From: Albert ARIBAUD <albert.u.boot@aribaud.net>
To: u-boot@lists.denx.de
Subject: [U-Boot] [PATCH 3/9] arm: Move CP15 init out of cpu_init_crit()
Date: Fri, 21 Oct 2011 22:58:44 +0200 [thread overview]
Message-ID: <4EA1DD04.3010808@aribaud.net> (raw)
In-Reply-To: <1318539963-3329-4-git-send-email-sjg@chromium.org>
Le 13/10/2011 23:05, Simon Glass a ?crit :
> Some SOCs have do not start up with their 'main' CPU. The first U-Boot
> code may then be executed with a CPU which does not have a CP15, or not a
> useful one.
>
> Here we split the initialization of CP15 into a separate call, which can
> be performed later if required.
>
> Once the main CPU is running, you should call cpu_init_cp15() to perform
> this init as early as possible.
>
> Existing ARMv7 boards which define CONFIG_SKIP_LOWLEVEL_INIT should not
> need to change, this CP15 init is still skipped in that case. The only
> impact for these boards is that the cpu_init_cp15() will be available
> even if it is never used on these boards.
I'm not too sure I understand how this is working: if you are moving
cp15 init to later, it will still be done by the same core that would
have done it earlier, won't it?
IOW, I would like to better understand how this boot core/main core
business works. How does the main core start execution? At which
address? Does it go through its reset vector? Do the cores share the
same location for reset vectors? Etc.
Amicalement,
--
Albert.
next prev parent reply other threads:[~2011-10-21 20:58 UTC|newest]
Thread overview: 46+ messages / expand[flat|nested] mbox.gz Atom feed top
2011-10-13 21:05 [U-Boot] [PATCH 0/9] tegra2: Tidy up boot path Simon Glass
2011-10-13 21:05 ` [U-Boot] [PATCH 1/9] tegra2: Add arch_cpu_init() to fire up Cortex-A9 Simon Glass
2011-10-13 22:52 ` Mike Frysinger
2011-10-13 23:18 ` Simon Glass
2011-10-13 23:34 ` Mike Frysinger
2011-10-14 0:47 ` Simon Glass
2011-10-13 21:05 ` [U-Boot] [PATCH 2/9] tegra2: Simplify tegra_start() boot path Simon Glass
2011-10-13 21:05 ` [U-Boot] [PATCH 3/9] arm: Move CP15 init out of cpu_init_crit() Simon Glass
2011-10-21 20:58 ` Albert ARIBAUD [this message]
2011-10-21 21:18 ` Simon Glass
2011-10-21 21:43 ` Albert ARIBAUD
2011-10-21 21:54 ` Simon Glass
2011-10-21 22:24 ` Albert ARIBAUD
2011-10-22 5:05 ` Simon Glass
2011-10-22 7:56 ` Albert ARIBAUD
2011-10-22 16:13 ` Simon Glass
2011-10-24 19:34 ` Simon Glass
2011-10-24 20:04 ` Albert ARIBAUD
2011-10-24 20:14 ` Simon Glass
2011-10-24 21:21 ` Albert ARIBAUD
2011-10-25 5:02 ` Simon Glass
2011-10-25 6:41 ` Albert ARIBAUD
2011-10-25 13:44 ` Simon Glass
2011-10-25 21:16 ` Simon Glass
2011-10-27 20:05 ` Albert ARIBAUD
2011-10-27 20:17 ` Simon Glass
2011-10-27 22:39 ` Albert ARIBAUD
2011-10-27 22:46 ` Simon Glass
2011-10-28 1:43 ` Simon Glass
2011-10-28 5:09 ` Albert ARIBAUD
2011-10-29 0:36 ` Simon Glass
2011-10-30 10:16 ` Albert ARIBAUD
2011-10-31 21:44 ` Simon Glass
2011-10-31 22:54 ` Tom Warren
2011-11-05 5:17 ` Simon Glass
2011-11-05 8:09 ` Albert ARIBAUD
2011-11-05 13:36 ` Simon Glass
2011-10-28 5:07 ` Albert ARIBAUD
2011-11-05 8:17 ` Albert ARIBAUD
2011-11-05 14:00 ` Simon Glass
2011-10-13 21:05 ` [U-Boot] [PATCH 4/9] tegra2: Enable instruction cache Simon Glass
2011-10-13 21:05 ` [U-Boot] [PATCH 5/9] tegra2: Remove unneeded boot code Simon Glass
2011-10-13 21:06 ` [U-Boot] [PATCH 6/9] tegra2: Remove unneeded config option Simon Glass
2011-10-13 21:06 ` [U-Boot] [PATCH 7/9] tegra2: Remove unused low-level Tegra2 UART code Simon Glass
2011-10-13 21:06 ` [U-Boot] [PATCH 8/9] tegra2: Remove unneeded 'dynamic ram size' message Simon Glass
2011-10-13 21:06 ` [U-Boot] [PATCH 9/9] tegra2: Don't use board pointer before it is set up Simon Glass
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