From patchwork Sun Dec 30 18:27:44 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Lukas Auer X-Patchwork-Id: 1019465 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=none (mailfrom) smtp.mailfrom=lists.denx.de (client-ip=81.169.180.215; helo=lists.denx.de; envelope-from=u-boot-bounces@lists.denx.de; receiver=) Authentication-Results: ozlabs.org; dmarc=none (p=none dis=none) header.from=aisec.fraunhofer.de Received: from lists.denx.de (dione.denx.de [81.169.180.215]) by ozlabs.org (Postfix) with ESMTP id 43STY404tFz9s0n for ; Mon, 31 Dec 2018 05:31:19 +1100 (AEDT) Received: by lists.denx.de (Postfix, from userid 105) id AFD15C21E6C; Sun, 30 Dec 2018 18:29:33 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on lists.denx.de X-Spam-Level: X-Spam-Status: No, score=0.0 required=5.0 tests=RCVD_IN_DNSWL_BLOCKED autolearn=unavailable autolearn_force=no version=3.4.0 Received: from lists.denx.de (localhost [IPv6:::1]) by lists.denx.de (Postfix) with ESMTP id 7A8A9C21E56; Sun, 30 Dec 2018 18:29:07 +0000 (UTC) Received: by lists.denx.de (Postfix, from userid 105) id 9BD90C21DFB; Sun, 30 Dec 2018 18:28:32 +0000 (UTC) Received: from mail-edgeDD24.fraunhofer.de (mail-edgeDD24.fraunhofer.de [192.102.167.24]) by lists.denx.de (Postfix) with ESMTPS id DD29CC21E52 for ; Sun, 30 Dec 2018 18:28:31 +0000 (UTC) X-IronPort-Anti-Spam-Filtered: true X-IronPort-Anti-Spam-Result: A2H3AAAO4PJb/xoBYJliGwEBAQEDAQEBBwMBAQGBZYIEgVY5jG+LHZs9DYRsAoNuIjgSAQMBAQIBAQICAmkohT4GMgFGEFE9GgYOBYMhggEBqHyKHAkBh1CEK4FXP4luhQ4Cn28HAoERgQkEjn4LGIlYhyWYFoFdIoFVMxokT4JskFs+ATIBjA4qgiMBAQ X-IPAS-Result: A2H3AAAO4PJb/xoBYJliGwEBAQEDAQEBBwMBAQGBZYIEgVY5jG+LHZs9DYRsAoNuIjgSAQMBAQIBAQICAmkohT4GMgFGEFE9GgYOBYMhggEBqHyKHAkBh1CEK4FXP4luhQ4Cn28HAoERgQkEjn4LGIlYhyWYFoFdIoFVMxokT4JskFs+ATIBjA4qgiMBAQ X-IronPort-AV: E=Sophos;i="5.56,253,1539640800"; d="scan'208";a="22573579" Received: from mail-mtaka26.fraunhofer.de ([153.96.1.26]) by mail-edgeDD24.fraunhofer.de with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 30 Dec 2018 19:28:31 +0100 X-IronPort-Anti-Spam-Filtered: true X-IronPort-Anti-Spam-Result: A0C0AgCO3/Jb/xBhWMBiHAEBAQQBAQcEAQGBZYM5ITmMb6ZaDYRsAoQPOBIBAwEBAgEBAm0ohT0GMgFGEFE9GgYOBYMhggKodoocCQGHUIYCP4luhQ4Cn28HAoERgQkEjn4LGIlYhyWYFoFdIYFVMxokT4JskFs+AzABjA4qgiMBAQ X-IronPort-AV: E=Sophos;i="5.56,253,1539640800"; d="scan'208";a="25375061" Received: from fgdemucivp01ltm.xch.fraunhofer.de (HELO FGDEMUCIMP12EXC.ads.fraunhofer.de) ([192.88.97.16]) by mail-mtaKA26.fraunhofer.de with ESMTP/TLS/AES256-SHA; 30 Dec 2018 19:28:31 +0100 Received: from localhost.de (10.80.233.51) by FGDEMUCIMP12EXC.ads.fraunhofer.de (10.80.232.43) with Microsoft SMTP Server (TLS) id 14.3.408.0; Sun, 30 Dec 2018 19:28:30 +0100 From: Lukas Auer To: Date: Sun, 30 Dec 2018 19:27:44 +0100 Message-ID: <20181230182746.23448-5-lukas.auer@aisec.fraunhofer.de> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20181230182746.23448-1-lukas.auer@aisec.fraunhofer.de> References: <20181230182746.23448-1-lukas.auer@aisec.fraunhofer.de> MIME-Version: 1.0 X-TM-AS-Product-Ver: SMEX-11.0.0.4179-8.200.1013-24324.005 X-TM-AS-Result: No--6.652100-8.000000-31 X-TM-AS-User-Approved-Sender: No X-TM-AS-User-Blocked-Sender: No Cc: Greentime Hu Subject: [U-Boot] [PATCH 4/6] riscv: replace use of callee-saved register in standalone X-BeenThere: u-boot@lists.denx.de X-Mailman-Version: 2.1.18 Precedence: list List-Id: U-Boot discussion List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: u-boot-bounces@lists.denx.de Sender: "U-Boot" Register x19 (s3) is a callee-saved register. It must not be used to load and jump to exported functions without saving it beforehand. Replace it with t0, a temporary and caller-saved register. Change the code comment to reflect this and fix it to correctly list gp as the register with the pointer to global data. Signed-off-by: Lukas Auer Reviewed-by: Bin Meng Tested-by: Bin Meng --- examples/standalone/stubs.c | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-) diff --git a/examples/standalone/stubs.c b/examples/standalone/stubs.c index fadde669fa..f37d209da6 100644 --- a/examples/standalone/stubs.c +++ b/examples/standalone/stubs.c @@ -174,16 +174,16 @@ gd_t *global_data; : : "i"(offsetof(gd_t, jt)), "i"(FO(x)) : "$r16"); #elif defined(CONFIG_RISCV) /* - * t7 holds the pointer to the global_data. gp is call clobbered. + * gp holds the pointer to the global_data. t0 is call clobbered. */ #define EXPORT_FUNC(f, a, x, ...) \ asm volatile ( \ " .globl " #x "\n" \ #x ":\n" \ -" lw x19, %0(gp)\n" \ -" lw x19, %1(x19)\n" \ -" jr x19\n" \ - : : "i"(offsetof(gd_t, jt)), "i"(FO(x)) : "x19"); +" lw t0, %0(gp)\n" \ +" lw t0, %1(t0)\n" \ +" jr t0\n" \ + : : "i"(offsetof(gd_t, jt)), "i"(FO(x)) : "t0"); #elif defined(CONFIG_ARC) /* * r25 holds the pointer to the global_data. r10 is call clobbered.