Commit 8ff97fa3 authored by Russell King's avatar Russell King
Browse files

ARM: make the physical-relative calculation more obvious 



The physical-relative calculation between the XIP text and data sections
introduced by the previous patch was far from obvious. Let's simplify it
by turning it into a macro which takes the two (virtual) addresses.

This allows us to arrange the calculation in a more obvious manner - we
can make it two sub-expressions which calculate the physical address for
each symbol, and then takes the difference of those physical addresses.

Signed-off-by: default avatarRussell King <rmk+kernel@arm.linux.org.uk>
parent d7811455

arch/arm/include/asm/memory.h

+11 −4
Original line number Diff line number Diff line
@@ -135,11 +135,18 @@ 
#define PLAT_PHYS_OFFSET	UL(CONFIG_PHYS_OFFSET)



#ifdef CONFIG_XIP_KERNEL

#define PHYS_OFFSET_FIXUP \

	( XIP_VIRT_ADDR(CONFIG_XIP_PHYS_ADDR) - PAGE_OFFSET + \

	  PLAT_PHYS_OFFSET - CONFIG_XIP_PHYS_ADDR )

/*

 * When referencing data in RAM from the XIP region in a relative manner

 * with the MMU off, we need the relative offset between the two physical

 * addresses.  The macro below achieves this, which is:

 *    __pa(v_data) - __xip_pa(v_text)

 */

#define PHYS_RELATIVE(v_data, v_text) \

	(((v_data) - PAGE_OFFSET + PLAT_PHYS_OFFSET) - \

	 ((v_text) - XIP_VIRT_ADDR(CONFIG_XIP_PHYS_ADDR) + \

          CONFIG_XIP_PHYS_ADDR))

#else

#define PHYS_OFFSET_FIXUP 0

#define PHYS_RELATIVE(v_data, v_text) ((v_data) - (v_text))

#endif



#ifndef __ASSEMBLY__

arch/arm/mm/proc-v7.S

+1 −1
Original line number Diff line number Diff line
@@ -487,7 +487,7 @@ __errata_finish: 


	.align	2

__v7_setup_stack_ptr:

	.word	__v7_setup_stack - . + PHYS_OFFSET_FIXUP

	.word	PHYS_RELATIVE(__v7_setup_stack, .)

ENDPROC(__v7_setup)



	.bss

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