From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from mail.phycore.de ([217.6.246.34] helo=root.phytec.de) by bombadil.infradead.org with esmtp (Exim 4.85_2 #1 (Red Hat Linux)) id 1bs90B-0002v5-15 for barebox@lists.infradead.org; Thu, 06 Oct 2016 13:46:27 +0000 Date: Thu, 6 Oct 2016 15:45:45 +0200 From: Jan Remmet Message-ID: <20161006134545.GA7434@lws-weitzel2@phytec.de> References: MIME-Version: 1.0 In-Reply-To: Content-Disposition: inline List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Reply-To: Jan Remmet Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "barebox" Errors-To: barebox-bounces+u.kleine-koenig=pengutronix.de@lists.infradead.org Subject: Re: am335x: memory configuration To: Yegor Yefremov Cc: barebox On Thu, Oct 06, 2016 at 11:08:07AM +0200, Yegor Yefremov wrote: > I've submitted a patch [1] to support our Baltos systems back in the > May. There was an issue with dynamically detecting RAM size as the > systems can have either 256MB or 512MB modules. > > So far u-boot was able to detect the RAM size dynamically. In order to > do so it uses following code in arch/arm/cpu/armv7/am33xx/emif4.c: > > int dram_init(void) > { > > #ifndef CONFIG_SKIP_LOWLEVEL_INIT > sdram_init(); > #endif > > /* dram_init must store complete ramsize in gd->ram_size */ > gd->ram_size = get_ram_size( > (void *)CONFIG_SYS_SDRAM_BASE, > CONFIG_MAX_RAM_BANK_SIZE); > return 0; > } > > void dram_init_banksize(void) > { > gd->bd->bi_dram[0].start = CONFIG_SYS_SDRAM_BASE; > gd->bd->bi_dram[0].size = gd->ram_size; > } > > This peace of code will be excuted in u-boot.img (not in MLO). > > In Barebox we have get_ram_size(), that provides real RAM size and > am335x_sdram_size(), that returns RAM controller settings. So far DDR > controler will be configured for 512MB regardless of the module. Hence > the return value from am335x_sdram_size() cannot be used for crating > ram0 node. On our am335x boards we use MLOs with individual RAM timings and EMIF config values. So am335x_sdram_size works fine in barebox.bin. Maybe get_ram_size works if the timing settings are equal? Jan > > What were the best way to provide get_ram_size() from lowlevel.c to > board.c, where I would invoke: > arm_add_mem_device("ram0", 0x80000000, sdram_size); > > [1] http://lists.infradead.org/pipermail/barebox/2016-May/027224.html > > Yegor > > _______________________________________________ > barebox mailing list > barebox@lists.infradead.org > http://lists.infradead.org/mailman/listinfo/barebox _______________________________________________ barebox mailing list barebox@lists.infradead.org http://lists.infradead.org/mailman/listinfo/barebox