[PATCHv2 18/19] ARM: OMAP4460: wakeupgen: set GIC_CPU0 backup status flag always

Tero Kristo t-kristo at ti.com
Mon May 21 05:12:34 EDT 2012


On Wed, 2012-05-16 at 17:33 -0700, Kevin Hilman wrote:
> Tero Kristo <t-kristo at ti.com> writes:
> 
> > Without this, CPU0 will crash in the ROM code during wakeup from
> > device off. This patch also clears the GIC save area, to prevent
> > ROM code from writing garbage to the GIC registers during wakeup.
> > The actual GIC restore is done by kernel.
> >
> > This bug fix applies only to OMAP4460, it is fixed on OMAP4470.
> >
> > Signed-off-by: Tero Kristo <t-kristo at ti.com>
> 
> Please create/use PM_ERRATUM flag.

Okay.

-Tero

> 
> Kevin
> 
> > ---
> >  arch/arm/mach-omap2/omap-wakeupgen.c   |   14 ++++++++++++++
> >  arch/arm/mach-omap2/omap4-sar-layout.h |    1 +
> >  2 files changed, 15 insertions(+), 0 deletions(-)
> >
> > diff --git a/arch/arm/mach-omap2/omap-wakeupgen.c b/arch/arm/mach-omap2/omap-wakeupgen.c
> > index c7c4db4..30da299 100644
> > --- a/arch/arm/mach-omap2/omap-wakeupgen.c
> > +++ b/arch/arm/mach-omap2/omap-wakeupgen.c
> > @@ -447,10 +447,24 @@ int __init omap_wakeupgen_init(void)
> >  
> >  	if (omap_type() == OMAP2_DEVICE_TYPE_GP) {
> >  		sar_base = ioremap(OMAP44XX_SAR_RAM_BASE, SZ_16K);
> > +		/* Clean GIC SAR area */
> > +		for (i = SAR_BACKUP_STATUS_OFFSET; i < WAKEUPGENENB_OFFSET_CPU0;
> > +			i += 4)
> > +			sar_writel(0, i, 0);
> > +
> >  		sar_writel(GIC_ISR_NON_SECURE, ICDISR_CPU0_OFFSET, 0);
> >  		sar_writel(GIC_ISR_NON_SECURE, ICDISR_CPU1_OFFSET, 0);
> >  		for (i = 0; i < max_spi_reg; i++)
> >  			sar_writel(GIC_ISR_NON_SECURE, ICDISR_SPI_OFFSET, i);
> > +
> > +		/*
> > +		 * Set CPU0 GIC backup flag permanently for omap4460,
> > +		 * this is needed because of the ROM code bug that breaks
> > +		 * GIC during wakeup from device off
> > +		 */
> > +		if (cpu_is_omap446x())
> > +			__raw_writel(SAR_BACKUP_STATUS_GIC_CPU0,
> > +				     sar_base + SAR_BACKUP_STATUS_OFFSET);
> >  		iounmap(sar_base);
> >  		sar_base = NULL;
> >  	} else {
> > diff --git a/arch/arm/mach-omap2/omap4-sar-layout.h b/arch/arm/mach-omap2/omap4-sar-layout.h
> > index 0056667..e621c51 100644
> > --- a/arch/arm/mach-omap2/omap4-sar-layout.h
> > +++ b/arch/arm/mach-omap2/omap4-sar-layout.h
> > @@ -88,6 +88,7 @@
> >  #define ICDISR_CPU0_OFFSET			(SAR_BANK3_OFFSET + 0x50c)
> >  #define ICDISR_CPU1_OFFSET			(SAR_BANK3_OFFSET + 0x510)
> >  #define ICDISR_SPI_OFFSET			(SAR_BANK3_OFFSET + 0x514)
> > +#define SAR_BACKUP_STATUS_GIC_CPU0		0x1
> >  
> >  /* WakeUpGen save restore offset from OMAP44XX_SAR_RAM_BASE */
> >  #define WAKEUPGENENB_OFFSET_CPU0		(SAR_BANK3_OFFSET + 0x684)





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