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Ian Campbell
f01af57300
',' is a valid character in a device-tree path (see ePAPR v1.1 Table 2-1), in fact ',' is actually pretty common in node names. Using ',' as a separator breaks for example on fast models. If you use the full path (/smb/motherboard/iofpga@3,00000000/uart@090000) rather than the alias then earlyprintk gives: (XEN) Looking for UART console /smb/motherboard/iofpga@3 (XEN) Unable to find device "/smb/motherboard/iofpga@3" (XEN) Bad console= option 'dtuart' I actually noticed this on Jetson where the uart is "/serial@0,70006300" and there happened to be no alias defined. Instead use ':' as the separator, it is defined to terminate the path in the context of /chosen/stdout-path (Table 3-4) which is pretty closely analogous to the dtuart= option and so makes a pretty good choice (especially since the next patch adds support for stdout-path). Since no DT aware driver current supports any options there is no point in retaining support for ',' for backwards compatibility. Additionally, expand the buffer for the dtuart option, a path can be far longer than 30 characters (in fact the maximum size of a single node name is 31, so it's not even necessarily enough for an alias). 128 is completely arbitrary and allows for paths at least 8 deep even with worst case node names. Signed-off-by: Ian Campbell <ian.campbell@citrix.com> Reviewed-by: Julien Grall <julien.grall@linaro.org>