From patchwork Tue Feb 10 12:15:10 2015 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jeremy Kerr X-Patchwork-Id: 438351 X-Patchwork-Delegate: michael@ellerman.id.au Return-Path: X-Original-To: patchwork-incoming@ozlabs.org Delivered-To: patchwork-incoming@ozlabs.org Received: from lists.ozlabs.org (lists.ozlabs.org [IPv6:2401:3900:2:1::3]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id CFE051401F0 for ; Tue, 10 Feb 2015 23:17:53 +1100 (AEDT) Received: from ozlabs.org (ozlabs.org [103.22.144.67]) by lists.ozlabs.org (Postfix) with ESMTP id AF6181A12E7 for ; Tue, 10 Feb 2015 23:17:53 +1100 (AEDT) X-Original-To: linuxppc-dev@lists.ozlabs.org Delivered-To: linuxppc-dev@lists.ozlabs.org Received: from ozlabs.org (ozlabs.org [IPv6:2401:3900:2:1::2]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 1BDAF1A020A for ; Tue, 10 Feb 2015 23:15:16 +1100 (AEDT) Received: by ozlabs.org (Postfix, from userid 1023) id 0369F1402B8; Tue, 10 Feb 2015 23:15:15 +1100 (AEDT) MIME-Version: 1.0 Subject: [PATCH 4/4] powerpc/boot: don't clobber r6 and r7 in epapr boot Message-Id: <1423570510.219346.759068385066.4.gpush@pablo> In-Reply-To: <1423570510.218330.214724142596.1.gpush@pablo> To: linuxppc-dev@lists.ozlabs.org From: Jeremy Kerr Date: Tue, 10 Feb 2015 20:15:10 +0800 X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.18 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: linuxppc-dev-bounces+patchwork-incoming=ozlabs.org@lists.ozlabs.org Sender: "Linuxppc-dev" We use r6 and r7 for epapr boot, but the current pre-C init will clobber both of these. This change does a simple replacement, of r6 -> r12 and r7 -> r13, so that we hit platform init with these registers intact. Signed-off-by: Jeremy Kerr --- arch/powerpc/boot/crt0.S | 24 ++++++++++++------------ 1 file changed, 12 insertions(+), 12 deletions(-) diff --git a/arch/powerpc/boot/crt0.S b/arch/powerpc/boot/crt0.S index bf8eeee..7e50211 100644 --- a/arch/powerpc/boot/crt0.S +++ b/arch/powerpc/boot/crt0.S @@ -155,29 +155,29 @@ p_base: mflr r10 /* r10 now points to runtime addr of p_base */ ld r9,(p_rela-p_base)(r10) add r9,r9,r10 - li r7,0 + li r13,0 li r8,0 -9: ld r6,0(r11) /* get tag */ - cmpdi r6,0 +9: ld r12,0(r11) /* get tag */ + cmpdi r12,0 beq 12f /* end of list */ - cmpdi r6,RELA + cmpdi r12,RELA bne 10f - ld r7,8(r11) /* get RELA pointer in r7 */ + ld r13,8(r11) /* get RELA pointer in r13 */ b 11f -10: addis r6,r6,(-RELACOUNT)@ha - cmpdi r6,RELACOUNT@l +10: addis r12,r12,(-RELACOUNT)@ha + cmpdi r12,RELACOUNT@l bne 11f ld r8,8(r11) /* get RELACOUNT value in r8 */ 11: addi r11,r11,16 b 9b 12: - cmpdi r7,0 /* check we have both RELA and RELACOUNT */ + cmpdi r13,0 /* check we have both RELA and RELACOUNT */ cmpdi cr1,r8,0 beq 3f beq cr1,3f /* Calcuate the runtime offset. */ - subf r7,r7,r9 + subf r13,r13,r9 /* Run through the list of relocations and process the * R_PPC64_RELATIVE ones. */ @@ -185,10 +185,10 @@ p_base: mflr r10 /* r10 now points to runtime addr of p_base */ 13: ld r0,8(r9) /* ELF64_R_TYPE(reloc->r_info) */ cmpdi r0,22 /* R_PPC64_RELATIVE */ bne 3f - ld r6,0(r9) /* reloc->r_offset */ + ld r12,0(r9) /* reloc->r_offset */ ld r0,16(r9) /* reloc->r_addend */ - add r0,r0,r7 - stdx r0,r7,r6 + add r0,r0,r13 + stdx r0,r13,r12 addi r9,r9,24 bdnz 13b