From mboxrd@z Thu Jan 1 00:00:00 1970 From: =?utf-8?Q?Beno=C3=AEt_Th=C3=A9baudeau?= Date: Tue, 21 Aug 2012 00:47:45 +0200 (CEST) Subject: [U-Boot] ROM_SI_REV on MX5 In-Reply-To: Message-ID: <2030643206.2614282.1345502865861.JavaMail.root@advansee.com> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: u-boot@lists.denx.de Hi Matt, > >> Can anyone tell me where this offset is in relation to, or what > >> it's > >> actually meant to be? > >> > >> Some parts of U-Boot read it out but I can't figure any part of > >> the > >> docs that refers to this magic 0x48 offset or what it could be (or > >> what it should be when you read it out)? > > > > See "Figure 9-1. Internal ROM and RAM Memory Map" in the i.MX51 RM. > > This is the > > only reference to it that I find in the RM. All the details > > probably come from > > FSL's code. I think that it's close to IIM.SREV, if not the same. > > It's supposed > > to be a ROM version, but it's used like a silicon/tapeout revision. > > We've got several boards that seem to randomly change ROM_SI_REV > contents on random boots (one of them went from rev2.5 to rev2.0 to > rev3.0 and back again), and looking at the details on a TO3.. > IIM.SILICON_REV reports 0x10 for the revision of a TO3, so that's an > identifier for that I think, otherwise it's 0x00. For silicon > revision > 2.0, 2.5 I can't confirm this data at location 0x48 of the memory map > though. For TO3 the copyright string for the i.MX boot ROM has > basically gone (it's not random data at 0x00000000 though, it's > exactly the same every time..) How do you read ROM_SI_REV? With the md command? With the silicon revision printed by U-Boot on startup? When it changes, is it always after the same reset cause (POR, WDT, etc.)? > Looking at the GPIO registers I can't even confirm that the > directions > we're setting in U-Boot are correct, although U-Boot is doing what we > consider to be "the right thing".. the board revisions come out fine > from PCBID. What do you mean by "can't"? What do you get if you read the GPIO DIR registers? Best regards, Beno?t