OMAP-L138: Serial Boot Flash size for OMAP-L138

ASB

Intellectual 355 points

Part Number: OMAP-L138

Hi for custom board what is the largest serial flash is supported? I will be using SPI1 for OMAP L138 bootup.

over 5 years ago

0 Mark Mckeown over 5 years ago

TI__Mastermind 29180 points

SPI Flash memories uses a 24-bit address to address each data byte.

So the largest serial flash possible is 128Mb (2^24 * 8). This range is supported by the OMAP-L138.

You must use SPI1_CS0 (or SPI0_CS0) to boot. The bootloader boots from address 0.

Whenever you boot from SPI Flash the 24-bit address must be used. Whenever you boot from SPI EEPROM a 16-bit address must be used.

Hope this helps,
Mark

0 ASB over 5 years ago in reply to Mark Mckeown

Intellectual 355 points

Can larger densities of SPI NOR flash be supported on OMAP L-138 SPI bus for other than bootloader for user data storage?

0 Mark Mckeown over 5 years ago in reply to ASB

TI__Mastermind 29180 points

Yes. Just keep in mind that the bootloader starts reading from address 0x0 and its size depends on the boot image.

You may use the rest of the SPI NOR for data storage, etc.

Regards,
Mark

0 ASB over 5 years ago in reply to Mark Mckeown

Intellectual 355 points

OK let me see if I understood this correctly, so If I use 256Mbit of serial flash with OMAP connected to SPI1 (SPI1_CS0), the bootloader should be in lower 16M Byte space starting from address 0x0? The remaining space ( 16MBytes )can be used for user data storage?

0 Mark Mckeown over 5 years ago in reply to ASB

TI__Mastermind 29180 points

You got it. What you stated is accurate.
The total size of the boot image should be (much) less than 16MB, but it depends on the program. You can try creating a boot image with the AIS tool (and program it into the SPI flash) to get an idea of how much space it requires. Refer to the SPRAB41E appnote. www.ti.com/.../sprab41e.pdf

Regards,
Mark

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OMAP-L138: Serial Boot Flash size for OMAP-L138