I am using the P1013 and attempting to enable the three PCI Express controllers. The DEVDISR register shows that PCIe1, PCIe2 and PCIe3 are all disabled following power-on / reset. When I attempt to clear any of these bits in the DEVDISR, there is no effect on the register. According to the Reference Manual, these bits' reset values depend on POR configuration signals at reset.
By reading PORDEVSR, I see that IO_SEL_SRDS is configured with 0b11000, which should be SerDes1: PCIe1 (x2), PCIe2 (x2), SerDes2: PCIe3 (x2).
By reading PORBMSR, I see that Host-Agent configuration (HA field) is set to 0b100, which should be Agent on PCIe1, PCIe2 and Host on PCIe3.
We are booting using the I2C for a Boot Sequencer, which attempts to set the DEVDISR register so that PCIe1, PCIe2 and PCIe3 are not disabled.
However I cannot get the corresponding bits in DEVDISR to clear. Also, the CCSR Register ranges for PCIe controllers and the SerDes controllers all read back as all zeroes.
Does anyone know what I might be doing wrong?