From mboxrd@z Thu Jan 1 00:00:00 1970 From: York Sun Date: Tue, 11 Mar 2014 08:53:46 -0700 Subject: [U-Boot] [PATCH 1/3] powerpc/p1010rdb: SECURE BOOT- define CONFIG_SYS_RAMBOOT for NAND boot In-Reply-To: <1394495902.6150.10.camel@snotra.buserror.net> References: <1390209926-10115-1-git-send-email-aneesh.bansal@freescale.com> , <1390255477.24905.305.camel@snotra.buserror.net> <680c371d651d49a08b33ddd4d01fb3bd@DM2PR03MB415.namprd03.prod.outlook.com> <20140127142223.DDF2538033A@gemini.denx.de> <7f771c64c5c44208b24e38c75e159f28@DM2PR03MB415.namprd03.prod.outlook.com> <20140128053539.DE87A3801D7@gemini.denx.de> <5316094D.8060504@freescale.com> <8720849b6fdc48aeaf2dcbdfd1905a12@DM2PR03MB415.namprd03.prod.outlook.com> <1394042423.2697.192.camel@snotra.buserror.net> <1394218633.32664.37.camel@snotra.buserror.net> <531A1777.80302@freescale.com> <8b80270d5e2f4dc88e58326f43f00532@DM2PR03MB415.namprd03.prod.outlook.com> <1394495902.6150.10.camel@snotra.buserror.net> Message-ID: <531F318A.6080504@freescale.com> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: u-boot@lists.denx.de On 03/10/2014 04:58 PM, Scott Wood wrote: > On Mon, 2014-03-10 at 04:14 -0500, Bansal Aneesh-B39320 wrote: >>> -----Original Message----- >>> From: Sun York-R58495 >>> Sent: Saturday, March 08, 2014 12:31 AM >>> To: Bansal Aneesh-B39320 >>> Cc: Wood Scott-B07421; Wolfgang Denk; u-boot at lists.denx.de; Gupta >>> Ruchika-R66431 >>> Subject: Re: [U-Boot] [PATCH 1/3] powerpc/p1010rdb: SECURE BOOT- >>> define CONFIG_SYS_RAMBOOT for NAND boot >>> >>> On 03/07/2014 10:57 AM, Scott Wood wrote: >>>> On Thu, 2014-03-06 at 03:24 -0600, Bansal Aneesh-B39320 wrote: >>>>>> -----Original Message----- >>>>>> From: Wood Scott-B07421 >>>>>> Sent: Wednesday, March 05, 2014 11:30 PM >>>>>> To: Bansal Aneesh-B39320 >>>>>> Cc: Sun York-R58495; Wolfgang Denk; u-boot at lists.denx.de; Gupta >>>>>> Ruchika-R66431 >>>>>> Subject: Re: [U-Boot] [PATCH 1/3] powerpc/p1010rdb: SECURE BOOT- >>>>>> define CONFIG_SYS_RAMBOOT for NAND boot >>>>>> >>>>>> On Tue, 2014-03-04 at 23:30 -0600, Bansal Aneesh-B39320 wrote: >>>>>>> Yes, in case of secure boot from NAND, the DRAM is initialized by >>>>>> the >>>>>>> BootROM and complete u-boot image is copied from NAND to DRAM by >>>>>>> the >>>>>> BootROM. >>>>>>> So, it should be called RAMBOOT. >>>>>> >>>>>> DRAM or SRAM? Having ROM initialize DDR is a bit scary. >>>>>> >>>>>> -Scott >>>>>> >>>>> It can be either DDR or SRAM. It is not hardcoded in BootROM to >>> initialize DDR. >>>>> This depends on the config words (CF_WORDS) in the CF_HEADER. >>>>> The Boot ROM code parses the config words and programs the >>> addresses >>>>> with data values accordingly. The user may opt to initialize DDR >>> and >>>>> get the image copied onto DDR or configure CPC as SRAM and get the >>> Image copied onto SRAM. >>>>> On 1010, >>>> >>>> P1010? LS1010? Something else? >>>> >>>>> the CPC size is not big enough to accommodate the U-boot image. >>>>> So, currently the CF_WORDS are for DDR to be initialized and copy >>> the image on DDR. >>>> >>>> Generally if SPD is present, it should be used to init DDR rather >>> than >>>> using hardcoded values. If U-Boot doesn't fit in SRAM, you can use >>>> SPL instead of hardcoded init. >>> >>> I agree with Scott on this point. Using hardcoded values totally skip >>> DDR driver. You don't only lose the flexibility of various speeds, you >>> also skip all workarounds implemented in DDR driver. >>> >>> York >> >> Currently we are following the same approach which was there for SPI >> and SD on P1010 i.e hardcoded initialization of DDR in platforms like >> P1010, 9131/9132 using config words. > > I don't know about 9131/9132, but on P1010RDB we now use SPL to init DDR > when booting from SPI/SD. > > In any case, "we've always done it this way" isn't really a good reason. > We should move to SPL for SD/SPI/NAND. Let's take step by step. I intend to accept the updated patch to get NAND SECURE boot working for this board. Aneesh will submit patches to move to SPL, for SD/SPI/NAND. York