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Commit 00945010 authored by Russell King's avatar Russell King
Browse files

ARM: hotplug cpu: move secondary_startup, __enable_mmu to cpuinit 



Move these two functions, both of which are required for secondary
CPU booting, into the cpuinit section.  Ensure bad processors call
__error_p for better diagnostics, rather than just __error.

Signed-off-by: default avatarRussell King <rmk+kernel@arm.linux.org.uk>
parent 786f1b73

arch/arm/kernel/head.S

+104 −102
Original line number Diff line number Diff line
@@ -97,114 +97,14 @@ ENTRY(stext) 
	 */

	ldr	r13, =__mmap_switched		@ address to jump to after

						@ mmu has been enabled

	adr	lr, BSYM(__enable_mmu)		@ return (PIC) address

	adr	lr, BSYM(1f)			@ return (PIC) address

 ARM(	add	pc, r10, #PROCINFO_INITFUNC	)

 THUMB(	add	r12, r10, #PROCINFO_INITFUNC	)

 THUMB(	mov	pc, r12				)

1:	b	__enable_mmu

ENDPROC(stext)

	.ltorg



#if defined(CONFIG_SMP)

ENTRY(secondary_startup)

	/*

	 * Common entry point for secondary CPUs.

	 *

	 * Ensure that we're in SVC mode, and IRQs are disabled.  Lookup

	 * the processor type - there is no need to check the machine type

	 * as it has already been validated by the primary processor.

	 */

	setmode	PSR_F_BIT | PSR_I_BIT | SVC_MODE, r9

	mrc	p15, 0, r9, c0, c0		@ get processor id

	bl	__lookup_processor_type

	movs	r10, r5				@ invalid processor?

	moveq	r0, #'p'			@ yes, error 'p'

	beq	__error



	/*

	 * Use the page tables supplied from  __cpu_up.

	 */

	adr	r4, __secondary_data

	ldmia	r4, {r5, r7, r12}		@ address to jump to after

	sub	r4, r4, r5			@ mmu has been enabled

	ldr	r4, [r7, r4]			@ get secondary_data.pgdir

	adr	lr, BSYM(__enable_mmu)		@ return address

	mov	r13, r12			@ __secondary_switched address

 ARM(	add	pc, r10, #PROCINFO_INITFUNC	) @ initialise processor

						  @ (return control reg)

 THUMB(	add	r12, r10, #PROCINFO_INITFUNC	)

 THUMB(	mov	pc, r12				)

ENDPROC(secondary_startup)



	/*

	 * r6  = &secondary_data

	 */

ENTRY(__secondary_switched)

	ldr	sp, [r7, #4]			@ get secondary_data.stack

	mov	fp, #0

	b	secondary_start_kernel

ENDPROC(__secondary_switched)



	.type	__secondary_data, %object

__secondary_data:

	.long	.

	.long	secondary_data

	.long	__secondary_switched

#endif /* defined(CONFIG_SMP) */







/*

 * Setup common bits before finally enabling the MMU.  Essentially

 * this is just loading the page table pointer and domain access

 * registers.

 */

__enable_mmu:

#ifdef CONFIG_ALIGNMENT_TRAP

	orr	r0, r0, #CR_A

#else

	bic	r0, r0, #CR_A

#endif

#ifdef CONFIG_CPU_DCACHE_DISABLE

	bic	r0, r0, #CR_C

#endif

#ifdef CONFIG_CPU_BPREDICT_DISABLE

	bic	r0, r0, #CR_Z

#endif

#ifdef CONFIG_CPU_ICACHE_DISABLE

	bic	r0, r0, #CR_I

#endif

	mov	r5, #(domain_val(DOMAIN_USER, DOMAIN_MANAGER) | \

		      domain_val(DOMAIN_KERNEL, DOMAIN_MANAGER) | \

		      domain_val(DOMAIN_TABLE, DOMAIN_MANAGER) | \

		      domain_val(DOMAIN_IO, DOMAIN_CLIENT))

	mcr	p15, 0, r5, c3, c0, 0		@ load domain access register

	mcr	p15, 0, r4, c2, c0, 0		@ load page table pointer

	b	__turn_mmu_on

ENDPROC(__enable_mmu)



/*

 * Enable the MMU.  This completely changes the structure of the visible

 * memory space.  You will not be able to trace execution through this.

 * If you have an enquiry about this, *please* check the linux-arm-kernel

 * mailing list archives BEFORE sending another post to the list.

