arc: add cpu files

Signed-off-by: Alexey Brodkin <abrodkin@synopsys.com>

Cc: Vineet Gupta <vgupta@synopsys.com>
Cc: Francois Bedard <fbedard@synopsys.com>
Cc: Wolfgang Denk <wd@denx.de>
Cc: Heiko Schocher <hs@denx.de>

1 files changed, 241 insertions, 0 deletions

diff --git a/arch/arc/cpu/arc700/start.S b/arch/arc/cpu/arc700/start.S
new file mode 100644
index 0000000..563513b
--- /dev/null
+++ b/arch/arc/cpu/arc700/start.S
@@ -0,0 +1,241 @@
+/*
+ * Copyright (C) 2013-2014 Synopsys, Inc. All rights reserved.
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+#include <asm-offsets.h>
+#include <config.h>
+#include <asm/arcregs.h>
+
+/*
+ * Note on the LD/ST addressing modes with address register write-back
+ *
+ * LD.a same as LD.aw
+ *
+ * LD.a    reg1, [reg2, x]  => Pre Incr
+ *      Eff Addr for load = [reg2 + x]
+ *
+ * LD.ab   reg1, [reg2, x]  => Post Incr
+ *      Eff Addr for load = [reg2]
+ */
+
+.macro PUSH reg
+	st.a	\reg, [%sp, -4]
+.endm
+
+.macro PUSHAX aux
+	lr	%r9, [\aux]
+	PUSH	%r9
+.endm
+
+.macro  SAVE_R1_TO_R24
+	PUSH	%r1
+	PUSH	%r2
+	PUSH	%r3
+	PUSH	%r4
+	PUSH	%r5
+	PUSH	%r6
+	PUSH	%r7
+	PUSH	%r8
+	PUSH	%r9
+	PUSH	%r10
+	PUSH	%r11
+	PUSH	%r12
+	PUSH	%r13
+	PUSH	%r14
+	PUSH	%r15
+	PUSH	%r16
+	PUSH	%r17
+	PUSH	%r18
+	PUSH	%r19
+	PUSH	%r20
+	PUSH	%r21
+	PUSH	%r22
+	PUSH	%r23
+	PUSH	%r24
+.endm
+
+.macro SAVE_ALL_SYS
+
+	st	%r0, [%sp]
+	lr	%r0, [%ecr]
+	st	%r0, [%sp, 8]	/* ECR */
+	st	%sp, [%sp, 4]
+
+	SAVE_R1_TO_R24
+	PUSH	%r25
+	PUSH	%gp
+	PUSH	%fp
+	PUSH	%blink
+	PUSHAX	%eret
+	PUSHAX	%erstatus
+	PUSH	%lp_count
+	PUSHAX	%lp_end
+	PUSHAX	%lp_start
+	PUSHAX	%erbta
+.endm
+
+.align 4
+.globl _start
+_start:
+	/* Critical system events */
+	j	reset			/* 0 - 0x000 */
+	j	memory_error		/* 1 - 0x008 */
+	j	instruction_error	/* 2 - 0x010 */
+
+	/* Device interrupts */
+.rept	29
+	j	interrupt_handler	/* 3:31 - 0x018:0xF8 */
+.endr
+	/* Exceptions */
+	j	EV_MachineCheck		/* 0x100, Fatal Machine check  (0x20) */
+	j	EV_TLBMissI		/* 0x108, Intruction TLB miss  (0x21) */
+	j	EV_TLBMissD		/* 0x110, Data TLB miss        (0x22) */
+	j	EV_TLBProtV		/* 0x118, Protection Violation (0x23)
+							or Misaligned Access  */
+	j	EV_PrivilegeV		/* 0x120, Privilege Violation  (0x24) */
+	j	EV_Trap			/* 0x128, Trap exception       (0x25) */
+	j	EV_Extension		/* 0x130, Extn Intruction Excp (0x26) */
+
+memory_error:
+	SAVE_ALL_SYS
+	lr	%r0, [%efa]
+	mov	%r1, %sp
+	j	do_memory_error
+
+instruction_error:
+	SAVE_ALL_SYS
+	lr	%r0, [%efa]
+	mov	%r1, %sp
+	j	do_instruction_error
+
+interrupt_handler:
+	/* Todo - save and restore CPU context when interrupts will be in use */
+	bl	do_interrupt_handler
+	rtie
+
+EV_MachineCheck:
+	SAVE_ALL_SYS
+	lr	%r0, [%efa]
+	mov	%r1, %sp
+	j	do_machine_check_fault
