Commit 2189e928 authored by Geert Uytterhoeven's avatar Geert Uytterhoeven
Browse files

m68k: Fix invalid RMW_INSNS on CPUs that lack CAS 



When enabling CONFIG_RMW_INSNS in e.g. a Coldfire build:

    {standard input}:3068: Error: invalid instruction for this architecture; needs 68020 or higher (68020 [68k, 68ec020], 68030 [68ec030], 68040 [68ec040], 68060 [68ec060]) -- statement `casl %d4,%d0,(%a6)' ignored

Fix this by (a) adding a new config symbol to track if support for any
CPU that lacks the CAS instruction is enabled, and (b) making
CONFIG_RMW_INSNS depend on the new symbol not being set.

Fixes: 0e152d80 ("m68k: reorganize Kconfig options to improve mmu/non-mmu selections")
Reported-by: default avatarkernel test robot <lkp@intel.com>
Reported-by: default avatarArnd Bergmann <arnd@arndb.de>
Signed-off-by: default avatarGeert Uytterhoeven <geert@linux-m68k.org>
Acked-by: default avatarArnd Bergmann <arnd@arndb.de>
Link: https://lore.kernel.org/r/20210725104413.318932-1-geert@linux-m68k.org
parent 07aa6c73

arch/m68k/Kconfig.cpu

+7 −1
Original line number Diff line number Diff line
@@ -26,6 +26,7 @@ config COLDFIRE 
	bool "Coldfire CPU family support"

	select ARCH_HAVE_CUSTOM_GPIO_H

	select CPU_HAS_NO_BITFIELDS

	select CPU_HAS_NO_CAS

	select CPU_HAS_NO_MULDIV64

	select GENERIC_CSUM

	select GPIOLIB
@@ -39,6 +40,7 @@ config M68000 
	bool

	depends on !MMU

	select CPU_HAS_NO_BITFIELDS

	select CPU_HAS_NO_CAS

	select CPU_HAS_NO_MULDIV64

	select CPU_HAS_NO_UNALIGNED

	select GENERIC_CSUM
@@ -54,6 +56,7 @@ config M68000 
config MCPU32

	bool

	select CPU_HAS_NO_BITFIELDS

	select CPU_HAS_NO_CAS

	select CPU_HAS_NO_UNALIGNED

	select CPU_NO_EFFICIENT_FFS

	help
@@ -383,7 +386,7 @@ config ADVANCED 


config RMW_INSNS

	bool "Use read-modify-write instructions"

	depends on ADVANCED

	depends on ADVANCED && !CPU_HAS_NO_CAS

	help

	  This allows to use certain instructions that work with indivisible

	  read-modify-write bus cycles. While this is faster than the
@@ -450,6 +453,9 @@ config M68K_L2_CACHE 
config CPU_HAS_NO_BITFIELDS

	bool



config CPU_HAS_NO_CAS

	bool



config CPU_HAS_NO_MULDIV64

	bool