Commit 3971cdc2 authored by Vineet Gupta's avatar Vineet Gupta

ARC: boot: Support Halt-on-reset and Run-on-reset SMP booting modes

For Run-on-reset, non masters need to spin wait. For Halt-on-reset they
can jump to entry point directly.

Also while at it, made reset vector handler as "the" entry point for
kernel including host debugger based boot (which uses the ELF header
entry point)
Signed-off-by: default avatarVineet Gupta <vgupta@synopsys.com>
parent f33e9c43
......@@ -194,6 +194,16 @@ config NR_CPUS
range 2 4096
default "4"
config ARC_SMP_HALT_ON_RESET
bool "Enable Halt-on-reset boot mode"
default y if ARC_UBOOT_SUPPORT
help
In SMP configuration cores can be configured as Halt-on-reset
or they could all start at same time. For Halt-on-reset, non
masters are parked until Master kicks them so they can start of
at designated entry point. For other case, all jump to common
entry point and spin wait for Master's signal.
endif #SMP
menuconfig ARC_CACHE
......
......@@ -24,7 +24,7 @@
.align 4
# Initial 16 slots are Exception Vectors
VECTOR stext ; Restart Vector (jump to entry point)
VECTOR res_service ; Reset Vector
VECTOR mem_service ; Mem exception
VECTOR instr_service ; Instrn Error
VECTOR EV_MachineCheck ; Fatal Machine check
......
......@@ -86,7 +86,7 @@
*/
; ********* Critical System Events **********************
VECTOR res_service ; 0x0, Restart Vector (0x0)
VECTOR res_service ; 0x0, Reset Vector (0x0)
VECTOR mem_service ; 0x8, Mem exception (0x1)
VECTOR instr_service ; 0x10, Instrn Error (0x2)
......@@ -155,13 +155,9 @@ int2_saved_reg:
; ---------------------------------------------
.section .text, "ax",@progbits
res_service: ; processor restart
flag 0x1 ; not implemented
nop
nop
reserved: ; processor restart
rtie ; jump to processor initializations
reserved:
flag 1 ; Unexpected event, halt
;##################### Interrupt Handling ##############################
......
......@@ -50,28 +50,37 @@
.endm
.section .init.text, "ax",@progbits
.type stext, @function
.globl stext
stext:
;-------------------------------------------------------------------
; Don't clobber r0-r2 yet. It might have bootloader provided info
;-------------------------------------------------------------------
;----------------------------------------------------------------
; Default Reset Handler (jumped into from Reset vector)
; - Don't clobber r0,r1,r2 as they might have u-boot provided args
; - Platforms can override this weak version if needed
;----------------------------------------------------------------
WEAK(res_service)
j stext
END(res_service)
;----------------------------------------------------------------
; Kernel Entry point
;----------------------------------------------------------------
ENTRY(stext)
CPU_EARLY_SETUP
#ifdef CONFIG_SMP
; Ensure Boot (Master) proceeds. Others wait in platform dependent way
; IDENTITY Reg [ 3 2 1 0 ]
; (cpu-id) ^^^ => Zero for UP ARC700
; => #Core-ID if SMP (Master 0)
; Note that non-boot CPUs might not land here if halt-on-reset and
; instead breath life from @first_lines_of_secondary, but we still
; need to make sure only boot cpu takes this path.
GET_CPU_ID r5
cmp r5, 0
mov.ne r0, r5
jne arc_platform_smp_wait_to_boot
mov.nz r0, r5
#ifdef CONFIG_ARC_SMP_HALT_ON_RESET
; Non-Master can proceed as system would be booted sufficiently
jnz first_lines_of_secondary
#else
; Non-Masters wait for Master to boot enough and bring them up
jnz arc_platform_smp_wait_to_boot
#endif
; Master falls thru
#endif
; Clear BSS before updating any globals
; XXX: use ZOL here
mov r5, __bss_start
......@@ -102,16 +111,14 @@ stext:
GET_TSK_STACK_BASE r9, sp ; r9 = tsk, sp = stack base(output)
j start_kernel ; "C" entry point
END(stext)
#ifdef CONFIG_SMP
;----------------------------------------------------------------
; First lines of code run by secondary before jumping to 'C'
;----------------------------------------------------------------
.section .text, "ax",@progbits
.type first_lines_of_secondary, @function
.globl first_lines_of_secondary
first_lines_of_secondary:
ENTRY(first_lines_of_secondary)
CPU_EARLY_SETUP
......@@ -126,5 +133,5 @@ first_lines_of_secondary:
GET_TSK_STACK_BASE r0, sp
j start_kernel_secondary
END(first_lines_of_secondary)
#endif
......@@ -12,7 +12,7 @@
#include <asm/thread_info.h>
OUTPUT_ARCH(arc)
ENTRY(_stext)
ENTRY(res_service)
#ifdef CONFIG_CPU_BIG_ENDIAN
jiffies = jiffies_64 + 4;
......
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