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| author | Geert Uytterhoeven <geert@linux-m68k.org> | 2022-05-13 14:50:28 +0200 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2022-06-14 18:11:37 +0200 |
| commit | d43a87d66039863b5a844361f096ec79f8fd2cb3 (patch) | |
| tree | 716db482003c653fcde769c329105f102e01ccce | |
| parent | 6f55fac0af3531cf60d11369454c41f5fc81ab3f (diff) | |
| download | linux-stable-d43a87d66039863b5a844361f096ec79f8fd2cb3.tar.gz linux-stable-d43a87d66039863b5a844361f096ec79f8fd2cb3.tar.bz2 linux-stable-d43a87d66039863b5a844361f096ec79f8fd2cb3.zip | |
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 <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
Signed-off-by: Sasha Levin <sashal@kernel.org>
| -rw-r--r-- | arch/m68k/Kconfig.cpu | 2 |
1 files changed, 1 insertions, 1 deletions
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 |