On Fri, 2016-03-11 at 10:18 +0000, Qianyu Gong wrote: > Hi Scott, > > > -----Original Message----- > > From: Scott Wood [mailto:[email protected]] > > Sent: Tuesday, February 23, 2016 8:12 AM > > To: Qianyu Gong <[email protected]>; [email protected]; york sun > > <[email protected]> > > Cc: Mingkai Hu <[email protected]> > > Subject: Re: [PATCH] armv8/fsl-layerscape: add IFC fixup for LS1043A with > > QSPI > > enabled > > > > On Mon, 2016-02-22 at 18:05 +0800, Gong Qianyu wrote: > > > QSPI and IFC are pin-multiplexed on LS1043A. So if QSPI is enabled, > > > IFC should be disabled. > > > But just disable IFC driver in LS1043A Linux is not enough because > > > mdio-mux will access IFC address space -- actually it accesses FPGA > > > which is connected to IFC CS3. So disable the whole IFC node in Linux > > > device tree. > > > > > > Signed-off-by: Gong Qianyu <[email protected]> > > > > > > diff --git a/arch/arm/cpu/armv8/fsl-layerscape/fdt.c > > > b/arch/arm/cpu/armv8/fsl-layerscape/fdt.c > > > index 4e4861d..5bb3048 100644 > > > --- a/arch/arm/cpu/armv8/fsl-layerscape/fdt.c > > > +++ b/arch/arm/cpu/armv8/fsl-layerscape/fdt.c > > > @@ -204,4 +204,11 @@ void ft_cpu_setup(void *blob, bd_t *bd) #ifdef > > > CONFIG_FSL_LSCH3 > > > fdt_fixup_smmu(blob); > > > #endif > > > + > > > +#ifdef CONFIG_LS1043A > > > +#ifdef CONFIG_FSL_QSPI > > > + do_fixup_by_compat(blob, "fsl,ifc", > > > + "status", "disabled", 8 + 1, 1); #endif > > > #endif > > > } > > > > This muxing is done at runtime, right? It isn't a case of the board > > hardwiring one > > or the other? In that case, it should be handled at runtime here as well. > > At a > > minimum, allow the user to use hwconfig to choose which they want to be > > accessible. Ideally there would be something in the device tree to list > > the reason(s) > > for a device being disabled, so the OS knows it can regard the device as > > being > > enabled if it knows about and enables them all. > > > > -Scott > > Sorry for the late reply. We have been asking the silicon team for the > details of the pin > muxing these days. > The conclusion is that all IFC interfaces(cs0/cs1/cs2) are disabled as long > as QSPI is > enabled on LS1043AQDS board. > As I know, this muxing won't be handled in kernel. Since IFC is disabled in > U-Boot, > IFC node would better be disabled in kernel as well. > Also in such cases, users have no other choice.
Why should the user not have a choice to choose IFC over QSPI? Where is the muxing configured? -Scott _______________________________________________ U-Boot mailing list [email protected] http://lists.denx.de/mailman/listinfo/u-boot
