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Commit 5085f3ff authored by Russell King's avatar Russell King
Browse files

ARM: hotplug cpu: Keep processor information, startup code & __lookup_processor_type 



When hotplug CPU is enabled, we need to keep the list of supported CPUs,
their setup functions, and __lookup_processor_type in place so that we
can find and initialize secondary CPUs.  Move these into the __CPUINIT
section.

Signed-off-by: default avatarRussell King <rmk+kernel@arm.linux.org.uk>
parent 37b05b63

arch/arm/kernel/head-common.S

+45 −36
Original line number Diff line number Diff line
@@ -145,45 +145,14 @@ ENDPROC(__error) 




/*

 * Read processor ID register (CP#15, CR0), and look up in the linker-built

 * supported processor list.  Note that we can't use the absolute addresses

 * for the __proc_info lists since we aren't running with the MMU on

 * (and therefore, we are not in the correct address space).  We have to

 * calculate the offset.

 *

 *	r9 = cpuid

 * Returns:

 *	r3, r4, r6 corrupted

 *	r5 = proc_info pointer in physical address space

 *	r9 = cpuid (preserved)

 */

__lookup_processor_type:

	adr	r3, 3f

	ldmia	r3, {r5 - r7}

	add	r3, r3, #8

	sub	r3, r3, r7			@ get offset between virt&phys

	add	r5, r5, r3			@ convert virt addresses to

	add	r6, r6, r3			@ physical address space

1:	ldmia	r5, {r3, r4}			@ value, mask

	and	r4, r4, r9			@ mask wanted bits

	teq	r3, r4

	beq	2f

	add	r5, r5, #PROC_INFO_SZ		@ sizeof(proc_info_list)

	cmp	r5, r6

	blo	1b

	mov	r5, #0				@ unknown processor

2:	mov	pc, lr

ENDPROC(__lookup_processor_type)



/*

 * This provides a C-API version of the above function.

 * This provides a C-API version of __lookup_processor_type

 */

ENTRY(lookup_processor_type)

	stmfd	sp!, {r4 - r7, r9, lr}

	stmfd	sp!, {r4 - r6, r9, lr}

	mov	r9, r0

	bl	__lookup_processor_type

	mov	r0, r5

	ldmfd	sp!, {r4 - r7, r9, pc}

	ldmfd	sp!, {r4 - r6, r9, pc}

ENDPROC(lookup_processor_type)



/*
@@ -191,8 +160,6 @@ ENDPROC(lookup_processor_type) 
 * more information about the __proc_info and __arch_info structures.

 */

	.align	2

3:	.long	__proc_info_begin

	.long	__proc_info_end

4:	.long	.

	.long	__arch_info_begin

	.long	__arch_info_end
@@ -265,3 +232,45 @@ __vet_atags: 
1:	mov	r2, #0

	mov	pc, lr

ENDPROC(__vet_atags)



/*

 * Read processor ID register (CP#15, CR0), and look up in the linker-built

 * supported processor list.  Note that we can't use the absolute addresses

 * for the __proc_info lists since we aren't running with the MMU on

 * (and therefore, we are not in the correct address space).  We have to

 * calculate the offset.

 *

 *	r9 = cpuid

 * Returns:

 *	r3, r4, r6 corrupted

 *	r5 = proc_info pointer in physical address space

 *	r9 = cpuid (preserved)

 */

	__CPUINIT

__lookup_processor_type:

	adr	r3, __lookup_processor_type_data

	ldmia	r3, {r4 - r6}

	sub	r3, r3, r4			@ get offset between virt&phys

	add	r5, r5, r3			@ convert virt addresses to

	add	r6, r6, r3			@ physical address space

1:	ldmia	r5, {r3, r4}			@ value, mask

	and	r4, r4, r9			@ mask wanted bits

	teq	r3, r4

	beq	2f

	add	r5, r5, #PROC_INFO_SZ		@ sizeof(proc_info_list)

	cmp	r5, r6

	blo	1b

	mov	r5, #0				@ unknown processor

2:	mov	pc, lr

ENDPROC(__lookup_processor_type)



/*

 * Look in <asm/procinfo.h> for information about the __proc_info structure.

 */

	.align	2

	.type	__lookup_processor_type_data, %object

__lookup_processor_type_data:

	.long	.

	.long	__proc_info_begin

	.long	__proc_info_end

	.size	__lookup_processor_type_data, . - __lookup_processor_type_data

arch/arm/kernel/vmlinux.lds.S

+17 −7
Original line number Diff line number Diff line
@@ -8,6 +8,19 @@ 
#include <asm/memory.h>

#include <asm/page.h>

	

#define PROC_INFO							\

	VMLINUX_SYMBOL(__proc_info_begin) = .;				\

	*(.proc.info.init)						\

	VMLINUX_SYMBOL(__proc_info_end) = .;



#ifdef CONFIG_HOTPLUG_CPU

#define ARM_CPU_DISCARD(x)

#define ARM_CPU_KEEP(x)		x

#else

#define ARM_CPU_DISCARD(x)	x

#define ARM_CPU_KEEP(x)

#endif



OUTPUT_ARCH(arm)

ENTRY(stext)
@@ -31,9 +44,7 @@ SECTIONS 
			HEAD_TEXT

			INIT_TEXT

		_einittext = .;

		__proc_info_begin = .;

			*(.proc.info.init)

		__proc_info_end = .;

		ARM_CPU_DISCARD(PROC_INFO)

		__arch_info_begin = .;

			*(.arch.info.init)

		__arch_info_end = .;
@@ -68,10 +79,8 @@ SECTIONS 
	/DISCARD/ : {

		*(.ARM.exidx.exit.text)

		*(.ARM.extab.exit.text)

#ifndef CONFIG_HOTPLUG_CPU

		*(.ARM.exidx.cpuexit.text)

		*(.ARM.extab.cpuexit.text)

#endif

		ARM_CPU_DISCARD(*(.ARM.exidx.cpuexit.text))

		ARM_CPU_DISCARD(*(.ARM.extab.cpuexit.text))

#ifndef CONFIG_HOTPLUG

		*(.ARM.exidx.devexit.text)

		*(.ARM.extab.devexit.text)
@@ -100,6 +109,7 @@ SECTIONS 
			*(.glue_7)

			*(.glue_7t)

		*(.got)			/* Global offset table		*/

			ARM_CPU_KEEP(PROC_INFO)

	}



	RO_DATA(PAGE_SIZE)

arch/arm/mm/proc-arm1020.S

+1 −1
Original line number Diff line number Diff line
@@ -430,7 +430,7 @@ ENTRY(cpu_arm1020_set_pte_ext) 
#endif /* CONFIG_MMU */

	mov	pc, lr



	__INIT

	__CPUINIT



	.type	__arm1020_setup, #function

__arm1020_setup:

arch/arm/mm/proc-arm1020e.S

+1 −1
Original line number Diff line number Diff line
@@ -412,7 +412,7 @@ ENTRY(cpu_arm1020e_set_pte_ext) 
#endif /* CONFIG_MMU */

	mov	pc, lr



	__INIT

	__CPUINIT



	.type	__arm1020e_setup, #function

__arm1020e_setup:

arch/arm/mm/proc-arm1022.S

+1 −1
Original line number Diff line number Diff line
@@ -394,7 +394,7 @@ ENTRY(cpu_arm1022_set_pte_ext) 
#endif /* CONFIG_MMU */

	mov	pc, lr



	__INIT

	__CPUINIT



	.type	__arm1022_setup, #function

__arm1022_setup: