Commit 65987a85 authored by Russell King's avatar Russell King
Browse files

ARM: split out processor lookup 



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: default avatarJulien Thierry <julien.thierry@arm.com>
Signed-off-by: default avatarRussell King <rmk+kernel@armlinux.org.uk>
parent 899a42f8

arch/arm/include/asm/cputype.h

+1 −0
Original line number Diff line number Diff line
@@ -107,6 +107,7 @@ 
#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)							\

arch/arm/kernel/setup.c

+19 −12
Original line number Diff line number Diff line
@@ -667,22 +667,29 @@ static void __init smp_build_mpidr_hash(void) 
}

#endif



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

 * 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());

struct proc_info_list *lookup_processor(u32 midr)

{

	struct proc_info_list *list = lookup_processor_type(midr);



	if (!list) {

		pr_err("CPU configuration botched (ID %08x), unable to continue.\n",

		       read_cpuid_id());

		while (1);

		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)

{

	unsigned int midr = read_cpuid_id();

	struct proc_info_list *list = lookup_processor(midr);



	cpu_name = list->cpu_name;

	__cpu_architecture = __get_cpu_architecture();
@@ -700,7 +707,7 @@ 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",

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