xref: /OK3568_Linux_fs/u-boot/arch/arm/cpu/armv7/start.S (revision 4882a59341e53eb6f0b4789bf948001014eff981)
1/*
2 * armboot - Startup Code for OMAP3530/ARM Cortex CPU-core
3 *
4 * Copyright (c) 2004	Texas Instruments <r-woodruff2@ti.com>
5 *
6 * Copyright (c) 2001	Marius Gröger <mag@sysgo.de>
7 * Copyright (c) 2002	Alex Züpke <azu@sysgo.de>
8 * Copyright (c) 2002	Gary Jennejohn <garyj@denx.de>
9 * Copyright (c) 2003	Richard Woodruff <r-woodruff2@ti.com>
10 * Copyright (c) 2003	Kshitij <kshitij@ti.com>
11 * Copyright (c) 2006-2008 Syed Mohammed Khasim <x0khasim@ti.com>
12 *
13 * SPDX-License-Identifier:	GPL-2.0+
14 */
15
16#include <asm-offsets.h>
17#include <config.h>
18#include <asm/system.h>
19#include <linux/linkage.h>
20#include <asm/armv7.h>
21
22/*************************************************************************
23 *
24 * Startup Code (reset vector)
25 *
26 * Do important init only if we don't start from memory!
27 * Setup memory and board specific bits prior to relocation.
28 * Relocate armboot to ram. Setup stack.
29 *
30 *************************************************************************/
31
32	.globl	reset
33	.globl	save_boot_params_ret
34	.type   save_boot_params_ret,%function
35#ifdef CONFIG_ARMV7_LPAE
36	.global	switch_to_hypervisor_ret
37#endif
38
39#if !CONFIG_IS_ENABLED(TINY_FRAMEWORK)
40
41reset:
42	/* Allow the board to save important registers */
43	b	save_boot_params
44save_boot_params_ret:
45#ifdef CONFIG_ARMV7_LPAE
46/*
47 * check for Hypervisor support
48 */
49	mrc	p15, 0, r0, c0, c1, 1		@ read ID_PFR1
50	and	r0, r0, #CPUID_ARM_VIRT_MASK	@ mask virtualization bits
51	cmp	r0, #(1 << CPUID_ARM_VIRT_SHIFT)
52	beq	switch_to_hypervisor
53switch_to_hypervisor_ret:
54#endif
55	/*
56	 * disable interrupts (FIQ and IRQ), also set the cpu to SVC32 mode,
57	 * except if in HYP mode already
58	 */
59	mrs	r0, cpsr
60	and	r1, r0, #0x1f		@ mask mode bits
61	teq	r1, #0x1a		@ test for HYP mode
62	bicne	r0, r0, #0x1f		@ clear all mode bits
63	orrne	r0, r0, #0x13		@ set SVC mode
64	orr	r0, r0, #0xc0		@ disable FIQ and IRQ
65	msr	cpsr,r0
66
67	/* Enable ACTLR.SMP bit */
68	mrc	p15, 0, r0, c1, c0, 1
69	orr	r0, r0, #(1 << 6)	@ Enable ACTLR.SMP bit
70	mcr	p15, 0, r0, c1, c0, 1
71
72/*
73 * Setup vector:
74 * (OMAP4 spl TEXT_BASE is not 32 byte aligned.
