From mboxrd@z Thu Jan 1 00:00:00 1970 Delivery-date: Tue, 11 Nov 2025 15:31:29 +0100 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 1vIpP7-000B9w-1j for lore@lore.pengutronix.de; Tue, 11 Nov 2025 15:31:29 +0100 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 1vIpP6-0003a7-SK for lore@pengutronix.de; Tue, 11 Nov 2025 15:31:29 +0100 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: Content-Type:In-Reply-To:From:References:Cc:To:Subject:MIME-Version:Date: Message-ID:Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=HfCiEZAqAC0zbYkF/yPf7fb8HsxF2wQtCY91vMjg9Sw=; b=sIF9v/tqfgl4A6XnUhTQZoZ1YD qqPo+4A1BwAwBnfuoDr+fKBYnmsCyHVA3vz9WwpSj4yfhLnVLYDs2fG123ns+3dKxDck5GE9sh9ex mgDBr+TwljVxwRnW+jfBlGH3UTWtQ+ReGUCgbizicivPAnUcoY4m1Za9Q54+EWg4fpjZVitobcZuG JecGb8/dnathwi/MGze7/oAhNKu35JqcnhwQRfdvlUj68beToWqi0aC4KxJOimMxfbINDJWbslwV/ A2HXGws/Lj3HBwC9yuhlw2ZLi4ZUqg1jTdXdyJ9DZmbDkiEujm2CzWPVd3/7JLLR1rbc0JI1t4gqo 2tHKyltA==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98.2 #2 (Red Hat Linux)) id 1vIpOa-00000007K4D-3l0n; Tue, 11 Nov 2025 14:30:56 +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 1vIpOY-00000007K3n-2tIa for barebox@lists.infradead.org; Tue, 11 Nov 2025 14:30:56 +0000 Received: from ptz.office.stw.pengutronix.de ([2a0a:edc0:0:900:1d::77] helo=[127.0.0.1]) by metis.whiteo.stw.pengutronix.de with esmtp (Exim 4.92) (envelope-from ) id 1vIpOV-0003Sl-0n; Tue, 11 Nov 2025 15:30:51 +0100 Message-ID: Date: Tue, 11 Nov 2025 15:30:49 +0100 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird To: Sascha Hauer , Marco Felsch Cc: BAREBOX References: <20251110-v2025-09-0-topic-optee-of-handling-v1-0-8f0625ac5471@pengutronix.de> <20251110-v2025-09-0-topic-optee-of-handling-v1-10-8f0625ac5471@pengutronix.de> Content-Language: en-US, de-DE, de-BE From: Ahmad Fatoum In-Reply-To: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20251111_063054_741395_90A2DACE X-CRM114-Status: GOOD ( 23.50 ) 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=-4.1 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: Re: [PATCH 10/23] ARM: i.MX: scratch: add FDT support 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) Hi, On 11/11/25 3:14 PM, Sascha Hauer wrote: > On Mon, Nov 10, 2025 at 09:34:50PM +0100, Marco Felsch wrote: >> Add support to store a FDT within the scratch area. The user needs to >> query the location and size via imx_scratch_get_fdt() which can be used >> afterwards to write the actual FDT into it. >> >> Signed-off-by: Marco Felsch >> --- >> arch/arm/mach-imx/scratch.c | 16 ++++++++++++++++ >> common/Kconfig | 14 ++++++++++++++ >> include/mach/imx/scratch.h | 2 ++ >> 3 files changed, 32 insertions(+) >> >> diff --git a/arch/arm/mach-imx/scratch.c b/arch/arm/mach-imx/scratch.c >> index e4e2d25969f061c9fcdfd7c3d87701b715eb2805..9c0f1c09c4e0b863d8c95888db7cf0518f698d53 100644 >> --- a/arch/arm/mach-imx/scratch.c >> +++ b/arch/arm/mach-imx/scratch.c >> @@ -16,7 +16,10 @@ struct imx_scratch_space { >> u32 bootrom_log[128]; >> u32 reserved[128]; /* reserve for bootrom log */ >> struct optee_header optee_hdr; >> + /* FDT needs an 8 byte alignment */ >> + u8 fdt[CONFIG_SCRATCH_FDT_SIZE] __aligned(8); >> }; >> +static_assert(sizeof(struct imx_scratch_space) <= CONFIG_SCRATCH_SIZE); >> >> static struct imx_scratch_space *scratch; >> >> @@ -92,3 +95,16 @@ const struct optee_header *imx_scratch_get_optee_hdr(void) >> >> return &scratch->optee_hdr; >> } >> + >> +void imx_scratch_get_fdt(void **fdt, unsigned int *fdt_sz) >> +{ >> + if (!scratch) { >> + if (IN_PBL) >> + return; >> + else >> + scratch = (void *)arm_mem_scratch_get(); >> + } >> + >> + *fdt = scratch->fdt; >> + *fdt_sz = sizeof(scratch->fdt); >> +} >> diff --git a/common/Kconfig b/common/Kconfig >> index eb2fb1da1e0919b6e7d5e868c48ad2e195cd8aa8..3f394416c3c376d1cf842472803a47462bb012ed 100644 >> --- a/common/Kconfig >> +++ b/common/Kconfig >> @@ -302,8 +302,22 @@ config MALLOC_SIZE >> config SCRATCH_SIZE >> hex >> default 0x8000 >> + default 0x48000 if PBL_EARLY_FDT_LOAD Easy to misconfigure. How about an additional: range 0x48000 if PBL_EARLY_FDT_LOAD >> prompt "Scratch size" > > Do I get this right that the scratch space now includes the space for > the early FDT? If yes then this can lead to inconsistencies when the > scratch space is to small. Why not add an extra space? I would prefer we do not complicate the "endmem" layout more than we have currently. What I think we want in future is an API to allocate from the scratch mem a handoff block and there would be no hardcoded offsets and struct imx_scratch_space could go away. To save handoff when switching from PBL to proper, we would then also allocate to the scratch space. This will probably happen separately, so I am in favor of not creating a new section that's removed afterwards. Cheers, Ahmad > > Sascha > -- Pengutronix e.K. | | Steuerwalder Str. 21 | http://www.pengutronix.de/ | 31137 Hildesheim, Germany | Phone: +49-5121-206917-0 | Amtsgericht Hildesheim, HRA 2686 | Fax: +49-5121-206917-5555 |