xref: /linux/arch/arm/mach-tegra/reset-handler.S (revision a4eb44a6435d6d8f9e642407a4a06f65eb90ca04)
1/* SPDX-License-Identifier: GPL-2.0-only */
2/*
3 * Copyright (c) 2012, NVIDIA Corporation. All rights reserved.
4 */
5
6#include <linux/init.h>
7#include <linux/linkage.h>
8
9#include <soc/tegra/flowctrl.h>
10#include <soc/tegra/fuse.h>
11
12#include <asm/assembler.h>
13#include <asm/asm-offsets.h>
14#include <asm/cache.h>
15
16#include "iomap.h"
17#include "reset.h"
18#include "sleep.h"
19
20#define PMC_SCRATCH41	0x140
21
22#ifdef CONFIG_PM_SLEEP
23/*
24 *	tegra_resume
25 *
26 *	  CPU boot vector when restarting the a CPU following
27 *	  an LP2 transition. Also branched to by LP0 and LP1 resume after
28 *	  re-enabling sdram.
29 *
30 *	r6: SoC ID
31 *	r8: CPU part number
32 */
33ENTRY(tegra_resume)
34	check_cpu_part_num 0xc09, r8, r9
35	bleq	v7_invalidate_l1
36
37	cpu_id	r0
38	cmp	r0, #0				@ CPU0?
39 THUMB(	it	ne )
40	bne	cpu_resume			@ no
41
42	tegra_get_soc_id TEGRA_APB_MISC_BASE, r6
43	/* Are we on Tegra20? */
44	cmp	r6, #TEGRA20
45	beq	1f				@ Yes
46	/* Clear the flow controller flags for this CPU. */
47	cpu_to_csr_reg r3, r0
48	mov32	r2, TEGRA_FLOW_CTRL_BASE
49	ldr	r1, [r2, r3]
50	/* Clear event & intr flag */
51	orr	r1, r1, \
52		#FLOW_CTRL_CSR_INTR_FLAG | FLOW_CTRL_CSR_EVENT_FLAG
53	movw	r0, #0x3FFD	@ enable, cluster_switch, immed, bitmaps
54				@ & ext flags for CPU power mgnt
55	bic	r1, r1, r0
56	str	r1, [r2, r3]
571:
58
59	mov32	r9, 0xc09
60	cmp	r8, r9
61	bne	end_ca9_scu_l2_resume
62#ifdef CONFIG_HAVE_ARM_SCU
63	/* enable SCU */
64	mov32	r0, TEGRA_ARM_PERIF_BASE
65	ldr	r1, [r0]
66	orr	r1, r1, #1
67	str	r1, [r0]
68#endif
69	bl	tegra_resume_trusted_foundations
70
71#ifdef CONFIG_CACHE_L2X0
72	/* L2 cache resume & re-enable */
73	bl	l2c310_early_resume
74#endif
75end_ca9_scu_l2_resume:
76	mov32	r9, 0xc0f
77	cmp	r8, r9
78	bleq	tegra_init_l2_for_a15
79
80	b	cpu_resume
81ENDPROC(tegra_resume)
82
83/*
84 *	tegra_resume_trusted_foundations
85 *
86 *	  Trusted Foundations firmware initialization.
87 *
88 *	Doesn't return if firmware presents.
89 *	Corrupted registers: r1, r2
90 */
91ENTRY(tegra_resume_trusted_foundations)
92	/* Check whether Trusted Foundations firmware presents. */
93	mov32	r2, TEGRA_IRAM_BASE + TEGRA_IRAM_RESET_HANDLER_OFFSET
94	ldr	r1, =__tegra_cpu_reset_handler_data_offset + \
95							RESET_DATA(TF_PRESENT)
96	ldr	r1, [r2, r1]
97	cmp	r1, #0
98	reteq	lr
99
100 .arch_extension sec
101	/*
102	 * First call after suspend wakes firmware. No arguments required
103	 * for some firmware versions. Downstream kernel of ASUS TF300T uses
104	 * r0=3 for the wake-up notification.
