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| author | Nicholas Piggin <npiggin@gmail.com> | 2023-04-08 05:17:49 +0300 |
|---|---|---|
| committer | Michael Ellerman <mpe@ellerman.id.au> | 2023-04-20 05:54:22 +0300 |
| commit | dc5dac748af9087e9240bd2ae6ae7db48d5360ae (patch) | |
| tree | 59998f55199668c054226f3bc29fc4963fc35741 /arch/powerpc/platforms | |
| parent | b270bebd34e36fb69363d65e24b00a9d148903e8 (diff) | |
| download | linux-dc5dac748af9087e9240bd2ae6ae7db48d5360ae.tar.xz | |
powerpc/64: Add support to build with prefixed instructions
Add an option to build kernel and module with prefixed instructions if
the CPU and toolchain support it.
This is not related to kernel support for userspace execution of
prefixed instructions.
Building with prefixed instructions breaks some extended inline asm
memory addressing, for example it will provide immediates that exceed
the range of simple load/store displacement. Whether this is a
toolchain or a kernel asm problem remains to be seen. For now, these
are replaced with simpler and less efficient direct register addressing
when compiling with prefixed.
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20230408021752.862660-4-npiggin@gmail.com
Diffstat (limited to 'arch/powerpc/platforms')
| -rw-r--r-- | arch/powerpc/platforms/Kconfig.cputype | 20 |
1 files changed, 20 insertions, 0 deletions
diff --git a/arch/powerpc/platforms/Kconfig.cputype b/arch/powerpc/platforms/Kconfig.cputype index 046b571496b1..1ff0d2818da6 100644 --- a/arch/powerpc/platforms/Kconfig.cputype +++ b/arch/powerpc/platforms/Kconfig.cputype @@ -180,6 +180,7 @@ config POWER10_CPU bool "POWER10" depends on PPC_BOOK3S_64 select ARCH_HAS_FAST_MULTIPLIER + select PPC_HAVE_PREFIXED_SUPPORT config E5500_CPU bool "Freescale e5500" @@ -454,6 +455,22 @@ config PPC_RADIX_MMU_DEFAULT If you're unsure, say Y. +config PPC_KERNEL_PREFIXED + depends on PPC_HAVE_PREFIXED_SUPPORT + depends on CC_HAS_PREFIXED + default n + bool "Build Kernel with Prefixed Instructions" + help + POWER10 and later CPUs support prefixed instructions, 8 byte + instructions that include large immediate, pc relative addressing, + and various floating point, vector, MMA. + + This option builds the kernel with prefixed instructions, and + allows a pc relative addressing option to be selected. + + Kernel support for prefixed instructions in applications and guests + is not affected by this option. + config PPC_KUEP bool "Kernel Userspace Execution Prevention" if !40x default y if !40x @@ -490,6 +507,9 @@ config PPC_MMU_NOHASH config PPC_HAVE_PMU_SUPPORT bool +config PPC_HAVE_PREFIXED_SUPPORT + bool + config PMU_SYSFS bool "Create PMU SPRs sysfs file" default n |