Merge branch 'swp' (early part) into for-next (c89c3a6a) · Commits · e / devices / android_kernel_fairphone_FP4

arch/arm/kernel/setup.c

+22 −7

Original line number	Diff line number	Diff line
		@@ -393,19 +393,34 @@ static void __init cpuid_init_hwcaps(void)
		elf_hwcap \|= HWCAP_LPAE;
		}

		static void __init feat_v6_fixup(void)
		static void __init elf_hwcap_fixup(void)
		{
		int id = read_cpuid_id();

		if ((id & 0xff0f0000) != 0x41070000)
		return;
		unsigned id = read_cpuid_id();
		unsigned sync_prim;

		/*
		* HWCAP_TLS is available only on 1136 r1p0 and later,
		* see also kuser_get_tls_init.
		*/
		if ((((id >> 4) & 0xfff) == 0xb36) && (((id >> 20) & 3) == 0))
		if (read_cpuid_part() == ARM_CPU_PART_ARM1136 &&
		((id >> 20) & 3) == 0) {
		elf_hwcap &= ~HWCAP_TLS;
		return;
		}

		/* Verify if CPUID scheme is implemented */
		if ((id & 0x000f0000) != 0x000f0000)
		return;

		/*
		* If the CPU supports LDREX/STREX and LDREXB/STREXB,
		* avoid advertising SWP; it may not be atomic with
		* multiprocessing cores.
		*/
		sync_prim = ((read_cpuid_ext(CPUID_EXT_ISAR3) >> 8) & 0xf0) \|
		((read_cpuid_ext(CPUID_EXT_ISAR4) >> 20) & 0x0f);
		if (sync_prim >= 0x13)
		elf_hwcap &= ~HWCAP_SWP;
		}

		/*
		@@ -609,7 +624,7 @@ static void __init setup_processor(void)
		#endif
		erratum_a15_798181_init();

		feat_v6_fixup();
		elf_hwcap_fixup();

		cacheid_init();
		cpu_init();

+4 −0

Original line number	Diff line number	Diff line
		@@ -27,6 +27,7 @@
		#include <linux/perf_event.h>

		#include <asm/opcodes.h>
		#include <asm/system_info.h>
		#include <asm/traps.h>
		#include <asm/uaccess.h>

		@@ -266,6 +267,9 @@ static struct undef_hook swp_hook = {
		*/
		static int __init swp_emulation_init(void)
		{
		if (cpu_architecture() < CPU_ARCH_ARMv7)
		return 0;

		#ifdef CONFIG_PROC_FS
		if (!proc_create("cpu/swp_emulation", S_IRUGO, NULL, &proc_status_fops))
		return -ENOMEM;

+1 −1

Original line number	Diff line number	Diff line
		@@ -669,7 +669,7 @@ config ARM_VIRT_EXT
		details.

		config SWP_EMULATE
		bool "Emulate SWP/SWPB instructions"
		bool "Emulate SWP/SWPB instructions" if !SMP
		depends on CPU_V7
		default y if SMP
		select HAVE_PROC_CPU if PROC_FS