BGE_PCI_PCISTATE register before issuing global reset. After
issuing reset, it reads BGE_PCI_PCISTATE register again and
compares the saved register value and current value. It was used to
know whether the global reset operation was completed or not.
Unfortunately, this logic caused several issues on recent BCM5717/
5718/5719 and BCM5720 controllers. It seems APE firmware accesses
some registers while global reset is in progress such that reading
BGE_PCI_PCISTATE register after reset does not yield old pre-reset
state value. This resulted in consuming too much time in global
reset and sometimes it couldn't successfully complete reset.
The BGE_MISCCFG_RESET_CORE_CLOCKS of BGE_MISC_CFG register is
self-clearing bit so driver is able to know the reset completion.
But the core-lock reset will disable indirect/flat/standard access
modes such that driver cannot poll BGE_MISCCFG_RESET_CORE_CLOCKS
bit of BGE_MISC_CFG register. So just wait enough time for
core-clock reset to complete.
Data sheet says driver should wait 100us for PCI/PCI-X devices and
100ms for PCIe devices. I chose 1ms for PCI/PCI-X since this value
was used for many years in bge(4). For PCIe devices, use 100ms as
recommended by data sheet.
bge_chipinit() also cleared BGE_MAC_MODE register which shall clear
firmware configured mode information. I think this will result in
losing ASF/IPMI link in device attachment. Let bge_reset() honor
firmware configured BGE_MAC_MODE register and don't announce driver
is UP in bge_reset(). Firmware should have control over driver until
it's fully initialized by driver.
While I'm here, enable workaround for PCI-X BCM5704 A0 in
bge_reset(). This will prevent internal arbitration logic from
switching to the other DMA engine after a retry cycle.
cc085b3609