diff options
Diffstat (limited to 'arch/arm/mach-tegra/headsmp.S')
| -rw-r--r-- | arch/arm/mach-tegra/headsmp.S | 212 |
1 files changed, 212 insertions, 0 deletions
diff --git a/arch/arm/mach-tegra/headsmp.S b/arch/arm/mach-tegra/headsmp.S new file mode 100644 index 00000000..fef9c2c5 --- /dev/null +++ b/arch/arm/mach-tegra/headsmp.S @@ -0,0 +1,212 @@ +#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) |