On Sun, Feb 21, 2016 at 03:10:30PM +0200, Michael S. Tsirkin wrote: > On Sun, Feb 21, 2016 at 08:06:17AM -0500, Gabriel L. Somlo wrote: > > > > > > > > > +#if !(defined(FW_CFG_CTRL_OFF) && defined(FW_CTRL_DATA_OFF)) > > > > +# if (defined(CONFIG_ARM) || defined(CONFIG_ARM64)) > > > > +# define FW_CFG_CTRL_OFF 0x08 > > > > +# define FW_CFG_DATA_OFF 0x00 > > > > +# elif (defined(CONFIG_PPC_PMAC) || defined(CONFIG_SPARC32)) /* ppc/mac,sun4m */ > > > > +# define FW_CFG_CTRL_OFF 0x00 > > > > +# define FW_CFG_DATA_OFF 0x02 > > > > +# elif (defined(CONFIG_X86) || defined(CONFIG_SPARC64)) /* x86, sun4u */ > > > > +# define FW_CFG_CTRL_OFF 0x00 > > > > +# define FW_CFG_DATA_OFF 0x01 > > > > +# else > > > > +# warning "QEMU FW_CFG may not be available on this architecture!" > > > > +# define FW_CFG_CTRL_OFF 0x00 > > > > +# define FW_CFG_DATA_OFF 0x01 > > > > > > Better not try hacks like this, they are hard > > > to support down the road. Please only list what is tested and > > > actually exposed by QEMU. > > > > I was looking for a standard way to advertise register offsets within > > the ioport or mmio region assigned to fw_cfg, but right now the answer > > is "there isn't one", and "register offsets are an arch specific > > detail". As such, the only reasonable way I saw was to copy the same > > values used in the QEMU source. > > > > See also: > > https://lists.gnu.org/archive/html/qemu-devel/2015-11/msg05037.html > > > > Thanks much, > > --Gabriel > > My point is you don't know what will qemu do on these > other arches which do not at the moment have fw cfg. > So don't try to guess! Oh, you mean for the "else". I originally wanted to be able to compile this on any architecture and wanted some dummy defaults I could override on the command line. But now we're already restricting this to known architectures only, so I'll send a patch turning the warning into an error, and removing the #defines for the "else" branch above. Sorry I misunderstood you the first time around :) Thanks, --Gabriel -- To unsubscribe from this list: send the line "unsubscribe linux-api" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