75 * Continue to use ROM code vector only in OMAP4 spl)
76 */
77#if !(defined(CONFIG_OMAP44XX) && defined(CONFIG_SPL_BUILD))
78	/* Set V=0 in CP15 SCTLR register - for VBAR to point to vector */
79	mrc	p15, 0, r0, c1, c0, 0	@ Read CP15 SCTLR Register
80	bic	r0, #CR_V		@ V = 0
81	mcr	p15, 0, r0, c1, c0, 0	@ Write CP15 SCTLR Register
82
83	/* Set vector address in CP15 VBAR register */
84	ldr	r0, =_start
85	mcr	p15, 0, r0, c12, c0, 0	@Set VBAR
86#endif
87
88	/* Enable Asynchronous external abort after vectors setup */
89	mrs	r0, cpsr
90	bic	r0, r0, #0x100		@ CPSR.A bit
91	msr	cpsr_x,r0
92
93	/* the mask ROM code should have PLL and others stable */
94#ifndef CONFIG_SKIP_LOWLEVEL_INIT
95	bl	cpu_init_cp15
96#ifndef CONFIG_SKIP_LOWLEVEL_INIT_ONLY
97	bl	cpu_init_crit
98#endif
99#endif
100
101	bl	_main
102
103/*------------------------------------------------------------------------------*/
104
105ENTRY(c_runtime_cpu_setup)
106/*
107 * If I-cache is enabled invalidate it
108 */
109#ifndef CONFIG_SYS_ICACHE_OFF
110	mcr	p15, 0, r0, c7, c5, 0	@ invalidate icache
111	mcr     p15, 0, r0, c7, c10, 4	@ DSB
112	mcr     p15, 0, r0, c7, c5, 4	@ ISB
113#endif
114
115	bx	lr
116
117ENDPROC(c_runtime_cpu_setup)
118
119#endif/* !CONFIG_IS_ENABLED(TINY_FRAMEWORK) */
120
121/*************************************************************************
122 *
123 * void save_boot_params(u32 r0, u32 r1, u32 r2, u32 r3)
124 *	__attribute__((weak));
125 *
126 * Stack pointer is not yet initialized at this moment
127 * Don't save anything to stack even if compiled with -O0
128 *
129 *************************************************************************/
130ENTRY(save_boot_params)
131	b	save_boot_params_ret		@ back to my caller
132ENDPROC(save_boot_params)
133	.weak	save_boot_params
134
135#ifdef CONFIG_ARMV7_LPAE
136ENTRY(switch_to_hypervisor)
137	b	switch_to_hypervisor_ret
138ENDPROC(switch_to_hypervisor)
139	.weak	switch_to_hypervisor
140#endif
141
142/*************************************************************************
143 *
144 * cpu_init_cp15
145 *
146 * Setup CP15 registers (cache, MMU, TLBs). The I-cache is turned on unless
147 * CONFIG_SYS_ICACHE_OFF is defined.
148 *
149 *************************************************************************/
150ENTRY(cpu_init_cp15)
151	/*
152	 * Invalidate L1 I/D
153	 */
154	mov	r0, #0			@ set up for MCR
155	mcr	p15, 0, r0, c8, c7, 0	@ invalidate TLBs
156	mcr	p15, 0, r0, c7, c5, 0	@ invalidate icache
157	mcr	p15, 0, r0, c7, c5, 6	@ invalidate BP array
158	mcr     p15, 0, r0, c7, c10, 4	@ DSB
159	mcr     p15, 0, r0, c7, c5, 4	@ ISB
160
161	/*
162	 * disable MMU stuff and caches
163	 */
164	mrc	p15, 0, r0, c1, c0, 0
165	bic	r0, r0, #0x00002000	@ clear bits 13 (--V-)
166	bic	r0, r0, #0x00000007	@ clear bits 2:0 (-CAM)
167#if 0 /* There is unalign access when decompress firmware. */
168	orr	r0, r0, #0x00000002	@ set bit 1 (--A-) Align
169#endif
170	orr	r0, r0, #0x00000800	@ set bit 11 (Z---) BTB
171#ifdef CONFIG_SYS_ICACHE_OFF
172	bic	r0, r0, #0x00001000	@ clear bit 12 (I) I-cache
173#else
