From: Ayman El-Khashab <ay...@elkhashab.com> This patch is to fix the PCIe on the 460SX CPU. As far as I can tell, the 460SX must be using a different core than the previous 4xx SOCs. The registers aren't the same and it appears DCRs that existed on previous parts don't exist on this one. Perhaps somebody from AMCC can chime in. In any case, the main problem was that the TX and RX weren't enabled so nothing downstream from the RP was ever found. And the check to set "port->link" would never work (as far as I could tell). I could not find any DCRs in this part to indicate when the link was up and there isn't an obvious loopback, so the following call would fail and result in no devices found.
ppc4xx_pciex_wait_on_sdr(port, PESDRn_LOOP, 1 << 28, 1 << 28, 100) It would be better to detect the link status, but I don't see an obvious way to do that from the data sheet. U-boot just skips the link check as well for this part. Ayman El-Khashab (1): ppc4xx: Fix PCIe scanning for the 460SX arch/powerpc/sysdev/ppc4xx_pci.c | 35 +++++++++++++++++++++++++++++++---- 1 files changed, 31 insertions(+), 4 deletions(-) -- 1.7.4.3 _______________________________________________ Linuxppc-dev mailing list Linuxppc-dev@lists.ozlabs.org https://lists.ozlabs.org/listinfo/linuxppc-dev
