Subject: [PATCHv1] arm:socfpga: Enable SMP for socfpga

From: [email-masked] (Rob Herring)
Date: Wed, 17 Oct 2012 14:07:41 -0500

On 10/17/2012 02:18 PM, dinguyen at altera.com wrote:
> From: Dinh Nguyen <[email-masked]>
> 
> Enable SMP for the SOCFPGA platform.
> 
> Signed-off-by: Pavel Machek <[email-masked]>
> Signed-off-by: Dinh Nguyen <[email-masked]>
> ---
>  arch/arm/boot/dts/socfpga.dtsi            |   10 ++
>  arch/arm/configs/socfpga_defconfig        |    9 +-

Does the multi_v7_defconfig not work for you?

>  arch/arm/mach-socfpga/Kconfig             |    1 +
>  arch/arm/mach-socfpga/Makefile            |    3 +
>  arch/arm/mach-socfpga/headsmp.S           |   64 +++++++++++
>  arch/arm/mach-socfpga/include/mach/core.h |   33 ++++++

Move core.h to mach-socfpga.

>  arch/arm/mach-socfpga/platsmp.c           |  166 +++++++++++++++++++++++++++++
>  arch/arm/mach-socfpga/socfpga.c           |   33 +++++-
>  8 files changed, 315 insertions(+), 4 deletions(-)
>  create mode 100644 arch/arm/mach-socfpga/headsmp.S
>  create mode 100644 arch/arm/mach-socfpga/include/mach/core.h
>  create mode 100644 arch/arm/mach-socfpga/platsmp.c
> 
> diff --git a/arch/arm/boot/dts/socfpga.dtsi b/arch/arm/boot/dts/socfpga.dtsi
> index 0772f57..19aec42 100644
> --- a/arch/arm/boot/dts/socfpga.dtsi
> +++ b/arch/arm/boot/dts/socfpga.dtsi
> @@ -143,5 +143,15 @@
>  			reg-shift = <2>;
>  			reg-io-width = <4>;
>  		};
> +
> +		rstmgr at ffd05000 {
> +				compatible = "altr,rst-mgr";
> +				reg = <0xffd05000 0x1000>;
> +			};
> +
> +		sysmgr at ffd08000 {
> +				compatible = "altr,sys-mgr";
> +				reg = <0xffd08000 0x4000>;
> +			};

Bindings need documentation.

>  	};
>  };
> diff --git a/arch/arm/configs/socfpga_defconfig b/arch/arm/configs/socfpga_defconfig
> index 0ac1293..349ac22 100644
> --- a/arch/arm/configs/socfpga_defconfig
> +++ b/arch/arm/configs/socfpga_defconfig
> @@ -1,5 +1,5 @@
>  CONFIG_EXPERIMENTAL=y
> -CONFIG_SYSVIPC=y
> +CONFIG_NO_HZ=y
>  CONFIG_IKCONFIG=y
>  CONFIG_IKCONFIG_PROC=y
>  CONFIG_LOG_BUF_SHIFT=14
> @@ -16,10 +16,13 @@ CONFIG_MODULE_UNLOAD=y
>  # CONFIG_IOSCHED_DEADLINE is not set
>  # CONFIG_IOSCHED_CFQ is not set
>  CONFIG_ARCH_SOCFPGA=y
> -CONFIG_MACH_SOCFPGA_CYCLONE5=y
> -CONFIG_ARM_THUMBEE=y
> +# CONFIG_ARCH_VEXPRESS_CORTEX_A5_A9_ERRATA is not set
>  # CONFIG_CACHE_L2X0 is not set
>  CONFIG_HIGH_RES_TIMERS=y
> +CONFIG_SMP=y
> +CONFIG_ARM_ARCH_TIMER=y
> +CONFIG_HIGHMEM=y
> +CONFIG_HIGHPTE=y
>  CONFIG_VMSPLIT_2G=y
>  CONFIG_NR_CPUS=2
>  CONFIG_AEABI=y
> diff --git a/arch/arm/mach-socfpga/Kconfig b/arch/arm/mach-socfpga/Kconfig
> index 803a328..566e804 100644
> --- a/arch/arm/mach-socfpga/Kconfig
> +++ b/arch/arm/mach-socfpga/Kconfig
> @@ -12,5 +12,6 @@ config ARCH_SOCFPGA
>  	select GENERIC_CLOCKEVENTS
>  	select GPIO_PL061 if GPIOLIB
>  	select HAVE_ARM_SCU
> +	select HAVE_SMP
>  	select SPARSE_IRQ
>  	select USE_OF
> diff --git a/arch/arm/mach-socfpga/Makefile b/arch/arm/mach-socfpga/Makefile
> index 4fb9324..61b1266 100644
> --- a/arch/arm/mach-socfpga/Makefile
> +++ b/arch/arm/mach-socfpga/Makefile
> @@ -2,4 +2,7 @@
>  # Makefile for the linux kernel.
>  #
>  
> +ccflags-$(CONFIG_ARCH_MULTIPLATFORM) := -I$(srctree)/$(src)/include
> +

This can be removed if core.h is moved.

