I think PowerPC's IO_SPACE_LIMIT is defined incorrectly. On 64-bit, it's currently set to 0xffff'ffff'ffff'ffff. This can't possibly work, there's no way for the PCI bus to transmit 64-bit IO-port addresses. It should probably be defined to 0xffffffffU > -----Original Message----- > From: Jesse Barnes [mailto:jbarnes@xxxxxxxxxxxxxxxx] > Sent: Wednesday, May 06, 2009 9:24 AM > To: Yinghai Lu > Cc: Stephen Rothwell; linux-next@xxxxxxxxxxxxxxx; Wilcox, Matthew R; > Benjamin Herrenschmidt > Subject: Re: linux-next: IO BAR sizing warning > > On Wed, 06 May 2009 00:21:20 -0700 > Yinghai Lu <yinghai@xxxxxxxxxx> wrote: > > > Stephen Rothwell wrote: > > > Hi Jesse, > > > > > > Today's linux-next build (powerpc ppc64_defconfig) produced this > > > warning: > > > > > > drivers/pci/probe.c: In function '__pci_read_base': > > > drivers/pci/probe.c:196: warning: large integer implicitly > > > truncated to unsigned type > > > > > > Probably introduced by commit > > > 82160fd142cdf6956a677120426bf5baefcc7cf9 ("PCI/x86: don't assume > > > prefetchable ranges are 64bit"). > > > > > > > --- a/drivers/pci/probe.c > > +++ b/drivers/pci/probe.c > > @@ -193,7 +193,7 @@ int __pci_read_base(struct pci_dev *dev, enum > > pci_bar_type type, res->flags |= pci_calc_resource_flags(l) | > > IORESOURCE_SIZEALIGN; if (type == pci_bar_io) { > > l &= PCI_BASE_ADDRESS_IO_MASK; > > - mask = PCI_BASE_ADDRESS_IO_MASK & 0xffff; > > + mask = PCI_BASE_ADDRESS_IO_MASK & > > IO_SPACE_LIMIT; > > > > > > and > > > > for x86: > > #define IO_SPACE_LIMIT 0xffff > > > > for powerpc > > arch/powerpc/include/asm/io.h:#define IO_SPACE_LIMIT ~(0UL) > > > > maybe we need to change back that line... > > Yeah that would be easy enough. Though really it seems like > IO_SPACE_LIMIT should be applied, with an appropriate cast. Looks like > this code has been there for a long time, and maybe there are devices > that allow the upper 16 bits of their IO BARs to be set even though > they don't honor them (they should hardwire them to 0 in that case), > but spec-wise allowing the full size should be fine... > > Matthew & Ben, any comments? > > -- > Jesse Barnes, Intel Open Source Technology Center ��.n��������+%������w��{.n�����{��w����ܨ}���Ơz�j:+v�����w����ޙ��&�)ߡ�a����z�ޗ���ݢj��w�f