 *

 *  r0  = cp#15 control register

 *  r13 = *virtual* address to jump to upon completion

 *

 * other registers depend on the function called upon completion

 */

	.align	5

__turn_mmu_on:

	mov	r0, r0

	mcr	p15, 0, r0, c1, c0, 0		@ write control reg

	mrc	p15, 0, r3, c0, c0, 0		@ read id reg

	mov	r3, r3

	mov	r3, r13

	mov	pc, r3

__enable_mmu_end:

ENDPROC(__turn_mmu_on)





/*

 * Setup the initial page tables.  We only setup the barest

 * amount which are required to get the kernel running, which
@@ -349,4 +249,106 @@ __enable_mmu_loc: 
	.long	__enable_mmu

	.long	__enable_mmu_end



#if defined(CONFIG_SMP)

	__CPUINIT

ENTRY(secondary_startup)

	/*

	 * Common entry point for secondary CPUs.

	 *

	 * Ensure that we're in SVC mode, and IRQs are disabled.  Lookup

	 * the processor type - there is no need to check the machine type

	 * as it has already been validated by the primary processor.

	 */

	setmode	PSR_F_BIT | PSR_I_BIT | SVC_MODE, r9

	mrc	p15, 0, r9, c0, c0		@ get processor id

	bl	__lookup_processor_type

	movs	r10, r5				@ invalid processor?

	moveq	r0, #'p'			@ yes, error 'p'

	beq	__error_p



	/*

	 * Use the page tables supplied from  __cpu_up.

	 */

	adr	r4, __secondary_data

	ldmia	r4, {r5, r7, r12}		@ address to jump to after

	sub	r4, r4, r5			@ mmu has been enabled

	ldr	r4, [r7, r4]			@ get secondary_data.pgdir

	adr	lr, BSYM(__enable_mmu)		@ return address

	mov	r13, r12			@ __secondary_switched address

 ARM(	add	pc, r10, #PROCINFO_INITFUNC	) @ initialise processor

						  @ (return control reg)

 THUMB(	add	r12, r10, #PROCINFO_INITFUNC	)

 THUMB(	mov	pc, r12				)

ENDPROC(secondary_startup)



	/*

	 * r6  = &secondary_data

	 */

ENTRY(__secondary_switched)

	ldr	sp, [r7, #4]			@ get secondary_data.stack

	mov	fp, #0

	b	secondary_start_kernel

ENDPROC(__secondary_switched)



	.type	__secondary_data, %object

__secondary_data:

	.long	.

	.long	secondary_data

	.long	__secondary_switched

#endif /* defined(CONFIG_SMP) */







/*

 * Setup common bits before finally enabling the MMU.  Essentially

 * this is just loading the page table pointer and domain access

 * registers.

 */

__enable_mmu:

#ifdef CONFIG_ALIGNMENT_TRAP

	orr	r0, r0, #CR_A

#else

	bic	r0, r0, #CR_A

#endif

#ifdef CONFIG_CPU_DCACHE_DISABLE

	bic	r0, r0, #CR_C

#endif

#ifdef CONFIG_CPU_BPREDICT_DISABLE

	bic	r0, r0, #CR_Z

#endif

#ifdef CONFIG_CPU_ICACHE_DISABLE

	bic	r0, r0, #CR_I

#endif

	mov	r5, #(domain_val(DOMAIN_USER, DOMAIN_MANAGER) | \

		      domain_val(DOMAIN_KERNEL, DOMAIN_MANAGER) | \

		      domain_val(DOMAIN_TABLE, DOMAIN_MANAGER) | \

		      domain_val(DOMAIN_IO, DOMAIN_CLIENT))

	mcr	p15, 0, r5, c3, c0, 0		@ load domain access register

	mcr	p15, 0, r4, c2, c0, 0		@ load page table pointer

	b	__turn_mmu_on

ENDPROC(__enable_mmu)



/*

 * Enable the MMU.  This completely changes the structure of the visible

 * memory space.  You will not be able to trace execution through this.

 * If you have an enquiry about this, *please* check the linux-arm-kernel

 * mailing list archives BEFORE sending another post to the list.

 *

 *  r0  = cp#15 control register

 *  r13 = *virtual* address to jump to upon completion

 *

 * other registers depend on the function called upon completion

 */

	.align	5

__turn_mmu_on:

	mov	r0, r0

	mcr	p15, 0, r0, c1, c0, 0		@ write control reg

	mrc	p15, 0, r3, c0, c0, 0		@ read id reg

	mov	r3, r3

	mov	r3, r13

	mov	pc, r3

__enable_mmu_end:

ENDPROC(__turn_mmu_on)





#include "head-common.S"