From d43a87d66039863b5a844361f096ec79f8fd2cb3 Mon Sep 17 00:00:00 2001 From: Geert Uytterhoeven Date: Fri, 13 May 2022 14:50:28 +0200 Subject: m68k: math-emu: Fix dependencies of math emulation support [ Upstream commit ed6bc6bf0a7d75e80eb1df883c09975ebb74e590 ] 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 Signed-off-by: Geert Uytterhoeven Reviewed-by: Greg Ungerer Link: https://lore.kernel.org/r/18c34695b7c95107f60ccca82a4ff252f3edf477.1652446117.git.geert@linux-m68k.org Signed-off-by: Sasha Levin --- arch/m68k/Kconfig.cpu | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/m68k/Kconfig.cpu b/arch/m68k/Kconfig.cpu index 60ac1cd8b96f..6bc7fc14163f 100644 --- a/arch/m68k/Kconfig.cpu +++ b/arch/m68k/Kconfig.cpu @@ -309,7 +309,7 @@ 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 -- cgit v1.2.3