pci-mvebu driver on km_kirkwood
From: Thomas Petazzoni <hidden>
Date: 2014-02-21 15:11:08
Also in:
linux-pci
Dear Arnd Bergmann, On Fri, 21 Feb 2014 16:05:16 +0100, Arnd Bergmann wrote:
quoted
*) I don't know if the algorithm to split the BAR into multiple windows is going to be trivial.The easiest solution would be to special case 'size is between 128MB+1 and 192MB' if that turns out to be the most interesting case. It's easy enough to make the second window smaller than 64MB if we want. If we want things to be a little fancier, we could use: switch (size) { case (SZ_32M+1) ... (SZ_32M+SZ_16M): size2 = size - SZ_32M; size -= SZ_32M; break; case (SZ_64M+1) ... (SZ_64M+SZ_32M): size2 = size - SZ_64M; size -= SZ_64M; break; case (SZ_128M+1) ... (SZ_128M+SZ_64M): size2 = size - SZ_128M; size -= SZ_128M; break; };
What if the size of your BAR is 128 MB + 64 MB + 32 MB ? Then you need three windows, and your algorithm doesn't work :-) Thomas -- Thomas Petazzoni, CTO, Free Electrons Embedded Linux, Kernel and Android engineering http://free-electrons.com