xref: /openbmc/u-boot/arch/arm/cpu/armv7/start.S (revision 8ee59472)
1/* SPDX-License-Identifier: GPL-2.0+ */
2/*
3 * armboot - Startup Code for OMAP3530/ARM Cortex CPU-core
4 *
5 * Copyright (c) 2004	Texas Instruments <r-woodruff2@ti.com>
6 *
7 * Copyright (c) 2001	Marius Gröger <mag@sysgo.de>
8 * Copyright (c) 2002	Alex Züpke <azu@sysgo.de>
9 * Copyright (c) 2002	Gary Jennejohn <garyj@denx.de>
10 * Copyright (c) 2003	Richard Woodruff <r-woodruff2@ti.com>
11 * Copyright (c) 2003	Kshitij <kshitij@ti.com>
12 * Copyright (c) 2006-2008 Syed Mohammed Khasim <x0khasim@ti.com>
13 */
14
15#include <asm-offsets.h>
16#include <config.h>
17#include <asm/system.h>
18#include <linux/linkage.h>
19#include <asm/armv7.h>
20
21/*************************************************************************
22 *
23 * Startup Code (reset vector)
24 *
25 * Do important init only if we don't start from memory!
26 * Setup memory and board specific bits prior to relocation.
27 * Relocate armboot to ram. Setup stack.
28 *
29 *************************************************************************/
30
31	.globl	reset
32	.globl	save_boot_params_ret
33	.type   save_boot_params_ret,%function
34#ifdef CONFIG_ARMV7_LPAE
35	.global	switch_to_hypervisor_ret
36#endif
37
38reset:
39	/* Allow the board to save important registers */
40	b	save_boot_params
41save_boot_params_ret:
42#ifdef CONFIG_ARMV7_LPAE
43/*
44 * check for Hypervisor support
45 */
46	mrc	p15, 0, r0, c0, c1, 1		@ read ID_PFR1
47	and	r0, r0, #CPUID_ARM_VIRT_MASK	@ mask virtualization bits
48	cmp	r0, #(1 << CPUID_ARM_VIRT_SHIFT)
49	beq	switch_to_hypervisor
50switch_to_hypervisor_ret:
51#endif
52	/*
53	 * disable interrupts (FIQ and IRQ), also set the cpu to SVC32 mode,
54	 * except if in HYP mode already
55	 */
56	mrs	r0, cpsr
57	and	r1, r0, #0x1f		@ mask mode bits
58	teq	r1, #0x1a		@ test for HYP mode
59	bicne	r0, r0, #0x1f		@ clear all mode bits
60	orrne	r0, r0, #0x13		@ set SVC mode
61	orr	r0, r0, #0xc0		@ disable FIQ and IRQ
62	msr	cpsr,r0
63
64/*
65 * Setup vector:
66 * (OMAP4 spl TEXT_BASE is not 32 byte aligned.
67 * Continue to use ROM code vector only in OMAP4 spl)
68 */
69#if !(defined(CONFIG_OMAP44XX) && defined(CONFIG_SPL_BUILD))
70	/* Set V=0 in CP15 SCTLR register - for VBAR to point to vector */
71	mrc	p15, 0, r0, c1, c0, 0	@ Read CP15 SCTLR Register
72	bic	r0, #CR_V		@ V = 0
73	mcr	p15, 0, r0, c1, c0, 0	@ Write CP15 SCTLR Register
74
75#ifdef CONFIG_HAS_VBAR
76	/* Set vector address in CP15 VBAR register */
77	ldr	r0, =_start
78	mcr	p15, 0, r0, c12, c0, 0	@Set VBAR
79#endif
80#endif
81
82	/* the mask ROM code should have PLL and others stable */
83#ifndef CONFIG_SKIP_LOWLEVEL_INIT
84#ifdef CONFIG_CPU_V7A
85	bl	cpu_init_cp15
86#endif
87#ifndef CONFIG_SKIP_LOWLEVEL_INIT_ONLY
88	bl	cpu_init_crit
89#endif
90#endif
91
92	bl	_main
93
94/*------------------------------------------------------------------------------*/
95
96ENTRY(c_runtime_cpu_setup)
97/*
98 * If I-cache is enabled invalidate it
99 */
100#ifndef CONFIG_SYS_ICACHE_OFF
101	mcr	p15, 0, r0, c7, c5, 0	@ invalidate icache
102	mcr     p15, 0, r0, c7, c10, 4	@ DSB
103	mcr     p15, 0, r0, c7, c5, 4	@ ISB
104#endif
105
106	bx	lr
107
108ENDPROC(c_runtime_cpu_setup)
109
110/*************************************************************************
111 *
112 * void save_boot_params(u32 r0, u32 r1, u32 r2, u32 r3)
113 *	__attribute__((weak));
114 *
115 * Stack pointer is not yet initialized at this moment
116 * Don't save anything to stack even if compiled with -O0
117 *
118 *************************************************************************/
119ENTRY(save_boot_params)
120	b	save_boot_params_ret		@ back to my caller
121ENDPROC(save_boot_params)
122	.weak	save_boot_params
123
124#ifdef CONFIG_ARMV7_LPAE
125ENTRY(switch_to_hypervisor)
126	b	switch_to_hypervisor_ret
127ENDPROC(switch_to_hypervisor)
128	.weak	switch_to_hypervisor
129#endif
130
131/*************************************************************************
132 *
133 * cpu_init_cp15
134 *
135 * Setup CP15 registers (cache, MMU, TLBs). The I-cache is turned on unless
136 * CONFIG_SYS_ICACHE_OFF is defined.
