On 11/16/2012 09:17 PM, Elliott Mitchell wrote: > On Fri, Nov 16, 2012 at 06:13:56PM +0100, Hauke Mehrtens wrote: >> On 11/16/2012 05:44 AM, Elliott Mitchell wrote: >>> I happened to be browsing the linux-mips git repository and noticed the >>> commit at Tue, 10 Jul 2012 16:16:47. >> >> What commit are you talking about? Do you have a commit id? > > Looking at: http://git.linux-mips.org/?p=ralf/linux.git;a=commitdiff;h=1dfef20a4cf82997d4c7520138ed8188a181241c > > I'm guessing "1dfef20a4cf82997d4c7520138ed8188a181241c" is the commit id. > > Subject is: "brcmsmac: remove PCI_FORCEHT() macro" > > Description is: > The BCM4716 is a SoC and does not have a PCI client interface, so this > condition is never true. > > Acked-by: Arend van Spriel <arend@xxxxxxxxxxxx> > Signed-off-by: Hauke Mehrtens <hauke@xxxxxxxxxx> > Signed-off-by: John W. Linville <linville@xxxxxxxxxxxxx> > > I'm guessing the piece of code is invoked on all flavors of bcm471[678], > so while it doesn't get invoked on most devices, some of them it > definitely can be. I have never seen a bcm4718 with a PCIe controller running in client mode and it does not make sense to me. PCIe client mode means it is connected to some other controller like in a Intel chipset in a desktop PC, but there you would use a normal PCIe card and not a SoC. The controller is normally running in host mode, so an other PCIe card like the BCM43224 could be connected to the PCIe controller in the SoC. I have a Netgear WNDR3400 with a BCM4718 and a BCM43224 connected to the PCIe host controller in the SoC. >>> The Broadcom 4716 *does* have an external PCI Express interface! Take a >>> look at the images on http://wiki.openwrt.org/toh/asus/rt-n16 If you >>> look at the image of the underside >>> (http://wiki.openwrt.org/_media/inbox/rt-n16_back_hires.jpg) on the right >>> side, CON3 and CON5 are the solder pads for mounting a mini-PCIe >>> connector and bracket. Apparently V11 is a voltage regulator needed for >>> that to work, but on this an example of a Broadcom 4716 board that really >>> does allow a useable PCIe interface (with some hardware hacking). >> >> Are you sure the Asus rt-n16 has a BCM4716 and not an BCM4718? Both have >> the same chip id (0x4716), but a different revision number (BCM4716 = >> rev 8, BCM4718 = rev 10). The BCM4716 and BCM4717 do not have a PCIe >> controller, just the BCM4718 has one [0]. > > I'm not actually. Currently exploring a device with ASUS's minimal shell > they give you. According to /proc/cpuinfo, "system type: Broadcom > BCM4716 chip rev 1 pkg 10". If I'm looking at the correct byte in > /sys/devices/[...]/config, it does in fact appear to be 0x0A (decimal > 10). So it is a BCM4718 with a PCIe controller. > I've seen photos of some people in Taiwan who soldered something at V11 > (presumably a voltage regulator, it's all Chinese to me). I'm guessing > they did in fact get a MiniPCIe card to work, but everything is in the > wrong language. :-) The crucial build photo of the regulator module > has disappeared, so it is more difficult to reconstruct. Yes that could be possible and mainline linux would support such a setup. Be aware that the PCIe controller in the BCM4718 reorders some of the PCIe writes and reads, which causes some problems. Hauke
