From: santosh.shilimkar@ti•com (Santosh Shilimkar)
To: linux-arm-kernel@lists•infradead.org
Subject: [PATCH 06/16] ARM: b.L: generic SMP secondary bringup and hotplug support
Date: Tue, 15 Jan 2013 12:02:39 +0530 [thread overview]
Message-ID: <50F4F807.3010806@ti.com> (raw)
In-Reply-To: <CAMpgmWCxQMoncnMqy_bzB+mBU7eGO_L4fR+Q5uMaxdFn4mL5PA@mail.gmail.com>
On Monday 14 January 2013 11:35 PM, Achin Gupta wrote:
> Hi Santosh,
>
> On Fri, Jan 11, 2013 at 6:02 PM, Santosh Shilimkar
> <santosh.shilimkar@ti•com> wrote:
>> On Thursday 10 January 2013 05:50 AM, Nicolas Pitre wrote:
>>>
>>> Now that the b.L power API is in place, we can use it for SMP secondary
>>> bringup and CPU hotplug in a generic fashion.
>>>
>>> Signed-off-by: Nicolas Pitre <nico@linaro•org>
>>> ---
>>> arch/arm/common/Makefile | 2 +-
>>> arch/arm/common/bL_platsmp.c | 79
>>> ++++++++++++++++++++++++++++++++++++++++++++
>>> 2 files changed, 80 insertions(+), 1 deletion(-)
>>> create mode 100644 arch/arm/common/bL_platsmp.c
>>>
>>> diff --git a/arch/arm/common/Makefile b/arch/arm/common/Makefile
>>> index 894c2ddf9b..59b36db7cc 100644
>>> --- a/arch/arm/common/Makefile
>>> +++ b/arch/arm/common/Makefile
>>> @@ -15,4 +15,4 @@ obj-$(CONFIG_PCI_HOST_ITE8152) += it8152.o
>>> obj-$(CONFIG_ARM_TIMER_SP804) += timer-sp.o
>>> obj-$(CONFIG_FIQ_GLUE) += fiq_glue.o fiq_glue_setup.o
>>> obj-$(CONFIG_FIQ_DEBUGGER) += fiq_debugger.o
>>> -obj-$(CONFIG_BIG_LITTLE) += bL_head.o bL_entry.o vlock.o
>>> +obj-$(CONFIG_BIG_LITTLE) += bL_head.o bL_entry.o bL_platsmp.o
>>> vlock.o
>>> diff --git a/arch/arm/common/bL_platsmp.c b/arch/arm/common/bL_platsmp.c
>>> new file mode 100644
>>> index 0000000000..0acb9f4685
>>> --- /dev/null
>>> +++ b/arch/arm/common/bL_platsmp.c
>>> @@ -0,0 +1,79 @@
>>> +/*
>>> + * linux/arch/arm/mach-vexpress/bL_platsmp.c
>>> + *
>>> + * Created by: Nicolas Pitre, November 2012
>>> + * Copyright: (C) 2012 Linaro Limited
>>> + *
>>> + * This program is free software; you can redistribute it and/or modify
>>> + * it under the terms of the GNU General Public License version 2 as
>>> + * published by the Free Software Foundation.
>>> + *
>>> + * Code to handle secondary CPU bringup and hotplug for the bL power API.
>>> + */
>>> +
>>> +#include <linux/init.h>
>>> +#include <linux/smp.h>
>>> +
>>> +#include <asm/bL_entry.h>
>>> +#include <asm/smp_plat.h>
>>> +#include <asm/hardware/gic.h>
>>> +
>>> +static void __init simple_smp_init_cpus(void)
>>> +{
>>> + set_smp_cross_call(gic_raise_softirq);
>>> +}
>>> +
>>> +static int __cpuinit bL_boot_secondary(unsigned int cpu, struct
>>> task_struct *idle)
>>> +{
>>> + unsigned int pcpu, pcluster, ret;
>>> + extern void secondary_startup(void);
>>> +
>>> + pcpu = cpu_logical_map(cpu) & 0xff;
>>> + pcluster = (cpu_logical_map(cpu) >> 8) & 0xff;
>>> + pr_debug("%s: logical CPU %d is physical CPU %d cluster %d\n",
>>> + __func__, cpu, pcpu, pcluster);
>>> +
>>> + bL_set_entry_vector(pcpu, pcluster, NULL);
>>> + ret = bL_cpu_power_up(pcpu, pcluster);
>>> + if (ret)
>>> + return ret;
>>> + bL_set_entry_vector(pcpu, pcluster, secondary_startup);
>>> + gic_raise_softirq(cpumask_of(cpu), 0);
>>> + sev();
>>
>> softirq() should be enough to break a CPU if it is in standby with
>> wfe state. Is that additional sev() needed here ?
