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From: Christophe Leroy <christophe.leroy@csgroup.eu>
To: Benjamin Herrenschmidt <benh@kernel.crashing.org>,
	Paul Mackerras <paulus@samba.org>,
	Michael Ellerman <mpe@ellerman.id.au>
Cc: linuxppc-dev@lists.ozlabs.org, linux-kernel@vger.kernel.org
Subject: [PATCH v3 2/8] powerpc: Remove CONFIG_PPC601_SYNC_FIX
Date: Tue, 29 Sep 2020 06:48:33 +0000 (UTC)
Message-ID: <55b46bff16705b1ae7bf0a60ccd522b1010ebf75.1601362098.git.christophe.leroy@csgroup.eu> (raw)
In-Reply-To: <27951fa6c9a8f80724d1bc81a6117ac32343a55d.1601362098.git.christophe.leroy@csgroup.eu>

This config option isn't in any defconfig.

The very first versions of Powerpc 601 have a bug which
requires additional sync before and/or after some instructions.

This was more than 25 years ago and time has come to retire
those buggy versions of the 601 from the kernel.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
---
 arch/powerpc/include/asm/ppc_asm.h |  6 ------
 arch/powerpc/platforms/Kconfig     | 15 ---------------
 2 files changed, 21 deletions(-)

diff --git a/arch/powerpc/include/asm/ppc_asm.h b/arch/powerpc/include/asm/ppc_asm.h
index b4cc6608131c..0b9dc814b81c 100644
--- a/arch/powerpc/include/asm/ppc_asm.h
+++ b/arch/powerpc/include/asm/ppc_asm.h
@@ -382,15 +382,9 @@ GLUE(.,name):
 #endif
 
 /* various errata or part fixups */
-#ifdef CONFIG_PPC601_SYNC_FIX
-#define SYNC		sync; isync
-#define SYNC_601	sync
-#define ISYNC_601	isync
-#else
 #define	SYNC
 #define SYNC_601
 #define ISYNC_601
-#endif
 
 #if defined(CONFIG_PPC_CELL) || defined(CONFIG_PPC_FSL_BOOK3E)
 #define MFTB(dest)			\
diff --git a/arch/powerpc/platforms/Kconfig b/arch/powerpc/platforms/Kconfig
index b439b027a42f..7a5e8f4541e3 100644
--- a/arch/powerpc/platforms/Kconfig
+++ b/arch/powerpc/platforms/Kconfig
@@ -199,21 +199,6 @@ source "drivers/cpuidle/Kconfig"
 
 endmenu
 
-config PPC601_SYNC_FIX
-	bool "Workarounds for PPC601 bugs"
-	depends on PPC_BOOK3S_601 && PPC_PMAC
-	default y
-	help
-	  Some versions of the PPC601 (the first PowerPC chip) have bugs which
-	  mean that extra synchronization instructions are required near
-	  certain instructions, typically those that make major changes to the
-	  CPU state.  These extra instructions reduce performance slightly.
-	  If you say N here, these extra instructions will not be included,
-	  resulting in a kernel which will run faster but may not run at all
-	  on some systems with the PPC601 chip.
-
-	  If in doubt, say Y here.
-
 config TAU
 	bool "On-chip CPU temperature sensor support"
 	depends on PPC_BOOK3S_32
-- 
2.25.0


  reply index

Thread overview: 9+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-09-29  6:48 [PATCH v3 1/8] powerpc: Remove SYNC on non 6xx Christophe Leroy
2020-09-29  6:48 ` Christophe Leroy [this message]
2020-09-29  6:48 ` [PATCH v3 3/8] powerpc: Drop SYNC_601() ISYNC_601() and SYNC() Christophe Leroy
2020-09-29  6:48 ` [PATCH v3 4/8] powerpc: Remove PowerPC 601 Christophe Leroy
2020-09-29  6:48 ` [PATCH v3 5/8] powerpc: Remove support for " Christophe Leroy
2020-09-29  6:48 ` [PATCH v3 6/8] powerpc: Tidy up a bit after removal of " Christophe Leroy
2020-09-29  6:48 ` [PATCH v3 7/8] powerpc: Remove __USE_RTC() Christophe Leroy
2020-09-29  6:48 ` [PATCH v3 8/8] powerpc: Remove get_tb_or_rtc() Christophe Leroy
2020-10-09  6:04 ` [PATCH v3 1/8] powerpc: Remove SYNC on non 6xx Michael Ellerman

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