From mboxrd@z Thu Jan 1 00:00:00 1970 From: Stefano Stabellini Subject: Re: [PATCH v4 17/21] arm/acpi: Parse GTDT to initialize timer Date: Tue, 2 Feb 2016 17:45:06 +0000 Message-ID: References: <1453540813-15764-1-git-send-email-zhaoshenglong@huawei.com> <1453540813-15764-18-git-send-email-zhaoshenglong@huawei.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <1453540813-15764-18-git-send-email-zhaoshenglong@huawei.com> List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xen.org Errors-To: xen-devel-bounces@lists.xen.org To: Shannon Zhao Cc: ian.campbell@citrix.com, stefano.stabellini@eu.citrix.com, peter.huangpeng@huawei.com, xen-devel@lists.xen.org, julien.grall@citrix.com, stefano.stabellini@citrix.com, shannon.zhao@linaro.org List-Id: xen-devel@lists.xenproject.org On Sat, 23 Jan 2016, Shannon Zhao wrote: > From: Shannon Zhao > > Parse GTDT (Generic Timer Descriptor Table) to initialize timer. Using > the information presented by GTDT to initialize the arch timer (not > memory-mapped). > > Signed-off-by: Parth Dixit > Signed-off-by: Shannon Zhao > --- > V4: Factor dt parts > --- > xen/arch/arm/time.c | 82 ++++++++++++++++++++++++++++++++++++++++++++--------- > 1 file changed, 68 insertions(+), 14 deletions(-) > > diff --git a/xen/arch/arm/time.c b/xen/arch/arm/time.c > index 73a1a3e..4261207 100644 > --- a/xen/arch/arm/time.c > +++ b/xen/arch/arm/time.c > @@ -29,6 +29,7 @@ > #include > #include > #include > +#include > #include > #include > #include > @@ -65,8 +66,52 @@ unsigned int timer_get_irq(enum timer_ppi ppi) > > static __initdata struct dt_device_node *timer; > > +#ifdef CONFIG_ACPI > +static u32 __init acpi_get_timer_irq_type(u32 flags) > +{ > + return (flags & ACPI_GTDT_INTERRUPT_MODE) ? IRQ_TYPE_EDGE_BOTH > + : IRQ_TYPE_LEVEL_MASK; > +} > + > +/* Initialize per-processor generic timer */ > +static int __init arch_timer_acpi_init(struct acpi_table_header *header) > +{ > + u32 irq_type; > + struct acpi_table_gtdt *gtdt; > + > + gtdt = container_of(header, struct acpi_table_gtdt, header); > + > + /* Initialize all the generic timer IRQ variable from GTDT table */ > + irq_type = acpi_get_timer_irq_type(gtdt->non_secure_el1_flags); > + irq_set_type(gtdt->non_secure_el1_interrupt, irq_type); > + timer_irq[TIMER_PHYS_NONSECURE_PPI] = gtdt->non_secure_el1_interrupt; > + > + irq_type = acpi_get_timer_irq_type(gtdt->secure_el1_flags); > + irq_set_type(gtdt->secure_el1_interrupt, irq_type); > + timer_irq[TIMER_PHYS_SECURE_PPI] = gtdt->secure_el1_interrupt; > + > + irq_type = acpi_get_timer_irq_type(gtdt->virtual_timer_flags); > + irq_set_type(gtdt->virtual_timer_interrupt, irq_type); > + timer_irq[TIMER_VIRT_PPI] = gtdt->virtual_timer_interrupt; > + > + irq_type = acpi_get_timer_irq_type(gtdt->non_secure_el2_flags); > + irq_set_type(gtdt->non_secure_el2_interrupt, irq_type); > + timer_irq[TIMER_HYP_PPI] = gtdt->non_secure_el2_interrupt; > + > + return 0; > +} > + > +static void __init preinit_acpi_xen_time(void) > +{ > + acpi_table_parse(ACPI_SIG_GTDT, arch_timer_acpi_init); > + cpu_khz = READ_SYSREG32(CNTFRQ_EL0) / 1000; I would move this and the other line like this in preinit_dt_xen_time to preinit_xen_time, with a if (!cpu_khz) check. > +} > +#else > +static inline void preinit_acpi_xen_time(void) { } > +#endif As usual, this can go away. Everything else is good. > /* Set up the timer on the boot CPU (early init function) */ > -void __init preinit_xen_time(void) > +static void __init preinit_dt_xen_time(void) > { > static const struct dt_device_match timer_ids[] __initconst = > { > @@ -75,6 +120,7 @@ void __init preinit_xen_time(void) > }; > int res; > u32 rate; > + unsigned int i; > > timer = dt_find_matching_node(NULL, timer_ids); > if ( !timer ) > @@ -82,10 +128,6 @@ void __init preinit_xen_time(void) > > dt_device_set_used_by(timer, DOMID_XEN); > > - res = platform_init_time(); > - if ( res ) > - panic("Timer: Cannot initialize platform timer"); > - > res = dt_property_read_u32(timer, "clock-frequency", &rate); > if ( res ) > { > @@ -95,15 +137,6 @@ void __init preinit_xen_time(void) > else > cpu_khz = READ_SYSREG32(CNTFRQ_EL0) / 1000; > > - boot_count = READ_SYSREG64(CNTPCT_EL0); > -} > - > -/* Set up the timer on the boot CPU (late init function) */ > -int __init init_xen_time(void) > -{ > - int res; > - unsigned int i; > - > /* Retrieve all IRQs for the timer */ > for ( i = TIMER_PHYS_SECURE_PPI; i < MAX_TIMER_PPI; i++ ) > { > @@ -113,7 +146,28 @@ int __init init_xen_time(void) > panic("Timer: Unable to retrieve IRQ %u from the device tree", i); > timer_irq[i] = res; > } > +} > + > +void __init preinit_xen_time(void) > +{ > + int res; > > + /* Initialize all the generic timers presented in GTDT */ > + if ( acpi_disabled ) > + preinit_dt_xen_time(); > + else > + preinit_acpi_xen_time(); > + > + res = platform_init_time(); > + if ( res ) > + panic("Timer: Cannot initialize platform timer"); > + > + boot_count = READ_SYSREG64(CNTPCT_EL0); > +} > + > +/* Set up the timer on the boot CPU (late init function) */ > +int __init init_xen_time(void) > +{ > /* Check that this CPU supports the Generic Timer interface */ > if ( !cpu_has_gentimer ) > panic("CPU does not support the Generic Timer v1 interface"); > -- > 2.0.4 > >