From: Daniel Schwierzeck <daniel.schwierzeck@gmail.com>
Date: Thu, 20 Nov 2014 22:55:32 +0000 (+0100)
Subject: MIPS: fix setup of initial stack frame
X-Git-Tag: v2015.01-rc3~45^2~7
X-Git-Url: https://git.librecmc.org/?a=commitdiff_plain;h=6d08e22acad9c5890300e7a9e4d077803709339d;p=oweals%2Fu-boot.git

MIPS: fix setup of initial stack frame

To get correct stack walking and backtrace functionality in gdb,
registers fp and ra should be initialized before calling board_init_f
or board_init_r. Thus allocating stack space and zeroing it as it is
currently done in board.c becomes obsolete.

Signed-off-by: Daniel Schwierzeck <daniel.schwierzeck@gmail.com>
---

diff --git a/arch/mips/cpu/mips32/start.S b/arch/mips/cpu/mips32/start.S
index 68e59b596f..384ea26022 100644
--- a/arch/mips/cpu/mips32/start.S
+++ b/arch/mips/cpu/mips32/start.S
@@ -136,10 +136,11 @@ reset:
 
 	/* Set up temporary stack */
 	li	sp, CONFIG_SYS_SDRAM_BASE + CONFIG_SYS_INIT_SP_OFFSET
+	move	fp, sp
 
 	la	t9, board_init_f
 	jr	t9
-	 nop
+	 move	ra, zero
 
 /*
  * void relocate_code (addr_sp, gd, addr_moni)
@@ -155,6 +156,7 @@ reset:
 	.ent	relocate_code
 relocate_code:
 	move	sp, a0			# set new stack pointer
+	move	fp, sp
 
 	move	s0, a1			# save gd in s0
 	move	s2, a2			# save destination address in s2
@@ -260,8 +262,9 @@ in_ram:
 	 addi	t1, 4
 
 	move	a0, s0			# a0 <-- gd
+	move	a1, s2
 	la	t9, board_init_r
 	jr	t9
-	 move	a1, s2
+	 move	ra, zero
 
 	.end	relocate_code
diff --git a/arch/mips/cpu/mips64/start.S b/arch/mips/cpu/mips64/start.S
index 92954e1c90..6ff714e8ed 100644
--- a/arch/mips/cpu/mips64/start.S
+++ b/arch/mips/cpu/mips64/start.S
@@ -130,10 +130,11 @@ reset:
 
 	/* Set up temporary stack */
 	dli	sp, CONFIG_SYS_SDRAM_BASE + CONFIG_SYS_INIT_SP_OFFSET
+	move	fp, sp
 
 	dla	t9, board_init_f
 	jr	t9
-	 nop
+	 move	ra, zero
 
 /*
  * void relocate_code (addr_sp, gd, addr_moni)
@@ -149,6 +150,7 @@ reset:
 	.ent	relocate_code
 relocate_code:
 	move	sp, a0			# set new stack pointer
+	move	fp, sp
 
 	move	s0, a1			# save gd in s0
 	move	s2, a2			# save destination address in s2
@@ -254,8 +256,9 @@ in_ram:
 	 daddi	t1, 8
 
 	move	a0, s0			# a0 <-- gd
+	move	a1, s2
 	dla	t9, board_init_r
 	jr	t9
-	 move	a1, s2
+	 move	ra, zero
 
 	.end	relocate_code