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1/*
2 * Copyright (c) 2015-2017, ARM Limited and Contributors. All rights reserved.
3 *
4 * SPDX-License-Identifier: BSD-3-Clause
5 */
6
7#ifndef __EL3_COMMON_MACROS_S__
8#define __EL3_COMMON_MACROS_S__
9
10#include <arch.h>
11#include <asm_macros.S>
12
13	/*
14	 * Helper macro to initialise EL3 registers we care about.
15	 */
16	.macro el3_arch_init_common _exception_vectors
17	/* ---------------------------------------------------------------------
18	 * SCTLR_EL3 has already been initialised - read current value before
19	 * modifying.
20	 *
21	 * SCTLR_EL3.I: Enable the instruction cache.
22	 *
23	 * SCTLR_EL3.SA: Enable Stack Aligment check. A SP alignment fault
24	 *  exception is generated if a load or store instruction executed at
25	 *  EL3 uses the SP as the base address and the SP is not aligned to a
26	 *  16-byte boundary.
27	 *
28	 * SCTLR_EL3.A: Enable Alignment fault checking. All instructions that
29	 *  load or store one or more registers have an alignment check that the
30	 *  address being accessed is aligned to the size of the data element(s)
31	 *  being accessed.
32	 * ---------------------------------------------------------------------
33	 */
34	mov	x1, #(SCTLR_I_BIT | SCTLR_A_BIT | SCTLR_SA_BIT)
35	mrs	x0, sctlr_el3
36	orr	x0, x0, x1
37	msr	sctlr_el3, x0
38	isb
39
40#ifdef IMAGE_BL31
41	/* ---------------------------------------------------------------------
42	 * Initialise the per-cpu cache pointer to the CPU.
43	 * This is done early to enable crash reporting to have access to crash
44	 * stack. Since crash reporting depends on cpu_data to report the
45	 * unhandled exception, not doing so can lead to recursive exceptions
46	 * due to a NULL TPIDR_EL3.
47	 * ---------------------------------------------------------------------
48	 */
49	bl	init_cpu_data_ptr
50#endif /* IMAGE_BL31 */
51
52	/* ---------------------------------------------------------------------
53	 * Set the exception vectors.
54	 * ---------------------------------------------------------------------
55	 */
56	adr	x0, \_exception_vectors
57	msr	vbar_el3, x0
58	isb
59
60	/* ---------------------------------------------------------------------
61	 * Initialise SCR_EL3, setting all fields rather than relying on hw.
62	 * All fields are architecturally UNKNOWN on reset. The following fields
63	 * do not change during the TF lifetime. The remaining fields are set to
64	 * zero here but are updated ahead of transitioning to a lower EL in the
65	 * function cm_init_context_common().
66	 *
67	 * SCR_EL3.TWE: Set to zero so that execution of WFE instructions at
68	 *  EL2, EL1 and EL0 are not trapped to EL3.
69	 *
70	 * SCR_EL3.TWI: Set to zero so that execution of WFI instructions at
71	 *  EL2, EL1 and EL0 are not trapped to EL3.
72	 *
73	 * SCR_EL3.SIF: Set to one to disable instruction fetches from
74	 *  Non-secure memory.
75	 *
76	 * SCR_EL3.SMD: Set to zero to enable SMC calls at EL1 and above, from
77	 *  both Security states and both Execution states.
78	 *
79	 * SCR_EL3.EA: Set to one to route External Aborts and SError Interrupts
80	 *  to EL3 when executing at any EL.
81	 * ---------------------------------------------------------------------
82	 */
83	mov	x0, #((SCR_RESET_VAL | SCR_EA_BIT | SCR_SIF_BIT) \
84			& ~(SCR_TWE_BIT | SCR_TWI_BIT | SCR_SMD_BIT))
85	msr	scr_el3, x0
86
87	/* ---------------------------------------------------------------------
88	 * Initialise MDCR_EL3, setting all fields rather than relying on hw.
89	 * Some fields are architecturally UNKNOWN on reset.
90	 *
91	 * MDCR_EL3.SDD: Set to one to disable AArch64 Secure self-hosted debug.
92	 *  Debug exceptions, other than Breakpoint Instruction exceptions, are
93	 *  disabled from all ELs in Secure state.
94	 *
95	 * MDCR_EL3.SPD32: Set to 0b10 to disable AArch32 Secure self-hosted
96	 *  privileged debug from S-EL1.
97	 *
98	 * MDCR_EL3.NSPB (ARM v8.2): SPE enabled in non-secure state and
99	 * disabled in secure state. Accesses to SPE registers at SEL1 generate
100	 * trap exceptions to EL3.
101	 *
102	 * MDCR_EL3.TDOSA: Set to zero so that EL2 and EL2 System register
103	 *  access to the powerdown debug registers do not trap to EL3.
104	 *
105	 * MDCR_EL3.TDA: Set to zero to allow EL0, EL1 and EL2 access to the
106	 *  debug registers, other than those registers that are controlled by
107	 *  MDCR_EL3.TDOSA.