174	orr	r0, r0, #0x00001000	@ set bit 12 (I) I-cache
175#endif
176	mcr	p15, 0, r0, c1, c0, 0
177
178#ifdef CONFIG_ARM_ERRATA_716044
179	mrc	p15, 0, r0, c1, c0, 0	@ read system control register
180	orr	r0, r0, #1 << 11	@ set bit #11
181	mcr	p15, 0, r0, c1, c0, 0	@ write system control register
182#endif
183
184#if (defined(CONFIG_ARM_ERRATA_742230) || defined(CONFIG_ARM_ERRATA_794072))
185	mrc	p15, 0, r0, c15, c0, 1	@ read diagnostic register
186	orr	r0, r0, #1 << 4		@ set bit #4
187	mcr	p15, 0, r0, c15, c0, 1	@ write diagnostic register
188#endif
189
190#ifdef CONFIG_ARM_ERRATA_743622
191	mrc	p15, 0, r0, c15, c0, 1	@ read diagnostic register
192	orr	r0, r0, #1 << 6		@ set bit #6
193	mcr	p15, 0, r0, c15, c0, 1	@ write diagnostic register
194#endif
195
196#ifdef CONFIG_ARM_ERRATA_751472
197	mrc	p15, 0, r0, c15, c0, 1	@ read diagnostic register
198	orr	r0, r0, #1 << 11	@ set bit #11
199	mcr	p15, 0, r0, c15, c0, 1	@ write diagnostic register
200#endif
201#ifdef CONFIG_ARM_ERRATA_761320
202	mrc	p15, 0, r0, c15, c0, 1	@ read diagnostic register
203	orr	r0, r0, #1 << 21	@ set bit #21
204	mcr	p15, 0, r0, c15, c0, 1	@ write diagnostic register
205#endif
206
207#ifdef CONFIG_ARM_ERRATA_845369
208	mrc     p15, 0, r0, c15, c0, 1	@ read diagnostic register
209	orr     r0, r0, #1 << 22	@ set bit #22
210	mcr     p15, 0, r0, c15, c0, 1	@ write diagnostic register
211#endif
212
213	mov	r5, lr			@ Store my Caller
214	mrc	p15, 0, r1, c0, c0, 0	@ r1 has Read Main ID Register (MIDR)
215	mov	r3, r1, lsr #20		@ get variant field
216	and	r3, r3, #0xf		@ r3 has CPU variant
217	and	r4, r1, #0xf		@ r4 has CPU revision
218	mov	r2, r3, lsl #4		@ shift variant field for combined value
219	orr	r2, r4, r2		@ r2 has combined CPU variant + revision
220
221#ifdef CONFIG_ARM_ERRATA_798870
222	cmp	r2, #0x30		@ Applies to lower than R3p0
223	bge	skip_errata_798870      @ skip if not affected rev
224	cmp	r2, #0x20		@ Applies to including and above R2p0
225	blt	skip_errata_798870      @ skip if not affected rev
226
227	mrc	p15, 1, r0, c15, c0, 0  @ read l2 aux ctrl reg
228	orr	r0, r0, #1 << 7         @ Enable hazard-detect timeout
229	push	{r1-r5}			@ Save the cpu info registers
230	bl	v7_arch_cp15_set_l2aux_ctrl
231	isb				@ Recommended ISB after l2actlr update
232	pop	{r1-r5}			@ Restore the cpu info - fall through
233skip_errata_798870:
234#endif
235
236#ifdef CONFIG_ARM_ERRATA_801819
237	cmp	r2, #0x24		@ Applies to lt including R2p4
238	bgt	skip_errata_801819      @ skip if not affected rev
239	cmp	r2, #0x20		@ Applies to including and above R2p0
240	blt	skip_errata_801819      @ skip if not affected rev
241	mrc	p15, 0, r0, c0, c0, 6	@ pick up REVIDR reg
242	and	r0, r0, #1 << 3		@ check REVIDR[3]
243	cmp	r0, #1 << 3
244	beq	skip_errata_801819	@ skip erratum if REVIDR[3] is set
245
246	mrc	p15, 0, r0, c1, c0, 1	@ read auxilary control register
247	orr	r0, r0, #3 << 27	@ Disables streaming. All write-allocate
248					@ lines allocate in the L1 or L2 cache.
249	orr	r0, r0, #3 << 25	@ Disables streaming. All write-allocate
250					@ lines allocate in the L1 cache.
