linux/arch/arm/mach-tegra/headsmp.S
Joseph Lo 9e32366fe5 ARM: tegra: make device can run on UP
The reset handler code is used for either UP or SMP. To make Tegra device
can compile for UP. It needs to be moved to another file that is not SMP
only. This is because the reset handler also be needed by CPU idle
"powered-down" mode. So we also need to put the reset handler init function
in non-SMP only and init them always.

And currently the implementation of the reset handler to know which CPU is
OK to bring up was identital with "cpu_present_mask". But the
"cpu_present_mask" did not initialize yet when the reset handler init
function was moved to init early function. We use the "cpu_possible_mask"
to replace "cpu_present_mask". Then it can work on both UP and SMP case.

Signed-off-by: Joseph Lo <josephl@nvidia.com>
[swarren: dropped the move of v7_invalidate_l1() from one file to another,
to avoid conflicts with Pavel's cleanup of this function, adjust Makefile
so each line only contains 1 file.]
Signed-off-by: Stephen Warren <swarren@nvidia.com>
2013-01-28 11:14:06 -07:00

58 lines
1.8 KiB
ArmAsm

#include <linux/linkage.h>
#include <linux/init.h>
#include "sleep.h"
.section ".text.head", "ax"
/*
* 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)
bl v7_invalidate_l1
/* Enable coresight */
mov32 r0, 0xC5ACCE55
mcr p14, 0, r0, c7, c12, 6
b secondary_startup
ENDPROC(tegra_secondary_startup)