Re: [RFC] AMD polaris MEM_AP_SIZE location (PCI BAR aperture size)

2019-08-28 Thread Petr Cvek
Dne 28. 08. 19 v 15:06 Koenig, Christian napsal(a): >> Yeah but sadly it seems it is possible to only increase the BAR size from >> its currently default 256MB. > > Well the specification allows to change the BAR size from 1MB up to > several TB. The key point is we usually use it to increase th

Re: [RFC] AMD polaris MEM_AP_SIZE location (PCI BAR aperture size)

2019-08-28 Thread Petr Cvek
Dne 28. 08. 19 v 10:31 Christian König napsal(a): > Hi Petr, > > well that is indeed a rather unusual use case. > > I'm not 100% sure how you actually hacked the HD4550 to do what you want to > do, cause this ASIC generation shouldn't support this. I don't remember correctly how exactly I've ma

Re: [RFC] AMD polaris MEM_AP_SIZE location (PCI BAR aperture size)

2019-08-28 Thread Koenig, Christian
> Yeah but sadly it seems it is possible to only increase the BAR size from its > currently default 256MB. Well the specification allows to change the BAR size from 1MB up to several TB. The key point is we usually use it to increase the BAR size, but it is perfectly possible to make it smaller

Re: [RFC] AMD polaris MEM_AP_SIZE location (PCI BAR aperture size)

2019-08-28 Thread Christian König
Hi Petr, well that is indeed a rather unusual use case. I'm not 100% sure how you actually hacked the HD4550 to do what you want to do, cause this ASIC generation shouldn't support this. For a Polaris you can just use the PCIe resizeable BAR extension. For how to use it see the pci_resize_re