On Fri, Feb 17, 2023 at 03:24:04PM -0800, Randy Dunlap wrote: > > > On 2/17/23 03:57, Thomas Bogendoerfer wrote: > > On Wed, Feb 15, 2023 at 10:59:35PM -0800, Randy Dunlap wrote: > >>> I agree this is where this variable has be be declared / initialized, > >>> but having this dependent on CONFIG_MIPS_MALTA/CONFIG_LANTIQ machines > >>> doesn't seem right. > >> > >> So far I have been able to consolidate the LANTIQ code into a general > >> patch, but not MALTA. > > > > if I didn't miss something physical_memory is always 0 for LANTIQ > > and something for MALTA depending on command line/DT. Now > > > > arch/mips/kernel/vpe-mt.c contains > > > > /* > > * The sde-kit passes 'memsize' to __start in $a3, so set something > > * here... Or set $a3 to zero and define DFLT_STACK_SIZE and > > * DFLT_HEAP_SIZE when you compile your program > > */ > > mttgpr(6, v->ntcs); > > mttgpr(7, physical_memsize); > > > > so the 0 for LANTIQ is fine with the correct VPE payload. But for > > MALTA could cause major problems, if the VPE payload uses the top > > of memory for it's stack. So I would guess nobody uses this "mode". > > Therefore let's get rid of physical_memory in vpe.c completly. > > Hi Thomas, > > What is this line doing? > mttgpr(6, v->ntcs); from a quick glance over the code, it's probably the number of thread contexts (TCs) the VPE is allowed to use. > Does it need to stay? yes. > But the comment and mttgpr(7, physical_memsize); can be deleted? replace it with /* * we don't pass the memsize here, so VPE programs need to be * compiled with DFLT_STACK_SIZE and DFLT_HEAP_SIZE defined */ mttgpr(7, 0); Thomas. -- Crap can work. Given enough thrust pigs will fly, but it's not necessarily a good idea. [ RFC1925, 2.3 ]
