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authorGeert Uytterhoeven <geert@linux-m68k.org>2022-05-13 14:50:28 +0200
committerGeert Uytterhoeven <geert@linux-m68k.org>2022-05-16 10:33:39 +0200
commited6bc6bf0a7d75e80eb1df883c09975ebb74e590 (patch)
tree4152ac8a07a354edbae13bfbb6011678f386d64a /arch/m68k/Kconfig.cpu
parent4fbdb1a9e9e5c802080aa86c8d557135922fb859 (diff)
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m68k: math-emu: Fix dependencies of math emulation support
If CONFIG_M54xx=y, CONFIG_MMU=y, and CONFIG_M68KFPU_EMU=y: {standard input}:272: Error: invalid instruction for this architecture; needs 68000 or higher (68000 [68ec000, 68hc000, 68hc001, 68008, 68302, 68306, 68307, 68322, 68356], 68010, 68020 [68k, 68ec020], 68030 [68ec030], 68040 [68ec040], 68060 [68ec060], cpu32 [68330, 68331, 68332, 68333, 68334, 68336, 68340, 68341, 68349, 68360], fidoa [fido]) -- statement `sub.b %d1,%d3' ignored {standard input}:609: Error: invalid instruction for this architecture; needs 68020 or higher (68020 [68k, 68ec020], 68030 [68ec030], 68040 [68ec040], 68060 [68ec060]) -- statement `bfextu 4(%a1){%d0,#8},%d0' ignored {standard input}:752: Error: operands mismatch -- statement `mulu.l 4(%a0),%d3:%d0' ignored {standard input}:1155: Error: operands mismatch -- statement `divu.l %d0,%d3:%d7' ignored The math emulation support code is intended for 68020 and higher, and uses several instructions or instruction modes not available on coldfire or 68000. Originally, the dependency of M68KFPU_EMU on MMU was fine, as MMU support was only available on 68020 or higher. But this assumption was broken by the introduction of MMU support for M547x and M548x. Drop the dependency on MMU, as the code should work fine on 68020 and up without MMU (which are not yet supported by Linux, though). Add dependencies on M68KCLASSIC (to rule out Coldfire) and FPU (kernel has some type of floating-point support --- be it hardware or software emulated, to rule out anything below 68020). Fixes: 1f7034b9616e6f14 ("m68k: allow ColdFire 547x and 548x CPUs to be built with MMU enabled") Reported-by: kernel test robot <lkp@intel.com> Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org> Reviewed-by: Greg Ungerer <gerg@linux-m68k.org> Link: https://lore.kernel.org/r/18c34695b7c95107f60ccca82a4ff252f3edf477.1652446117.git.geert@linux-m68k.org
Diffstat (limited to 'arch/m68k/Kconfig.cpu')
-rw-r--r--arch/m68k/Kconfig.cpu2
1 files changed, 1 insertions, 1 deletions
diff --git a/arch/m68k/Kconfig.cpu b/arch/m68k/Kconfig.cpu
index 16ea9a67723c..3d5da25c73b5 100644
--- a/arch/m68k/Kconfig.cpu
+++ b/arch/m68k/Kconfig.cpu
@@ -327,7 +327,7 @@ comment "Processor Specific Options"
config M68KFPU_EMU
bool "Math emulation support"
- depends on MMU
+ depends on M68KCLASSIC && FPU
help
At some point in the future, this will cause floating-point math
instructions to be emulated by the kernel on machines that lack a