Commit c760fc19 authored by Hyok S. Choi's avatar Hyok S. Choi Committed by Russell King
Browse files

[ARM] nommu: fixups for the exception vectors 



The high page vector (0xFFFF0000) does not supported in nommu mode.
This patch allows the vectors to be 0x00000000 or the begining of DRAM
in nommu mode.

Signed-off-by: default avatarHyok S. Choi <hyok.choi@samsung.com>
Signed-off-by: default avatarRussell King <rmk+kernel@arm.linux.org.uk>
parent f8c07de6

arch/arm/Kconfig

+8 −0
Original line number Diff line number Diff line
@@ -72,6 +72,14 @@ config FIQ 
config ARCH_MTD_XIP

	bool



config VECTORS_BASE

	hex

	default 0xffff0000 if MMU

	default DRAM_BASE if REMAP_VECTORS_TO_RAM

	default 0x00000000

	help

	  The base address of exception vectors.



source "init/Kconfig"



menu "System Type"

arch/arm/Kconfig-nommu

+17 −0
Original line number Diff line number Diff line
@@ -25,3 +25,20 @@ config FLASH_SIZE 
	hex 'FLASH Size' if SET_MEM_PARAM

	default 0x00400000



config REMAP_VECTORS_TO_RAM

	bool 'Install vectors to the begining of RAM' if DRAM_BASE

	depends on DRAM_BASE

	help

	  The kernel needs to change the hardware exception vectors.

	  In nommu mode, the hardware exception vectors are normally

	  placed at address 0x00000000. However, this region may be

	  occupied by read-only memory depending on H/W design.



	  If the region contains read-write memory, say 'n' here.



	  If your CPU provides a remap facility which allows the exception

	  vectors to be mapped to writable memory, say 'n' here.



	  Otherwise, say 'y' here.  In this case, the kernel will require

	  external support to redirect the hardware exception vectors to

	  the writable versions located at DRAM_BASE.

arch/arm/kernel/signal.h

+1 −1
Original line number Diff line number Diff line
@@ -7,6 +7,6 @@ 
 * it under the terms of the GNU General Public License version 2 as

 * published by the Free Software Foundation.

 */

#define KERN_SIGRETURN_CODE	0xffff0500

#define KERN_SIGRETURN_CODE	(CONFIG_VECTORS_BASE + 0x00000500)



extern const unsigned long sigreturn_codes[7];

arch/arm/kernel/traps.c

+5 −4
Original line number Diff line number Diff line
@@ -688,6 +688,7 @@ EXPORT_SYMBOL(abort); 


void __init trap_init(void)

{

	unsigned long vectors = CONFIG_VECTORS_BASE;

	extern char __stubs_start[], __stubs_end[];

	extern char __vectors_start[], __vectors_end[];

	extern char __kuser_helper_start[], __kuser_helper_end[];
@@ -698,9 +699,9 @@ void __init trap_init(void) 
	 * into the vector page, mapped at 0xffff0000, and ensure these

	 * are visible to the instruction stream.

	 */

	memcpy((void *)0xffff0000, __vectors_start, __vectors_end - __vectors_start);

	memcpy((void *)0xffff0200, __stubs_start, __stubs_end - __stubs_start);

	memcpy((void *)0xffff1000 - kuser_sz, __kuser_helper_start, kuser_sz);

	memcpy((void *)vectors, __vectors_start, __vectors_end - __vectors_start);

	memcpy((void *)vectors + 0x200, __stubs_start, __stubs_end - __stubs_start);

	memcpy((void *)vectors + 0x1000 - kuser_sz, __kuser_helper_start, kuser_sz);



	/*

	 * Copy signal return handlers into the vector page, and
@@ -709,6 +710,6 @@ void __init trap_init(void) 
	memcpy((void *)KERN_SIGRETURN_CODE, sigreturn_codes,

	       sizeof(sigreturn_codes));



	flush_icache_range(0xffff0000, 0xffff0000 + PAGE_SIZE);

	flush_icache_range(vectors, vectors + PAGE_SIZE);

	modify_domain(DOMAIN_USER, DOMAIN_CLIENT);

}