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authorDavid Feng <fenghua@phytium.com.cn>2013-12-14 11:47:35 +0800
committerAlbert ARIBAUD <albert.u.boot@aribaud.net>2014-01-09 16:08:44 +0100
commit0ae7653128c80a4f2920cbe9b124792c2fd9d9e0 (patch)
tree14fea7a80e4ea84c7b6a3bc32298daeec55054c7 /arch/arm/cpu/armv8/start.S
parent54799e4596bf8af33fd4a8dee153be7011c06d8d (diff)
arm64: core support
Relocation code based on a patch by Scott Wood, which is: Signed-off-by: Scott Wood <scottwood@freescale.com> Signed-off-by: David Feng <fenghua@phytium.com.cn>
Diffstat (limited to 'arch/arm/cpu/armv8/start.S')
-rw-r--r--arch/arm/cpu/armv8/start.S164
1 files changed, 164 insertions, 0 deletions
diff --git a/arch/arm/cpu/armv8/start.S b/arch/arm/cpu/armv8/start.S
new file mode 100644
index 0000000000..bcc2603098
--- /dev/null
+++ b/arch/arm/cpu/armv8/start.S
@@ -0,0 +1,164 @@
+/*
+ * (C) Copyright 2013
+ * David Feng <fenghua@phytium.com.cn>
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ */
+
+#include <asm-offsets.h>
+#include <config.h>
+#include <version.h>
+#include <linux/linkage.h>
+#include <asm/macro.h>
+#include <asm/armv8/mmu.h>
+
+/*************************************************************************
+ *
+ * Startup Code (reset vector)
+ *
+ *************************************************************************/
+
+.globl _start
+_start:
+ b reset
+
+ .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:
+ /*
+ * Could be EL3/EL2/EL1, Initial State:
+ * Little Endian, MMU Disabled, i/dCache Disabled
+ */
+ adr x0, vectors
+ switch_el x1, 3f, 2f, 1f
+3: msr vbar_el3, x0
+ msr cptr_el3, xzr /* Enable FP/SIMD */
+ ldr x0, =COUNTER_FREQUENCY
+ msr cntfrq_el0, x0 /* Initialize CNTFRQ */
+ b 0f
+2: msr vbar_el2, x0
+ mov x0, #0x33ff
+ msr cptr_el2, x0 /* Enable FP/SIMD */
+ b 0f
+1: msr vbar_el1, x0
+ mov x0, #3 << 20
+ msr cpacr_el1, x0 /* Enable FP/SIMD */
+0:
+
+ /* Cache/BPB/TLB Invalidate */
+ bl __asm_flush_dcache_all /* dCache clean&invalidate */
+ bl __asm_invalidate_icache_all /* iCache invalidate */
+ bl __asm_invalidate_tlb_all /* invalidate TLBs */
+
+ /* Processor specific initialization */
+ bl lowlevel_init
+
+ 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 */
+
+ /*
+ * Master CPU
+ */
+master_cpu:
+ bl _main
+
+/*-----------------------------------------------------------------------*/
+
+WEAK(lowlevel_init)
+ /* Initialize GIC Secure Bank Status */
+ mov x29, lr /* Save LR */
+ bl gic_init
+
+ branch_if_master x0, x1, 1f
+
+ /*
+ * Slave should wait for master clearing spin table.
+ * This sync prevent salves observing incorrect
+ * value of spin table and jumping to wrong place.
+ */
+ bl wait_for_wakeup
+
+ /*
+ * All processors will enter EL2 and optionally EL1.
+ */
+ bl armv8_switch_to_el2
+#ifdef CONFIG_ARMV8_SWITCH_TO_EL1
+ bl armv8_switch_to_el1
+#endif
+
+1:
+ mov lr, x29 /* Restore LR */
+ ret
+ENDPROC(lowlevel_init)
+
+/*-----------------------------------------------------------------------*/
+
+ENTRY(c_runtime_cpu_setup)
+ /* If I-cache is enabled invalidate it */
+#ifndef CONFIG_SYS_ICACHE_OFF
+ ic iallu /* I+BTB cache invalidate */
+ isb sy
+#endif
+
+#ifndef CONFIG_SYS_DCACHE_OFF
+ /*
+ * Setup MAIR and TCR.
+ */
+ ldr x0, =MEMORY_ATTRIBUTES
+ ldr x1, =TCR_FLAGS
+
+ switch_el x2, 3f, 2f, 1f
+3: orr x1, x1, TCR_EL3_IPS_BITS
+ msr mair_el3, x0
+ msr tcr_el3, x1
+ b 0f
+2: orr x1, x1, TCR_EL2_IPS_BITS
+ msr mair_el2, x0
+ msr tcr_el2, x1
+ b 0f
+1: orr x1, x1, TCR_EL1_IPS_BITS
+ msr mair_el1, x0
+ msr tcr_el1, x1
+0:
+#endif
+
+ /* 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:
+
+ ret
+ENDPROC(c_runtime_cpu_setup)