>
> Not if the target cpu has its I & F bits disabled and that would be the
> case with a secondary waiting to be woken up
>
This is interesting since CPU is actually in standby state and this
was not my understanding so far. Your statement at least contradicts
the ARM ARM (B1.8.12 Wait For Interrupt)
-----------------------
The processor can remain in the WFI low-power state until it is reset,
or it detects one of the following WFI wake-up
events:
? a physical IRQ interrupt, regardless of the value of the CPSR.I bit
? a physical FIQ interrupt, regardless of the value of the CPSR.F bit
----------------------------------
Are you referring to some new behavior on latest ARMv7 CPUs ?
Regards,
Santosh
next prev parent reply other threads:[~2013-01-15 6:32 UTC|newest]
Thread overview: 132+ messages / expand[flat|nested] mbox.gz Atom feed top
2013-01-10 0:20 [PATCH 00/16] big.LITTLE low-level CPU and cluster power management Nicolas Pitre
2013-01-10 0:20 ` [PATCH 01/16] ARM: b.L: secondary kernel entry code Nicolas Pitre
2013-01-10 7:12 ` Stephen Boyd
2013-01-10 15:30 ` Nicolas Pitre
2013-01-10 15:34 ` Catalin Marinas
2013-01-10 16:47 ` Nicolas Pitre
2013-01-11 11:45 ` Catalin Marinas
2013-01-11 12:05 ` Lorenzo Pieralisi
2013-01-11 12:19 ` Dave Martin
2013-01-10 23:05 ` Will Deacon
2013-01-11 1:26 ` Nicolas Pitre
2013-01-11 10:55 ` Will Deacon
2013-01-11 11:35 ` Dave Martin
2013-01-11 17:16 ` Santosh Shilimkar
2013-01-11 18:10 ` Nicolas Pitre
2013-01-11 18:30 ` Santosh Shilimkar
2013-03-07 7:37 ` Pavel Machek
2013-03-07 8:57 ` Nicolas Pitre
2013-01-10 0:20 ` [PATCH 02/16] ARM: b.L: introduce the CPU/cluster power API Nicolas Pitre
2013-01-10 23:08 ` Will Deacon
2013-01-11 2:30 ` Nicolas Pitre
2013-01-11 10:58 ` Will Deacon
2013-01-11 11:29 ` Dave Martin
2013-01-11 17:26 ` Santosh Shilimkar
2013-01-11 18:33 ` Nicolas Pitre
2013-01-11 18:41 ` Santosh Shilimkar
2013-01-11 19:54 ` Nicolas Pitre
2013-01-10 0:20 ` [PATCH 03/16] ARM: b.L: introduce helpers for platform coherency exit/setup Nicolas Pitre
2013-01-10 12:01 ` Dave Martin
2013-01-10 19:04 ` Nicolas Pitre
2013-01-11 11:30 ` Dave Martin
2013-01-10 16:53 ` Catalin Marinas
2013-01-10 17:59 ` Nicolas Pitre
2013-01-10 21:50 ` Catalin Marinas
2013-01-10 22:31 ` Nicolas Pitre
2013-01-11 10:36 ` Dave Martin
2013-01-10 22:32 ` Nicolas Pitre
2013-01-10 23:13 ` Will Deacon
2013-01-11 1:50 ` Nicolas Pitre
2013-01-11 11:09 ` Dave Martin
2013-01-11 17:46 ` Santosh Shilimkar
2013-01-11 18:07 ` Dave Martin
2013-01-11 18:34 ` Santosh Shilimkar
2013-01-14 17:08 ` Dave Martin
2013-01-14 17:15 ` Catalin Marinas
2013-01-14 18:10 ` Dave Martin
2013-01-14 21:34 ` Catalin Marinas
2013-01-10 0:20 ` [PATCH 04/16] ARM: b.L: Add baremetal voting mutexes Nicolas Pitre
2013-01-10 23:18 ` Will Deacon
2013-01-11 3:15 ` Nicolas Pitre
2013-01-11 11:03 ` Will Deacon
2013-01-11 16:57 ` Dave Martin
2013-01-10 0:20 ` [PATCH 05/16] ARM: bL_head: vlock-based first man election Nicolas Pitre
2013-01-10 0:20 ` [PATCH 06/16] ARM: b.L: generic SMP secondary bringup and hotplug support Nicolas Pitre
2013-01-11 18:02 ` Santosh Shilimkar
2013-01-14 18:05 ` Achin Gupta
2013-01-15 6:32 ` Santosh Shilimkar [this message]
2013-01-15 11:18 ` Achin Gupta
2013-01-15 11:26 ` Santosh Shilimkar
