From patchwork Fri Dec 6 12:56:04 2013 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Luis Henriques X-Patchwork-Id: 297858 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from huckleberry.canonical.com (huckleberry.canonical.com [91.189.94.19]) by ozlabs.org (Postfix) with ESMTP id 9142A2C0098 for ; Sat, 7 Dec 2013 00:07:41 +1100 (EST) Received: from localhost ([127.0.0.1] helo=huckleberry.canonical.com) by huckleberry.canonical.com with esmtp (Exim 4.76) (envelope-from ) id 1Vov84-0003Zm-6N; Fri, 06 Dec 2013 13:07:36 +0000 Received: from youngberry.canonical.com ([91.189.89.112]) by huckleberry.canonical.com with esmtp (Exim 4.76) (envelope-from ) id 1Vov1q-0007uK-30 for kernel-team@lists.ubuntu.com; Fri, 06 Dec 2013 13:01:10 +0000 Received: from bl20-223-32.dsl.telepac.pt ([2.81.223.32] helo=localhost) by youngberry.canonical.com with esmtpsa (TLS1.0:DHE_RSA_AES_128_CBC_SHA1:16) (Exim 4.71) (envelope-from ) id 1Vov1p-0007cD-Mg; Fri, 06 Dec 2013 13:01:10 +0000 From: Luis Henriques To: linux-kernel@vger.kernel.org, stable@vger.kernel.org, kernel-team@lists.ubuntu.com Subject: [PATCH 3.11 075/272] ARM: at91: fix hanged boot due to early rtt-interrupt Date: Fri, 6 Dec 2013 12:56:04 +0000 Message-Id: <1386334761-25517-76-git-send-email-luis.henriques@canonical.com> X-Mailer: git-send-email 1.8.3.2 In-Reply-To: <1386334761-25517-1-git-send-email-luis.henriques@canonical.com> References: <1386334761-25517-1-git-send-email-luis.henriques@canonical.com> X-Extended-Stable: 3.11 Cc: Johan Hovold , Nicolas Ferre X-BeenThere: kernel-team@lists.ubuntu.com X-Mailman-Version: 2.1.14 Precedence: list List-Id: Kernel team discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Errors-To: kernel-team-bounces@lists.ubuntu.com Sender: kernel-team-bounces@lists.ubuntu.com 3.11.10.1 -stable review patch. If anyone has any objections, please let me know. ------------------ From: Johan Hovold commit 94c4c79f2f1acca6e69a50bff5a7d9027509c16b upstream. Make sure the RTT-interrupts are masked at boot by adding a new helper function to be used at SOC-init. This fixes hanged boot on all AT91 SOCs with an RTT, for example, if an RTT-alarm goes off after a non-clean shutdown (e.g. when using RTC wakeup). The RTC and RTT-peripherals are powered by backup power (VDDBU) (on all AT91 SOCs but RM9200) and are not reset on wake-up, user, watchdog or software reset. This means that their interrupts may be enabled during early boot if, for example, they where not disabled during a previous shutdown (e.g. due to a buggy driver or a non-clean shutdown such as a user reset). Furthermore, an RTC or RTT-alarm may also be active. The RTC and RTT-interrupts use the shared system-interrupt line, which is also used by the PIT, and if an interrupt occurs before a handler (e.g. RTC-driver) has been installed this leads to the system interrupt being disabled and prevents the system from booting. Note that when boot hangs due to an early RTC or RTT-interrupt, the only way to get the system to start again is to remove the backup power (e.g. battery) or to disable the interrupt manually from the bootloader. In particular, a user reset is not sufficient. Signed-off-by: Johan Hovold Signed-off-by: Nicolas Ferre Signed-off-by: Luis Henriques --- arch/arm/mach-at91/at91sam9260.c | 2 ++ arch/arm/mach-at91/at91sam9261.c | 2 ++ arch/arm/mach-at91/at91sam9263.c | 3 +++ arch/arm/mach-at91/at91sam9g45.c | 1 + arch/arm/mach-at91/at91sam9rl.c | 1 + arch/arm/mach-at91/generic.h | 1 + arch/arm/mach-at91/sysirq_mask.c | 24 ++++++++++++++++++++++++ 7 files