From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from phobos.denx.de (phobos.denx.de [85.214.62.61]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 1ECABC433EF for ; Sun, 9 Jan 2022 17:31:49 +0000 (UTC) Received: from h2850616.stratoserver.net (localhost [IPv6:::1]) by phobos.denx.de (Postfix) with ESMTP id 0FD3D81761; Sun, 9 Jan 2022 18:31:39 +0100 (CET) Authentication-Results: phobos.denx.de; dmarc=fail (p=none dis=none) header.from=arm.com Authentication-Results: phobos.denx.de; spf=pass smtp.mailfrom=u-boot-bounces@lists.denx.de Received: by phobos.denx.de (Postfix, from userid 109) id ED9D6832CF; Sun, 9 Jan 2022 18:31:35 +0100 (CET) Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by phobos.denx.de (Postfix) with ESMTP id 368F1830B3 for ; Sun, 9 Jan 2022 18:31:33 +0100 (CET) Authentication-Results: phobos.denx.de; dmarc=pass (p=none dis=none) header.from=arm.com Authentication-Results: phobos.denx.de; spf=pass smtp.mailfrom=andre.przywara@arm.com Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 824C1106F; Sun, 9 Jan 2022 09:31:32 -0800 (PST) Received: from localhost.localdomain (unknown [172.31.20.19]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id C78F33F774; Sun, 9 Jan 2022 09:31:30 -0800 (PST) From: Andre Przywara To: Tom Rini Cc: Simon Glass , Heinrich Schuchardt , Alison Wang , Michael Walle , Nishanth Menon , Priyanka Singh , Peter Hoyes , Marek Vasut , u-boot@lists.denx.de Subject: [PATCH 1/6] cmd: exception: arm64: fix undefined, add faults Date: Sun, 9 Jan 2022 17:30:04 +0000 Message-Id: <20220109173009.25522-2-andre.przywara@arm.com> X-Mailer: git-send-email 2.14.1 In-Reply-To: <20220109173009.25522-1-andre.przywara@arm.com> References: <20220109173009.25522-1-andre.przywara@arm.com> X-BeenThere: u-boot@lists.denx.de X-Mailman-Version: 2.1.38 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" X-Virus-Scanned: clamav-milter 0.103.2 at phobos.denx.de X-Virus-Status: Clean The arm64 version of the exception command was just defining the undefined exception, but actually copied the AArch32 instruction. Replace that with an encoding that is guaranteed to be and stay undefined. Also add instructions to trigger unaligned access faults and a breakpoint. This brings ARM64 on par with ARM(32) for the exception command. Signed-off-by: Andre Przywara --- cmd/arm/exception64.c | 42 ++++++++++++++++++++++++++++++++++++++---- 1 file changed, 38 insertions(+), 4 deletions(-) diff --git a/cmd/arm/exception64.c b/cmd/arm/exception64.c index d5de50a0803..1a9730e6aec 100644 --- a/cmd/arm/exception64.c +++ b/cmd/arm/exception64.c @@ -12,14 +12,46 @@ static int do_undefined(struct cmd_tbl *cmdtp, int flag, int argc, char *const argv[]) { /* - * 0xe7f...f. is undefined in ARM mode - * 0xde.. is undefined in Thumb mode + * Instructions starting with the upper 16 bits all 0 are permanently + * undefined. The lower 16 bits can be used for some kind of immediate. + * --- ARMv8 ARM (ARM DDI 0487G.a C6.2.339: "UDF") */ - asm volatile (".word 0xe7f7defb\n"); + asm volatile (".word 0x00001234\n"); + + return CMD_RET_FAILURE; +} + +static int do_unaligned(struct cmd_tbl *cmdtp, int flag, int argc, + char *const argv[]) +{ + /* + * The load acquire instruction requires the data source to be + * naturally aligned, and will fault even if strict alignment fault + * checking is disabled. + * --- ARMv8 ARM (ARM DDI 0487G.a B2.5.2: "Alignment of data accesses") + */ + asm volatile ( + "mov x1, sp\n\t" + "orr x1, x1, #3\n\t" + "ldar x0, [x1]\n" + ::: "x0", "x1" ); + + return CMD_RET_FAILURE; +} + +static int do_breakpoint(struct cmd_tbl *cmdtp, int flag, int argc, + char *const argv[]) +{ + asm volatile ("brk #123\n"); + return CMD_RET_FAILURE; } static struct cmd_tbl cmd_sub[] = { + U_BOOT_CMD_MKENT(breakpoint, CONFIG_SYS_MAXARGS, 1, do_breakpoint, + "", ""), + U_BOOT_CMD_MKENT(unaligned, CONFIG_SYS_MAXARGS, 1, do_unaligned, + "", ""), U_BOOT_CMD_MKENT(undefined, CONFIG_SYS_MAXARGS, 1, do_undefined, "", ""), }; @@ -27,7 +59,9 @@ static struct cmd_tbl cmd_sub[] = { static char exception_help_text[] = "\n" " The following exceptions are available:\n" - " undefined - undefined instruction\n" + " breakpoint - breakpoint instruction exception\n" + " unaligned - unaligned LDAR data abort\n" + " undefined - undefined instruction exception\n" ; #include -- 2.17.6