https://github.com/torvalds/linux
Tip revision: d9875690d9b89a866022ff49e3fcea892345ad92 authored by Linus Torvalds on 16 August 2012, 21:51:24 UTC
Linux 3.6-rc2
Linux 3.6-rc2
Tip revision: d987569
headsmp.S
#include <linux/linkage.h>
#include <linux/init.h>
#include <asm/cache.h>
#include <mach/iomap.h>
#include "flowctrl.h"
#include "reset.h"
#define APB_MISC_GP_HIDREV 0x804
#define PMC_SCRATCH41 0x140
#define RESET_DATA(x) ((TEGRA_RESET_##x)*4)
.macro mov32, reg, val
movw \reg, #:lower16:\val
movt \reg, #:upper16:\val
.endm
.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)
bl v7_invalidate_l1
/* Enable coresight */
mov32 r0, 0xC5ACCE55
mcr p14, 0, r0, c7, c12, 6
b secondary_startup
ENDPROC(tegra_secondary_startup)
.align L1_CACHE_SHIFT
ENTRY(__tegra_cpu_reset_handler_start)
/*
* __tegra_cpu_reset_handler:
*
* Common handler for all CPU reset events.
*
* Register usage within the reset handler:
*
* R7 = CPU present (to the OS) mask
* R8 = CPU in LP1 state mask
* R9 = CPU in LP2 state mask
* R10 = CPU number
* R11 = CPU mask
* R12 = pointer to reset handler data
*
* NOTE: This code is copied to IRAM. All code and data accesses
* must be position-independent.
*/
.align L1_CACHE_SHIFT
ENTRY(__tegra_cpu_reset_handler)
cpsid aif, 0x13 @ SVC mode, interrupts disabled
mrc p15, 0, r10, c0, c0, 5 @ MPIDR
and r10, r10, #0x3 @ R10 = CPU number
mov r11, #1
mov r11, r11, lsl r10 @ R11 = CPU mask
adr r12, __tegra_cpu_reset_handler_data
#ifdef CONFIG_SMP
/* Does the OS know about this CPU? */
ldr r7, [r12, #RESET_DATA(MASK_PRESENT)]
tst r7, r11 @ if !present
bleq __die @ CPU not present (to OS)
#endif
#ifdef CONFIG_ARCH_TEGRA_2x_SOC
/* Are we on Tegra20? */
mov32 r6, TEGRA_APB_MISC_BASE
ldr r0, [r6, #APB_MISC_GP_HIDREV]
and r0, r0, #0xff00
cmp r0, #(0x20 << 8)
bne 1f
/* If not CPU0, don't let CPU0 reset CPU1 now that CPU1 is coming up. */
mov32 r6, TEGRA_PMC_BASE
mov r0, #0
cmp r10, #0
strne r0, [r6, #PMC_SCRATCH41]
1:
#endif
#ifdef CONFIG_SMP
/*
* Can only be secondary boot (initial or hotplug) but CPU 0
* cannot be here.
*/
cmp r10, #0
bleq __die @ CPU0 cannot be here
ldr lr, [r12, #RESET_DATA(STARTUP_SECONDARY)]
cmp lr, #0
bleq __die @ no secondary startup handler
bx lr
#endif
/*
* We don't know why the CPU reset. Just kill it.
* The LR register will contain the address we died at + 4.
*/
__die:
sub lr, lr, #4
mov32 r7, TEGRA_PMC_BASE
str lr, [r7, #PMC_SCRATCH41]
mov32 r7, TEGRA_CLK_RESET_BASE
/* Are we on Tegra20? */
mov32 r6, TEGRA_APB_MISC_BASE
ldr r0, [r6, #APB_MISC_GP_HIDREV]
and r0, r0, #0xff00
cmp r0, #(0x20 << 8)
bne 1f
#ifdef CONFIG_ARCH_TEGRA_2x_SOC
mov32 r0, 0x1111
mov r1, r0, lsl r10
str r1, [r7, #0x340] @ CLK_RST_CPU_CMPLX_SET
#endif
1:
#ifdef CONFIG_ARCH_TEGRA_3x_SOC
mov32 r6, TEGRA_FLOW_CTRL_BASE
cmp r10, #0
moveq r1, #FLOW_CTRL_HALT_CPU0_EVENTS
moveq r2, #FLOW_CTRL_CPU0_CSR
movne r1, r10, lsl #3
addne r2, r1, #(FLOW_CTRL_CPU1_CSR-8)
addne r1, r1, #(FLOW_CTRL_HALT_CPU1_EVENTS-8)
/* Clear CPU "event" and "interrupt" flags and power gate
it when halting but not before it is in the "WFI" state. */
ldr r0, [r6, +r2]
orr r0, r0, #FLOW_CTRL_CSR_INTR_FLAG | FLOW_CTRL_CSR_EVENT_FLAG
orr r0, r0, #FLOW_CTRL_CSR_ENABLE
str r0, [r6, +r2]
/* Unconditionally halt this CPU */
mov r0, #FLOW_CTRL_WAITEVENT
str r0, [r6, +r1]
ldr r0, [r6, +r1] @ memory barrier
dsb
isb
wfi @ CPU should be power gated here
/* If the CPU didn't power gate above just kill it's clock. */
mov r0, r11, lsl #8
str r0, [r7, #348] @ CLK_CPU_CMPLX_SET
#endif
/* If the CPU still isn't dead, just spin here. */
b .
ENDPROC(__tegra_cpu_reset_handler)
.align L1_CACHE_SHIFT
.type __tegra_cpu_reset_handler_data, %object
.globl __tegra_cpu_reset_handler_data
__tegra_cpu_reset_handler_data:
.rept TEGRA_RESET_DATA_SIZE
.long 0
.endr
.align L1_CACHE_SHIFT
ENTRY(__tegra_cpu_reset_handler_end)