On 08/07/15 22:40, Kevin O'Connor wrote: > On Thu, Aug 06, 2015 at 04:59:15PM +0200, Marc Marí wrote: >> On Thu, 6 Aug 2015 10:47:21 -0400 >> "Kevin O'Connor" <ke...@koconnor.net> wrote: >>> Also, it's very unusual to see 32bit writes to an unaligned IO address >>> - I think two pad bytes should be added so that the offset for the dma >>> address is at position 4 (instead of 2). >> >> This is a PIO port (out), not a MMIO access (write). Maybe I'm wrong, >> but I don't think it matters to have the port number aligned with the >> write size. > > There was a thread on misaligned IO accesses recently: > > http://lists.nongnu.org/archive/html/qemu-devel/2015-07/msg05054.html > > Perhaps Stefan knows what the implications of misaligned IO writes > are. > > I suspect it's better to avoid them.
Unrelated, but I just noticed: in (and since) commit 457ba42878, ICH9_LPC_GEN_PMCON_1 is read with pci_config_read*w*, but rewritten with pci_config_write*l*. Is that intended? (My similar OVMF code writes a word, not a long.) Thanks Laszlo