PXA3xx Boot ROM Reference Manual - Marvell

PXA3xx Processors and Tavor ProcessorBoot ROM Reference ManualThe OEM boot module is described by the image information contained in the image informationarray. It is identified by the "OBMI" image identifier. This is the only required identifier for proper usewith the Trusted Boot ROM. Using the information that describes the OEM boot module, the image isloaded from the flash offset pointed to by FlashEntryAddr to the location pointed to byLoadAddr. The number of bytes loaded is determined by the ImageSize entry.After the image has been loaded to the correct address, the CRC’s ImageSizeToCRC must beverified. The image CRC is calculated based on the ImageSize and LoadAddr entries. Thecalculated CRC is then compared to the CRC stored in the non-trusted image module, in the CRCfield. Upon a successful check, control is transferred to the image at the load address.8.1.3 XIP Flash on Chip Select 0The Trusted Boot ROM supports booting from an XIP device attached to Chip Select 0 of theprocessor static memory controller. There is support for several XIP devices; contact your MarvellApplications Engineer for information about specific devices.The non-trusted image module is expected to be located at offset 0xC000 of the XIP device. ForChip Select 0, the XIP device is memory-mapped to 0x0000_0000, so the non-trusted imagemodule must reside in 0x0000_C000. The Trusted Boot ROM searches for the "TIMH" identifierembedded in the version information of the non-trusted image module. If the structure is found, it isloaded into the internal SRAM of the system. From this point forward, the Trusted Boot ROM usesthe non-trusted image module to load the OEM boot module.The OEM boot module is described by the image information contained in the “IMAGEINFORMATION ARRAY”. It is identified by the "OBMI" image identifier. This is the only requiredidentifier for proper use with the Trusted Boot ROM. Using the information that describes the OEMboot module, the image is loaded from the flash offset pointed to by FlashEntryAddr to thelocation pointed to by LoadAddr. The number of bytes loaded is determined by the ImageSizeentry.After the image has been loaded to the correct address, the CRC must be verified. The image CRCis calculated based on the ImageSize and LoadAddr entries. The calculated CRC is thencompared to the CRC stored in the non-trusted image module, in the CRC field. Upon a successfulcheck, control is transferred to the image at the load address.8.1.4 Samsung OneNAND* FlashThe Trusted Boot ROM supports booting from a x16 OneNAND device attached to Chip Select 2 ofthe processor static memory controller. There is support for large-block devices; contact yourMarvell Applications Engineer for information about specific devices.The non-trusted image module is expected to be located in Block 0 at offset 0x0 of the OneNANDdevice. The OneNAND device is memory-mapped to 0x1000_0000. The Trusted Boot ROM loadsthe first page of Block 0 and searches for the "TIMH" identifier embedded in the version informationof the non-trusted image module. If the structure is found, it is loaded into the internal SRAM of thesystem. From this point forward, the Trusted Boot ROM uses the non-trusted image module to loadthe OEM boot module.The OEM boot module is described by the image information contained in the image informationarray, and is identified by the "OBMI" image identifier. This is the only required identifier for properuse with the Trusted Boot ROM. Using the information that describes the OEM boot module, theimage is loaded from the flash offset pointed to by FlashEntryAddr to the location pointed to byLoadAddr. The number of loaded bytes is determined by the ImageSize entry.After the image has been loaded to the correct address, the CRC must be verified. The image CRCis calculated based on the ImageSize, LoadAddr, and ImageSizeToCRC entries. The calculatedCRC is then compared to the CRC stored in the non-trusted image module, in the CRC field. Upon asuccessful check, control is transferred to the image at the load address.12345678910111213141516171819202122232425262728293031323334353637383940414243444546474849505152535455565758Doc. No. MV-S301208-00 Rev. - PUBLIC RELEASE Copyright © 2010 MarvellPage 82