fix(scheduler): defer warp_pcs[0] init out of reset block (#334)#357
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gautamdev17 wants to merge 1 commit into
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fix(scheduler): defer warp_pcs[0] init out of reset block (#334)#357gautamdev17 wants to merge 1 commit into
gautamdev17 wants to merge 1 commit into
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…u#334) Non-constant reset assignment (base_dcrs.startup_addr) inside if(reset) is illegal in ASIC synthesis. Introduces 'initialized' flag: reset block uses constants only; warp_pcs[0] and active_warps[0] set atomically one cycle after reset deassertion so warp 0 never schedules with PC=0.
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Fixes #334
Problem
warp_pcs[0]was being assigned frombase_dcrs.startup_addrinside the reset block. This is not allowed in ASIC synthesis,reset assignments must be constants, not runtime signals.Fix
Added a
reg initializedflag that starts at0on reset. On the first cycle after reset,warp_pcs[0]andactive_warps[0]are loaded together, so warp 0 only becomes schedulable once it has the correct boot address. All other scheduler logic runs normally after that.This adds one extra cycle before the first instruction is fetched,which has no practical impact.