linux-vybrid_public/arch/arm/mach-tegra/headsmp.S

#include <linux/linkage.h>
#include <linux/init.h>

        .section ".text.head", "ax"
	__CPUINIT

/*
 * Tegra specific entry point for secondary CPUs.
 *   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.
 */
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)

ENTRY(tegra_secondary_startup)
	msr	cpsr_fsxc, #0xd3
        bl      v7_invalidate_l1
	mrc	p15, 0, r0, c0, c0, 5
        and	r0, r0, #15
        ldr     r1, =0x6000f100
        str     r0, [r1]
1:      ldr     r2, [r1]
        cmp     r0, r2
        beq     1b
        b       secondary_startup
ENDPROC(tegra_secondary_startup)