + else + printk(KERN_WARNING PREFIX "STAO table present, but SPCR is missing\n"); +} + int __init acpi_scan_init(void) { int result; + acpi_status status; + struct acpi_table_stao *stao_ptr; acpi_pci_root_init(); acpi_pci_link_init(); @@ -1934,6 +1989,20 @@ int __init acpi_scan_init(void) acpi_scan_add_handler(&generic_device_handler); + /* + * If there is STAO table, check whether it needs to ignore the UART + * device in SPCR table. + */ + status = acpi_get_table(ACPI_SIG_STAO, 0, + (struct acpi_table_header **)&stao_ptr); + if (ACPI_SUCCESS(status)) { + if (stao_ptr->header.length > sizeof(struct acpi_table_stao)) + printk(KERN_INFO PREFIX "STAO Name List not yet supported."); + + if (stao_ptr->ignore_uart) + acpi_get_spcr_uart_addr(); + } + mutex_lock(&acpi_scan_lock); /* * Enumerate devices in the ACPI namespace.