Date: Mon, 28 Nov 2005 22:59:48 -0700 (MST) From: "M. Warner Losh" <imp@bsdimp.com> To: fierykylin@gmail.com Cc: freebsd-hackers@freebsd.org Subject: Re: puzzle about the pci_add_child Message-ID: <20051128.225948.82990411.imp@bsdimp.com> In-Reply-To: <87ab37ab0511280850y1bca554n1da9b11c321be34b@mail.gmail.com> References: <87ab37ab0511280850y1bca554n1da9b11c321be34b@mail.gmail.com>
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In message: <87ab37ab0511280850y1bca554n1da9b11c321be34b@mail.gmail.com> kylin <fierykylin@gmail.com> writes: : i am reading the pci code of freeBSD 53 ,and come to the puzzle of : pci_add_child. : 1 : why should we =09pci_cfg_save(dinfo->cfg.dev, dinfo, 0); after we have : already fill the cfg in pci_read_device ? It hasn't been completely filled in by pci_read_device. : 2 : what 's the purpose of the function couple : pci_cfg_save(dinfo->cfg.dev, dinfo, 0); : pci_cfg_restore(dinfo->cfg.dev, dinfo) : below is the function ,thank u Power state gets set to D0 as a side effect so that the device is live for the probe. Warner
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