+
+EV_TLBMissI:
+	SAVE_ALL_SYS
+	mov	%r0, %sp
+	j	do_itlb_miss
+
+EV_TLBMissD:
+	SAVE_ALL_SYS
+	mov	%r0, %sp
+	j	do_dtlb_miss
+
+EV_TLBProtV:
+	SAVE_ALL_SYS
+	lr	%r0, [%efa]
+	mov	%r1, %sp
+	j	do_tlb_prot_violation
+
+EV_PrivilegeV:
+	SAVE_ALL_SYS
+	mov	%r0, %sp
+	j	do_privilege_violation
+
+EV_Trap:
+	SAVE_ALL_SYS
+	mov	%r0, %sp
+	j	do_trap
+
+EV_Extension:
+	SAVE_ALL_SYS
+	mov	%r0, %sp
+	j	do_extension
+
+
+reset:
+	/* Setup interrupt vector base that matches "__text_start" */
+	sr	__text_start, [ARC_AUX_INTR_VEC_BASE]
+
+	/* Setup stack pointer */
+	mov	%sp, CONFIG_SYS_INIT_SP_ADDR
+	mov	%fp, %sp
+
+	/* Clear bss */
+	mov	%r0, __bss_start
+	mov	%r1, __bss_end
+
+clear_bss:
+	st.ab	0, [%r0, 4]
+	brlt	%r0, %r1, clear_bss
+
+	/* Zero the one and only argument of "board_init_f" */
+	mov_s	%r0, 0
+	j	board_init_f
+
+/*
+ * void relocate_code (addr_sp, gd, addr_moni)
+ *
+ * This "function" does not return, instead it continues in RAM
+ * after relocating the monitor code.
+ *
+ * r0 = start_addr_sp
+ * r1 = new__gd
+ * r2 = relocaddr
+ */
+.align 4
+.globl	relocate_code
+relocate_code:
+	/*
+	 * r0-r12 might be clobbered by C functions
+	 * so we use r13-r16 for storage here
+	 */
+	mov	%r13, %r0		/* save addr_sp */
+	mov	%r14, %r1		/* save addr of gd */
+	mov	%r15, %r2		/* save addr of destination */
+
+	mov	%r16, %r2		/* %r9 - relocation offset */
+	sub	%r16, %r16, __image_copy_start
+
+/* Set up the stack */
+stack_setup:
+	mov	%sp, %r13
+	mov	%fp, %sp
+
+/* Check if monitor is loaded right in place for relocation */
+	mov	%r0, __image_copy_start
+	cmp	%r0, %r15		/* skip relocation if code loaded */
+	bz	do_board_init_r		/* in target location already */
+
+/* Copy data (__image_copy_start - __image_copy_end) to new location */
+	mov	%r1, %r15
+	mov	%r2, __image_copy_end
+	sub	%r2, %r2, %r0		/* r3 <- amount of bytes to copy */
+	asr	%r2, %r2, 2		/* r3 <- amount of words to copy */
+	mov	%lp_count, %r2
+	lp	copy_end
+	ld.ab	%r2,[%r0,4]
+	st.ab	%r2,[%r1,4]
+copy_end:
+
+/* Fix relocations related issues */
+	bl	do_elf_reloc_fixups
+#ifndef CONFIG_SYS_ICACHE_OFF
+	bl	invalidate_icache_all
+#endif
+#ifndef CONFIG_SYS_DCACHE_OFF
+	bl	flush_dcache_all
+#endif
+
+/* Update position of intterupt vector table */
+	lr	%r0, [ARC_AUX_INTR_VEC_BASE]	/* Read current position */
+	add	%r0, %r0, %r16			/* Update address */
+	sr	%r0, [ARC_AUX_INTR_VEC_BASE]	/* Write new position */
+
+do_board_init_r:
+/* Prepare for exection of "board_init_r" in relocated monitor */
+	mov	%r2, board_init_r	/* old address of "board_init_r()" */
+	add	%r2, %r2, %r16		/* new address of "board_init_r()" */
+	mov	%r0, %r14		/* 1-st parameter: gd_t */
+	mov	%r1, %r15		/* 2-nd parameter: dest_addr */
+	j	[%r2]