2013-01-15 18:53 ` Dave Martin
2013-01-14 16:35 ` Will Deacon
2013-01-14 16:51 ` Nicolas Pitre
2013-01-15 19:09 ` Dave Martin
2013-01-10 0:20 ` [PATCH 07/16] ARM: bL_platsmp.c: close the kernel entry gate before hot-unplugging a CPU Nicolas Pitre
2013-01-14 16:37 ` Will Deacon
2013-01-14 16:53 ` Nicolas Pitre
2013-01-14 17:00 ` Will Deacon
2013-01-14 17:11 ` Catalin Marinas
2013-01-14 17:15 ` Nicolas Pitre
2013-01-14 17:23 ` Will Deacon
2013-01-14 18:26 ` Russell King - ARM Linux
2013-01-14 18:49 ` Nicolas Pitre
2013-01-15 18:40 ` Dave Martin
2013-01-16 16:06 ` Catalin Marinas
2013-01-10 0:20 ` [PATCH 08/16] ARM: bL_platsmp.c: make sure the GIC interface of a dying CPU is disabled Nicolas Pitre
2013-01-11 18:07 ` Santosh Shilimkar
2013-01-11 19:07 ` Nicolas Pitre
2013-01-12 6:50 ` Santosh Shilimkar
2013-01-12 16:47 ` Nicolas Pitre
2013-01-13 4:37 ` Santosh Shilimkar
2013-01-14 17:53 ` Lorenzo Pieralisi
2013-01-14 16:39 ` Will Deacon
2013-01-14 16:54 ` Nicolas Pitre
2013-01-14 17:02 ` Will Deacon
2013-01-14 17:18 ` Nicolas Pitre
2013-01-14 17:24 ` Will Deacon
2013-01-14 17:56 ` Lorenzo Pieralisi
2013-01-10 0:20 ` [PATCH 09/16] ARM: vexpress: Select the correct SMP operations at run-time Nicolas Pitre
2013-01-10 0:20 ` [PATCH 10/16] ARM: vexpress: introduce DCSCB support Nicolas Pitre
2013-01-11 18:12 ` Santosh Shilimkar
2013-01-11 19:13 ` Nicolas Pitre
2013-01-12 6:52 ` Santosh Shilimkar
2013-01-10 0:20 ` [PATCH 11/16] ARM: vexpress/dcscb: add CPU use counts to the power up/down API implementation Nicolas Pitre
2013-01-10 0:20 ` [PATCH 12/16] ARM: vexpress/dcscb: do not hardcode number of CPUs per cluster Nicolas Pitre
2013-01-10 0:20 ` [PATCH 13/16] drivers: misc: add ARM CCI support Nicolas Pitre
2013-01-11 18:20 ` Santosh Shilimkar
2013-01-11 19:22 ` Nicolas Pitre
2013-01-12 6:53 ` Santosh Shilimkar
2013-01-15 18:34 ` Dave Martin
2013-01-10 0:20 ` [PATCH 14/16] ARM: TC2: ensure powerdown-time data is flushed from cache Nicolas Pitre
2013-01-10 18:50 ` Dave Martin
2013-01-10 19:13 ` Nicolas Pitre
2013-01-11 11:38 ` Dave Martin
2013-01-10 0:20 ` [PATCH 15/16] ARM: vexpress/dcscb: handle platform coherency exit/setup and CCI Nicolas Pitre
2013-01-10 12:05 ` Dave Martin
2013-01-11 18:27 ` Santosh Shilimkar
2013-01-11 19:28 ` Nicolas Pitre
2013-01-12 7:21 ` Santosh Shilimkar
2013-01-14 12:25 ` Lorenzo Pieralisi
2013-01-15 6:23 ` Santosh Shilimkar
2013-01-15 18:20 ` Dave Martin
2013-01-16 6:33 ` Santosh Shilimkar
2013-01-16 10:03 ` Lorenzo Pieralisi
2013-01-16 10:12 ` Santosh Shilimkar
2013-01-10 0:20 ` [PATCH 16/16] ARM: vexpress/dcscb: probe via device tree Nicolas Pitre
2013-01-10 0:46 ` [PATCH 00/16] big.LITTLE low-level CPU and cluster power management Rob Herring
2013-01-10 5:04 ` Nicolas Pitre
2013-01-10 23:01 ` Will Deacon
2013-01-14 9:56 ` Joseph Lo
2013-01-14 14:05 ` Nicolas Pitre
2013-01-15 2:44 ` Joseph Lo
2013-01-15 16:44 ` Nicolas Pitre
2013-01-16 16:02 ` Catalin Marinas
2013-01-16 21:18 ` Nicolas Pitre
2013-01-17 17:55 ` Catalin Marinas
2013-01-15 18:31 ` Dave Martin
2013-03-07 8:27 ` Pavel Machek
2013-03-07 9:12 ` Nicolas Pitre
2013-03-07 9:40 ` Pavel Machek
2013-03-07 9:56 ` Nicolas Pitre
2013-03-07 14:51 ` Pavel Machek
2013-03-07 15:42 ` Nicolas Pitre
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