137 *
138 *************************************************************************/
139ENTRY(cpu_init_cp15)
140	/*
141	 * Invalidate L1 I/D
142	 */
143	mov	r0, #0			@ set up for MCR
144	mcr	p15, 0, r0, c8, c7, 0	@ invalidate TLBs
145	mcr	p15, 0, r0, c7, c5, 0	@ invalidate icache
146	mcr	p15, 0, r0, c7, c5, 6	@ invalidate BP array
147	mcr     p15, 0, r0, c7, c10, 4	@ DSB
148	mcr     p15, 0, r0, c7, c5, 4	@ ISB
149
150	/*
151	 * disable MMU stuff and caches
152	 */
153	mrc	p15, 0, r0, c1, c0, 0
154	bic	r0, r0, #0x00002000	@ clear bits 13 (--V-)
155	bic	r0, r0, #0x00000007	@ clear bits 2:0 (-CAM)
156	orr	r0, r0, #0x00000002	@ set bit 1 (--A-) Align
157	orr	r0, r0, #0x00000800	@ set bit 11 (Z---) BTB
158#ifdef CONFIG_SYS_ICACHE_OFF
159	bic	r0, r0, #0x00001000	@ clear bit 12 (I) I-cache
160#else
161	orr	r0, r0, #0x00001000	@ set bit 12 (I) I-cache
162#endif
163	mcr	p15, 0, r0, c1, c0, 0
164
165#ifdef CONFIG_ARM_ERRATA_716044
166	mrc	p15, 0, r0, c1, c0, 0	@ read system control register
167	orr	r0, r0, #1 << 11	@ set bit #11
168	mcr	p15, 0, r0, c1, c0, 0	@ write system control register
169#endif
170
171#if (defined(CONFIG_ARM_ERRATA_742230) || defined(CONFIG_ARM_ERRATA_794072))
172	mrc	p15, 0, r0, c15, c0, 1	@ read diagnostic register
173	orr	r0, r0, #1 << 4		@ set bit #4
174	mcr	p15, 0, r0, c15, c0, 1	@ write diagnostic register
175#endif
176
177#ifdef CONFIG_ARM_ERRATA_743622
178	mrc	p15, 0, r0, c15, c0, 1	@ read diagnostic register
179	orr	r0, r0, #1 << 6		@ set bit #6
180	mcr	p15, 0, r0, c15, c0, 1	@ write diagnostic register
181#endif
182
183#ifdef CONFIG_ARM_ERRATA_751472
184	mrc	p15, 0, r0, c15, c0, 1	@ read diagnostic register
185	orr	r0, r0, #1 << 11	@ set bit #11
186	mcr	p15, 0, r0, c15, c0, 1	@ write diagnostic register
187#endif
188#ifdef CONFIG_ARM_ERRATA_761320
189	mrc	p15, 0, r0, c15, c0, 1	@ read diagnostic register
190	orr	r0, r0, #1 << 21	@ set bit #21
191	mcr	p15, 0, r0, c15, c0, 1	@ write diagnostic register
192#endif
193
194#ifdef CONFIG_ARM_ERRATA_845369
195	mrc     p15, 0, r0, c15, c0, 1	@ read diagnostic register
196	orr     r0, r0, #1 << 22	@ set bit #22
197	mcr     p15, 0, r0, c15, c0, 1	@ write diagnostic register
198#endif
199
200	mov	r5, lr			@ Store my Caller
201	mrc	p15, 0, r1, c0, c0, 0	@ r1 has Read Main ID Register (MIDR)
202	mov	r3, r1, lsr #20		@ get variant field
203	and	r3, r3, #0xf		@ r3 has CPU variant
204	and	r4, r1, #0xf		@ r4 has CPU revision
205	mov	r2, r3, lsl #4		@ shift variant field for combined value
206	orr	r2, r4, r2		@ r2 has combined CPU variant + revision
207
208#ifdef CONFIG_ARM_ERRATA_798870
209	cmp	r2, #0x30		@ Applies to lower than R3p0
210	bge	skip_errata_798870      @ skip if not affected rev
211	cmp	r2, #0x20		@ Applies to including and above R2p0
212	blt	skip_errata_798870      @ skip if not affected rev
213
214	mrc	p15, 1, r0, c15, c0, 0  @ read l2 aux ctrl reg
215	orr	r0, r0, #1 << 7         @ Enable hazard-detect timeout
216	push	{r1-r5}			@ Save the cpu info registers
217	bl	v7_arch_cp15_set_l2aux_ctrl
218	isb				@ Recommended ISB after l2actlr update
219	pop	{r1-r5}			@ Restore the cpu info - fall through
220skip_errata_798870:
221#endif
222
223#ifdef CONFIG_ARM_ERRATA_801819
224	cmp	r2, #0x24		@ Applies to lt including R2p4
225	bgt	skip_errata_801819      @ skip if not affected rev
226	cmp	r2, #0x20		@ Applies to including and above R2p0
227	blt	skip_errata_801819      @ skip if not affected rev
228	mrc	p15, 0, r0, c0, c0, 6	@ pick up REVIDR reg
229	and	r0, r0, #1 << 3		@ check REVIDR[3]
230	cmp	r0, #1 << 3
231	beq	skip_errata_801819	@ skip erratum if REVIDR[3] is set
232
233	mrc	p15, 0, r0, c1, c0, 1	@ read auxilary control register
234	orr	r0, r0, #3 << 27	@ Disables streaming. All write-allocate
235					@ lines allocate in the L1 or L2 cache.
