diff options
Diffstat (limited to 'arch/arm/mach-tegra/reset-handler.S')
| -rw-r--r-- | arch/arm/mach-tegra/reset-handler.S | 239 |
1 files changed, 239 insertions, 0 deletions
diff --git a/arch/arm/mach-tegra/reset-handler.S b/arch/arm/mach-tegra/reset-handler.S new file mode 100644 index 000000000000..54382ceade4a --- /dev/null +++ b/arch/arm/mach-tegra/reset-handler.S @@ -0,0 +1,239 @@ +/* + * Copyright (c) 2012, NVIDIA Corporation. All rights reserved. + * + * This program is free software; you can redistribute it and/or modify it + * under the terms and conditions of the GNU General Public License, + * version 2, as published by the Free Software Foundation. + * + * This program is distributed in the hope it will be useful, but WITHOUT + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for + * more details. + * + * You should have received a copy of the GNU General Public License + * along with this program. If not, see <http://www.gnu.org/licenses/>. + */ + +#include <linux/linkage.h> +#include <linux/init.h> + +#include <asm/cache.h> +#include <asm/asm-offsets.h> +#include <asm/hardware/cache-l2x0.h> + +#include "flowctrl.h" +#include "iomap.h" +#include "reset.h" +#include "sleep.h" + +#define APB_MISC_GP_HIDREV 0x804 +#define PMC_SCRATCH41 0x140 + +#define RESET_DATA(x) ((TEGRA_RESET_##x)*4) + +#ifdef CONFIG_PM_SLEEP +/* + * tegra_resume + * + * CPU boot vector when restarting the a CPU following + * an LP2 transition. Also branched to by LP0 and LP1 resume after + * re-enabling sdram. + */ +ENTRY(tegra_resume) + bl v7_invalidate_l1 + /* Enable coresight */ + mov32 r0, 0xC5ACCE55 + mcr p14, 0, r0, c7, c12, 6 + + cpu_id r0 + cmp r0, #0 @ CPU0? + bne cpu_resume @ no + +#ifdef CONFIG_ARCH_TEGRA_3x_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) + beq 1f @ Yes + /* Clear the flow controller flags for this CPU. */ + mov32 r2, TEGRA_FLOW_CTRL_BASE + FLOW_CTRL_CPU0_CSR @ CPU0 CSR + ldr r1, [r2] + /* Clear event & intr flag */ + orr r1, r1, \ + #FLOW_CTRL_CSR_INTR_FLAG | FLOW_CTRL_CSR_EVENT_FLAG + movw r0, #0x0FFD @ enable, cluster_switch, immed, & bitmaps + bic r1, r1, r0 + str r1, [r2] +1: +#endif + +#ifdef CONFIG_HAVE_ARM_SCU + /* enable SCU */ + mov32 r0, TEGRA_ARM_PERIF_BASE + ldr r1, [r0] + orr r1, r1, #1 + str r1, [r0] +#endif + + /* L2 cache resume & re-enable */ + l2_cache_resume r0, r1, r2, l2x0_saved_regs_addr + + b cpu_resume +ENDPROC(tegra_resume) +#endif + +#ifdef CONFIG_CACHE_L2X0 + .globl l2x0_saved_regs_addr +l2x0_saved_regs_addr: + .long 0 +#endif + + .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 + + /* Waking up from LP2? */ + ldr r9, [r12, #RESET_DATA(MASK_LP2)] + tst r9, r11 @ if in_lp2 + beq __is_not_lp2 + ldr lr, [r12, #RESET_DATA(STARTUP_LP2)] + cmp lr, #0 + bleq __die @ no LP2 startup handler + bx lr + +__is_not_lp2: + +#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) |