mirror of
				https://source.denx.de/u-boot/u-boot.git
				synced 2025-10-31 00:11:51 +01:00 
			
		
		
		
	ARM Architecture reference manual clearly states that PE pipeline should be flushed after changes to some system registers. Refer to paragraph "B2.3.5 Memory Barriers" at page B2-92 of "Arm Architecture Reference Manual ARMv8 for ARMv8-A Architecture Profile" (ARM DDI 0487B.a). Failing to issue instruction synchronization barrier can lead to spurious errors, like synchronous exception when accessing FPU registers. This is very prominent on CPUs with long instruction pipeline, like ARM Cortex A72. This change fixes the following U-Boot panic: "Synchronous Abort" handler, esr 0x1fe00000 elr: 00000000800948cc lr : 0000000080091e04 x0 : 00000000801ffdc8 x1 : 00000000000000c8 x2 : 00000000800979d4 x3 : 00000000801ffc60 x4 : 00000000801ffd40 x5 : ffffff80ffffffd8 x6 : 00000000801ffd70 x7 : 00000000801ffd70 x8 : 000000000000000a x9 : 0000000000000000 x10: 0000000000000044 x11: 0000000000000000 x12: 0000000000000000 x13: 0000000000000000 x14: 0000000000000000 x15: 0000000000000000 x16: 000000008008b2e0 x17: 0000000000000000 x18: 00000000801ffec0 x19: 00000000800957b0 x20: 00000000000000c8 x21: 00000000801ffdc8 x22: 000000008009909e x23: 0000000000000000 x24: 0000000000000000 x25: 0000000000000000 x26: 0000000000000000 x27: 0000000000000000 x28: 0000000000000000 x29: 00000000801ffc50 Code: a94417e4 a90217e4 a9051fe6 a90617e4 (3d801fe0) While executing instruction str q0, [sp, #112] in vsnprintf() prologue. This panic was observed only on Cortex A72 so far. This patch places ISBs on other strategic places as well. Also, this probably is the right fix for the issue workarounded in the commit 45f41c134baf ("ARM: uniphier: add weird workaround code for LD20") Reported-by: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com> Suggested-by: Julien Grall <julien.grall.oss@gmail.com> Signed-off-by: Volodymyr Babchuk <volodymyr_babchuk@epam.com> CC: Tom Rini <trini@konsulko.com> CC: Masahiro Yamada <yamada.masahiro@socionext.com> CC: Stefano Stabellini <sstabellini@kernel.org> Reviewed-by: Julien Grall <julien@xen.org> Reviewed-by: Andre Przywara <andre.przywara@arm.com> Tested-by: Masahiro Yamada <yamada.masahiro@socionext.com>
		
			
				
	
	
		
			383 lines
		
	
	
		
			8.2 KiB
		
	
	
	
		
			ArmAsm
		
	
	
	
	
	
			
		
		
	
	
			383 lines
		
	
	
		
			8.2 KiB
		
	
	
	
		
			ArmAsm
		
	
	
	
	