236	orr	r0, r0, #3 << 25	@ Disables streaming. All write-allocate
237					@ lines allocate in the L1 cache.
238	push	{r1-r5}			@ Save the cpu info registers
239	bl	v7_arch_cp15_set_acr
240	pop	{r1-r5}			@ Restore the cpu info - fall through
241skip_errata_801819:
242#endif
243
244#ifdef CONFIG_ARM_ERRATA_454179
245	mrc	p15, 0, r0, c1, c0, 1	@ Read ACR
246
247	cmp	r2, #0x21		@ Only on < r2p1
248	orrlt	r0, r0, #(0x3 << 6)	@ Set DBSM(BIT7) and IBE(BIT6) bits
249
250	push	{r1-r5}			@ Save the cpu info registers
251	bl	v7_arch_cp15_set_acr
252	pop	{r1-r5}			@ Restore the cpu info - fall through
253#endif
254
255#ifdef CONFIG_ARM_ERRATA_430973
256	mrc	p15, 0, r0, c1, c0, 1	@ Read ACR
257
258	cmp	r2, #0x21		@ Only on < r2p1
259	orrlt	r0, r0, #(0x1 << 6)	@ Set IBE bit
260
261	push	{r1-r5}			@ Save the cpu info registers
262	bl	v7_arch_cp15_set_acr
263	pop	{r1-r5}			@ Restore the cpu info - fall through
264#endif
265
266#ifdef CONFIG_ARM_ERRATA_621766
267	mrc	p15, 0, r0, c1, c0, 1	@ Read ACR
268
269	cmp	r2, #0x21		@ Only on < r2p1
270	orrlt	r0, r0, #(0x1 << 5)	@ Set L1NEON bit
271
272	push	{r1-r5}			@ Save the cpu info registers
273	bl	v7_arch_cp15_set_acr
274	pop	{r1-r5}			@ Restore the cpu info - fall through
275#endif
276
277#ifdef CONFIG_ARM_ERRATA_725233
278	mrc	p15, 1, r0, c9, c0, 2	@ Read L2ACR
279
280	cmp	r2, #0x21		@ Only on < r2p1 (Cortex A8)
281	orrlt	r0, r0, #(0x1 << 27)	@ L2 PLD data forwarding disable
282
283	push	{r1-r5}			@ Save the cpu info registers
284	bl	v7_arch_cp15_set_l2aux_ctrl
285	pop	{r1-r5}			@ Restore the cpu info - fall through
286#endif
287
288#ifdef CONFIG_ARM_ERRATA_852421
289	mrc	p15, 0, r0, c15, c0, 1	@ read diagnostic register
290	orr	r0, r0, #1 << 24	@ set bit #24
291	mcr	p15, 0, r0, c15, c0, 1	@ write diagnostic register
292#endif
293
294#ifdef CONFIG_ARM_ERRATA_852423
295	mrc	p15, 0, r0, c15, c0, 1	@ read diagnostic register
296	orr	r0, r0, #1 << 12	@ set bit #12
297	mcr	p15, 0, r0, c15, c0, 1	@ write diagnostic register
298#endif
299
300	mov	pc, r5			@ back to my caller
301ENDPROC(cpu_init_cp15)
302
303#if !defined(CONFIG_SKIP_LOWLEVEL_INIT) && \
304	!defined(CONFIG_SKIP_LOWLEVEL_INIT_ONLY)
305/*************************************************************************
306 *
307 * CPU_init_critical registers
308 *
309 * setup important registers
310 * setup memory timing
311 *
312 *************************************************************************/
313ENTRY(cpu_init_crit)
314	/*
315	 * Jump to board specific initialization...
316	 * The Mask ROM will have already initialized
317	 * basic memory. Go here to bump up clock rate and handle
318	 * wake up conditions.
319	 */
320	b	lowlevel_init		@ go setup pll,mux,memory
321ENDPROC(cpu_init_crit)
322#endif
323