>  obj-y					:= socfpga.o
> +obj-$(CONFIG_SMP)	+= headsmp.o platsmp.o
> diff --git a/arch/arm/mach-socfpga/headsmp.S b/arch/arm/mach-socfpga/headsmp.S
> new file mode 100644
> index 0000000..b3a24db
> --- /dev/null
> +++ b/arch/arm/mach-socfpga/headsmp.S
> @@ -0,0 +1,64 @@
> +/*
> + *  Copyright (c) 2003 ARM Limited
> + *  Copyright (c) u-boot contributors
> + *  Copyright (c) 2012 Pavel Machek <[email-masked]>
> + *
> + * 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.
> + */
> +#include <linux/linkage.h>
> +#include <linux/init.h>
> +
> +	__INIT
> +
> +#define CPU1_START_ADDR 	        0xffd08010
> +
> +ENTRY(secondary_trampoline)

This appears to be your reset code at phys addr 0. How does core 0 boot
if you are copying this to 0?

> +	/* From u-boot: start.S */
> +	mrs     r0, cpsr
> +	bic     r0, r0, #0x1f
> +	orr     r0, r0, #0xd3
> +	msr     cpsr,r0
> +
> +/*************************************************************************
> + *
> + * cpu_init_cp15
> + **  Copyright (c) u-boot contributors
> + * Setup CP15 registers (cache, MMU, TLBs). The I-cache is turned on unless
> + * CONFIG_SYS_ICACHE_OFF is defined.
> + *
> + *************************************************************************/
> +ENTRY(cpu_init_cp15)
> +	/*
> +	 * Invalidate L1 I/D
> +	 */
> +	mov	r0, #0			@ set up for MCR
> +	mcr	p15, 0, r0, c8, c7, 0	@ invalidate TLBs
> +	mcr	p15, 0, r0, c7, c5, 0	@ invalidate icache
> +	mcr	p15, 0, r0, c7, c5, 6	@ invalidate BP array
> +	mcr   p15, 0, r0, c7, c10, 4	@ DSB
> +	mcr   p15, 0, r0, c7, c5, 4	@ ISB
> +
> +	/*
> +	 * disable MMU stuff and caches
> +	 */
> +	mrc	p15, 0, r0, c1, c0, 0
> +	bic	r0, r0, #0x00002000	@ clear bits 13 (--V-)
> +	bic	r0, r0, #0x00000007	@ clear bits 2:0 (-CAM)
> +	orr	r0, r0, #0x00000002	@ set bit 1 (--A-) Align
> +	orr	r0, r0, #0x00000800	@ set bit 11 (Z---) BTB
> +	orr	r0, r0, #0x00001000	@ set bit 12 (I) I-cache

All this should get done by v7_setup.

