diff options
Diffstat (limited to 'arch/arm/mach-tegra/headsmp.S')
| -rw-r--r-- | arch/arm/mach-tegra/headsmp.S | 61 |
1 files changed, 61 insertions, 0 deletions
diff --git a/arch/arm/mach-tegra/headsmp.S b/arch/arm/mach-tegra/headsmp.S new file mode 100644 index 000000000000..b5349b2f13d2 --- /dev/null +++ b/arch/arm/mach-tegra/headsmp.S @@ -0,0 +1,61 @@ +#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) |