Please refer to the tables in 5.6.2 FPGA Programming Time in the PolarFire FPGA Datasheet.

Table 5-68. SPI Initiator and Auto-Update Programming Time (IAP)
Table 5-69. SPI Target Programming Time
Table 5-70. JTAG Programming Time

Please understand that the SPI Initiator is the SPI Master and the SPI Target is the SPI Slave.

The PolarFire FPGA Datasheet can be found by opening the Data Sheets tab in the PolarFire Documentation.
https://www.microchip.com/en-us/products/fpgas-and-plds/fpgas/polarfire-fpgas/polarfire-mid-range-fpgas#Documentation