Commit 48927bbb authored by Jarkko Sakkinen's avatar Jarkko Sakkinen Committed by H. Peter Anvin
Browse files

x86, realmode: Move SMP trampoline to unified realmode code 



Migrated SMP trampoline code to the real mode blob.
SMP trampoline code is not yet removed from
.x86_trampoline because it is needed by the wakeup
code.

[ hpa: always enable compiling startup_32_smp in head_32.S... it is
  only a few instructions which go into .init on UP builds, and it makes
  the rest of the code less #ifdef ugly. ]

Signed-off-by: default avatarJarkko Sakkinen <jarkko.sakkinen@intel.com>
Link: http://lkml.kernel.org/r/1336501366-28617-6-git-send-email-jarkko.sakkinen@intel.com


Signed-off-by: default avatarH. Peter Anvin <hpa@linux.intel.com>
parent 5a8c9aeb

arch/x86/include/asm/realmode.h

+18 −0
Original line number Diff line number Diff line
@@ -12,6 +12,17 @@ struct real_mode_header { 
	/* reboot */

#ifdef CONFIG_X86_32

	u32	machine_real_restart_asm;

#endif

	/* SMP trampoline */

	u32	trampoline_data;

	u32	trampoline_status;

#ifdef CONFIG_X86_32

	u32	startup_32_smp;

	u32	boot_gdt;

#else

	u32	startup_64_smp;

	u32	level3_ident_pgt;

	u32	level3_kernel_pgt;

#endif

} __attribute__((__packed__));
@@ -25,6 +36,13 @@ extern unsigned long initial_gs; 
extern unsigned char real_mode_blob[];

extern unsigned char real_mode_relocs[];



#ifdef CONFIG_X86_32

extern unsigned char startup_32_smp[];

extern unsigned char boot_gdt[];

#else

extern unsigned char secondary_startup_64[];

#endif



extern void __init setup_real_mode(void);



#endif /* _ARCH_X86_REALMODE_H */

arch/x86/kernel/head_32.S

+1 −4
Original line number Diff line number Diff line
@@ -273,10 +273,7 @@ num_subarch_entries = (. - subarch_entries) / 4 
 * If cpu hotplug is not supported then this code can go in init section

 * which will be freed later

 */



__CPUINIT



#ifdef CONFIG_SMP

ENTRY(startup_32_smp)

	cld

	movl $(__BOOT_DS),%eax
@@ -287,7 +284,7 @@ ENTRY(startup_32_smp) 
	movl pa(stack_start),%ecx

	movl %eax,%ss

	leal -__PAGE_OFFSET(%ecx),%esp

#endif /* CONFIG_SMP */



default_entry:



/*

arch/x86/kernel/head_64.S

+0 −4
Original line number Diff line number Diff line
@@ -136,10 +136,6 @@ ident_complete: 
	/* Fixup phys_base */

	addq	%rbp, phys_base(%rip)



	/* Fixup trampoline */

	addq	%rbp, trampoline_level4_pgt + 0(%rip)

	addq	%rbp, trampoline_level4_pgt + (511*8)(%rip)



	/* Due to ENTRY(), sometimes the empty space gets filled with

	 * zeros. Better take a jmp than relying on empty space being

	 * filled with 0x90 (nop)

arch/x86/kernel/realmode.c

+14 −0
Original line number Diff line number Diff line
@@ -58,6 +58,20 @@ void __init setup_real_mode(void) 
	/* Copied header will contain relocated physical addresses. */

	memcpy(&real_mode_header, real_mode_base,

	       sizeof(struct real_mode_header));



#ifdef CONFIG_X86_32

	*((u32 *)__va(real_mode_header.startup_32_smp)) = __pa(startup_32_smp);

	*((u32 *)__va(real_mode_header.boot_gdt)) = __pa(boot_gdt);

#else

	*((u64 *) __va(real_mode_header.startup_64_smp)) =

		(u64) __pa(secondary_startup_64);



	*((u64 *) __va(real_mode_header.level3_ident_pgt)) =

		__pa(level3_ident_pgt) + _KERNPG_TABLE;



	*((u64 *) __va(real_mode_header.level3_kernel_pgt)) =

		__pa(level3_kernel_pgt) + _KERNPG_TABLE;

#endif

}



/*

arch/x86/kernel/smpboot.c

+10 −8
Original line number Diff line number Diff line
@@ -57,7 +57,7 @@ 
#include <asm/nmi.h>

#include <asm/irq.h>

#include <asm/idle.h>

#include <asm/trampoline.h>

#include <asm/realmode.h>

#include <asm/cpu.h>

#include <asm/numa.h>

#include <asm/pgtable.h>
@@ -73,6 +73,8 @@ 
#include <asm/smpboot_hooks.h>

#include <asm/i8259.h>



#include <asm/realmode.h>



/* State of each CPU */

DEFINE_PER_CPU(int, cpu_state) = { 0 };
@@ -662,8 +664,12 @@ static void __cpuinit announce_cpu(int cpu, int apicid) 
 */

static int __cpuinit do_boot_cpu(int apicid, int cpu)

{

	volatile u32 *trampoline_status =

		(volatile u32 *) __va(real_mode_header.trampoline_status);

	/* start_ip had better be page-aligned! */

	unsigned long start_ip = real_mode_header.trampoline_data;



	unsigned long boot_error = 0;

	unsigned long start_ip;

	int timeout;

	struct create_idle c_idle = {

		.cpu	= cpu,
@@ -713,9 +719,6 @@ do_rest: 
	initial_code = (unsigned long)start_secondary;

	stack_start  = c_idle.idle->thread.sp;



	/* start_ip had better be page-aligned! */

	start_ip = trampoline_address();



	/* So we see what's up */

	announce_cpu(cpu, apicid);
@@ -778,8 +781,7 @@ do_rest: 
			pr_debug("CPU%d: has booted.\n", cpu);

		} else {

			boot_error = 1;

			if (*(volatile u32 *)TRAMPOLINE_SYM(trampoline_status)

			    == 0xA5A5A5A5)

			if (*trampoline_status == 0xA5A5A5A5)

				/* trampoline started but...? */

				pr_err("CPU%d: Stuck ??\n", cpu);

			else
@@ -805,7 +807,7 @@ do_rest: 
	}



	/* mark "stuck" area as not stuck */

	*(volatile u32 *)TRAMPOLINE_SYM(trampoline_status) = 0;

	*trampoline_status = 0;



	if (get_uv_system_type() != UV_NON_UNIQUE_APIC) {

		/*

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