From 8f338f9b44af5f4fa24abf70f5fd4ce8861fc256 Mon Sep 17 00:00:00 2001 From: David Given Date: Wed, 22 May 2013 22:46:10 +0100 Subject: [PATCH] Now actually runs on real hardware. --HG-- branch : dtrg-videocore --- plat/rpi/boot.s | 33 ++++++++++++++++++++++++--------- 1 file changed, 24 insertions(+), 9 deletions(-) diff --git a/plat/rpi/boot.s b/plat/rpi/boot.s index 9e54d3292..43811a6ad 100644 --- a/plat/rpi/boot.s +++ b/plat/rpi/boot.s @@ -24,13 +24,8 @@ ! the startup sequence mustn't disturb these. begtext: - ! Set up system registers. - - lea gp, begtext - st sp, .returnsp - st lr, .returnlr - - ! Wipe the bss. (I'm a little suprised that __m_a_i_n doesn't do this.) + ! Wipe the bss. This must happen absolutely first, because we need + ! to store the old system registers into it. lea r6, begbss lea r7, endbss @@ -39,15 +34,32 @@ _1: stb r8, (r6) addcmpb.lt r6, #1, r7, _1 + ! Set up system registers. + + lea gp, begtext + st fp, .returnfp + st sp, .returnsp + st lr, .returnlr + ! Set up the new stack and save the kernel parameters to it. - lea sp, .stack + STACKSIZE + lea sp, .stack + STACKSIZE - 6*4 + sub r0, gp ! pointer + st r0, 0 (sp) + sub r1, gp ! pointer + st r1, 4 (sp) + sub r2, gp ! pointer + st r2, 8 (sp) + sub r3, gp ! pointer + st r3, 12 (sp) + ! r4-r5 are not pointers and don't need adjusting - push r0-r5 + st r4, 16 (sp) + st r5, 20 (sp) sub r0, sp, gp st r0, _gpu_parameters @@ -62,10 +74,12 @@ _1: ! Call the language startup code. bl __m_a_i_n + ! Fall through to __exit if this returns. .define __exit __exit: + ld fp, .returnfp ld sp, .returnsp ld lr, .returnlr b lr @@ -88,6 +102,7 @@ __exit: ! We store the stack pointer and return address on entry so that we can ! cleanly exit. +.comm .returnfp, 4 .comm .returnsp, 4 .comm .returnlr, 4 -- 2.34.1