linux/arch/arm/mach-imx/head-v7.S

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/*
* Copyright 2011 Freescale Semiconductor, Inc.
* Copyright 2011 Linaro Ltd.
*
* The code contained herein is licensed under the GNU General Public
* License. You may obtain a copy of the GNU General Public License
* Version 2 or later at the following locations:
*
* http://www.opensource.org/licenses/gpl-license.html
* http://www.gnu.org/copyleft/gpl.html
*/
#include <linux/linkage.h>
#include <linux/init.h>
#include <asm/asm-offsets.h>
#include <asm/hardware/cache-l2x0.h>
.section ".text.head", "ax"
__CPUINIT
/*
* The secondary kernel init calls v7_flush_dcache_all before it enables
* the L1; however, the L1 comes out of reset in an undefined state, so
* the clean + invalidate performed by v7_flush_dcache_all causes a bunch
* of cache lines with uninitialized data and uninitialized tags to get
* written out to memory, which does really unpleasant things to the main
* processor. We fix this by performing an invalidate, rather than a
* clean + invalidate, before jumping into the kernel.
*
* This funciton is cloned from arch/arm/mach-tegra/headsmp.S, and needs
* to be called for both secondary cores startup and primary core resume
* procedures. Ideally, it should be moved into arch/arm/mm/cache-v7.S.
*/
ENTRY(v7_invalidate_l1)
mov r0, #0
mcr p15, 2, r0, c0, c0, 0
mrc p15, 1, r0, c0, c0, 0
ldr r1, =0x7fff
and r2, r1, r0, lsr #13
ldr r1, =0x3ff
and r3, r1, r0, lsr #3 @ NumWays - 1
add r2, r2, #1 @ NumSets
and r0, r0, #0x7
add r0, r0, #4 @ SetShift
clz r1, r3 @ WayShift
add r4, r3, #1 @ NumWays
1: sub r2, r2, #1 @ NumSets--
mov r3, r4 @ Temp = NumWays
2: subs r3, r3, #1 @ Temp--
mov r5, r3, lsl r1
mov r6, r2, lsl r0
orr r5, r5, r6 @ Reg = (Temp<<WayShift)|(NumSets<<SetShift)
mcr p15, 0, r5, c7, c6, 2
bgt 2b
cmp r2, #0
bgt 1b
dsb
isb
mov pc, lr
ENDPROC(v7_invalidate_l1)
#ifdef CONFIG_SMP
ENTRY(v7_secondary_startup)
bl v7_invalidate_l1
b secondary_startup
ENDPROC(v7_secondary_startup)
#endif
/*
* 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.
*/
.data
.align
.macro pl310_resume
ldr r2, phys_l2x0_saved_regs
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
mov r1, #0x1
str r1, [r0, #L2X0_CTRL] @ re-enable L2
.endm
ENTRY(v7_cpu_resume)
bl v7_invalidate_l1
pl310_resume
b cpu_resume
ENDPROC(v7_cpu_resume)
.globl phys_l2x0_saved_regs
phys_l2x0_saved_regs:
.long 0