105	 */
106	mov	r0, #3
107	smc	#0
108
109	b	cpu_resume
110ENDPROC(tegra_resume_trusted_foundations)
111#endif
112
113	.align L1_CACHE_SHIFT
114ENTRY(__tegra_cpu_reset_handler_start)
115
116/*
117 * __tegra_cpu_reset_handler:
118 *
119 * Common handler for all CPU reset events.
120 *
121 * Register usage within the reset handler:
122 *
123 *      Others: scratch
124 *      R6  = SoC ID
125 *      R7  = CPU present (to the OS) mask
126 *      R8  = CPU in LP1 state mask
127 *      R9  = CPU in LP2 state mask
128 *      R10 = CPU number
129 *      R11 = CPU mask
130 *      R12 = pointer to reset handler data
131 *
132 * NOTE: This code is copied to IRAM. All code and data accesses
133 *       must be position-independent.
134 */
135
136	.arm
137	.align L1_CACHE_SHIFT
138ENTRY(__tegra_cpu_reset_handler)
139
140	cpsid	aif, 0x13			@ SVC mode, interrupts disabled
141
142	tegra_get_soc_id TEGRA_APB_MISC_BASE, r6
143
144	adr	r12, __tegra_cpu_reset_handler_data
145	ldr	r5, [r12, #RESET_DATA(TF_PRESENT)]
146	cmp	r5, #0
147	bne	after_errata
148
149#ifdef CONFIG_ARCH_TEGRA_2x_SOC
150t20_check:
151	cmp	r6, #TEGRA20
152	bne	after_t20_check
153t20_errata:
154	# Tegra20 is a Cortex-A9 r1p1
155	mrc	p15, 0, r0, c1, c0, 0   @ read system control register
156	orr	r0, r0, #1 << 14        @ erratum 716044
157	mcr	p15, 0, r0, c1, c0, 0   @ write system control register
158	mrc	p15, 0, r0, c15, c0, 1  @ read diagnostic register
159	orr	r0, r0, #1 << 4         @ erratum 742230
160	orr	r0, r0, #1 << 11        @ erratum 751472
161	mcr	p15, 0, r0, c15, c0, 1  @ write diagnostic register
162	b	after_errata
163after_t20_check:
164#endif
165#ifdef CONFIG_ARCH_TEGRA_3x_SOC
166t30_check:
167	cmp	r6, #TEGRA30
168	bne	after_t30_check
169t30_errata:
170	# Tegra30 is a Cortex-A9 r2p9
171	mrc	p15, 0, r0, c15, c0, 1  @ read diagnostic register
172	orr	r0, r0, #1 << 6         @ erratum 743622
173	orr	r0, r0, #1 << 11        @ erratum 751472
174	mcr	p15, 0, r0, c15, c0, 1  @ write diagnostic register
175	b	after_errata
176after_t30_check:
177#endif
178after_errata:
179	mrc	p15, 0, r10, c0, c0, 5		@ MPIDR
180	and	r10, r10, #0x3			@ R10 = CPU number
181	mov	r11, #1
182	mov	r11, r11, lsl r10  		@ R11 = CPU mask
183
184#ifdef CONFIG_SMP
185	/* Does the OS know about this CPU? */
186	ldr	r7, [r12, #RESET_DATA(MASK_PRESENT)]
187	tst	r7, r11 			@ if !present
188	bleq	__die				@ CPU not present (to OS)
189#endif
190
191	/* Waking up from LP1? */
192	ldr	r8, [r12, #RESET_DATA(MASK_LP1)]
193	tst	r8, r11				@ if in_lp1
194	beq	__is_not_lp1
195	cmp	r10, #0
196	bne	__die				@ only CPU0 can be here
197	ldr	lr, [r12, #RESET_DATA(STARTUP_LP1)]
198	cmp	lr, #0
199	bleq	__die				@ no LP1 startup handler
200 THUMB(	add	lr, lr, #1 )			@ switch to Thumb mode
201	bx	lr
202__is_not_lp1:
203
204	/* Waking up from LP2? */
205	ldr	r9, [r12, #RESET_DATA(MASK_LP2)]
206	tst	r9, r11				@ if in_lp2
207	beq	__is_not_lp2
208	ldr	lr, [r12, #RESET_DATA(STARTUP_LP2)]
209	cmp	lr, #0
210	bleq	__die				@ no LP2 startup handler
211	bx	lr
212
213__is_not_lp2:
214
215#ifdef CONFIG_SMP
216	/*
217	 * Can only be secondary boot (initial or hotplug)
218	 * CPU0 can't be here for Tegra20/30
219	 */
220	cmp	r6, #TEGRA114
221	beq	__no_cpu0_chk
222	cmp	r10, #0
223	bleq	__die				@ CPU0 cannot be here
224__no_cpu0_chk:
225	ldr	lr, [r12, #RESET_DATA(STARTUP_SECONDARY)]
226	cmp	lr, #0
227	bleq	__die				@ no secondary startup handler
228	bx	lr
229#endif
230
231/*
232 * We don't know why the CPU reset. Just kill it.
