From mboxrd@z Thu Jan 1 00:00:00 1970 From: Detlev Zundel Date: Thu, 20 Aug 2009 13:18:07 +0200 Subject: [U-Boot] Porting to Broadcom BCM7038 (Hermes board) In-Reply-To: <574bb010908200247h7c045417n1877f636e6dbebff@mail.gmail.com> (Peter Belm's message of "Thu, 20 Aug 2009 10:47:55 +0100") References: <574bb010908180632o3b13a11cwa967ce37ff4b404a@mail.gmail.com> <20090819191933.5053D833DBD2@gemini.denx.de> <574bb010908200229m7da12930s39f7bc40a2384f1d@mail.gmail.com> <20090820094159.BDB3B833DBD2@gemini.denx.de> <574bb010908200247h7c045417n1877f636e6dbebff@mail.gmail.com> Message-ID: List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: u-boot@lists.denx.de Hi Peter, > All the tasks you mention here are performed by U-Boot. U-Boot _is_ > the boot loader. > > Right, I'm just having trouble getting to grips with the code flow, the start.S > in the CPU is the initial entry point, at what point does that hand over to > U-Boot? Any chance you could give me a brief overview of the code flow? In > particular where the code I need to write fits in with the boot process, i.e. > where I need to interface with U-Boot. > > Once I've got a better idea of how U-Boot boots, I should be able to get > started at least. Be sure to read the section "Implementation Internals" in the README. Other than that, simply trace the flow (on a piece of paper) for a comparable board, e.g. the "purple" board which seems to be pretty close to what you have. Another hint is that functions in U-Boot ending with _f are run from flash, wherease functions ending in _r run already relocated from RAM. I hope this gets you started. Cheers Detlev -- It's like manually inflatable airbags -- people will never think to use it in time to actually get any help from it. -- Miles Bader in <20030607122005.GA1086@gnu.org> -- DENX Software Engineering GmbH, MD: Wolfgang Denk & Detlev Zundel HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany Phone: (+49)-8142-66989-40 Fax: (+49)-8142-66989-80 Email: dzu at denx.de