/* * armboot - Startup Code for ARM926EJS CPU-core * * Copyright (c) 2003 Texas Instruments * * ----- Adapted for OMAP1610 OMAP730 from ARM925t code ------ * * Copyright (c) 2001 Marius Gröger * Copyright (c) 2002 Alex Züpke * Copyright (c) 2002 Gary Jennejohn * Copyright (c) 2003 Richard Woodruff * Copyright (c) 2003 Kshitij * Copyright (c) 2010 Albert Aribaud * * SPDX-License-Identifier: GPL-2.0+ */ #include #include #include #include /* ************************************************************************* * * 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: bx lr /* ************************************************************************* * * CPU_init_critical registers * * setup important registers * setup memory timing * ************************************************************************* */ #ifndef CONFIG_SKIP_LOWLEVEL_INIT cpu_init_crit: /* * flush D cache before disabling it */ mov r0, #0 flush_dcache: mrc p15, 0, r15, c7, c10, 3 bne flush_dcache mcr p15, 0, r0, c8, c7, 0 /* invalidate TLB */ mcr p15, 0, r0, c7, c5, 0 /* invalidate I Cache */ /* * disable MMU and D cache * enable I cache if CONFIG_SYS_ICACHE_OFF is not defined */ mrc p15, 0, r0, c1, c0, 0 bic r0, r0, #0x00000300 /* clear bits 9:8 (---- --RS) */ bic r0, r0, #0x00000087 /* clear bits 7, 2:0 (B--- -CAM) */ #ifdef CONFIG_SYS_EXCEPTION_VECTORS_HIGH orr r0, r0, #0x00002000 /* set bit 13 (--V- ----) */ #else bic r0, r0, #0x00002000 /* clear bit 13 (--V- ----) */ #endif orr r0, r0, #0x00000002 /* set bit 2 (A) Align */ #ifndef CONFIG_SYS_ICACHE_OFF orr r0, r0, #0x00001000 /* set bit 12 (I) I-Cache */ #endif mcr p15, 0, r0, c1, c0, 0 /* * Go setup Memory and board specific bits prior to relocation. */ mov ip, lr /* perserve link reg across call */ bl lowlevel_init /* go setup pll,mux,memory */ mov lr, ip /* restore link */ mov pc, lr /* back to my caller */ #endif /* CONFIG_SKIP_LOWLEVEL_INIT */