From mboxrd@z Thu Jan 1 00:00:00 1970 Delivery-date: Fri, 24 Oct 2025 18:42:22 +0200 Received: from metis.whiteo.stw.pengutronix.de ([2a0a:edc0:2:b01:1d::104]) by lore.white.stw.pengutronix.de with esmtps (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.96) (envelope-from ) id 1vCKru-00BNGg-31 for lore@lore.pengutronix.de; Fri, 24 Oct 2025 18:42:22 +0200 Received: from bombadil.infradead.org ([2607:7c80:54:3::133]) by metis.whiteo.stw.pengutronix.de with esmtps (TLS1.3:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1vCKru-0002VV-95 for lore@pengutronix.de; Fri, 24 Oct 2025 18:42:22 +0200 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Content-Transfer-Encoding: MIME-Version:Message-ID:Date:Subject:To:From:Reply-To:Cc:Content-Type: Content-ID:Content-Description:Resent-Date:Resent-From:Resent-Sender: Resent-To:Resent-Cc:Resent-Message-ID:In-Reply-To:References:List-Owner; bh=ecnK3M9Onxt7AWDRnGPuuMhX96jkMz4pEImj9TAyyng=; b=zdcmLkIj9Li2yB9y2kRMYcjRgf zxDccme2l9UPRTQKVFrBUrV01ZWH2bUGQ2rDQ2tHYoaxEVqTVivq+dmqn8k0IJx3eNvdXL333oiUZ XhMo+G8845jhL8XX+/0Yl8WRRr+mbGh1DChm9foidGNt5YZoLIgtI/jJQ7XOrSJtOW6hIqBeDC7jn qVxYSJlOjTphypKUAmbm+QjIBzutUxpWGyppwUl21Eqf0QeHdIzvU99hjNMJ99A0sfAnLOSNqEJ// OwsgEtbQc3y+90uPChhiO7Sjm97n61WT3bJRU9FHo9WUTE+2DVG39TYhT/0hI+R147iPQt/f7ODXV B2AepVYg==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98.2 #2 (Red Hat Linux)) id 1vCKrF-0000000A0E3-3728; Fri, 24 Oct 2025 16:41:41 +0000 Received: from metis.whiteo.stw.pengutronix.de ([2a0a:edc0:2:b01:1d::104]) by bombadil.infradead.org with esmtps (Exim 4.98.2 #2 (Red Hat Linux)) id 1vCKrD-0000000A0Df-006v for barebox@lists.infradead.org; Fri, 24 Oct 2025 16:41:40 +0000 Received: from dude02.red.stw.pengutronix.de ([2a0a:edc0:0:1101:1d::28]) by metis.whiteo.stw.pengutronix.de with esmtp (Exim 4.92) (envelope-from ) id 1vCKr9-0002Np-6j for barebox@lists.infradead.org; Fri, 24 Oct 2025 18:41:35 +0200 From: Marco Felsch To: barebox@lists.infradead.org Date: Fri, 24 Oct 2025 18:41:27 +0200 Message-ID: <20251024164133.1937633-1-m.felsch@pengutronix.de> X-Mailer: git-send-email 2.47.3 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20251024_094139_060134_F554CA81 X-CRM114-Status: UNSURE ( 8.66 ) X-CRM114-Notice: Please train this message. X-BeenThere: barebox@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "barebox" X-SA-Exim-Connect-IP: 2607:7c80:54:3::133 X-SA-Exim-Mail-From: barebox-bounces+lore=pengutronix.de@lists.infradead.org X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on metis.whiteo.stw.pengutronix.de X-Spam-Level: X-Spam-Status: No, score=-4.0 required=4.0 tests=AWL,BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_NONE autolearn=unavailable autolearn_force=no version=3.4.2 Subject: [PATCH] ARM: atf: document BL32 FDT argument X-SA-Exim-Version: 4.2.1 (built Wed, 08 May 2019 21:11:16 +0000) X-SA-Exim-Scanned: Yes (on metis.whiteo.stw.pengutronix.de) Document the BL32 arg3 FDT passing to avoid confusions since OP-TEE expects the FDT via arg2 and not arg3. That the TF-A is shifting the arguments is not very obvious. Signed-off-by: Marco Felsch --- arch/arm/cpu/atf.c | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/arch/arm/cpu/atf.c b/arch/arm/cpu/atf.c index d01e20508c7a..7abe43a2703e 100644 --- a/arch/arm/cpu/atf.c +++ b/arch/arm/cpu/atf.c @@ -158,6 +158,14 @@ struct bl2_to_bl31_params_mem_v2 *bl2_plat_get_bl31_params_v2(uintptr_t bl32_ent p.bl33_ep_info.args.arg0 = 0xffff & read_mpidr(); p.bl33_ep_info.pc = bl33_entry; + /* + * The FDT address is passed via arg3 to the BL32. The BL31 which is in + * charge to start the BL32, adapts this information and passes the FDT + * via arg2 to the BL32 in case of OP-TEE since OP-TEE expects the FDT + * within arg2. The reason for this behaviour is the TF-A legacy code + * path which uses arg0 to specify the SPSR (AARCH32, AARCH64) state. + * Therefore all OP-TEE call arguments are shifted by one. + */ p.bl32_ep_info.args.arg3 = fdt_addr; p.bl32_ep_info.pc = bl32_entry; -- 2.47.3