Subject: [PATCH v4 5/5] ARM: BCM: Add SMP support for Broadcom 4708

From: [email-masked] (Jon Mason)
Date: Thu, 3 Dec 2015 16:08:36 -0500

On Wed, Dec 02, 2015 at 04:03:03PM +0100, Hauke Mehrtens wrote:
> On 12/01/2015 05:24 PM, Kapil Hali wrote:
> > From: Jon Mason <[email-masked]>
> > 
> > Add SMP support for Broadcom's 4708 SoCs.
> > 
> > Signed-off-by: Jon Mason <[email-masked]>
> > Acked-by: Hauke Mehrtens <[email-masked]>
> > Tested-by: Hauke Mehrtens <[email-masked]>
> > Signed-off-by: Kapil Hali <[email-masked]>
> > ---
> >  arch/arm/boot/dts/bcm4708.dtsi | 2 ++
> >  arch/arm/mach-bcm/Kconfig      | 1 +
> >  arch/arm/mach-bcm/Makefile     | 3 +++
> >  3 files changed, 6 insertions(+)
> > 
> > diff --git a/arch/arm/boot/dts/bcm4708.dtsi b/arch/arm/boot/dts/bcm4708.dtsi
> > index 31141e8..eed4dd1 100644
> > --- a/arch/arm/boot/dts/bcm4708.dtsi
> > +++ b/arch/arm/boot/dts/bcm4708.dtsi
> > @@ -15,6 +15,7 @@
> >  	cpus {
> >  		#address-cells = <1>;
> >  		#size-cells = <0>;
> > +		enable-method = "brcm,bcm-nsp-smp";
> >  
> >  		cpu at 0 {
> >  			device_type = "cpu";
> > @@ -27,6 +28,7 @@
> >  			device_type = "cpu";
> >  			compatible = "arm,cortex-a9";
> >  			next-level-cache = <&L2>;
> > +			secondary-boot-reg = <0xffff0400>;
> >  			reg = <0x1>;
> >  		};
> >  	};
> > diff --git a/arch/arm/mach-bcm/Kconfig b/arch/arm/mach-bcm/Kconfig
> > index 83765a0..e85246f 100644
> > --- a/arch/arm/mach-bcm/Kconfig
> > +++ b/arch/arm/mach-bcm/Kconfig
> > @@ -54,6 +54,7 @@ config ARCH_BCM_NSP
> >  config ARCH_BCM_5301X
> >  	bool "Broadcom BCM470X / BCM5301X ARM SoC" if ARCH_MULTI_V7
> >  	select ARCH_BCM_IPROC
> > +	select HAVE_SMP
> >  	help
> >  	  Support for Broadcom BCM470X and BCM5301X SoCs with ARM CPU cores.
> >  
> 
> When applying this patch please make sure it is correctly applied this
> patch causes some problems here:
> 
> http://www.spinics.net/lists/arm-kernel/msg462137.html
> 
> > diff --git a/arch/arm/mach-bcm/Makefile b/arch/arm/mach-bcm/Makefile
> > index 5193a25..7d66515 100644
> > --- a/arch/arm/mach-bcm/Makefile
> > +++ b/arch/arm/mach-bcm/Makefile
> > @@ -43,6 +43,9 @@ obj-$(CONFIG_ARCH_BCM2835)	+= board_bcm2835.o
> >  
> >  # BCM5301X
> >  obj-$(CONFIG_ARCH_BCM_5301X)	+= bcm_5301x.o
> > +ifeq ($(CONFIG_ARCH_BCM_5301X),y)
> > +obj-$(CONFIG_SMP)		+= platsmp.o
> > +endif
> >  
> >  # BCM63XXx
> >  ifeq ($(CONFIG_ARCH_BCM_63XX),y)
> > 
> 
> I am getting this on a Northstar 1 / BCM4708:
> 
> [ 0.137634] CPU0: thread -1, cpu 0, socket 0, mpidr 80000000
> [ 0.143643] Setting up static identity map for 0x82a0 - 0x82d4
> [ 0.189772] CPU1: thread -1, cpu 1, socket 0, mpidr 80000001
> [ 0.189861] Brought up 2 CPUs
> [ 0.198845] SMP: Total of 2 processors activated (3188.32 BogoMIPS).
> [ 0.205446] CPU: WARNING: CPU(s) started in wrong/inconsistent modes
> (primary CPU mode 0x13)
> [ 0.214167] CPU: This may indicate a broken bootloader or firmware.
> 
> I assume that this is correct and the bootloader is just broken, it uses
> this bootloader: "CFE for Foxconn Router version: v1.0.14", I haven't
> noticed any problems, so it is ok for me.

On my 4708 SVK, I see the same issue

[    0.090877] CPU: Testing write buffer coherency: ok
[    0.091231] CPU0: thread -1, cpu 0, socket 0, mpidr 80000000
[    0.091377] Setting up static identity map for 0x82a0 - 0x82f8
[    0.130146] CPU1: thread -1, cpu 1, socket 0, mpidr 80000001
[    0.130251] Brought up 2 CPUs
[    0.130323] SMP: Total of 2 processors activated (3188.32 BogoMIPS).
[    0.130345] CPU: WARNING: CPU(s) started in wrong/inconsistent modes (primary CPU mode 0x13)
[    0.130374] CPU: This may indicate a broken bootloader or firmware.

I'll investigate it more and see if I can bottom out on the cause.

Thanks,
Jon

> Hauke