Visible to Intel only — GUID: yxs1520804315652
Ixiasoft
Visible to Intel only — GUID: yxs1520804315652
Ixiasoft
3.2.3. Single SDM Flash
In this case, the Quad SPI flash connected to the SDM contains all the data required for configuring and booting the system, including the configuration bitstream, bootloader, and OS files.
The QSPI controller is shared between the SDM and the HPS and only one of these can access the QSPI device at a time. At power-up, the SDM receives access to the QSPI controller. If the HPS needs access to the QSPI flash device, the software running in this (for example, the FSBL or SSBL) must request ownership from the SDM through the HPS-to-SDM mailbox. After the HPS gains ownership of the QSPI controller, it retains ownership until any of the following events occur:
- A power cycle
- A cold reset
- An HPS reboot generated for an RSU event
- An SDM flash storage partition—In this case the SSBL initiates configuration
- In the OS file system—In this case the OS initiates configuration