From patchwork Wed Apr 19 16:44:33 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Mark Rutland X-Patchwork-Id: 97657 Delivered-To: patch@linaro.org Received: by 10.182.246.10 with SMTP id xs10csp355396obc; Wed, 19 Apr 2017 09:46:50 -0700 (PDT) X-Received: by 10.98.92.1 with SMTP id q1mr3914112pfb.209.1492620410905; Wed, 19 Apr 2017 09:46:50 -0700 (PDT) Return-Path: Received: from vger.kernel.org (vger.kernel.org. [209.132.180.67]) by mx.google.com with ESMTP id b6si3257098pfa.364.2017.04.19.09.46.50; Wed, 19 Apr 2017 09:46:50 -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 S966790AbdDSQqT (ORCPT + 16 others); Wed, 19 Apr 2017 12:46:19 -0400 Received: from foss.arm.com ([217.140.101.70]:43762 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S966533AbdDSQpt (ORCPT ); Wed, 19 Apr 2017 12:45:49 -0400 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.72.51.249]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id EBDBC16A3; Wed, 19 Apr 2017 09:45:38 -0700 (PDT) Received: from leverpostej.cambridge.arm.com (usa-sjc-imap-foss1.foss.arm.com [10.72.51.249]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id 82C473F4FF; Wed, 19 Apr 2017 09:45:37 -0700 (PDT) From: Mark Rutland To: daniel.lezcano@linaro.org Cc: linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, tglx@linutronix.de, fu.wei@linaro.org, lorenzo.pieralisi@arm.com, hanjun.guo@linaro.org, marc.zyngier@arm.com Subject: [PATCH 16/16] acpi/arm64: Add SBSA Generic Watchdog support in GTDT driver Date: Wed, 19 Apr 2017 17:44:33 +0100 Message-Id: <1492620273-30037-17-git-send-email-mark.rutland@arm.com> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1492620273-30037-1-git-send-email-mark.rutland@arm.com> References: <1492620273-30037-1-git-send-email-mark.rutland@arm.com> MIME-Version: 1.0 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Fu Wei This driver adds support for parsing SBSA Generic Watchdog timer in GTDT, parse all info in SBSA Generic Watchdog Structure in GTDT, and creating a platform device with that information. This allows the operating system to obtain device data from the resource of platform device. The platform device named "sbsa-gwdt" can be used by the ARM SBSA Generic Watchdog driver. Signed-off-by: Fu Wei Signed-off-by: Hanjun Guo Tested-by: Xiongfeng Wang Reviewed-by: Lorenzo Pieralisi Signed-off-by: Mark Rutland --- drivers/acpi/arm64/gtdt.c | 103 ++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 103 insertions(+) -- 1.9.1 diff --git a/drivers/acpi/arm64/gtdt.c b/drivers/acpi/arm64/gtdt.c index b904667..597a737 100644 --- a/drivers/acpi/arm64/gtdt.c +++ b/drivers/acpi/arm64/gtdt.c @@ -15,6 +15,7 @@ #include #include #include +#include #include @@ -60,6 +61,17 @@ static inline bool is_timer_block(void *platform_timer) return gh->type == ACPI_GTDT_TYPE_TIMER_BLOCK; } +static inline bool is_non_secure_watchdog(void *platform_timer) +{ + struct acpi_gtdt_header *gh = platform_timer; + struct acpi_gtdt_watchdog *wd = platform_timer; + + if (gh->type != ACPI_GTDT_TYPE_WATCHDOG) + return false; + + return !(wd->timer_flags & ACPI_GTDT_WATCHDOG_SECURE); +} + static int __init map_gt_gsi(u32 interrupt, u32 flags) { int trigger, polarity; @@ -312,3 +324,94 @@ int __init acpi_arch_timer_mem_init(struct arch_timer_mem *timer_mem, return 0; } + +/* + * Initialize a SBSA generic Watchdog platform device info from GTDT + */ +static int __init gtdt_import_sbsa_gwdt(struct acpi_gtdt_watchdog *wd, + int index) +{ + struct platform_device *pdev; + int irq = map_gt_gsi(wd->timer_interrupt, wd->timer_flags); + + /* + * According to SBSA specification the size of refresh and control + * frames of SBSA Generic Watchdog is SZ_4K(Offset 0x000 – 0xFFF). + */ + struct resource res[] = { + DEFINE_RES_MEM(wd->control_frame_address, SZ_4K), + DEFINE_RES_MEM(wd->refresh_frame_address, SZ_4K), + DEFINE_RES_IRQ(irq), + }; + int nr_res = ARRAY_SIZE(res); + + pr_debug("found a Watchdog (0x%llx/0x%llx gsi:%u flags:0x%x).\n", + wd->refresh_frame_address, wd->control_frame_address, + wd->timer_interrupt, wd->timer_flags); + + if (!(wd->refresh_frame_address && wd->control_frame_address)) { + pr_err(FW_BUG "failed to get the Watchdog base address.\n"); + acpi_unregister_gsi(wd->timer_interrupt); + return -EINVAL; + } + + if (irq <= 0) { + pr_warn("failed to map the Watchdog interrupt.\n"); + nr_res--; + } + + /* + * Add a platform device named "sbsa-gwdt" to match the platform driver. + * "sbsa-gwdt": SBSA(Server Base System Architecture) Generic Watchdog + * The platform driver can get device info below by matching this name. + */ + pdev = platform_device_register_simple("sbsa-gwdt", index, res, nr_res); + if (IS_ERR(pdev)) { + acpi_unregister_gsi(wd->timer_interrupt); + return PTR_ERR(pdev); + } + + return 0; +} + +static int __init gtdt_sbsa_gwdt_init(void) +{ + void *platform_timer; + struct acpi_table_header *table; + int ret, timer_count, gwdt_count = 0; + + if (acpi_disabled) + return 0; + + if (ACPI_FAILURE(acpi_get_table(ACPI_SIG_GTDT, 0, &table))) + return -EINVAL; + + /* + * Note: Even though the global variable acpi_gtdt_desc has been + * initialized by acpi_gtdt_init() while initializing the arch timers, + * when we call this function to get SBSA watchdogs info from GTDT, the + * pointers stashed in it are stale (since they are early temporary + * mappings carried out before acpi_permanent_mmap is set) and we need + * to re-initialize them with permanent mapped pointer values to let the + * GTDT parsing possible. + */ + ret = acpi_gtdt_init(table, &timer_count); + if (ret || !timer_count) + return ret; + + for_each_platform_timer(platform_timer) { + if (is_non_secure_watchdog(platform_timer)) { + ret = gtdt_import_sbsa_gwdt(platform_timer, gwdt_count); + if (ret) + break; + gwdt_count++; + } + } + + if (gwdt_count) + pr_info("found %d SBSA generic Watchdog(s).\n", gwdt_count); + + return ret; +} + +device_initcall(gtdt_sbsa_gwdt_init);