Commit a591ede4 authored by Marc Zyngier's avatar Marc Zyngier Committed by Will Deacon
Browse files

arm64: Get rid of struct cpu_table 



struct cpu_table is an artifact left from the (very) early days of
the arm64 port, and its only real use is to allow the most beautiful
"AArch64 Processor" string to be displayed at boot time.

Really? Yes, really.

Let's get rid of it. In order to avoid another BogoMips-gate, the
aforementioned string is preserved.

Acked-by: default avatarMark Rutland <mark.rutland@arm.com>
Acked-by: default avatarCatalin Marinas <catalin.marinas@arm.com>
Acked-by: default avatarArd Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: default avatarMarc Zyngier <marc.zyngier@arm.com>
Signed-off-by: default avatarArd Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: default avatarWill Deacon <will.deacon@arm.com>
parent 62aa9655

arch/arm64/include/asm/cputable.h

deleted100644 → 0
+0 −30
Original line number Diff line number Diff line 
/*

 * arch/arm64/include/asm/cputable.h

 *

 * Copyright (C) 2012 ARM Ltd.

 *

 * This program is free software: you can redistribute it and/or modify

 * it under the terms of the GNU General Public License version 2 as

 * published by the Free Software Foundation.

 *

 * This program is distributed in the hope that it will be useful,

 * but WITHOUT ANY WARRANTY; without even the implied warranty of

 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

 * GNU General Public License for more details.

 *

 * You should have received a copy of the GNU General Public License

 * along with this program.  If not, see <http://www.gnu.org/licenses/>.

 */

#ifndef __ASM_CPUTABLE_H

#define __ASM_CPUTABLE_H



struct cpu_info {

	unsigned int	cpu_id_val;

	unsigned int	cpu_id_mask;

	const char	*cpu_name;

	unsigned long	(*cpu_setup)(void);

};



extern struct cpu_info *lookup_processor_type(unsigned int);



#endif

arch/arm64/kernel/Makefile

+1 −1
Original line number Diff line number Diff line
@@ -12,7 +12,7 @@ CFLAGS_REMOVE_insn.o = -pg 
CFLAGS_REMOVE_return_address.o = -pg



# Object file lists.

arm64-obj-y		:= cputable.o debug-monitors.o entry.o irq.o fpsimd.o	\

arm64-obj-y		:= debug-monitors.o entry.o irq.o fpsimd.o		\

			   entry-fpsimd.o process.o ptrace.o setup.o signal.o	\

			   sys.o stacktrace.o time.o traps.o io.o vdso.o	\

			   hyp-stub.o psci.o psci-call.o cpu_ops.o insn.o	\

arch/arm64/kernel/asm-offsets.c

+0 −4
Original line number Diff line number Diff line
@@ -24,7 +24,6 @@ 
#include <linux/kvm_host.h>

#include <asm/thread_info.h>

#include <asm/memory.h>

#include <asm/cputable.h>

#include <asm/smp_plat.h>

#include <asm/suspend.h>

#include <asm/vdso_datapage.h>
@@ -71,9 +70,6 @@ int main(void) 
  BLANK();

  DEFINE(PAGE_SZ,	       	PAGE_SIZE);

  BLANK();

  DEFINE(CPU_INFO_SZ,		sizeof(struct cpu_info));

  DEFINE(CPU_INFO_SETUP,	offsetof(struct cpu_info, cpu_setup));

  BLANK();

  DEFINE(DMA_BIDIRECTIONAL,	DMA_BIDIRECTIONAL);

  DEFINE(DMA_TO_DEVICE,		DMA_TO_DEVICE);

  DEFINE(DMA_FROM_DEVICE,	DMA_FROM_DEVICE);

arch/arm64/kernel/cputable.c

deleted100644 → 0
+0 −33
Original line number Diff line number Diff line 
/*

 * arch/arm64/kernel/cputable.c

 *

 * Copyright (C) 2012 ARM Ltd.

 *

 * This program is free software: you can redistribute it and/or modify

 * it under the terms of the GNU General Public License version 2 as

 * published by the Free Software Foundation.

 *

 * This program is distributed in the hope that it will be useful,

 * but WITHOUT ANY WARRANTY; without even the implied warranty of

 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

 * GNU General Public License for more details.

 *

 * You should have received a copy of the GNU General Public License

 * along with this program.  If not, see <http://www.gnu.org/licenses/>.