changed, 34 insertions(+) diff --git a/arch/arm/mach-at91/at91sam9260.c b/arch/arm/mach-at91/at91sam9260.c index 5de6074..ae10d14 100644 --- a/arch/arm/mach-at91/at91sam9260.c +++ b/arch/arm/mach-at91/at91sam9260.c @@ -349,6 +349,8 @@ static void __init at91sam9260_initialize(void) arm_pm_idle = at91sam9_idle; arm_pm_restart = at91sam9_alt_restart; + at91_sysirq_mask_rtt(AT91SAM9260_BASE_RTT); + /* Register GPIO subsystem */ at91_gpio_init(at91sam9260_gpio, 3); } diff --git a/arch/arm/mach-at91/at91sam9261.c b/arch/arm/mach-at91/at91sam9261.c index 0e07932..e761e74 100644 --- a/arch/arm/mach-at91/at91sam9261.c +++ b/arch/arm/mach-at91/at91sam9261.c @@ -291,6 +291,8 @@ static void __init at91sam9261_initialize(void) arm_pm_idle = at91sam9_idle; arm_pm_restart = at91sam9_alt_restart; + at91_sysirq_mask_rtt(AT91SAM9261_BASE_RTT); + /* Register GPIO subsystem */ at91_gpio_init(at91sam9261_gpio, 3); } diff --git a/arch/arm/mach-at91/at91sam9263.c b/arch/arm/mach-at91/at91sam9263.c index 6ce7d18..e6fed62 100644 --- a/arch/arm/mach-at91/at91sam9263.c +++ b/arch/arm/mach-at91/at91sam9263.c @@ -328,6 +328,9 @@ static void __init at91sam9263_initialize(void) arm_pm_idle = at91sam9_idle; arm_pm_restart = at91sam9_alt_restart; + at91_sysirq_mask_rtt(AT91SAM9263_BASE_RTT0); + at91_sysirq_mask_rtt(AT91SAM9263_BASE_RTT1); + /* Register GPIO subsystem */ at91_gpio_init(at91sam9263_gpio, 5); } diff --git a/arch/arm/mach-at91/at91sam9g45.c b/arch/arm/mach-at91/at91sam9g45.c index ff662af..9f7a97c 100644 --- a/arch/arm/mach-at91/at91sam9g45.c +++ b/arch/arm/mach-at91/at91sam9g45.c @@ -378,6 +378,7 @@ static void __init at91sam9g45_initialize(void) arm_pm_restart = at91sam9g45_restart; at91_sysirq_mask_rtc(AT91SAM9G45_BASE_RTC); + at91_sysirq_mask_rtt(AT91SAM9G45_BASE_RTT); /* Register GPIO subsystem */ at91_gpio_init(at91sam9g45_gpio, 5); diff --git a/arch/arm/mach-at91/at91sam9rl.c b/arch/arm/mach-at91/at91sam9rl.c index b5a8c9d..301e172 100644 --- a/arch/arm/mach-at91/at91sam9rl.c +++ b/arch/arm/mach-at91/at91sam9rl.c @@ -295,6 +295,7 @@ static void __init at91sam9rl_initialize(void) arm_pm_restart = at91sam9_alt_restart; at91_sysirq_mask_rtc(AT91SAM9RL_BASE_RTC); + at91_sysirq_mask_rtt(AT91SAM9RL_BASE_RTT); /* Register GPIO subsystem */ at91_gpio_init(at91sam9rl_gpio, 4); diff --git a/arch/arm/mach-at91/generic.h b/arch/arm/mach-at91/generic.h index 80269bd..26dee3c 100644 --- a/arch/arm/mach-at91/generic.h +++ b/arch/arm/mach-at91/generic.h @@ -35,6 +35,7 @@ extern int __init at91_aic_of_init(struct device_node *node, extern int __init at91_aic5_of_init(struct device_node *node, struct device_node *parent); extern void __init at91_sysirq_mask_rtc(u32 rtc_base); +extern void __init at91_sysirq_mask_rtt(u32 rtt_base); /* Timer */ diff --git a/arch/arm/mach-at91/sysirq_mask.c b/arch/arm/mach-at91/sysirq_mask.c index ee3e22c..2ba694f 100644 --- a/arch/arm/mach-at91/sysirq_mask.c +++ b/arch/arm/mach-at91/sysirq_mask.c @@ -21,6 +21,7 @@ */ #include +#include #include "generic.h" @@ -45,3 +46,26 @@ void __init at91_sysirq_mask_rtc(u32 rtc_base) iounmap(base); } + +void __init at91_sysirq_mask_rtt(u32 rtt_base) +{ + void __iomem *base; + void __iomem *reg; + u32 mode; + + base = ioremap(rtt_base, 16); + if (!base) + return; + + reg = base + AT91_RTT_MR; + + mode = readl_relaxed(reg); + if (mode & (AT91_RTT_ALMIEN | AT91_RTT_RTTINCIEN)) { + pr_info("AT91: Disabling rtt irq\n"); + mode &= ~(AT91_RTT_ALMIEN | AT91_RTT_RTTINCIEN); + writel_relaxed(mode, reg); + (void)readl_relaxed(reg); /* flush */ + } + + iounmap(base); +}