	
| /* SPDX-License-Identifier: GPL-2.0+ */
 | |
| /*
 | |
|  * (C) Copyright 2013
 | |
|  * David Feng <fenghua@phytium.com.cn>
 | |
|  */
 | |
| 
 | |
| #include <asm-offsets.h>
 | |
| #include <config.h>
 | |
| #include <linux/linkage.h>
 | |
| #include <asm/macro.h>
 | |
| #include <asm/armv8/mmu.h>
 | |
| 
 | |
| /*************************************************************************
 | |
|  *
 | |
|  * Startup Code (reset vector)
 | |
|  *
 | |
|  *************************************************************************/
 | |
| 
 | |
| .globl	_start
 | |
| _start:
 | |
| #if defined(CONFIG_LINUX_KERNEL_IMAGE_HEADER)
 | |
| #include <asm/boot0-linux-kernel-header.h>
 | |
| #elif defined(CONFIG_ENABLE_ARM_SOC_BOOT0_HOOK)
 | |
| /*
 | |
|  * Various SoCs need something special and SoC-specific up front in
 | |
|  * order to boot, allow them to set that in their boot0.h file and then
 | |
|  * use it here.
 | |
|  */
 | |
| #include <asm/arch/boot0.h>
 | |
| #else
 | |
| 	b	reset
 | |
| #endif
 | |
| 
 | |
| 	.align 3
 | |
| 
 | |
| .globl	_TEXT_BASE
 | |
| _TEXT_BASE:
 | |
| 	.quad	CONFIG_SYS_TEXT_BASE
 | |
| 
 | |
| /*
 | |
|  * These are defined in the linker script.
 | |
|  */
 | |
| .globl	_end_ofs
 | |
| _end_ofs:
 | |
| 	.quad	_end - _start
 | |
| 
 | |
| .globl	_bss_start_ofs
 | |
| _bss_start_ofs:
 | |
| 	.quad	__bss_start - _start
 | |
| 
 | |
| .globl	_bss_end_ofs
 | |
| _bss_end_ofs:
 | |
| 	.quad	__bss_end - _start
 | |
| 
 | |
| reset:
 | |
| 	/* Allow the board to save important registers */
 | |
| 	b	save_boot_params
 | |
| .globl	save_boot_params_ret
 | |
| save_boot_params_ret:
 | |
| 
 | |
| #if CONFIG_POSITION_INDEPENDENT
 | |
| 	/*
 | |
| 	 * Fix .rela.dyn relocations. This allows U-Boot to be loaded to and
 | |
| 	 * executed at a different address than it was linked at.
 | |
| 	 */
 | |
| pie_fixup:
 | |
| 	adr	x0, _start		/* x0 <- Runtime value of _start */
 | |
| 	ldr	x1, _TEXT_BASE		/* x1 <- Linked value of _start */
 | |
| 	sub	x9, x0, x1		/* x9 <- Run-vs-link offset */
 | |
| 	adr	x2, __rel_dyn_start	/* x2 <- Runtime &__rel_dyn_start */
 | |
| 	adr	x3, __rel_dyn_end	/* x3 <- Runtime &__rel_dyn_end */
 | |
| pie_fix_loop:
 | |
| 	ldp	x0, x1, [x2], #16	/* (x0, x1) <- (Link location, fixup) */
 | |
| 	ldr	x4, [x2], #8		/* x4 <- addend */
 | |
| 	cmp	w1, #1027		/* relative fixup? */
 | |
| 	bne	pie_skip_reloc
 | |
| 	/* relative fix: store addend plus offset at dest location */
 | |
| 	add	x0, x0, x9
 | |
| 	add	x4, x4, x9
 | |
| 	str	x4, [x0]
 | |
| pie_skip_reloc:
 | |
| 	cmp	x2, x3
 | |
| 	b.lo	pie_fix_loop
 | |
| pie_fixup_done:
 | |
| #endif
 | |
| 
 | |
| #ifdef CONFIG_SYS_RESET_SCTRL
 | |
| 	bl reset_sctrl
 | |
| #endif
 | |
| 
 | |
| #if defined(CONFIG_ARMV8_SPL_EXCEPTION_VECTORS) || !defined(CONFIG_SPL_BUILD)
