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| author |   Christophe Leroy <christophe.leroy@csgroup.eu> | 2022-07-11 16:19:30 +0200 |
|---|---|---|
| committer |   Michael Ellerman <mpe@ellerman.id.au> | 2022-07-27 21:36:06 +1000 |
| commit | 446cda1b21d9a6b3697fe399c6a3a00ff4a285f5 (patch) | |
| tree | dde0d63b5a96bc29aa017a8281b50240d13f86d2 /arch/powerpc/platforms | |
| parent | powerpc/32: Do not allow selection of e5500 or e6500 CPUs on PPC32 (diff) | |
| download | linux-dev-446cda1b21d9a6b3697fe399c6a3a00ff4a285f5.tar.xz linux-dev-446cda1b21d9a6b3697fe399c6a3a00ff4a285f5.zip | |
powerpc/32: Don't always pass -mcpu=powerpc to the compiler
Since commit 4bf4f42a2feb ("powerpc/kbuild: Set default generic
machine type for 32-bit compile"), when building a 32 bits kernel
with a bi-arch version of GCC, or when building a book3s/32 kernel,
the option -mcpu=powerpc is passed to GCC at all time, relying on it
being eventually overriden by a subsequent -mcpu=xxxx.
But when building the same kernel with a 32 bits only version of GCC,
that is not done, relying on gcc being built with the expected default
CPU.
This logic has two problems. First, it is a bit fragile to rely on
whether the GCC version is bi-arch or not, because today we can have
bi-arch versions of GCC configured with a 32 bits default. Second,
there are some versions of GCC which don't support -mcpu=powerpc,
for instance for e500 SPE-only versions.
So, stop relying on this approximative logic and allow the user to
decide whether he/she wants to use the toolchain's default CPU or if
he/she wants to set one, and allow only possible CPUs based on the
selected target.
Reported-by: Pali Rohár <pali@kernel.org>
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Tested-by: Pali Rohár <pali@kernel.org>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Segher Boessenkool <segher@kernel.crashing.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/d4df724691351531bf46d685d654689e5dfa0d74.1657549153.git.christophe.leroy@csgroup.eu
Diffstat (limited to 'arch/powerpc/platforms')
| -rw-r--r-- | arch/powerpc/platforms/Kconfig.cputype | 21 |
1 files changed, 18 insertions, 3 deletions
diff --git a/arch/powerpc/platforms/Kconfig.cputype b/arch/powerpc/platforms/Kconfig.cputype index 9805a2c717b9..bfea5d8452f8 100644 --- a/arch/powerpc/platforms/Kconfig.cputype +++ b/arch/powerpc/platforms/Kconfig.cputype @@ -135,9 +135,9 @@ config GENERIC_CPU select ARCH_HAS_FAST_MULTIPLIER select PPC_64S_HASH_MMU -config GENERIC_CPU +config POWERPC_CPU bool "Generic 32 bits powerpc" - depends on PPC32 && !PPC_8xx + depends on PPC32 && !PPC_8xx && !PPC_85xx config CELL_CPU bool "Cell Broadband Engine" @@ -196,11 +196,23 @@ config G4_CPU depends on PPC_BOOK3S_32 select ALTIVEC +config E500_CPU + bool "e500 (8540)" + depends on PPC_85xx && !PPC_E500MC + +config E500MC_CPU + bool "e500mc" + depends on PPC_85xx && PPC_E500MC + +config TOOLCHAIN_DEFAULT_CPU + bool "Rely on the toolchain's implicit default CPU" + depends on PPC32 + endchoice config TARGET_CPU_BOOL bool - default !GENERIC_CPU + default !GENERIC_CPU && !TOOLCHAIN_DEFAULT_CPU config TARGET_CPU string @@ -215,6 +227,9 @@ config TARGET_CPU default "e300c2" if E300C2_CPU default "e300c3" if E300C3_CPU default "G4" if G4_CPU + default "8540" if E500_CPU + default "e500mc" if E500MC_CPU + default "powerpc" if POWERPC_CPU config PPC_BOOK3S def_bool y |