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Honored Contributor
Honored ContributorHelp: Windows didn't assign Bar0 to PCie (address mapping is not correct)
Dear all, We changed the Altera Cyclone PCIe DDR2 reference design to our needs. However, it doesn't work. The address mapping is not correct, it doesn't agree to address assignments in Qsys. ...
Altera_ForumHonored Contributor
Honored Contributor --- Quote Start --- can the bar region be as large as 256 MB or more? --- Quote End --- The PCIe spec will not stop you, but your particular hardware might. My EliteBook will not boot with a BAR of 256MB. --- Quote Start --- We use "system"-> "assign base address" menu, the DDR now is mapped to 0x0000_0000 to 0x0fff_ffff, the on-chip memory now is mapped to 0x1000_0000 to 0x1003_ffff. But it still doesn't work. Bar0 still does not appear. --- Quote End --- Because you did not change the BAR size by doing this. Look at the report on the Qsys GUI. Look at the synthesis report. Look at this document here: http://www.alteraforum.com/forum/showthread.php?t=35678 It has some comments. To try and isolate this problem, start with just the on-chip RAM in the BAR at a base address of zero. You can use the "Address Map" tab to re-assign the addresses. Once you can confirm that you can boot windows, you can increase the size of the BAR (the offset of the on-chip RAM) until it breaks. Then you will know the limits for your particular hardware setup. Cheers, Dave