108	 *
109	 * MDCR_EL3.TPM: Set to zero so that EL0, EL1, and EL2 System register
110	 *  accesses to all Performance Monitors registers do not trap to EL3.
111	 * ---------------------------------------------------------------------
112	 */
113	mov_imm	x0, ((MDCR_EL3_RESET_VAL | MDCR_SDD_BIT | MDCR_SPD32(MDCR_SPD32_DISABLE)) \
114			& ~(MDCR_TDOSA_BIT | MDCR_TDA_BIT | MDCR_TPM_BIT))
115
116#if ENABLE_SPE_FOR_LOWER_ELS
117	/* Detect if SPE is implemented */
118	mrs	x1, id_aa64dfr0_el1
119	ubfx	x1, x1, #ID_AA64DFR0_PMS_SHIFT, #ID_AA64DFR0_PMS_LENGTH
120	cmp	x1, #0x1
121	b.ne	1f
122
123	/* Enable SPE for use by normal world */
124	orr	x0, x0, #MDCR_NSPB(MDCR_NSPB_EL1)
1251:
126#endif
127
128	msr	mdcr_el3, x0
129
130	/* ---------------------------------------------------------------------
131	 * Enable External Aborts and SError Interrupts now that the exception
132	 * vectors have been setup.
133	 * ---------------------------------------------------------------------
134	 */
135	msr	daifclr, #DAIF_ABT_BIT
136
137	/* ---------------------------------------------------------------------
138	 * Initialise CPTR_EL3, setting all fields rather than relying on hw.
139	 * All fields are architecturally UNKNOWN on reset.
140	 *
141	 * CPTR_EL3.TCPAC: Set to zero so that any accesses to CPACR_EL1,
142	 *  CPTR_EL2, CPACR, or HCPTR do not trap to EL3.
143	 *
144	 * CPTR_EL3.TTA: Set to zero so that System register accesses to the
145	 *  trace registers do not trap to EL3.
146	 *
147	 * CPTR_EL3.TFP: Set to zero so that accesses to Advanced SIMD and
148	 *  floating-point functionality do not trap to EL3.
149	 * ---------------------------------------------------------------------
150	 */
151	mov_imm x0, (CPTR_EL3_RESET_VAL & ~(TCPAC_BIT | TTA_BIT | TFP_BIT))
152	msr	cptr_el3, x0
153	.endm
154
155/* -----------------------------------------------------------------------------
156 * This is the super set of actions that need to be performed during a cold boot
157 * or a warm boot in EL3. This code is shared by BL1 and BL31.
158 *
159 * This macro will always perform reset handling, architectural initialisations
160 * and stack setup. The rest of the actions are optional because they might not
161 * be needed, depending on the context in which this macro is called. This is
162 * why this macro is parameterised ; each parameter allows to enable/disable
163 * some actions.
164 *
165 *  _init_sctlr:
166 *	Whether the macro needs to initialise SCTLR_EL3, including configuring
167 *      the endianness of data accesses.
168 *
169 *  _warm_boot_mailbox:
170 *	Whether the macro needs to detect the type of boot (cold/warm). The
171 *	detection is based on the platform entrypoint address : if it is zero
172 *	then it is a cold boot, otherwise it is a warm boot. In the latter case,
173 *	this macro jumps on the platform entrypoint address.
174 *
175 *  _secondary_cold_boot:
176 *	Whether the macro needs to identify the CPU that is calling it: primary
177 *	CPU or secondary CPU. The primary CPU will be allowed to carry on with
178 *	the platform initialisations, while the secondaries will be put in a
179 *	platform-specific state in the meantime.
180 *
181 *	If the caller knows this macro will only be called by the primary CPU
182 *	then this parameter can be defined to 0 to skip this step.
183 *
184 * _init_memory:
185 *	Whether the macro needs to initialise the memory.
186 *
187 * _init_c_runtime:
188 *	Whether the macro needs to initialise the C runtime environment.
189 *
190 * _exception_vectors:
191 *	Address of the exception vectors to program in the VBAR_EL3 register.
192 * -----------------------------------------------------------------------------
193 */
194	.macro el3_entrypoint_common					\
195		_init_sctlr, _warm_boot_mailbox, _secondary_cold_boot,	\
196		_init_memory, _init_c_runtime, _exception_vectors
197
198	.if \_init_sctlr
199		/* -------------------------------------------------------------
200		 * This is the initialisation of SCTLR_EL3 and so must ensure
201		 * that all fields are explicitly set rather than relying on hw.
202		 * Some fields reset to an IMPLEMENTATION DEFINED value and
203		 * others are architecturally UNKNOWN on reset.
204		 *
205		 * SCTLR.EE: Set the CPU endianness before doing anything that
206		 *  might involve memory reads or writes. Set to zero to select
207		 *  Little Endian.
208		 *
209		 * SCTLR_EL3.WXN: For the EL3 translation regime, this field can
210		 *  force all memory regions that are writeable to be treated as
211		 *  XN (Execute-never). Set to zero so that this control has no
212		 *  effect on memory access permissions.
