On Tue, Nov 24, 2015 at 12:53:49AM -0800, Stephen Boyd wrote: > On 11/23, Stephen Boyd wrote: > > On 11/23, Arnd Bergmann wrote: > > > > > > Ok, thanks for the confirmation. > > > > > > Summarizing what we've found, I think we can get away with just > > > introducing two Kconfig symbols ARCH_MULTI_V7VE and CPU_V7VE. > > > Most CPUs fall clearly into one category or the other, and then > > > we can allow LPAE to be selected for V7VE-only build but not > > > for plain V7, and we can unconditionally build the kernel with > > > > > > arch-$(CONFIG_CPU_32v7VE) = -D__LINUX_ARM_ARCH__=7 $(call cc-option,-march=armv7ve,-march=armv7-a -mcpu=cortex-a15) > > > > > > > This causes compiler spew for me: > > > > warning: switch -mcpu=cortex-a15 conflicts with -march=armv7-a switch > > > > Removing -march=armv7-a from there makes it quiet. > > > > Also, it's sort of feels wrong to have -mcpu in a place where > > we're exclusively doing -march. Perhaps the fallback should be > > bog standard -march=armv7-a? (or the fallback for that one > > "-march=armv5t -Wa$(comma)-march=armv7-a")? > > > > And adding CPU_V7VE causes a cascade of changes to wherever > CPU_V7 is being used today. Here's the patch I currently have, > without the platform changes: > > ---8<---- > arch/arm/Kconfig | 68 +++++++++++++++++++++----------------- > arch/arm/Kconfig-nommu | 2 +- > arch/arm/Makefile | 1 + > arch/arm/boot/compressed/head.S | 2 +- > arch/arm/boot/compressed/misc.c | 2 +- > arch/arm/include/asm/cacheflush.h | 2 +- > arch/arm/include/asm/glue-cache.h | 2 +- > arch/arm/include/asm/glue-proc.h | 2 +- > arch/arm/include/asm/switch_to.h | 2 +- > arch/arm/include/debug/icedcc.S | 2 +- > arch/arm/kernel/entry-armv.S | 6 ++-- > arch/arm/kernel/perf_event_v7.c | 4 +-- > arch/arm/kvm/Kconfig | 2 +- > arch/arm/mm/Kconfig | 41 ++++++++++++++++------- > arch/arm/mm/Makefile | 1 + > arch/arm/probes/kprobes/test-arm.c | 2 +- > drivers/bus/Kconfig | 6 ++-- > 17 files changed, 86 insertions(+), 61 deletions(-) > > diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig > index 9e2d2adcc85b..ccd0d5553d38 100644 > --- a/arch/arm/Kconfig > +++ b/arch/arm/Kconfig > @@ -32,7 +32,7 @@ config ARM > select HANDLE_DOMAIN_IRQ > select HARDIRQS_SW_RESEND > select HAVE_ARCH_AUDITSYSCALL if (AEABI && !OABI_COMPAT) > - select HAVE_ARCH_BITREVERSE if (CPU_32v7M || CPU_32v7) && !CPU_32v6 > + select HAVE_ARCH_BITREVERSE if (CPU_32v7M || CPU_32v7 || CPU_32_v7VE) && !CPU_32v6 > select HAVE_ARCH_JUMP_LABEL if !XIP_KERNEL && !CPU_ENDIAN_BE32 > select HAVE_ARCH_KGDB if !CPU_ENDIAN_BE32 > select HAVE_ARCH_SECCOMP_FILTER if (AEABI && !OABI_COMPAT) > @@ -46,12 +46,12 @@ config ARM > select HAVE_DMA_ATTRS > select HAVE_DMA_CONTIGUOUS if MMU > select HAVE_DYNAMIC_FTRACE if (!XIP_KERNEL) && !CPU_ENDIAN_BE32 > - select HAVE_EFFICIENT_UNALIGNED_ACCESS if (CPU_V6 || CPU_V6K || CPU_V7) && MMU > + select HAVE_EFFICIENT_UNALIGNED_ACCESS if (CPU_V6 || CPU_V6K || CPU_V7 || CPU_V7VE) && MMU > select HAVE_FTRACE_MCOUNT_RECORD if (!XIP_KERNEL) > select HAVE_FUNCTION_GRAPH_TRACER if (!THUMB2_KERNEL) > select HAVE_FUNCTION_TRACER if (!XIP_KERNEL) > select HAVE_GENERIC_DMA_COHERENT > - select HAVE_HW_BREAKPOINT if (PERF_EVENTS && (CPU_V6 || CPU_V6K || CPU_V7)) > + select HAVE_HW_BREAKPOINT if (PERF_EVENTS && (CPU_V6 || CPU_V6K || CPU_V7 || CPU_V7VE)) > select HAVE_IDE if PCI || ISA || PCMCIA > select HAVE_IRQ_TIME_ACCOUNTING > select HAVE_KERNEL_GZIP > @@ -805,6 +805,12 @@ config ARCH_MULTI_V7 > select CPU_V7 > select HAVE_SMP > > +config ARCH_MULTI_V7VE > + bool "ARMv7 w/ virtualization extensions based platforms (Cortex-A, PJ4-MP, Krait)" > + select ARCH_MULTI_V6_V7 > + select CPU_V7VE > + select HAVE_SMP > + > config ARCH_MULTI_V6_V7 > bool > select MIGHT_HAVE_CACHE_L2X0 > @@ -1069,7 +1075,7 @@ config ARM_ERRATA_411920 > > config ARM_ERRATA_430973 > bool "ARM errata: Stale prediction on replaced interworking branch" > - depends on CPU_V7 > + depends on CPU_V7 || CPU_V7VE NAK on all this. The fact that you're having to add CPU_V7VE at all sites which have CPU_V7 shows that this is a totally broken way of approaching this. Make CPU_V7VE be an _add-on_ to CPU_V7. In other words, when CPU_V7VE is enabled, CPU_V7 should also be enabled, just like we do for CPU_V6K. Note that v7M is different because that's not an add-on feature, it's a different CPU class from (what should be) v7A. -- FTTC broadband for 0.8mile line: currently at 9.6Mbps down 400kbps up according to speedtest.net. -- To unsubscribe from this list: send the line "unsubscribe linux-arm-msm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