 */



#include <linux/init.h>



#include <asm/cputable.h>



extern unsigned long __cpu_setup(void);



struct cpu_info cpu_table[] = {

	{

		.cpu_id_val	= 0x000f0000,

		.cpu_id_mask	= 0x000f0000,

		.cpu_name	= "AArch64 Processor",

		.cpu_setup	= __cpu_setup,

	},

	{ /* Empty */ },

};

arch/arm64/kernel/head.S

+5 −71
Original line number Diff line number Diff line
@@ -245,22 +245,12 @@ ENTRY(stext) 
	bl	__calc_phys_offset		// x24=PHYS_OFFSET, x28=PHYS_OFFSET-PAGE_OFFSET

	bl	set_cpu_boot_mode_flag

	mrs	x22, midr_el1			// x22=cpuid

	mov	x0, x22

	bl	lookup_processor_type

	mov	x23, x0				// x23=current cpu_table

	/*

	 * __error_p may end up out of range for cbz if text areas are

	 * aligned up to section sizes.

	 */

	cbnz	x23, 1f				// invalid processor (x23=0)?

	b	__error_p

1:



	bl	__vet_fdt

	bl	__create_page_tables		// x25=TTBR0, x26=TTBR1

	/*

	 * The following calls CPU specific code in a position independent

	 * manner. See arch/arm64/mm/proc.S for details. x23 = base of

	 * cpu_info structure selected by lookup_processor_type above.

	 * The following calls CPU setup code, see arch/arm64/mm/proc.S for

	 * details.

	 * On return, the CPU will be ready for the MMU to be turned on and

	 * the TCR will have been set.

	 */
@@ -268,9 +258,7 @@ ENTRY(stext) 
						// MMU has been enabled

	adrp	lr, __enable_mmu		// return (PIC) address

	add	lr, lr, #:lo12:__enable_mmu

	ldr	x12, [x23, #CPU_INFO_SETUP]

	add	x12, x12, x28			// __virt_to_phys

	br	x12				// initialise processor

	b	__cpu_setup			// initialise processor

ENDPROC(stext)



/*
@@ -634,15 +622,9 @@ ENTRY(secondary_startup) 
	 * Common entry point for secondary CPUs.

	 */

	mrs	x22, midr_el1			// x22=cpuid

	mov	x0, x22

	bl	lookup_processor_type

	mov	x23, x0				// x23=current cpu_table

	cbz	x23, __error_p			// invalid processor (x23=0)?



	pgtbl	x25, x26, x28			// x25=TTBR0, x26=TTBR1

	ldr	x12, [x23, #CPU_INFO_SETUP]

	add	x12, x12, x28			// __virt_to_phys

	blr	x12				// initialise processor

	bl	__cpu_setup			// initialise processor



	ldr	x21, =secondary_data

	ldr	x27, =__secondary_switched	// address to jump to after enabling the MMU
@@ -708,51 +690,3 @@ ENDPROC(__calc_phys_offset) 
	.align 3

1:	.quad	.

	.quad	PAGE_OFFSET
 


/*

 * Exception handling. Something went wrong and we can't proceed. We ought to

 * tell the user, but since we don't have any guarantee that we're even

 * running on the right architecture, we do virtually nothing.

 */

__error_p:

ENDPROC(__error_p)



__error:

1:	nop

	b	1b

ENDPROC(__error)



/*

 * This function gets the processor ID in w0 and searches the cpu_table[] for

 * a match. It returns a pointer to the struct cpu_info it found. The

 * cpu_table[] must end with an empty (all zeros) structure.

 *

 * This routine can be called via C code and it needs to work with the MMU

 * both disabled and enabled (the offset is calculated automatically).

 */

ENTRY(lookup_processor_type)

	adr	x1, __lookup_processor_type_data

	ldp	x2, x3, [x1]

	sub	x1, x1, x2			// get offset between VA and PA

	add	x3, x3, x1			// convert VA to PA

1:

	ldp	w5, w6, [x3]			// load cpu_id_val and cpu_id_mask

	cbz	w5, 2f				// end of list?

	and	w6, w6, w0

	cmp	w5, w6

	b.eq	3f

	add	x3, x3, #CPU_INFO_SZ

	b	1b

2:

	mov	x3, #0				// unknown processor

3:

	mov	x0, x3

	ret

ENDPROC(lookup_processor_type)



	.align	3

	.type	__lookup_processor_type_data, %object

__lookup_processor_type_data:

	.quad	.

	.quad	cpu_table

	.size	__lookup_processor_type_data, . - __lookup_processor_type_data

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