 | |
| .macro	set_vbar, regname, reg
 | |
| 	msr	\regname, \reg
 | |
| .endm
 | |
| 	adr	x0, vectors
 | |
| #else
 | |
| .macro	set_vbar, regname, reg
 | |
| .endm
 | |
| #endif
 | |
| 	/*
 | |
| 	 * Could be EL3/EL2/EL1, Initial State:
 | |
| 	 * Little Endian, MMU Disabled, i/dCache Disabled
 | |
| 	 */
 | |
| 	switch_el x1, 3f, 2f, 1f
 | |
| 3:	set_vbar vbar_el3, x0
 | |
| 	mrs	x0, scr_el3
 | |
| 	orr	x0, x0, #0xf			/* SCR_EL3.NS|IRQ|FIQ|EA */
 | |
| 	msr	scr_el3, x0
 | |
| 	msr	cptr_el3, xzr			/* Enable FP/SIMD */
 | |
| #ifdef COUNTER_FREQUENCY
 | |
| 	ldr	x0, =COUNTER_FREQUENCY
 | |
| 	msr	cntfrq_el0, x0			/* Initialize CNTFRQ */
 | |
| #endif
 | |
| 	b	0f
 | |
| 2:	set_vbar	vbar_el2, x0
 | |
| 	mov	x0, #0x33ff
 | |
| 	msr	cptr_el2, x0			/* Enable FP/SIMD */
 | |
| 	b	0f
 | |
| 1:	set_vbar	vbar_el1, x0
 | |
| 	mov	x0, #3 << 20
 | |
| 	msr	cpacr_el1, x0			/* Enable FP/SIMD */
 | |
| 0:
 | |
| 	isb
 | |
| 
 | |
| 	/*
 | |
| 	 * Enable SMPEN bit for coherency.
 | |
| 	 * This register is not architectural but at the moment
 | |
| 	 * this bit should be set for A53/A57/A72.
 | |
| 	 */
 | |
| #ifdef CONFIG_ARMV8_SET_SMPEN
 | |
| 	switch_el x1, 3f, 1f, 1f
 | |
| 3:
 | |
| 	mrs     x0, S3_1_c15_c2_1               /* cpuectlr_el1 */
 | |
| 	orr     x0, x0, #0x40
 | |
| 	msr     S3_1_c15_c2_1, x0
 | |
| 	isb
 | |
| 1:
 | |
| #endif
 | |
| 
 | |
| 	/* Apply ARM core specific erratas */
 | |
| 	bl	apply_core_errata
 | |
| 
 | |
| 	/*
 | |
| 	 * Cache/BPB/TLB Invalidate
 | |
| 	 * i-cache is invalidated before enabled in icache_enable()
 | |
| 	 * tlb is invalidated before mmu is enabled in dcache_enable()
 | |
| 	 * d-cache is invalidated before enabled in dcache_enable()
 | |
| 	 */
 | |
| 
 | |
| 	/* Processor specific initialization */
 | |
| 	bl	lowlevel_init
 | |
| 
 | |
| #if defined(CONFIG_ARMV8_SPIN_TABLE) && !defined(CONFIG_SPL_BUILD)
 | |
| 	branch_if_master x0, x1, master_cpu
 | |
| 	b	spin_table_secondary_jump
 | |
| 	/* never return */
 | |
| #elif defined(CONFIG_ARMV8_MULTIENTRY)
 | |
| 	branch_if_master x0, x1, master_cpu
 | |
| 
 | |
| 	/*
 | |
| 	 * Slave CPUs
 | |
| 	 */
 | |
| slave_cpu:
 | |
| 	wfe
 | |
| 	ldr	x1, =CPU_RELEASE_ADDR
 | |
| 	ldr	x0, [x1]
 | |
| 	cbz	x0, slave_cpu
 | |
| 	br	x0			/* branch to the given address */
 | |
| #endif /* CONFIG_ARMV8_MULTIENTRY */
 | |
| master_cpu:
 | |
| 	bl	_main
 | |
| 
 | |
| #ifdef CONFIG_SYS_RESET_SCTRL
 | |
| reset_sctrl:
 | |
| 	switch_el x1, 3f, 2f, 1f
 | |
| 3:
 | |
| 	mrs	x0, sctlr_el3
 | |
| 	b	0f
 | |
| 2:
 | |
| 	mrs	x0, sctlr_el2
 | |
| 	b	0f
 | |
| 1:
 | |
| 	mrs	x0, sctlr_el1
 | |
| 
 | |
| 0:
 | |
| 	ldr	x1, =0xfdfffffa
 | |
| 	and	x0, x0, x1
 | |
| 
 | |
| 	switch_el x1, 6f, 5f, 4f
 | |
| 6:
 | |
