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Donenfeld" , Richard Henderson , linux-alpha@vger.kernel.org, Russell King , linux-arm-kernel@lists.infradead.org, Catalin Marinas , Huacai Chen , loongarch@lists.linux.dev, Geert Uytterhoeven , linux-m68k@lists.linux-m68k.org, Dinh Nguyen , Jonas Bonn , linux-openrisc@vger.kernel.org, Helge Deller , linux-parisc@vger.kernel.org, Michael Ellerman , linuxppc-dev@lists.ozlabs.org, Paul Walmsley , linux-riscv@lists.infradead.org, Heiko Carstens , linux-s390@vger.kernel.org, "David S. Miller" , sparclinux@vger.kernel.org, "linux-tegra@vger.kernel.org" References: <20260410120044.031381086@kernel.org> <20260410120317.978403520@kernel.org> Content-Language: en-US From: Jon Hunter In-Reply-To: <20260410120317.978403520@kernel.org> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-ClientProxiedBy: FR0P281CA0205.DEUP281.PROD.OUTLOOK.COM (2603:10a6:d10:ad::19) To SJ1PR12MB6051.namprd12.prod.outlook.com (2603:10b6:a03:48a::18) Precedence: bulk X-Mailing-List: linux-parisc@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-MS-PublicTrafficType: Email X-MS-TrafficTypeDiagnostic: SJ1PR12MB6051:EE_|DS7PR12MB5936:EE_ X-MS-Office365-Filtering-Correlation-Id: 403b744e-fd37-478d-d403-08defed5dea4 X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0;ARA:13230040|376014|7416014|1800799024|23010399003|366016|10067099003|11063799006|4143699003|56012099006|18002099003|22082099003; X-Microsoft-Antispam-Message-Info: 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 X-Forefront-Antispam-Report: CIP:255.255.255.255;CTRY:;LANG:en;SCL:1;SRV:;IPV:NLI;SFV:NSPM;H:SJ1PR12MB6051.namprd12.prod.outlook.com;PTR:;CAT:NONE;SFS:(13230040)(376014)(7416014)(1800799024)(23010399003)(366016)(10067099003)(11063799006)(4143699003)(56012099006)(18002099003)(22082099003);DIR:OUT;SFP:1101; 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Move the declaration to linux/delay.h where it > belongs. > > Remove the resulting empty asm/timex.h files as well. > > No functional change. > > Signed-off-by: Thomas Gleixner > Cc: Arnd Bergmann ... > --- a/arch/arm/include/asm/timex.h > +++ b/arch/arm/include/asm/timex.h > @@ -10,7 +10,10 @@ > #define _ASMARM_TIMEX_H > > typedef unsigned long cycles_t; > -#define get_cycles() ({ cycles_t c; read_current_timer(&c) ? 0 : c; }) > +// Temporary workaround > +bool delay_read_timer(unsigned long *t); > + > +#define get_cycles() ({ cycles_t c; delay_read_timer(&c) ? 0 : c; }) > #define random_get_entropy() (((unsigned long)get_cycles()) ?: random_get_entropy_fallback()) I have noticed a boot regression on some of our 32-bit Tegra platforms. Bisect is pointing to this commit. Making the following change does fix it, as delay_read_timer() now returns a valid value when true ... diff --git a/arch/arm/include/asm/timex.h b/arch/arm/include/asm/timex.h index 94e40c19cfc5..4d31eab9dba2 100644 --- a/arch/arm/include/asm/timex.h +++ b/arch/arm/include/asm/timex.h @@ -13,7 +13,7 @@ typedef unsigned long cycles_t; // Temporary workaround until timex.h is cleaned up bool delay_read_timer(unsigned long *t); -#define get_cycles() ({ cycles_t c; delay_read_timer(&c) ? 0 : c; }) +#define get_cycles() ({ cycles_t c; delay_read_timer(&c) ? c : 0; }) #define random_get_entropy() (((unsigned long)get_cycles()) ?: random_get_entropy_fallback()) Cheers Jon -- nvpublic