Commit a91da545 authored by Linus Walleij's avatar Linus Walleij Committed by Russell King (Oracle)
Browse files

ARM: 9089/1: Define kernel physical section start and end 



When we are mapping the initial sections in head.S we
know very well where the start and end of the kernel image
in physical memory is placed. Later on it gets hard
to determine this.

Save the information into two variables named
kernel_sec_start and kernel_sec_end for convenience
for later work involving the physical start and end
of the kernel. These variables are section-aligned
corresponding to the early section mappings set up
in head.S.

Signed-off-by: default avatarLinus Walleij <linus.walleij@linaro.org>
Signed-off-by: default avatarRussell King <rmk+kernel@armlinux.org.uk>
parent b78f63f4

arch/arm/include/asm/memory.h

+7 −0
Original line number Diff line number Diff line
@@ -158,6 +158,13 @@ extern unsigned long vectors_base; 


#ifndef __ASSEMBLY__



/*

 * Physical start and end address of the kernel sections. These addresses are

 * 2MB-aligned to match the section mappings placed over the kernel.

 */

extern phys_addr_t kernel_sec_start;

extern phys_addr_t kernel_sec_end;



/*

 * Physical vs virtual RAM address space conversion.  These are

 * private definitions which should NOT be used outside memory.h

arch/arm/kernel/head.S

+24 −3
Original line number Diff line number Diff line
@@ -47,6 +47,20 @@ 
	.globl	swapper_pg_dir

	.equ	swapper_pg_dir, KERNEL_RAM_VADDR - PG_DIR_SIZE



	/*

	 * This needs to be assigned at runtime when the linker symbols are

	 * resolved.

	 */

	.pushsection .data

	.align	2

	.globl	kernel_sec_start

	.globl	kernel_sec_end

kernel_sec_start:

	.long	0

kernel_sec_end:

	.long	0

	.popsection



	.macro	pgtbl, rd, phys

	add	\rd, \phys, #TEXT_OFFSET

	sub	\rd, \rd, #PG_DIR_SIZE
@@ -229,16 +243,23 @@ __create_page_tables: 
	blo	1b



	/*

	 * Map our RAM from the start to the end of the kernel .bss section.

	 * The main matter: map in the kernel using section mappings, and

	 * set two variables to indicate the physical start and end of the

	 * kernel.

	 */

	add	r0, r4, #PAGE_OFFSET >> (SECTION_SHIFT - PMD_ORDER)

	add	r0, r4, #KERNEL_OFFSET >> (SECTION_SHIFT - PMD_ORDER)

	ldr	r6, =(_end - 1)

	orr	r3, r8, r7

	adr_l	r5, kernel_sec_start		@ _pa(kernel_sec_start)

	str	r8, [r5]			@ Save physical start of kernel

	orr	r3, r8, r7			@ Add the MMU flags

	add	r6, r4, r6, lsr #(SECTION_SHIFT - PMD_ORDER)

1:	str	r3, [r0], #1 << PMD_ORDER

	add	r3, r3, #1 << SECTION_SHIFT

	cmp	r0, r6

	bls	1b

	eor	r3, r3, r7			@ Remove the MMU flags

	adr_l	r5, kernel_sec_end		@ _pa(kernel_sec_end)

	str	r3, [r5]			@ Save physical end of kernel



#ifdef CONFIG_XIP_KERNEL

	/*