| 	msr	sctlr_el3, x0
 | |
| 	b	7f
 | |
| 5:
 | |
| 	msr	sctlr_el2, x0
 | |
| 	b	7f
 | |
| 4:
 | |
| 	msr	sctlr_el1, x0
 | |
| 
 | |
| 7:
 | |
| 	dsb	sy
 | |
| 	isb
 | |
| 	b	__asm_invalidate_tlb_all
 | |
| 	ret
 | |
| #endif
 | |
| 
 | |
| /*-----------------------------------------------------------------------*/
 | |
| 
 | |
| WEAK(apply_core_errata)
 | |
| 
 | |
| 	mov	x29, lr			/* Save LR */
 | |
| 	/* For now, we support Cortex-A53, Cortex-A57 specific errata */
 | |
| 
 | |
| 	/* Check if we are running on a Cortex-A53 core */
 | |
| 	branch_if_a53_core x0, apply_a53_core_errata
 | |
| 
 | |
| 	/* Check if we are running on a Cortex-A57 core */
 | |
| 	branch_if_a57_core x0, apply_a57_core_errata
 | |
| 0:
 | |
| 	mov	lr, x29			/* Restore LR */
 | |
| 	ret
 | |
| 
 | |
| apply_a53_core_errata:
 | |
| 
 | |
| #ifdef CONFIG_ARM_ERRATA_855873
 | |
| 	mrs	x0, midr_el1
 | |
| 	tst	x0, #(0xf << 20)
 | |
| 	b.ne	0b
 | |
| 
 | |
| 	mrs	x0, midr_el1
 | |
| 	and	x0, x0, #0xf
 | |
| 	cmp	x0, #3
 | |
| 	b.lt	0b
 | |
| 
 | |
| 	mrs	x0, S3_1_c15_c2_0	/* cpuactlr_el1 */
 | |
| 	/* Enable data cache clean as data cache clean/invalidate */
 | |
| 	orr	x0, x0, #1 << 44
 | |
| 	msr	S3_1_c15_c2_0, x0	/* cpuactlr_el1 */
 | |
| 	isb
 | |
| #endif
 | |
| 	b 0b
 | |
| 
 | |
| apply_a57_core_errata:
 | |
| 
 | |
| #ifdef CONFIG_ARM_ERRATA_828024
 | |
| 	mrs	x0, S3_1_c15_c2_0	/* cpuactlr_el1 */
 | |
| 	/* Disable non-allocate hint of w-b-n-a memory type */
 | |
| 	orr	x0, x0, #1 << 49
 | |
| 	/* Disable write streaming no L1-allocate threshold */
 | |
| 	orr	x0, x0, #3 << 25
 | |
| 	/* Disable write streaming no-allocate threshold */
 | |
| 	orr	x0, x0, #3 << 27
 | |
| 	msr	S3_1_c15_c2_0, x0	/* cpuactlr_el1 */
 | |
| 	isb
 | |
| #endif
 | |
| 
 | |
| #ifdef CONFIG_ARM_ERRATA_826974
 | |
| 	mrs	x0, S3_1_c15_c2_0	/* cpuactlr_el1 */
 | |
| 	/* Disable speculative load execution ahead of a DMB */
 | |
| 	orr	x0, x0, #1 << 59
 | |
| 	msr	S3_1_c15_c2_0, x0	/* cpuactlr_el1 */
 | |
| 	isb
 | |
| #endif
 | |
| 
 | |
| #ifdef CONFIG_ARM_ERRATA_833471
 | |
| 	mrs	x0, S3_1_c15_c2_0	/* cpuactlr_el1 */
 | |
| 	/* FPSCR write flush.
 | |
| 	 * Note that in some cases where a flush is unnecessary this
 | |
| 	    could impact performance. */
 | |
| 	orr	x0, x0, #1 << 38
 | |
| 	msr	S3_1_c15_c2_0, x0	/* cpuactlr_el1 */
 | |
| 	isb
 | |
| #endif
 | |
| 
 | |
| #ifdef CONFIG_ARM_ERRATA_829520
 | |
| 	mrs	x0, S3_1_c15_c2_0	/* cpuactlr_el1 */
 | |
| 	/* Disable Indirect Predictor bit will prevent this erratum
 | |
| 	    from occurring
 | |
| 	 * Note that in some cases where a flush is unnecessary this
 | |
| 	    could impact performance. */
 | |
| 	orr	x0, x0, #1 << 4
 | |
| 	msr	S3_1_c15_c2_0, x0	/* cpuactlr_el1 */
 | |
| 	isb
 | |
| #endif
 | |