> +	mcr	p15, 0, r0, c1, c0, 0
> +
> +	movw	r0, #:lower16:CPU1_START_ADDR
> +	movt  r0, #:upper16:CPU1_START_ADDR
> +
> +	ldr	r1, [r0]
> +	bx	r1
> +
> +ENTRY(secondary_trampoline_end)
> +
> +	.align
> +	.long	pen_release
> +
> diff --git a/arch/arm/mach-socfpga/include/mach/core.h b/arch/arm/mach-socfpga/include/mach/core.h
> new file mode 100644
> index 0000000..74a4949
> --- /dev/null
> +++ b/arch/arm/mach-socfpga/include/mach/core.h
> @@ -0,0 +1,33 @@
> +/*
> + * Copyright 2012 Pavel Machek <[email-masked]>
> + * Copyright (C) 2012 Altera Corporation
> + *
> + * This program is free software; you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License as published by
> + * the Free Software Foundation; either version 2 of the License, or
> + * (at your option) any later version.
> + *
> + * This program is distributed in the hope that it will be useful,
> + * but WITHOUT ANY WARRANTY; without even the implied warranty of
> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
> + * GNU General Public License for more details.
> + *
> + * You should have received a copy of the GNU General Public License
> + * along with this program; if not, write to the Free Software
> + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
> + */
> +
> +#ifndef __MACH_CORE_H
> +#define __MACH_CORE_H
> +
> +extern void secondary_startup(void);
> +extern void __iomem *socfpga_scu_base_addr;
> +
> +extern void socfpga_init_clocks(void);
> +extern void socfpga_sysmgr_init(void);
> +
> +extern struct smp_operations socfpga_smp_ops;
> +
> +#define SOCFPGA_SCU_VIRT_BASE   0xfffec000
> +
> +#endif
> diff --git a/arch/arm/mach-socfpga/platsmp.c b/arch/arm/mach-socfpga/platsmp.c
> new file mode 100644
> index 0000000..59d7069
> --- /dev/null
> +++ b/arch/arm/mach-socfpga/platsmp.c
> @@ -0,0 +1,166 @@
> +/*
> + * Copyright 2010-2011 Calxeda, Inc.
> + * Copyright 2012 Pavel Machek <[email-masked]>
> + * Based on platsmp.c, Copyright (C) 2002 ARM Ltd.
> + * Copyright (C) 2012 Altera Corporation
> + *
> + * This program is free software; you can redistribute it and/or modify it
> + * under the terms and conditions of the GNU General Public License,
> + * version 2, as published by the Free Software Foundation.
> + *
> + * This program is distributed in the hope it will be useful, but WITHOUT
> + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
> + * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
> + * more details.
> + *
> + * You should have received a copy of the GNU General Public License along with
> + * this program.  If not, see <http://www.gnu.org/licenses/>.
> + */
> +#include <linux/delay.h>
> +#include <linux/init.h>
> +#include <linux/smp.h>
> +#include <linux/io.h>
> +#include <linux/of.h>
> +#include <linux/of_address.h>
> +
> +#include <asm/cacheflush.h>
> +#include <asm/hardware/gic.h>
> +#include <asm/smp_scu.h>
> +#include <asm/smp_plat.h>
> +
> +#include <mach/core.h>
> +
> +static void __iomem *sys_manager_base_addr;
> +static void __iomem *rst_manager_base_addr;
> +
> +static DEFINE_SPINLOCK(boot_lock);
> +
> +static void __cpuinit socfpga_secondary_init(unsigned int cpu)
> +{
> +	/*
> +	 * if any interrupts are already enabled for the primary
> +	 * core (e.g. timer irq), then they will not have been enabled
> +	 * for us: do so
> +	 */
> +	gic_secondary_init(0);
> +
> +	/*
> +	 * let the primary processor know we're out of the
> +	 * pen, then head off into the C entry point
> +	 */
> +	pen_release = -1;
> +	smp_wmb();
> +
> +	/*
> +	 * Synchronise with the boot thread.
> +	 */
> +	spin_lock(&boot_lock);
> +	spin_unlock(&boot_lock);
> +}
> +
> +static int __cpuinit socfpga_boot_secondary(unsigned int cpu, struct task_struct *idle)
> +{
> +	unsigned long timeout;
> +	extern char secondary_trampoline, secondary_trampoline_end;
> +
> +	int trampoline_size = &secondary_trampoline_end - &secondary_trampoline;
> +
> +	/*
> +	 * Set synchronisation state between this boot processor
> +	 * and the secondary one
> +	 */
> +	spin_lock(&boot_lock);
> +
> +	memcpy(phys_to_virt(0), &secondary_trampoline, trampoline_size);
> +
> +	__raw_writel(virt_to_phys(secondary_startup), (sys_manager_base_addr+0x10));
> +
> +	pen_release = 0;
> +	flush_cache_all();
> +	smp_wmb();
> +	outer_clean_range(0, trampoline_size);
> +
> +	/* This will release CPU #1 out of reset.*/
> +	__raw_writel(0, rst_manager_base_addr + 0x10);
> +
> +	timeout = jiffies + (1 * HZ);
> +	while (time_before(jiffies, timeout)) {
> +		smp_rmb();
> +		if (pen_release == -1)
> +			break;
> +
> +		udelay(10);
> +	}
> +
> +	/*
> +	 * now the secondary core is starting up let it run its
> +	 * calibrations, then wait for it to finish
> +	 */
> +	spin_unlock(&boot_lock);
> +	return pen_release != -1 ? -ENOSYS : 0;

You don't need any of this if you can reset secondary cores on hotplug.

Rob