From: linux@arm.linux.org.uk (Russell King - ARM Linux)
To: linux-arm-kernel@lists.infradead.org
Subject: [PATCH] ARM: Fix SMP_ON_UP for non ARM ltd. implementations
Date: Sun, 30 Jan 2011 12:20:27 +0000 [thread overview]
Message-ID: <20110130122027.GA22677@n2100.arm.linux.org.uk> (raw)
In-Reply-To: <1296083052-20034-1-git-send-email-sboyd@codeaurora.org>
On Wed, Jan 26, 2011 at 03:04:12PM -0800, Stephen Boyd wrote:
> @@ -393,20 +393,25 @@ ENDPROC(__turn_mmu_on)
> #ifdef CONFIG_SMP_ON_UP
> __fixup_smp:
> mov r4, #0x00070000
> - orr r3, r4, #0xff000000 @ mask 0xff070000
> - orr r4, r4, #0x41000000 @ val 0x41070000
> - and r0, r9, r3
> - teq r0, r4 @ ARM CPU and ARMv6/v7?
> + and r0, r9, r4
> + teq r0, r4 @ ARMv6/v7?
> bne __fixup_smp_on_up @ no, assume UP
>
> + orr r3, r4, #0xff000000 @ mask 0xff070000
> orr r3, r3, #0x0000ff00
> orr r3, r3, #0x000000f0 @ mask 0xff07fff0
> + orr r4, r4, #0x41000000 @ val 0x41070000
> orr r4, r4, #0x0000b000
> orr r4, r4, #0x00000020 @ val 0x4107b020
> and r0, r9, r3
> teq r0, r4 @ ARM 11MPCore?
> moveq pc, lr @ yes, assume SMP
>
> + mov r4, #0x00070000
> + and r0, r9, #0x000f0000
> + teq r0, r4 @ ARMv6?
> + beq __fixup_smp_on_up @ yes, assume UP
> +
Wouldn't it be better to check for CPUID presence first, then ARM11MPcore,
and lastly preserve of MPIDR-flagged extensions?
Will - can you check whether the below is correct?
arch/arm/kernel/head.S | 17 +++++++----------
1 files changed, 7 insertions(+), 10 deletions(-)
diff --git a/arch/arm/kernel/head.S b/arch/arm/kernel/head.S
index 17a97b5..f6b31c4 100644
--- a/arch/arm/kernel/head.S
+++ b/arch/arm/kernel/head.S
@@ -390,19 +390,16 @@ ENDPROC(__turn_mmu_on)
#ifdef CONFIG_SMP_ON_UP
__fixup_smp:
- mov r4, #0x00070000
- orr r3, r4, #0xff000000 @ mask 0xff070000
- orr r4, r4, #0x41000000 @ val 0x41070000
- and r0, r9, r3
- teq r0, r4 @ ARM CPU and ARMv6/v7?
+ and r3, r9, #0x000f0000 @ architecture version
+ teq r3, #0x000f00000 @ CPU ID supported?
bne __fixup_smp_on_up @ no, assume UP
- orr r3, r3, #0x0000ff00
- orr r3, r3, #0x000000f0 @ mask 0xff07fff0
+ bic r3, r9, #0x00ff0000
+ bic r3, r3, #0x0000000f @ mask 0xff00fff0
+ mov r4, #0x41000000
orr r4, r4, #0x0000b000
- orr r4, r4, #0x00000020 @ val 0x4107b020
- and r0, r9, r3
- teq r0, r4 @ ARM 11MPCore?
+ orr r4, r4, #0x00000020 @ val 0x4100b020
+ teq r3, r4 @ ARM 11MPCore?
moveq pc, lr @ yes, assume SMP
mrc p15, 0, r0, c0, c0, 5 @ read MPIDR
next prev parent reply other threads:[~2011-01-30 12:20 UTC|newest]
Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top
2011-01-26 23:04 [PATCH] ARM: Fix SMP_ON_UP for non ARM ltd. implementations Stephen Boyd
2011-01-30 12:20 ` Russell King - ARM Linux [this message]
2011-01-30 16:27 ` Will Deacon
2011-01-30 16:40 ` Russell King - ARM Linux
2011-01-31 10:32 ` Will Deacon
2011-01-31 21:33 ` Stephen Boyd
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20110130122027.GA22677@n2100.arm.linux.org.uk \
--to=linux@arm.linux.org.uk \
--cc=linux-arm-kernel@lists.infradead.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).