From: Christophe Leroy <christophe.leroy@c-s.fr>
To: Benjamin Herrenschmidt <benh@kernel.crashing.org>,
Paul Mackerras <paulus@samba.org>,
scottwood@freescale.com
Cc: linuxppc-dev@lists.ozlabs.org, linux-kernel@vger.kernel.org
Subject: [PATCH v3] powerpc 8xx: Fixing issue with CONFIG_PIN_TLB
Date: Tue, 17 Sep 2013 19:09:27 +0200 [thread overview]
Message-ID: <201309171709.r8HH9Rxo018278@localhost.localdomain> (raw)
Activating CONFIG_PIN_TLB is supposed to pin the IMMR and the first three
8Mbytes pages. But the setting of the MD_CTR was missing so as the index is
decremented every DTLB update, the pinning of the third 8Mbytes page was
overwriting the DTLB entry for IMMR. At the same time, the last entry written
being entry 31, next entries would possibly get overwritten after.
We are now starting from entry 31 and decrementing.
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
diff -ur linux-3.11.org/arch/powerpc/kernel/head_8xx.S linux-3.11/arch/powerpc/kernel/head_8xx.S
--- linux-3.11.org/arch/powerpc/kernel/head_8xx.S 2013-09-02 22:46:10.000000000 +0200
+++ linux-3.11/arch/powerpc/kernel/head_8xx.S 2013-09-09 11:28:54.000000000 +0200
@@ -796,8 +796,7 @@
#ifdef CONFIG_PIN_TLB
lis r10, (MD_RSV4I | MD_RESETVAL)@h
- ori r10, r10, 0x1c00
- mr r8, r10
+ ori r10, r10, 0x1f00
#else
lis r10, MD_RESETVAL@h
#endif
@@ -829,7 +828,7 @@
* internal registers (among other things).
*/
#ifdef CONFIG_PIN_TLB
- addi r10, r10, 0x0100
+ addi r10, r10, -0x0100
mtspr SPRN_MD_CTR, r10
#endif
mfspr r9, 638 /* Get current IMMR */
@@ -848,7 +847,7 @@
#ifdef CONFIG_PIN_TLB
/* Map two more 8M kernel data pages.
*/
- addi r10, r10, 0x0100
+ addi r10, r10, -0x0100
mtspr SPRN_MD_CTR, r10
lis r8, KERNELBASE@h /* Create vaddr for TLB */
@@ -862,6 +861,9 @@
addis r11, r11, 0x0080 /* Add 8M */
mtspr SPRN_MD_RPN, r11
+ addi r10, r10, -0x0100
+ mtspr SPRN_MD_CTR, r10
+
addis r8, r8, 0x0080 /* Add 8M */
mtspr SPRN_MD_EPN, r8
mtspr SPRN_MD_TWC, r9
reply other threads:[~2013-09-17 17:09 UTC|newest]
Thread overview: [no followups] expand[flat|nested] mbox.gz Atom feed
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=201309171709.r8HH9Rxo018278@localhost.localdomain \
--to=christophe.leroy@c-s.fr \
--cc=benh@kernel.crashing.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linuxppc-dev@lists.ozlabs.org \
--cc=paulus@samba.org \
--cc=scottwood@freescale.com \
/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