>-----Original Message----- >From: ext Kevin Hilman [mailto:khilman@xxxxxxxxxxxxxxxxxxx] >Sent: 17 November, 2009 20:34 >To: Kristo Tero (Nokia-D/Tampere) >Cc: linux-omap@xxxxxxxxxxxxxxx >Subject: Re: [PATCH] OMAP3: PM: Force write last pad config >register into save area > >Tero Kristo <tero.kristo@xxxxxxxxx> writes: > >> From: Tero Kristo <tero.kristo@xxxxxxxxx> >> >> Due to OMAP3 errata XYZ, the save of the last pad register >(ETK_D14 and >> ETK_D15) can fail sometimes when there is simultaneous OCP >access to the >> SCM register area. Fixed by writing the last register to the >save area. >> >> Also, optimized the delay loop for the HW save to include an >udelay(1), >> which limits the number of unnecessary HW accesses to SCM >register area >> during the save. >> >> Signed-off-by: Tero Kristo <tero.kristo@xxxxxxxxx> > >I certainly like this fix much better than the original proposal: > > http://marc.info/?l=linux-omap&m=125474186609661&w=2 > >Pulling into PM branch after s/XYZ/1.157/ I will resend the patch when TI has confirmed the errata number. This version of the patch was also missing an "#include <linux/delay.h>" for the udelay, I missed this in the hurry, so I will add this one also. -Tero > >> --- >> arch/arm/mach-omap2/pm34xx.c | 10 +++++++++- >> 1 files changed, 9 insertions(+), 1 deletions(-) >> >> diff --git a/arch/arm/mach-omap2/pm34xx.c >b/arch/arm/mach-omap2/pm34xx.c >> index 4b01303..4ead40e 100644 >> --- a/arch/arm/mach-omap2/pm34xx.c >> +++ b/arch/arm/mach-omap2/pm34xx.c >> @@ -155,7 +155,15 @@ static void omap3_core_save_context(void) >> /* wait for the save to complete */ >> while >(!(omap_ctrl_readl(OMAP343X_CONTROL_GENERAL_PURPOSE_STATUS) >> & PADCONF_SAVE_DONE)) >> - ; >> + udelay(1); >> + >> + /* >> + * Force write last pad into memory, as this can fail in some >> + * cases according to errata XYZ >> + */ >> + omap_ctrl_writel(omap_ctrl_readl(OMAP343X_PADCONF_ETK_D14), >> + OMAP343X_CONTROL_MEM_WKUP + 0x2a0); >> + >> /* Save the Interrupt controller context */ >> omap_intc_save_context(); >> /* Save the GPMC context */ >> -- >> 1.5.4.3 >> >> -- >> To unsubscribe from this list: send the line "unsubscribe >linux-omap" in >> the body of a message to majordomo@xxxxxxxxxxxxxxx >> More majordomo info at http://vger.kernel.org/majordomo-info.html >-- To unsubscribe from this list: send the line "unsubscribe linux-omap" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