251	push	{r1-r5}			@ Save the cpu info registers
252	bl	v7_arch_cp15_set_acr
253	pop	{r1-r5}			@ Restore the cpu info - fall through
254skip_errata_801819:
255#endif
256
257#ifdef CONFIG_ARM_ERRATA_454179
258	cmp	r2, #0x21		@ Only on < r2p1
259	bge	skip_errata_454179
260
261	mrc	p15, 0, r0, c1, c0, 1	@ Read ACR
262	orr	r0, r0, #(0x3 << 6)	@ Set DBSM(BIT7) and IBE(BIT6) bits
263	push	{r1-r5}			@ Save the cpu info registers
264	bl	v7_arch_cp15_set_acr
265	pop	{r1-r5}			@ Restore the cpu info - fall through
266
267skip_errata_454179:
268#endif
269
270#ifdef CONFIG_ARM_ERRATA_430973
271	cmp	r2, #0x21		@ Only on < r2p1
272	bge	skip_errata_430973
273
274	mrc	p15, 0, r0, c1, c0, 1	@ Read ACR
275	orr	r0, r0, #(0x1 << 6)	@ Set IBE bit
276	push	{r1-r5}			@ Save the cpu info registers
277	bl	v7_arch_cp15_set_acr
278	pop	{r1-r5}			@ Restore the cpu info - fall through
279
280skip_errata_430973:
281#endif
282
283#ifdef CONFIG_ARM_ERRATA_621766
284	cmp	r2, #0x21		@ Only on < r2p1
285	bge	skip_errata_621766
286
287	mrc	p15, 0, r0, c1, c0, 1	@ Read ACR
288	orr	r0, r0, #(0x1 << 5)	@ Set L1NEON bit
289	push	{r1-r5}			@ Save the cpu info registers
290	bl	v7_arch_cp15_set_acr
291	pop	{r1-r5}			@ Restore the cpu info - fall through
292
293skip_errata_621766:
294#endif
295
296#ifdef CONFIG_ARM_ERRATA_725233
297	cmp	r2, #0x21		@ Only on < r2p1 (Cortex A8)
298	bge	skip_errata_725233
299
300	mrc	p15, 1, r0, c9, c0, 2	@ Read L2ACR
301	orr	r0, r0, #(0x1 << 27)	@ L2 PLD data forwarding disable
302	push	{r1-r5}			@ Save the cpu info registers
303	bl	v7_arch_cp15_set_l2aux_ctrl
304	pop	{r1-r5}			@ Restore the cpu info - fall through
305
306skip_errata_725233:
307#endif
308
309#ifdef CONFIG_ARM_ERRATA_852421
310	mrc	p15, 0, r0, c15, c0, 1	@ read diagnostic register
311	orr	r0, r0, #1 << 24	@ set bit #24
312	mcr	p15, 0, r0, c15, c0, 1	@ write diagnostic register
313#endif
314
315#ifdef CONFIG_ARM_ERRATA_852423
316	mrc	p15, 0, r0, c15, c0, 1	@ read diagnostic register
317	orr	r0, r0, #1 << 12	@ set bit #12
318	mcr	p15, 0, r0, c15, c0, 1	@ write diagnostic register
319#endif
320
321#if defined(CONFIG_ARM_ZERO_CNTVOFF) && defined(CONFIG_SPL_BUILD)
322	/*
323	 * CNTVOFF usage constraints:
324	 * Only accessible from Hyp mode, or from Monitor mode when SCR.NS is
325	 * set to 1.
326	 */
327	/* switch to MON */
328	cps #22
329	isb
330
331	/* Update SCR.NS to non Secure mode */
332	mrc	p15, 0, r0, c1, c1, 0
333	orr r0, r0, #(1 << 0)
334	mcr	p15, 0, r0, c1, c1, 0
335	isb
336
337	/* set vtimer virtual offset 0 */
338	mov	r0, #0
339	mcrr	p15, 4, r0, r0, c14	@ CNTVOFF
340
341	/* Update SCR.NS to Secure mode */
342	mrc	p15, 0, r0, c1, c1, 0
343	bic r0, r0, #(1 << 0)
344	mcr	p15, 0, r0, c1, c1, 0
345	isb
346
347	/* switch back to SVC */
348	cps #19
349	isb
350#endif
351
352	mov	pc, r5			@ back to my caller
353ENDPROC(cpu_init_cp15)
354
355#if !defined(CONFIG_SKIP_LOWLEVEL_INIT) && \
356	!defined(CONFIG_SKIP_LOWLEVEL_INIT_ONLY)
357/*************************************************************************
358 *
359 * CPU_init_critical registers
360 *
361 * setup important registers
362 * setup memory timing
363 *
364 *************************************************************************/
365ENTRY(cpu_init_crit)
366	/*
367	 * Jump to board specific initialization...
368	 * The Mask ROM will have already initialized
369	 * basic memory. Go here to bump up clock rate and handle
370	 * wake up conditions.
371	 */
372	b	lowlevel_init		@ go setup pll,mux,memory
373ENDPROC(cpu_init_crit)
374#endif
375