213		 *
214		 * SCTLR_EL3.SA: Set to zero to disable Stack Aligment check.
215		 *
216		 * SCTLR_EL3.A: Set to zero to disable Alignment fault checking.
217		 * -------------------------------------------------------------
218		 */
219		mov_imm	x0, (SCTLR_RESET_VAL & ~(SCTLR_EE_BIT | SCTLR_WXN_BIT \
220				| SCTLR_SA_BIT | SCTLR_A_BIT))
221		msr	sctlr_el3, x0
222		isb
223	.endif /* _init_sctlr */
224
225	.if \_warm_boot_mailbox
226		/* -------------------------------------------------------------
227		 * This code will be executed for both warm and cold resets.
228		 * Now is the time to distinguish between the two.
229		 * Query the platform entrypoint address and if it is not zero
230		 * then it means it is a warm boot so jump to this address.
231		 * -------------------------------------------------------------
232		 */
233		bl	plat_get_my_entrypoint
234		cbz	x0, do_cold_boot
235		br	x0
236
237	do_cold_boot:
238	.endif /* _warm_boot_mailbox */
239
240	/* ---------------------------------------------------------------------
241	 * It is a cold boot.
242	 * Perform any processor specific actions upon reset e.g. cache, TLB
243	 * invalidations etc.
244	 * ---------------------------------------------------------------------
245	 */
246	bl	reset_handler
247
248	el3_arch_init_common \_exception_vectors
249
250	.if \_secondary_cold_boot
251		/* -------------------------------------------------------------
252		 * Check if this is a primary or secondary CPU cold boot.
253		 * The primary CPU will set up the platform while the
254		 * secondaries are placed in a platform-specific state until the
255		 * primary CPU performs the necessary actions to bring them out
256		 * of that state and allows entry into the OS.
257		 * -------------------------------------------------------------
258		 */
259		bl	plat_is_my_cpu_primary
260		cbnz	w0, do_primary_cold_boot
261
262		/* This is a cold boot on a secondary CPU */
263		bl	plat_secondary_cold_boot_setup
264		/* plat_secondary_cold_boot_setup() is not supposed to return */
265		bl	el3_panic
266
267	do_primary_cold_boot:
268	.endif /* _secondary_cold_boot */
269
270	/* ---------------------------------------------------------------------
271	 * Initialize memory now. Secondary CPU initialization won't get to this
272	 * point.
273	 * ---------------------------------------------------------------------
274	 */
275
276	.if \_init_memory
277		bl	platform_mem_init
278	.endif /* _init_memory */
279
280	/* ---------------------------------------------------------------------
281	 * Init C runtime environment:
282	 *   - Zero-initialise the NOBITS sections. There are 2 of them:
283	 *       - the .bss section;
284	 *       - the coherent memory section (if any).
285	 *   - Relocate the data section from ROM to RAM, if required.
286	 * ---------------------------------------------------------------------
287	 */
288	.if \_init_c_runtime
289#ifdef IMAGE_BL31
290		/* -------------------------------------------------------------
291		 * Invalidate the RW memory used by the BL31 image. This
292		 * includes the data and NOBITS sections. This is done to
293		 * safeguard against possible corruption of this memory by
294		 * dirty cache lines in a system cache as a result of use by
295		 * an earlier boot loader stage.
296		 * -------------------------------------------------------------
297		 */
298		adr	x0, __RW_START__
299		adr	x1, __RW_END__
300		sub	x1, x1, x0
301		bl	inv_dcache_range
302#endif /* IMAGE_BL31 */
303
304		ldr	x0, =__BSS_START__
305		ldr	x1, =__BSS_SIZE__
306		bl	zeromem
307
308#if USE_COHERENT_MEM
309		ldr	x0, =__COHERENT_RAM_START__
310		ldr	x1, =__COHERENT_RAM_UNALIGNED_SIZE__
311		bl	zeromem
312#endif
313
314#ifdef IMAGE_BL1
315		ldr	x0, =__DATA_RAM_START__
316		ldr	x1, =__DATA_ROM_START__
317		ldr	x2, =__DATA_SIZE__
318		bl	memcpy16
319#endif
320	.endif /* _init_c_runtime */
321
322	/* ---------------------------------------------------------------------
323	 * Use SP_EL0 for the C runtime stack.
324	 * ---------------------------------------------------------------------
325	 */
326	msr	spsel, #0
327
328	/* ---------------------------------------------------------------------
329	 * Allocate a stack whose memory will be marked as Normal-IS-WBWA when
330	 * the MMU is enabled. There is no risk of reading stale stack memory
331	 * after enabling the MMU as only the primary CPU is running at the
332	 * moment.
333	 * ---------------------------------------------------------------------
334	 */
335	bl	plat_set_my_stack
336
337#if STACK_PROTECTOR_ENABLED
338	.if \_init_c_runtime
339	bl	update_stack_protector_canary
340	.endif /* _init_c_runtime */
341#endif
342	.endm
343
344#endif /* __EL3_COMMON_MACROS_S__ */
345