From mboxrd@z Thu Jan 1 00:00:00 1970 From: Aneesh V Date: Tue, 01 Feb 2011 13:48:17 +0530 Subject: [U-Boot] BSS footprint of FAT very high - SPL issues In-Reply-To: <20110201075521.60484B187@gemini.denx.de> References: <4D4798E2.3050500@ti.com> <20110201075521.60484B187@gemini.denx.de> Message-ID: <4D47C1C9.1020002@ti.com> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: u-boot@lists.denx.de Dear Wolfgang, On Tuesday 01 February 2011 01:25 PM, Wolfgang Denk wrote: > Dear Aneesh V, > > In message<4D4798E2.3050500@ti.com> you wrote: >> >> I had been working on creating an MMC SPL for OMAP4. OMAP boards >> typically support booting from the FAT partition of a removable SD/MMC >> card. So, we need to have FAT support in the SPL. But I am having some >> difficulties in adding FAT support to SPL. >> >> BSS footprint of fat.c is very high. It has three buffers each of size >> 64KB. To workaround this problem I have done something like below(The >> way x-loader works around this problem today). >> CONFIG_SYS_SPL_FAT_BUFFER_BASE is in SDRAM.Is this ok? > > Why would that be necessary? Just put the BSS segment in SDRAM, and > everything is fine, isn't it? SDRAM is initialized by the SPL. So, bss can not be initialized and used until SDRAM initialization is complete. I would prefer to have rest of the bss in internal RAM so that it's available as soon as we enter C code. > >> Also, I was wondering why we need 3 such scratch buffers in this >> implementation. I do not understand this code. But I was wondering if we >> could work with just one 64K buffer? > > I have no idea. I am not familiar with that code either. Probably I will give it a try once I solve some other issues I am facing in getting FAT to work. Best regards, Aneesh