/* SPDX-License-Identifier: GPL-2.0+ */ /* * 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 */ #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 .globl save_boot_params_ret .type save_boot_params_ret,%function reset: /* Allow the board to save important registers */ b save_boot_params save_boot_params_ret: /* * 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! */ #if !CONFIG_IS_ENABLED(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 * ************************************************************************* */ #if !CONFIG_IS_ENABLED(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 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 1 (A) Align */ #if !CONFIG_IS_ENABLED(SYS_ICACHE_OFF) orr r0, r0, #0x00001000 /* set bit 12 (I) I-Cache */ #endif mcr p15, 0, r0, c1, c0, 0 #if !CONFIG_IS_ENABLED(SKIP_LOWLEVEL_INIT_ONLY) /* * Go setup Memory and board specific bits prior to relocation. */ mov r4, lr /* perserve link reg across call */ bl lowlevel_init /* go setup pll,mux,memory */ mov lr, r4 /* restore link */ #endif mov pc, lr /* back to my caller */ #endif /* CONFIG_IS_ENABLED(SKIP_LOWLEVEL_INIT) */ /************************************************************************* * * void save_boot_params(u32 r0, u32 r1, u32 r2, u32 r3) * __attribute__((weak)); * * Stack pointer is not yet initialized at this moment * Don't save anything to stack even if compiled with -O0 * *************************************************************************/ WEAK(save_boot_params) b save_boot_params_ret /* back to my caller */ ENDPROC(save_boot_params)