diff options
Diffstat (limited to 'arch/arm/mach-tegra/reset-handler.S')
| -rw-r--r-- | arch/arm/mach-tegra/reset-handler.S | 270 | 
1 files changed, 270 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 00000000000..e6de88a2ea0 --- /dev/null +++ b/arch/arm/mach-tegra/reset-handler.S @@ -0,0 +1,270 @@ +/* + * 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 + +	cpu_id	r0 +	cmp	r0, #0				@ CPU0? + THUMB(	it	ne ) +	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: + * + *      Others: scratch + *      R6  = SoC ID << 8 + *      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 + +	mov32	r6, TEGRA_APB_MISC_BASE +	ldr	r6, [r6, #APB_MISC_GP_HIDREV] +	and	r6, r6, #0xff00 +#ifdef CONFIG_ARCH_TEGRA_2x_SOC +t20_check: +	cmp	r6, #(0x20 << 8) +	bne	after_t20_check +t20_errata: +	# Tegra20 is a Cortex-A9 r1p1 +	mrc	p15, 0, r0, c1, c0, 0   @ read system control register +	orr	r0, r0, #1 << 14        @ erratum 716044 +	mcr	p15, 0, r0, c1, c0, 0   @ write system control register +	mrc	p15, 0, r0, c15, c0, 1  @ read diagnostic register +	orr	r0, r0, #1 << 4         @ erratum 742230 +	orr	r0, r0, #1 << 11        @ erratum 751472 +	mcr	p15, 0, r0, c15, c0, 1  @ write diagnostic register +	b	after_errata +after_t20_check: +#endif +#ifdef CONFIG_ARCH_TEGRA_3x_SOC +t30_check: +	cmp	r6, #(0x30 << 8) +	bne	after_t30_check +t30_errata: +	# Tegra30 is a Cortex-A9 r2p9 +	mrc	p15, 0, r0, c15, c0, 1  @ read diagnostic register +	orr	r0, r0, #1 << 6         @ erratum 743622 +	orr	r0, r0, #1 << 11        @ erratum 751472 +	mcr	p15, 0, r0, c15, c0, 1  @ write diagnostic register +	b	after_errata +after_t30_check: +#endif +after_errata: +	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? */ +	cmp	r6, #(0x20 << 8) +	bne	1f +	/* If not CPU0, don't let CPU0 reset CPU1 now that CPU1 is coming up. */ +	mov32	r5, TEGRA_PMC_BASE +	mov	r0, #0 +	cmp	r10, #0 +	strne	r0, [r5, #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)  |