Can two ADE7953 chips share one MCU SPI port?

Hello,

On my application, there are 4 SPI ports on the MCU. To support 5 metering channels with ADE7953 on each channel, the 4th and 5th ADE7953 chip share one SPI port. I use the chip select pins to select the ADE7953 chips to communicate. Also these two metering IC  share one MCU's external IRQ pin.

With this hardware design, I have the problem to communicate to these ADE7953 chips via SPI port. I can successfully read / write the first, second, and third ADE7953 metering IC without any issue since those have its own SPI port. But when reading any registers on 4th, or 5th ADE7953, always get 0xFF (8-bit) or 0xFFFF(16-bit) values. 

I want to know:

1. Is it the good practice to have multiple ADE7953 chips to share one SPI port as long as making sure to have only one chip select line polling low.

2. If multiple metering ICs can share one SPI port, is there anythings should I pay attention to?

3. Since these two ADE7953 chips share one MCU external IRQ, I need to fully disable all interrupts on one of them. I noticed that on register IRQENA, the default value is 0x100000, bit 20 (Reset) is always enabled, can't be disabled. Will this be the issue? Under what condition will this Reset interrupt be triggered? 

Thank you very much in advance for the help.

Best Regards,

Karen Shi