| 
 | |
| #ifdef CONFIG_ARM_ERRATA_833069
 | |
| 	mrs	x0, S3_1_c15_c2_0	/* cpuactlr_el1 */
 | |
| 	/* Disable Enable Invalidates of BTB bit */
 | |
| 	and	x0, x0, #0xE
 | |
| 	msr	S3_1_c15_c2_0, x0	/* cpuactlr_el1 */
 | |
| 	isb
 | |
| #endif
 | |
| 	b 0b
 | |
| ENDPROC(apply_core_errata)
 | |
| 
 | |
| /*-----------------------------------------------------------------------*/
 | |
| 
 | |
| WEAK(lowlevel_init)
 | |
| 	mov	x29, lr			/* Save LR */
 | |
| 
 | |
| #if defined(CONFIG_GICV2) || defined(CONFIG_GICV3)
 | |
| 	branch_if_slave x0, 1f
 | |
| 	ldr	x0, =GICD_BASE
 | |
| 	bl	gic_init_secure
 | |
| 1:
 | |
| #if defined(CONFIG_GICV3)
 | |
| 	ldr	x0, =GICR_BASE
 | |
| 	bl	gic_init_secure_percpu
 | |
| #elif defined(CONFIG_GICV2)
 | |
| 	ldr	x0, =GICD_BASE
 | |
| 	ldr	x1, =GICC_BASE
 | |
| 	bl	gic_init_secure_percpu
 | |
| #endif
 | |
| #endif
 | |
| 
 | |
| #ifdef CONFIG_ARMV8_MULTIENTRY
 | |
| 	branch_if_master x0, x1, 2f
 | |
| 
 | |
| 	/*
 | |
| 	 * Slave should wait for master clearing spin table.
 | |
| 	 * This sync prevent salves observing incorrect
 | |
| 	 * value of spin table and jumping to wrong place.
 | |
| 	 */
 | |
| #if defined(CONFIG_GICV2) || defined(CONFIG_GICV3)
 | |
| #ifdef CONFIG_GICV2
 | |
| 	ldr	x0, =GICC_BASE
 | |
| #endif
 | |
| 	bl	gic_wait_for_interrupt
 | |
| #endif
 | |
| 
 | |
| 	/*
 | |
| 	 * All slaves will enter EL2 and optionally EL1.
 | |
| 	 */
 | |
| 	adr	x4, lowlevel_in_el2
 | |
| 	ldr	x5, =ES_TO_AARCH64
 | |
| 	bl	armv8_switch_to_el2
 | |
| 
 | |
| lowlevel_in_el2:
 | |
| #ifdef CONFIG_ARMV8_SWITCH_TO_EL1
 | |
| 	adr	x4, lowlevel_in_el1
 | |
| 	ldr	x5, =ES_TO_AARCH64
 | |
| 	bl	armv8_switch_to_el1
 | |
| 
 | |
| lowlevel_in_el1:
 | |
| #endif
 | |
| 
 | |
| #endif /* CONFIG_ARMV8_MULTIENTRY */
 | |
| 
 | |
| 2:
 | |
| 	mov	lr, x29			/* Restore LR */
 | |
| 	ret
 | |
| ENDPROC(lowlevel_init)
 | |
| 
 | |
| WEAK(smp_kick_all_cpus)
 | |
| 	/* Kick secondary cpus up by SGI 0 interrupt */
 | |
| #if defined(CONFIG_GICV2) || defined(CONFIG_GICV3)
 | |
| 	ldr	x0, =GICD_BASE
 | |
| 	b	gic_kick_secondary_cpus
 | |
| #endif
 | |
| 	ret
 | |
| ENDPROC(smp_kick_all_cpus)
 | |
| 
 | |
| /*-----------------------------------------------------------------------*/
 | |
| 
 | |
| ENTRY(c_runtime_cpu_setup)
 | |
| #if defined(CONFIG_ARMV8_SPL_EXCEPTION_VECTORS) || !defined(CONFIG_SPL_BUILD)
 | |
| 	/* Relocate vBAR */
 | |
| 	adr	x0, vectors
 | |
| 	switch_el x1, 3f, 2f, 1f
 | |
| 3:	msr	vbar_el3, x0
 | |
| 	b	0f
 | |
| 2:	msr	vbar_el2, x0
 | |
| 	b	0f
 | |
| 1:	msr	vbar_el1, x0
 | |
| 0:
 | |
| #endif
 | |
| 
 | |
| 	ret
 | |
| ENDPROC(c_runtime_cpu_setup)
 | |
| 
 | |
| WEAK(save_boot_params)
 | |
| 	b	save_boot_params_ret	/* back to my caller */
 | |
| ENDPROC(save_boot_params)
 |