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ARM: mach-imx: move early resume code out of the .data section 

Building the kernel with allyesconfig fails because the i.mx early
resume code located in the .data section is unable to fixup the bl
relocation as the branch target gets too far away.

The idea of having code in the .data section allows for easy access to
nearby data using relative addressing while the MMU is off. However it
is probably best to move the code back to the .text section where it
belongs and fixup the data access instead.  This solves the bl reloc
issue (at least until this becomes a general problem) and simplifies
the code as well.

Signed-off-by: Nicolas Pitre <nico@linaro.org>
Signed-off-by: Shawn Guo <shawn.guo@linaro.org>
This commit is contained in:
Nicolas Pitre 2013-02-18 23:11:30 -05:00 committed by Shawn Guo
parent 6dbe51c251
commit b4e6153704
2 changed files with 9 additions and 24 deletions
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18
arch/arm/mach-imx/headsmp.S
View File

@ -26,16 +26,16 @@ ENDPROC(v7_secondary_startup)
#ifdef CONFIG_PM
/*
* The following code is located into the .data section. This is to
* allow phys_l2x0_saved_regs to be accessed with a relative load
* as we are running on physical address here.
* The following code must assume it is running from physical address
* where absolute virtual addresses to the data section have to be
* turned into relative ones.
*/
.data
.align
#ifdef CONFIG_CACHE_L2X0
.macro pl310_resume
ldr r2, phys_l2x0_saved_regs
adr r0, l2x0_saved_regs_offset
ldr r2, [r0]
add r2, r2, r0
ldr r0, [r2, #L2X0_R_PHY_BASE] @ get physical base of l2x0
ldr r1, [r2, #L2X0_R_AUX_CTRL] @ get aux_ctrl value
str r1, [r0, #L2X0_AUX_CTRL] @ restore aux_ctrl
@ -43,9 +43,9 @@ ENDPROC(v7_secondary_startup)
str r1, [r0, #L2X0_CTRL] @ re-enable L2
.endm
.globl phys_l2x0_saved_regs
phys_l2x0_saved_regs:
.long 0
l2x0_saved_regs_offset:
.word l2x0_saved_regs - .
#else
.macro pl310_resume
.endm

15
arch/arm/mach-imx/pm-imx6q.c
View File

@ -22,8 +22,6 @@
#include "common.h"
#include "hardware.h"
extern unsigned long phys_l2x0_saved_regs;
static int imx6q_suspend_finish(unsigned long val)
{
cpu_do_idle();
@ -57,18 +55,5 @@ static const struct platform_suspend_ops imx6q_pm_ops = {
void __init imx6q_pm_init(void)
{
/*
* The l2x0 core code provides an infrastucture to save and restore
* l2x0 registers across suspend/resume cycle. But because imx6q
* retains L2 content during suspend and needs to resume L2 before
* MMU is enabled, it can only utilize register saving support and
* have to take care of restoring on its own. So we save physical
* address of the data structure used by l2x0 core to save registers,
* and later restore the necessary ones in imx6q resume entry.
*/
#ifdef CONFIG_CACHE_L2X0
phys_l2x0_saved_regs = __pa(&l2x0_saved_regs);
#endif
suspend_set_ops(&imx6q_pm_ops);
}