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-rw-r--r--arch/arc/kernel/head.S80
1 files changed, 51 insertions, 29 deletions
diff --git a/arch/arc/kernel/head.S b/arch/arc/kernel/head.S
index 0f944f02451..4d2481bd8b9 100644
--- a/arch/arc/kernel/head.S
+++ b/arch/arc/kernel/head.S
@@ -12,10 +12,42 @@
* to skip certain things during boot on simulator
*/
+#include <linux/linkage.h>
#include <asm/asm-offsets.h>
#include <asm/entry.h>
-#include <linux/linkage.h>
#include <asm/arcregs.h>
+#include <asm/cache.h>
+
+.macro CPU_EARLY_SETUP
+
+ ; Setting up Vectror Table (in case exception happens in early boot
+ sr @_int_vec_base_lds, [AUX_INTR_VEC_BASE]
+
+ ; Disable I-cache/D-cache if kernel so configured
+ lr r5, [ARC_REG_IC_BCR]
+ breq r5, 0, 1f ; I$ doesn't exist
+ lr r5, [ARC_REG_IC_CTRL]
+#ifdef CONFIG_ARC_HAS_ICACHE
+ bclr r5, r5, 0 ; 0 - Enable, 1 is Disable
+#else
+ bset r5, r5, 0 ; I$ exists, but is not used
+#endif
+ sr r5, [ARC_REG_IC_CTRL]
+
+1:
+ lr r5, [ARC_REG_DC_BCR]
+ breq r5, 0, 1f ; D$ doesn't exist
+ lr r5, [ARC_REG_DC_CTRL]
+ bclr r5, r5, 6 ; Invalidate (discard w/o wback)
+#ifdef CONFIG_ARC_HAS_DCACHE
+ bclr r5, r5, 0 ; Enable (+Inv)
+#else
+ bset r5, r5, 0 ; Disable (+Inv)
+#endif
+ sr r5, [ARC_REG_DC_CTRL]
+
+1:
+.endm
.cpu A7
@@ -24,13 +56,13 @@
.globl stext
stext:
;-------------------------------------------------------------------
- ; Don't clobber r0-r4 yet. It might have bootloader provided info
+ ; Don't clobber r0-r2 yet. It might have bootloader provided info
;-------------------------------------------------------------------
- sr @_int_vec_base_lds, [AUX_INTR_VEC_BASE]
+ CPU_EARLY_SETUP
#ifdef CONFIG_SMP
- ; Only Boot (Master) proceeds. Others wait in platform dependent way
+ ; 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)
@@ -39,35 +71,25 @@ stext:
; need to make sure only boot cpu takes this path.
GET_CPU_ID r5
cmp r5, 0
- jnz arc_platform_smp_wait_to_boot
+ mov.ne r0, r5
+ jne arc_platform_smp_wait_to_boot
#endif
; Clear BSS before updating any globals
; XXX: use ZOL here
mov r5, __bss_start
- mov r6, __bss_stop
-1:
- st.ab 0, [r5,4]
- brlt r5, r6, 1b
-
-#ifdef CONFIG_CMDLINE_UBOOT
- ; support for bootloader provided cmdline
- ; If cmdline passed by u-boot, then
- ; r0 = 1 (because ATAGS parsing, now retired, used to use 0)
- ; r1 = magic number (board identity)
- ; r2 = addr of cmdline string (somewhere in memory/flash)
-
- brne r0, 1, .Lother_bootup_chores ; u-boot didn't pass cmdline
- breq r2, 0, .Lother_bootup_chores ; or cmdline is NULL
-
- mov r5, @command_line
+ sub r6, __bss_stop, r5
+ lsr.f lp_count, r6, 2
+ lpnz 1f
+ st.ab 0, [r5, 4]
1:
- ldb.ab r6, [r2, 1]
- breq r6, 0, .Lother_bootup_chores
- b.d 1b
- stb.ab r6, [r5, 1]
-#endif
-.Lother_bootup_chores:
+ ; Uboot - kernel ABI
+ ; r0 = [0] No uboot interaction, [1] cmdline in r2, [2] DTB in r2
+ ; r1 = magic number (board identity, unused as of now
+ ; r2 = pointer to uboot provided cmdline or external DTB in mem
+ ; These are handled later in setup_arch()
+ st r0, [@uboot_tag]
+ st r2, [@uboot_arg]
; Identify if running on ISS vs Silicon
; IDENTITY Reg [ 3 2 1 0 ]
@@ -95,13 +117,13 @@ stext:
;----------------------------------------------------------------
; First lines of code run by secondary before jumping to 'C'
;----------------------------------------------------------------
- .section .init.text, "ax",@progbits
+ .section .text, "ax",@progbits
.type first_lines_of_secondary, @function
.globl first_lines_of_secondary
first_lines_of_secondary:
- sr @_int_vec_base_lds, [AUX_INTR_VEC_BASE]
+ CPU_EARLY_SETUP
; setup per-cpu idle task as "current" on this CPU
ld r0, [@secondary_idle_tsk]