From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753195AbbCGXQO (ORCPT ); Sat, 7 Mar 2015 18:16:14 -0500 Received: from mail-wi0-f171.google.com ([209.85.212.171]:37358 "EHLO mail-wi0-f171.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753000AbbCGXQM (ORCPT ); Sat, 7 Mar 2015 18:16:12 -0500 From: Grant Likely Subject: Re: [PATCH v9 17/21] clocksource / arch_timer: Parse GTDT to initialize arch timer To: Hanjun Guo , Catalin Marinas , "Rafael J. Wysocki" , Will Deacon , Olof Johansson Cc: Lorenzo Pieralisi , Arnd Bergmann , Mark Rutland , Graeme Gregory , Sudeep Holla , Jon Masters , Marc Zyngier , Mark Brown , Robert Richter , Timur Tabi , Ashwin Chaugule , suravee.suthikulpanit@amd.com, linux-acpi@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, linaro-acpi@lists.linaro.org, Hanjun Guo , Daniel Lezcano , Thomas Gleixner In-Reply-To: <1424853601-6675-18-git-send-email-hanjun.guo@linaro.org> References: <1424853601-6675-1-git-send-email-hanjun.guo@linaro.org> <1424853601-6675-18-git-send-email-hanjun.guo@linaro.org> Date: Sat, 07 Mar 2015 23:16:07 +0000 Message-Id: <20150307231607.73044C40C6A@trevor.secretlab.ca> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, 25 Feb 2015 16:39:57 +0800 , Hanjun Guo wrote: > Using the information presented by GTDT (Generic Timer Description Table) > to initialize the arch timer (not memory-mapped). > > CC: Daniel Lezcano > CC: Thomas Gleixner > Originally-by: Amit Daniel Kachhap > Tested-by: Suravee Suthikulpanit > Tested-by: Yijing Wang > Tested-by: Mark Langsdorf > Tested-by: Jon Masters > Tested-by: Timur Tabi > Tested-by: Robert Richter > Acked-by: Robert Richter > Signed-off-by: Hanjun Guo Reviewed-by: Grant Likely > --- > arch/arm64/kernel/time.c | 7 ++ > drivers/clocksource/arm_arch_timer.c | 132 ++++++++++++++++++++++++++++------- > include/linux/clocksource.h | 6 ++ > 3 files changed, 118 insertions(+), 27 deletions(-) > > diff --git a/arch/arm64/kernel/time.c b/arch/arm64/kernel/time.c > index 1a7125c..42f9195 100644 > --- a/arch/arm64/kernel/time.c > +++ b/arch/arm64/kernel/time.c > @@ -35,6 +35,7 @@ > #include > #include > #include > +#include > > #include > > @@ -72,6 +73,12 @@ void __init time_init(void) > > tick_setup_hrtimer_broadcast(); > > + /* > + * Since ACPI or FDT will only one be available in the system, > + * we can use acpi_generic_timer_init() here safely > + */ > + acpi_generic_timer_init(); > + > arch_timer_rate = arch_timer_get_rate(); > if (!arch_timer_rate) > panic("Unable to initialise architected timer.\n"); > diff --git a/drivers/clocksource/arm_arch_timer.c b/drivers/clocksource/arm_arch_timer.c > index a3025e7..ea62fc7 100644 > --- a/drivers/clocksource/arm_arch_timer.c > +++ b/drivers/clocksource/arm_arch_timer.c > @@ -22,6 +22,7 @@ > #include > #include > #include > +#include > > #include > #include > @@ -371,8 +372,12 @@ arch_timer_detect_rate(void __iomem *cntbase, struct device_node *np) > if (arch_timer_rate) > return; > > - /* Try to determine the frequency from the device tree or CNTFRQ */ > - if (of_property_read_u32(np, "clock-frequency", &arch_timer_rate)) { > + /* > + * Try to determine the frequency from the device tree or CNTFRQ, > + * if ACPI is enabled, get the frequency from CNTFRQ ONLY. > + */ > + if (!acpi_disabled || > + of_property_read_u32(np, "clock-frequency", &arch_timer_rate)) { > if (cntbase) > arch_timer_rate = readl_relaxed(cntbase + CNTFRQ); > else > @@ -691,28 +696,8 @@ static void __init arch_timer_common_init(void) > arch_timer_arch_init(); > } > > -static void __init arch_timer_init(struct device_node *np) > +static void __init arch_timer_init(void) > { > - int i; > - > - if (arch_timers_present & ARCH_CP15_TIMER) { > - pr_warn("arch_timer: multiple nodes in dt, skipping\n"); > - return; > - } > - > - arch_timers_present |= ARCH_CP15_TIMER; > - for (i = PHYS_SECURE_PPI; i < MAX_TIMER_PPI; i++) > - arch_timer_ppi[i] = irq_of_parse_and_map(np, i); > - arch_timer_detect_rate(NULL, np); > - > - /* > - * If we cannot rely on firmware initializing the timer registers then > - * we should use the physical timers instead. > - */ > - if (IS_ENABLED(CONFIG_ARM) && > - of_property_read_bool(np, "arm,cpu-registers-not-fw-configured")) > - arch_timer_use_virtual = false; > - > /* > * If HYP mode is available, we know that the physical timer > * has been configured to be accessible from PL1. Use it, so > @@ -731,13 +716,39 @@ static void __init arch_timer_init(struct device_node *np) > } > } > > - arch_timer_c3stop = !of_property_read_bool(np, "always-on"); > - > arch_timer_register(); > arch_timer_common_init(); > } > -CLOCKSOURCE_OF_DECLARE(armv7_arch_timer, "arm,armv7-timer", arch_timer_init); > -CLOCKSOURCE_OF_DECLARE(armv8_arch_timer, "arm,armv8-timer", arch_timer_init); > + > +static void __init arch_timer_of_init(struct device_node *np) > +{ > + int i; > + > + if (arch_timers_present & ARCH_CP15_TIMER) { > + pr_warn("arch_timer: multiple nodes in dt, skipping\n"); > + return; > + } > + > + arch_timers_present |= ARCH_CP15_TIMER; > + for (i = PHYS_SECURE_PPI; i < MAX_TIMER_PPI; i++) > + arch_timer_ppi[i] = irq_of_parse_and_map(np, i); > + > + arch_timer_detect_rate(NULL, np); > + > + arch_timer_c3stop = !of_property_read_bool(np, "always-on"); > + > + /* > + * If we cannot rely on firmware initializing the timer registers then > + * we should use the physical timers instead. > + */ > + if (IS_ENABLED(CONFIG_ARM) && > + of_property_read_bool(np, "arm,cpu-registers-not-fw-configured")) > + arch_timer_use_virtual = false; > + > + arch_timer_init(); > +} > +CLOCKSOURCE_OF_DECLARE(armv7_arch_timer, "arm,armv7-timer", arch_timer_of_init); > +CLOCKSOURCE_OF_DECLARE(armv8_arch_timer, "arm,armv8-timer", arch_timer_of_init); > > static void __init arch_timer_mem_init(struct device_node *np) > { > @@ -804,3 +815,70 @@ static void __init arch_timer_mem_init(struct device_node *np) > } > CLOCKSOURCE_OF_DECLARE(armv7_arch_timer_mem, "arm,armv7-timer-mem", > arch_timer_mem_init); > + > +#ifdef CONFIG_ACPI > +static int __init map_generic_timer_interrupt(u32 interrupt, u32 flags) > +{ > + int trigger, polarity; > + > + if (!interrupt) > + return 0; > + > + trigger = (flags & ACPI_GTDT_INTERRUPT_MODE) ? ACPI_EDGE_SENSITIVE > + : ACPI_LEVEL_SENSITIVE; > + > + polarity = (flags & ACPI_GTDT_INTERRUPT_POLARITY) ? ACPI_ACTIVE_LOW > + : ACPI_ACTIVE_HIGH; > + > + return acpi_register_gsi(NULL, interrupt, trigger, polarity); > +} > + > +/* Initialize per-processor generic timer */ > +static int __init arch_timer_acpi_init(struct acpi_table_header *table) > +{ > + struct acpi_table_gtdt *gtdt; > + > + if (arch_timers_present & ARCH_CP15_TIMER) { > + pr_warn("arch_timer: already initialized, skipping\n"); > + return -EINVAL; > + } > + > + gtdt = container_of(table, struct acpi_table_gtdt, header); > + > + arch_timers_present |= ARCH_CP15_TIMER; > + > + arch_timer_ppi[PHYS_SECURE_PPI] = > + map_generic_timer_interrupt(gtdt->secure_el1_interrupt, > + gtdt->secure_el1_flags); > + > + arch_timer_ppi[PHYS_NONSECURE_PPI] = > + map_generic_timer_interrupt(gtdt->non_secure_el1_interrupt, > + gtdt->non_secure_el1_flags); > + > + arch_timer_ppi[VIRT_PPI] = > + map_generic_timer_interrupt(gtdt->virtual_timer_interrupt, > + gtdt->virtual_timer_flags); > + > + arch_timer_ppi[HYP_PPI] = > + map_generic_timer_interrupt(gtdt->non_secure_el2_interrupt, > + gtdt->non_secure_el2_flags); > + > + /* Get the frequency from CNTFRQ */ > + arch_timer_detect_rate(NULL, NULL); > + > + /* Always-on capability */ > + arch_timer_c3stop = !(gtdt->non_secure_el1_flags & ACPI_GTDT_ALWAYS_ON); > + > + arch_timer_init(); > + return 0; > +} > + > +/* Initialize all the generic timers presented in GTDT */ > +void __init acpi_generic_timer_init(void) > +{ > + if (acpi_disabled) > + return; > + > + acpi_table_parse(ACPI_SIG_GTDT, arch_timer_acpi_init); > +} > +#endif > diff --git a/include/linux/clocksource.h b/include/linux/clocksource.h > index 9c78d15..2b2e1f8 100644 > --- a/include/linux/clocksource.h > +++ b/include/linux/clocksource.h > @@ -244,4 +244,10 @@ extern void clocksource_of_init(void); > static inline void clocksource_of_init(void) {} > #endif > > +#ifdef CONFIG_ACPI > +void acpi_generic_timer_init(void); > +#else > +static inline void acpi_generic_timer_init(void) { } > +#endif > + > #endif /* _LINUX_CLOCKSOURCE_H */ > -- > 1.9.1 >