233 * The LR register will contain the address we died at + 4.
234 */
235
236__die:
237	sub	lr, lr, #4
238	mov32	r7, TEGRA_PMC_BASE
239	str	lr, [r7, #PMC_SCRATCH41]
240
241	mov32	r7, TEGRA_CLK_RESET_BASE
242
243	/* Are we on Tegra20? */
244	cmp	r6, #TEGRA20
245	bne	1f
246
247#ifdef CONFIG_ARCH_TEGRA_2x_SOC
248	mov32	r0, 0x1111
249	mov	r1, r0, lsl r10
250	str	r1, [r7, #0x340]		@ CLK_RST_CPU_CMPLX_SET
251#endif
2521:
253#ifdef CONFIG_ARCH_TEGRA_3x_SOC
254	mov32	r6, TEGRA_FLOW_CTRL_BASE
255
256	cmp	r10, #0
257	moveq	r1, #FLOW_CTRL_HALT_CPU0_EVENTS
258	moveq	r2, #FLOW_CTRL_CPU0_CSR
259	movne	r1, r10, lsl #3
260	addne	r2, r1, #(FLOW_CTRL_CPU1_CSR-8)
261	addne	r1, r1, #(FLOW_CTRL_HALT_CPU1_EVENTS-8)
262
263	/* Clear CPU "event" and "interrupt" flags and power gate
264	   it when halting but not before it is in the "WFI" state. */
265	ldr	r0, [r6, +r2]
266	orr	r0, r0, #FLOW_CTRL_CSR_INTR_FLAG | FLOW_CTRL_CSR_EVENT_FLAG
267	orr	r0, r0, #FLOW_CTRL_CSR_ENABLE
268	str	r0, [r6, +r2]
269
270	/* Unconditionally halt this CPU */
271	mov	r0, #FLOW_CTRL_WAITEVENT
272	str	r0, [r6, +r1]
273	ldr	r0, [r6, +r1]			@ memory barrier
274
275	dsb
276	isb
277	wfi					@ CPU should be power gated here
278
279	/* If the CPU didn't power gate above just kill it's clock. */
280
281	mov	r0, r11, lsl #8
282	str	r0, [r7, #348]			@ CLK_CPU_CMPLX_SET
283#endif
284
285	/* If the CPU still isn't dead, just spin here. */
286	b	.
287ENDPROC(__tegra_cpu_reset_handler)
288
289	.align L1_CACHE_SHIFT
290	.type	__tegra_cpu_reset_handler_data, %object
291	.globl	__tegra_cpu_reset_handler_data
292	.globl	__tegra_cpu_reset_handler_data_offset
293	.equ	__tegra_cpu_reset_handler_data_offset, \
294					. - __tegra_cpu_reset_handler_start
295__tegra_cpu_reset_handler_data:
296	.rept   TEGRA_RESET_DATA_SIZE
297	.long   0
298	.endr
299	.align L1_CACHE_SHIFT
300
301ENTRY(__tegra_cpu_reset_handler_end)
302