From patchwork Wed Jul 8 01:25:42 2015 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sam Mendoza-Jonas X-Patchwork-Id: 492661 Return-Path: X-Original-To: patchwork-incoming@ozlabs.org Delivered-To: patchwork-incoming@ozlabs.org Received: from lists.ozlabs.org (lists.ozlabs.org [103.22.144.68]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id C0FAC140B0E for ; Wed, 8 Jul 2015 11:27:35 +1000 (AEST) Received: from lists.ozlabs.org (lists.ozlabs.org [IPv6:2401:3900:2:1::3]) by lists.ozlabs.org (Postfix) with ESMTP id A64071A1D0F for ; Wed, 8 Jul 2015 11:27:35 +1000 (AEST) 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 BA2DE1A196E for ; Wed, 8 Jul 2015 11:26:30 +1000 (AEST) Received: by ozlabs.org (Postfix) id 8B1F8140D24; Wed, 8 Jul 2015 11:26:30 +1000 (AEST) Delivered-To: linuxppc-dev@ozlabs.org Received: from e23smtp01.au.ibm.com (e23smtp01.au.ibm.com [202.81.31.143]) (using TLSv1 with cipher CAMELLIA256-SHA (256/256 bits)) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id 59E77140B0E for ; Wed, 8 Jul 2015 11:26:30 +1000 (AEST) Received: from /spool/local by e23smtp01.au.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! 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Violators will be prosecuted; Wed, 8 Jul 2015 11:26:26 +1000 X-Helo: d23dlp03.au.ibm.com X-MailFrom: sam.mj@au1.ibm.com X-RcptTo: linuxppc-dev@ozlabs.org Received: from d23relay09.au.ibm.com (d23relay09.au.ibm.com [9.185.63.181]) by d23dlp03.au.ibm.com (Postfix) with ESMTP id 41EFB3578048 for ; Wed, 8 Jul 2015 11:26:24 +1000 (EST) Received: from d23av02.au.ibm.com (d23av02.au.ibm.com [9.190.235.138]) by d23relay09.au.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id t681QG0h49873058 for ; Wed, 8 Jul 2015 11:26:24 +1000 Received: from d23av02.au.ibm.com (localhost [127.0.0.1]) by d23av02.au.ibm.com (8.14.4/8.14.4/NCO v10.0 AVout) with ESMTP id t681PpmL020379 for ; Wed, 8 Jul 2015 11:25:52 +1000 Received: from ozlabs.au.ibm.com (ozlabs.au.ibm.com [9.192.253.14]) by d23av02.au.ibm.com (8.14.4/8.14.4/NCO v10.0 AVin) with ESMTP id t681PpSB019834; Wed, 8 Jul 2015 11:25:51 +1000 Received: from skellige.ozlabs.ibm.com (unknown [9.192.254.114]) (using TLSv1.2 with cipher AES128-SHA256 (128/128 bits)) (No client certificate requested) by ozlabs.au.ibm.com (Postfix) with ESMTPSA id A4368A01A1; Wed, 8 Jul 2015 11:25:27 +1000 (AEST) From: Samuel Mendoza-Jonas To: anton@samba.org Subject: [kexec-lite PATCH] trampoline: Reset primary cpu endian to big-endian Date: Wed, 8 Jul 2015 11:25:42 +1000 Message-Id: <1436318742-13490-1-git-send-email-sam.mj@au1.ibm.com> X-Mailer: git-send-email 2.4.5 X-TM-AS-MML: disable X-Content-Scanned: Fidelis XPS MAILER x-cbid: 15070801-1618-0000-0000-000002590DB7 X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.20 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: linuxppc-dev@ozlabs.org, Samuel Mendoza-Jonas MIME-Version: 1.0 Errors-To: linuxppc-dev-bounces+patchwork-incoming=ozlabs.org@lists.ozlabs.org Sender: "Linuxppc-dev" Older big-endian ppc64 kernels don't include the FIXUP_ENDIAN check, meaning if we kexec from a little-endian kernel the target kernel will fail to boot. Returning to big-endian before we enter the target kernel ensures that the target kernel can boot whether or not it includes FIXUP_ENDIAN. Signed-off-by: Samuel Mendoza-Jonas --- kexec_trampoline.S | 9 ++++++++- kexec_trampoline.h | 17 +++++++++++++++-- 2 files changed, 23 insertions(+), 3 deletions(-) diff --git a/kexec_trampoline.S b/kexec_trampoline.S index a3eb314..29537ab 100644 --- a/kexec_trampoline.S +++ b/kexec_trampoline.S @@ -41,6 +41,8 @@ #define r7 7 #define r8 8 #define r9 9 +#define r10 10 +#define r11 11 #ifdef __powerpc64__ #define LOAD ld @@ -50,8 +52,10 @@ #if defined(__LITTLE_ENDIAN__) #define STWX_BE stwbrx +#define BCTR .long 0x2004804e #elif defined(__BIG_ENDIAN__) #define STWX_BE stwx +#define BCTR bctr #else #error no endianness defined! #endif @@ -89,7 +93,10 @@ start: li r5,0 mtctr r4 - bctr + + RESET_ENDIAN + + BCTR . = KERNEL_ADDR_OFFSET kernel_addr: diff --git a/kexec_trampoline.h b/kexec_trampoline.h index 6485c88..909953b 100644 --- a/kexec_trampoline.h +++ b/kexec_trampoline.h @@ -27,7 +27,20 @@ /* Fixed offset in device tree for storing the physical ID of the boot CPU */ #define DT_CPU_OFFSET 28 -#ifndef __ASSEMBLY__ +#ifdef __ASSEMBLY__ +#define RESET_ENDIAN \ + mfmsr r9; \ + clrldi. r10,r9,63; \ + beq $+36; /* Already big-endian */ \ + bcl 20,31,$+4; \ + mflr r10; \ + addi r10,r10,28; \ + mfmsr r11; \ + xori r11,r11,1; \ + mtsrr0 r10; \ + mtsrr1 r11; \ + rfid; +#else extern char __trampoline_start[]; extern char __trampoline_end[]; @@ -48,6 +61,6 @@ static inline void trampoline_set_device_tree(void *p, unsigned long addr) *v = addr; } -#endif +#endif /* !__ASSEMBLY__ */ #endif