From 0350343ee6fdb253b901e30c7f23fcd17c64d342 Mon Sep 17 00:00:00 2001 From: Russell King Date: Fri, 8 Nov 2019 13:35:49 +0100 Subject: [PATCH] ARM: split out processor lookup Commit 65987a8553061515b5851b472081aedb9837a391 upstream. Split out the lookup of the processor type and associated error handling from the rest of setup_processor() - we will need to use this in the secondary CPU bringup path for big.Little Spectre variant 2 mitigation. Reviewed-by: Julien Thierry Signed-off-by: Russell King Signed-off-by: David A. Long Reviewed-by: Julien Thierry Signed-off-by: Sasha Levin Signed-off-by: Ard Biesheuvel Signed-off-by: Greg Kroah-Hartman --- arch/arm/include/asm/cputype.h | 1 + arch/arm/kernel/setup.c | 35 ++++++++++++++++++++-------------- 2 files changed, 22 insertions(+), 14 deletions(-) diff --git a/arch/arm/include/asm/cputype.h b/arch/arm/include/asm/cputype.h index 76bb3bd060d1..53125dad6edd 100644 --- a/arch/arm/include/asm/cputype.h +++ b/arch/arm/include/asm/cputype.h @@ -93,6 +93,7 @@ #define ARM_CPU_PART_SCORPION 0x510002d0 extern unsigned int processor_id; +struct proc_info_list *lookup_processor(u32 midr); #ifdef CONFIG_CPU_CP15 #define read_cpuid(reg) \ diff --git a/arch/arm/kernel/setup.c b/arch/arm/kernel/setup.c index 20edd349d379..5aa9c08de410 100644 --- a/arch/arm/kernel/setup.c +++ b/arch/arm/kernel/setup.c @@ -599,21 +599,28 @@ static void __init smp_build_mpidr_hash(void) } #endif +/* + * locate processor in the list of supported processor types. The linker + * builds this table for us from the entries in arch/arm/mm/proc-*.S + */ +struct proc_info_list *lookup_processor(u32 midr) +{ + struct proc_info_list *list = lookup_processor_type(midr); + + if (!list) { + pr_err("CPU%u: configuration botched (ID %08x), CPU halted\n", + smp_processor_id(), midr); + while (1) + /* can't use cpu_relax() here as it may require MMU setup */; + } + + return list; +} + static void __init setup_processor(void) { - struct proc_info_list *list; - - /* - * locate processor in the list of supported processor - * types. The linker builds this table for us from the - * entries in arch/arm/mm/proc-*.S - */ - list = lookup_processor_type(read_cpuid_id()); - if (!list) { - pr_err("CPU configuration botched (ID %08x), unable to continue.\n", - read_cpuid_id()); - while (1); - } + unsigned int midr = read_cpuid_id(); + struct proc_info_list *list = lookup_processor(midr); cpu_name = list->cpu_name; __cpu_architecture = __get_cpu_architecture(); @@ -632,7 +639,7 @@ static void __init setup_processor(void) #endif pr_info("CPU: %s [%08x] revision %d (ARMv%s), cr=%08lx\n", - cpu_name, read_cpuid_id(), read_cpuid_id() & 15, + list->cpu_name, midr, midr & 15, proc_arch[cpu_architecture()], get_cr()); snprintf(init_utsname()->machine, __NEW_UTS_LEN + 1, "%s%c",