Peter Maydell <peter.mayd...@linaro.org> writes:
> When an ITS detects an error in a command, it has an > implementation-defined (CONSTRAINED UNPREDICTABLE) choice of whether > to ignore the command, proceeding to the next one in the queue, or to > stall the ITS command queue, processing nothing further. The > behaviour required when the read of the command packet from memory > fails is less clearly documented, but the same set of choices as for > command errors seem reasonable. > > The intention of the QEMU implementation, as documented in the > comments, is that if we encounter a memory error reading the command > packet or one of the various data tables then we should stall, but > for command parameter errors we should ignore the queue and continue. > However, we don't actually do this. To get the desired behaviour, > the various process_* functions need to return true to cause > process_cmdq() to advance to the next command and keep processing, > and false to stall command processing. What they mostly do is return > false for any kind of error. > > To make the code clearer, replace the 'bool' return from the process_ > functions with an enum which may be either CMD_STALL or CMD_CONTINUE. > In this commit no behaviour changes; in subsequent commits we will > adjust the error-return paths for the process_ functions one by one. > > Signed-off-by: Peter Maydell <peter.mayd...@linaro.org> Reviewed-by: Alex Bennée <alex.ben...@linaro.org> -- Alex Bennée
