u-boot/arch/arc/lib/start.S
Alexey Brodkin ef639e6f70 arc: significant cache rework
[1] Align cache management functions to those in Linux kernel. I.e.:
    a) Use the same functions for all cache ops (D$ Inv/Flush)
    b) Split cache ops in 3 sub-functions: "before", "lineloop" and
"after". That way we may re-use "before" and "after" functions for
region and full cache ops.

 [2] Implement full-functional L2 (SLC) management. Before SLC was
simply disabled early on boot. It's also possible to enable or disable
L2 cache from config utility.

 [3] Disable/enable corresponding caches early on boot. So if U-Boot is
configured to use caches they will be used at all times (this is useful
in partucular for speed-up of relocation).

Signed-off-by: Alexey Brodkin <abrodkin@synopsys.com>
2015-07-01 17:17:27 +03:00

91 lines
2.1 KiB
ArmAsm

/*
* Copyright (C) 2013-2014 Synopsys, Inc. All rights reserved.
*
* SPDX-License-Identifier: GPL-2.0+
*/
#include <asm-offsets.h>
#include <config.h>
#include <linux/linkage.h>
#include <asm/arcregs.h>
ENTRY(_start)
/* Setup interrupt vector base that matches "__text_start" */
sr __ivt_start, [ARC_AUX_INTR_VEC_BASE]
; Disable/enable I-cache according to configuration
lr r5, [ARC_BCR_IC_BUILD]
breq r5, 0, 1f ; I$ doesn't exist
lr r5, [ARC_AUX_IC_CTRL]
#ifndef CONFIG_SYS_ICACHE_OFF
bclr r5, r5, 0 ; 0 - Enable, 1 is Disable
#else
bset r5, r5, 0 ; I$ exists, but is not used
#endif
sr r5, [ARC_AUX_IC_CTRL]
1:
; Disable/enable D-cache according to configuration
lr r5, [ARC_BCR_DC_BUILD]
breq r5, 0, 1f ; D$ doesn't exist
lr r5, [ARC_AUX_DC_CTRL]
bclr r5, r5, 6 ; Invalidate (discard w/o wback)
#ifndef CONFIG_SYS_DCACHE_OFF
bclr r5, r5, 0 ; Enable (+Inv)
#else
bset r5, r5, 0 ; Disable (+Inv)
#endif
sr r5, [ARC_AUX_DC_CTRL]
1:
#ifdef CONFIG_ISA_ARCV2
; Disable System-Level Cache (SLC)
lr r5, [ARC_BCR_SLC]
breq r5, 0, 1f ; SLC doesn't exist
lr r5, [ARC_AUX_SLC_CTRL]
bclr r5, r5, 6 ; Invalidate (discard w/o wback)
bclr r5, r5, 0 ; Enable (+Inv)
sr r5, [ARC_AUX_SLC_CTRL]
1:
#endif
/* Setup stack- and frame-pointers */
mov %sp, CONFIG_SYS_INIT_SP_ADDR
mov %fp, %sp
/* Allocate and zero GD, update SP */
mov %r0, %sp
bl board_init_f_mem
/* Update stack- and frame-pointers */
mov %sp, %r0
mov %fp, %sp
/* Zero the one and only argument of "board_init_f" */
mov_s %r0, 0
j board_init_f
ENDPROC(_start)
/*
* void board_init_f_r_trampoline(stack-pointer address)
*
* This "function" does not return, instead it continues in RAM
* after relocating the monitor code.
*
* r0 = new stack-pointer
*/
ENTRY(board_init_f_r_trampoline)
/* Set up the stack- and frame-pointers */
mov %sp, %r0
mov %fp, %sp
/* Update position of intterupt vector table */
lr %r0, [ARC_AUX_INTR_VEC_BASE]
ld %r1, [%r25, GD_RELOC_OFF]
add %r0, %r0, %r1
sr %r0, [ARC_AUX_INTR_VEC_BASE]
/* Re-enter U-Boot by calling board_init_f_r */
j board_init_f_r
ENDPROC(board_init_f_r_trampoline)