Hello li.xi...@freescale.com, On Mon, 17 Nov 2014 02:16:11 +0000, li.xi...@freescale.com <li.xi...@freescale.com> wrote: > Hi Albert, > > > > -----Original Message----- > > From: Albert ARIBAUD [mailto:albert.u.b...@aribaud.net] > > Sent: Friday, November 14, 2014 7:45 PM > > To: Xiubo Li-B47053 > > Cc: Sun York-R58495; Jin Zhengxiong-R64188; u-boot@lists.denx.de > > Subject: Re: [PATCH v3 3/5] ls102xa: HYP/non-sec: support for ls102xa boards > > > > Hello li.xi...@freescale.com, > > > > On Fri, 14 Nov 2014 09:06:13 +0000, li.xi...@freescale.com > > <li.xi...@freescale.com> wrote: > > > Hi Albert, > > > > > > > > +#if defined(CONFIG_ARMV7_NONSEC) || defined(CONFIG_ARMV7_VIRT) > > > > > +/* Setting the address at which secondary cores start from.*/ > > > > > +void smp_set_core_boot_addr(unsigned long addr, int corenr) > > > > > +{ > > > > > + struct ccsr_gur __iomem *gur = (void > > > > > *)(CONFIG_SYS_FSL_GUTS_ADDR); > > > > > + > > > > > + /* > > > > > + * After setting the secondary cores start address, > > > > > + * just release them to boot. > > > > > + */ > > > > > + out_be32(&gur->scratchrw[0], addr); > > > > > + out_be32(&gur->brrl, 0x2); > > > > > +} > > > > > > > > This function does not exactly "[set] the address at which secondary > > > > cores start from"; it sets *a* secondary core's boot address, and then > > > > it *boots* it. > > > > > > > > > > Okay, I will fix it later. > > > > > > > Why does this version of smp_set_core_boot_addr() need to boot the core > > > > in addition to setting the address, whereas the existing ones in > > > > virt_v7, vexpress_common and arndale don't boot the cores? > > > > > > > > > > Yes, they don't doing the release operation. > > > > > > For Low Power Management requirement, maybe only one core will be used, > > > and > > then > > > We also make sure that the secondary core must be in low power and deep > > sleep > > > mode(using wfi). So I just release it here, to make sure that the wfi > > instruction > > > will be executed as early as possible. > > > > Right after smp_set_core_boot_addr() is called, kick_all_cpus() isgoing > > to be called. Wouldn't that boot your CPUs just as well? > > > > Yes, it will. > > But before that we must do the holdoff bit set operation as the SoC's > requirement. > > The BRR contains control bits for enabling boot for each core. On exiting > HRESET or > PORESET, the RCW BOOT_HO field optionally allows for logical core 0 to be > released > for booting or to remain in boot holdoff. All other cores remain in boot > holdoff until their > corresponding bit is set. > > Maybe the comment is not very clear and a bit confusing.
Before I'm lost entirely, do you mean that the comment: > > > > > + /* > > > > > + * After setting the secondary cores start address, > > > > > + * just release them to boot. > > > > > + */ Is actually wrong, and the instructions that follow it do not actually boot the secondary core(s)? > Thanks, > > BRs > Xiubo Amicalement, -- Albert. _______________________________________________ U-Boot mailing list U-Boot@lists.denx.de http://lists.denx.de/mailman/listinfo/u-boot
