Network fails to init on Garrison

[sammj]

On newish kernels the tg3 device on Garrison fails to init:

Aug  7 06:21:17 skiroot user.info kernel: [    3.878052] tg3.c:v3.137 (May 11, 2014)
Aug  7 06:21:17 skiroot user.warn kernel: [    3.878081] tg3 0009:07:00.0: can't ioremap BAR 0: [??? 0x00000000 flags 0x0]
Aug  7 06:21:17 skiroot user.err kernel: [    3.878083] tg3 0009:07:00.0: Cannot map device registers, aborting
Aug  7 06:21:17 skiroot user.warn kernel: [    3.878311] tg3: probe of 0009:07:00.0 failed with error -12
Aug  7 06:21:17 skiroot user.warn kernel: [    3.878336] tg3 0009:07:00.1: can't ioremap BAR 0: [??? 0x00000000 flags 0x0]
Aug  7 06:21:17 skiroot user.err kernel: [    3.878338] tg3 0009:07:00.1: Cannot map device registers, aborting
Aug  7 06:21:17 skiroot user.warn kernel: [    3.878419] tg3: probe of 0009:07:00.1 failed with error -12

This occurs in both Petitboot and the host OS:

# ./pflash -r /dev/stdout -P VERSION
Reading to "/dev/stdout" from 0x01ff7000..0x01ff8000 !
[                                                  ] 0%
open-power-garrison-v1.18-32-g21dbb70
	buildroot-2017.05-163-g8035745
	skiboot-v5.7-24-g81c0e076374e
	hostboot-695bd89
	linux-4.12.3-openpower1-pa9bb7b5
	petitboot-v1.5.1-pcc28100
	machine-xml-19a5164
	occ-28f2cec
	hostboot-binaries-883d218
	capp-ucode-9c73e9f
[==================================================] 100%

kernel_garrison1.txt