mirror of
https://github.com/AsahiLinux/u-boot
synced 2024-11-14 17:07:38 +00:00
b5bd09820c
At present CONFIG_SKIP_LOWLEVEL_INIT prevents U-Boot from calling lowlevel_init(). This means that the instruction cache is not enabled and the board runs very slowly. What is really needed in many cases is to skip the call to lowlevel_init() but still perform CP15 init. Add an option to handle this. Reviewed-by: Heiko Schocher <hs@denx.de> Tested-on: smartweb, corvus, taurus, axm Tested-by: Heiko Schocher <hs@denx.de> Reviewed-by: Joe Hershberger <joe.hershberger@ni.com> Signed-off-by: Simon Glass <sjg@chromium.org> Reviewed-by: Andreas Bießmann <andreas@biessmann.org>
102 lines
2.4 KiB
ArmAsm
102 lines
2.4 KiB
ArmAsm
/*
|
|
* armboot - Startup Code for ARM926EJS CPU-core
|
|
*
|
|
* Copyright (c) 2003 Texas Instruments
|
|
*
|
|
* ----- Adapted for OMAP1610 OMAP730 from ARM925t code ------
|
|
*
|
|
* Copyright (c) 2001 Marius Gröger <mag@sysgo.de>
|
|
* Copyright (c) 2002 Alex Züpke <azu@sysgo.de>
|
|
* Copyright (c) 2002 Gary Jennejohn <garyj@denx.de>
|
|
* Copyright (c) 2003 Richard Woodruff <r-woodruff2@ti.com>
|
|
* Copyright (c) 2003 Kshitij <kshitij@ti.com>
|
|
* Copyright (c) 2010 Albert Aribaud <albert.u.boot@aribaud.net>
|
|
*
|
|
* SPDX-License-Identifier: GPL-2.0+
|
|
*/
|
|
|
|
#include <asm-offsets.h>
|
|
#include <config.h>
|
|
|
|
/*
|
|
*************************************************************************
|
|
*
|
|
* Startup Code (reset vector)
|
|
*
|
|
* do important init only if we don't start from memory!
|
|
* setup Memory and board specific bits prior to relocation.
|
|
* relocate armboot to ram
|
|
* setup stack
|
|
*
|
|
*************************************************************************
|
|
*/
|
|
|
|
.globl reset
|
|
|
|
reset:
|
|
/*
|
|
* set the cpu to SVC32 mode
|
|
*/
|
|
mrs r0,cpsr
|
|
bic r0,r0,#0x1f
|
|
orr r0,r0,#0xd3
|
|
msr cpsr,r0
|
|
|
|
/*
|
|
* we do sys-critical inits only at reboot,
|
|
* not when booting from ram!
|
|
*/
|
|
#ifndef CONFIG_SKIP_LOWLEVEL_INIT
|
|
bl cpu_init_crit
|
|
#endif
|
|
|
|
bl _main
|
|
|
|
/*------------------------------------------------------------------------------*/
|
|
|
|
.globl c_runtime_cpu_setup
|
|
c_runtime_cpu_setup:
|
|
|
|
mov pc, lr
|
|
|
|
/*
|
|
*************************************************************************
|
|
*
|
|
* CPU_init_critical registers
|
|
*
|
|
* setup important registers
|
|
* setup memory timing
|
|
*
|
|
*************************************************************************
|
|
*/
|
|
|
|
|
|
#ifndef CONFIG_SKIP_LOWLEVEL_INIT
|
|
cpu_init_crit:
|
|
/*
|
|
* flush v4 I/D caches
|
|
*/
|
|
mov r0, #0
|
|
mcr p15, 0, r0, c7, c5, 0 /* flush v4 I-cache */
|
|
mcr p15, 0, r0, c7, c6, 0 /* flush v4 D-cache */
|
|
|
|
/*
|
|
* disable MMU stuff and caches
|
|
*/
|
|
mrc p15, 0, r0, c1, c0, 0
|
|
bic r0, r0, #0x00002300 /* clear bits 13, 9:8 (--V- --RS) */
|
|
bic r0, r0, #0x00000087 /* clear bits 7, 2:0 (B--- -CAM) */
|
|
orr r0, r0, #0x00000002 /* set bit 1 (A) Align */
|
|
orr r0, r0, #0x00001000 /* set bit 12 (I) I-Cache */
|
|
mcr p15, 0, r0, c1, c0, 0
|
|
|
|
#ifndef CONFIG_SKIP_LOWLEVEL_INIT_ONLY
|
|
/*
|
|
* Go setup Memory and board specific bits prior to relocation.
|
|
*/
|
|
mov ip, lr /* perserve link reg across call */
|
|
bl lowlevel_init /* go setup memory */
|
|
mov lr, ip /* restore link */
|
|
#endif
|
|
mov pc, lr /* back to my caller */
|
|
#endif
|