Hello, The goal of these changes is to refresh the QEMU ref405ep machine and enable boot from a Linux kernel without relying on a U-Boot firmware. The reason for doing so is that we are unable to find a "ppc405_rom.bin" firmware image or a flash image for the 405EP machines.
Thomas fought is way through on a v2015.10 U-Boot and taihu defconfig and provided a compatible image available here : https://gitlab.com/huth/u-boot/-/tree/taihu/ With this image, QEMU reaches the U-Boot prompt (with a simple workaround in the SDRAM). On the Linux side, the only available 405EP CPU board is the one for the ESTeem 195E (PPC405EP) SBC (hotfoot). It was added in 2009. The board information structure in Linux, in U-Boot and in QEMU are not in sync and the hotfoot board also adds its own flavor because the FW was an ancient U-Boot without dual ethernet support [1]. For this kernel to be loaded by the U-Boot image provided by Thomas, we either need to modify U-Boot or Linux. The same question arise for QEMU, see the last patch of this series which is controversial. Please advise ! Thanks, C. [1] https://lists.ozlabs.org/pipermail/linuxppc-dev/2009-July/074487.html Cédric Le Goater (14): ppc/ppc405: Change kernel load address ppc: Add trace-events for DCR accesses ppc/ppc405: Convert printfs to trace-events ppc/ppc405: Drop flag parameter in ppc405_set_bootinfo() ppc/ppc405: Change ppc405ep_init() return value ppc/ppc405: Add some address space definitions ppc/ppc405: Remove flash support ppc/ppc405: Rework FW load ppc/ppc405: Introduce ppc405_set_default_bootinfo() ppc/ppc405: Fix boot from kernel ppc/ppc405: Change default PLL values at reset ppc/ppc405: Fix bi_pci_enetaddr2 field in U-Boot board information ppc/ppc405: Add update of bi_procfreq field ppc/ppc405: Update U-Boot board information for hotfoot Thomas Huth (1): ppc: Mark the 'taihu' machine as deprecated docs/about/deprecated.rst | 9 ++ hw/ppc/ppc405.h | 14 +- hw/ppc/ppc.c | 2 + hw/ppc/ppc405_boards.c | 245 ++++++++++++++++++---------------- hw/ppc/ppc405_uc.c | 270 +++++++++++++++++++++----------------- hw/ppc/trace-events | 23 ++++ 6 files changed, 327 insertions(+), 236 deletions(-) -- 2.31.1