The Seed-3 fit of the Ch443f scanout hardening exposed one setup family in the EMIF (iopll_0_outclk0, 3.225 ns) domain: u_zc_emit|u_z|cache_dirty -> awaddr[*], WNS -0.062 / TNS -0.203, skew-dominated (-0.064 clock skew; the 5-level logic path itself would land ~+0.002 at zero skew). Not the Ch443f logic — the added EMIF-domain logic nudged this marginal Ch357-era control path negative. Fix (Codex-directed, minimal): the normal-eviction AW address is a pure function of the cache line's beat, known when the line is installed. Preload it in S_FILL_C alongside cache_beat<=pf_beat (awaddr <= ZBASE + (pf_beat<<5)), and drop the two later awaddr assignments gated by cache_dirty (the scene_flush branch and the dirty cache-miss branch) — those now only assert awvalid on the already-prepared address. Clear-path awaddr assignments unchanged. No new FSM state, pipeline stage, buffer, or protocol change. Safe: a freshly filled line cannot be dirty before S_FILL_C installs it; the address is stable across hits and scene flushes; after a dirty eviction the next fill re-runs S_FILL_C; clear invalidates the cache so the first subsequent fill overwrites the clear address before any normal eviction. This removes the control cone rather than placing around it, so closure is seed-robust. Regressions green: z_rmw/zc_emit/axi_master_elastic/zbuffer/z_flush_writer/ tile_zflush, full Ch443f scanout set, sh3_zint (Z 0/53760, COLOR 0/11092), sh3_zrop (errors=0), and f52 byte-identity (Z 0/307200, COLOR 0/245760, drops=0). Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
rtl/gif_gs
GIF path and Graphics Synthesizer logic. Matches docs/contracts/gif_gs.md.
Current contents
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gs_stub.sv— GS shell with two architecturally distinct write ports (Ch75 namespace split):reg_wr_*— privileged-block writes (16-bit offset within0x12000000). LatchesBGCOLOR(offset0x00E0) intobg_{r,g,b}; other offsets emitEV_MODE.gif_reg_*— GIF A+D register-number writes (8-bit reg# + 64-bit data). DecodesPRIM=0x00,RGBAQ=0x01,XYZF2=0x04,XYZ2=0x05,FRAME_1=0x4C,ZBUF_1=0x4Einto per-register 64-bit latches; unknown reg numbers emitEV_MODE.- No VRAM, no drawing yet — that is the next architectural step.
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gif_path_stub.sv— Wave 2 minimal GIF packet logger; project-local single-qword register-write format. Used bytb_bgcolor_via_dma. -
gif_packed_stub.sv— real PS2 GIFtag parser (Ch72-Ch75). Handles PACKED (FLG=0), REGLIST (FLG=1), IMAGE (FLG=2), DISABLE (FLG=3). TheREAL_AD_REG_MAPparameter selects the A+D dispatch port:REAL_AD_REG_MAP=0(default, back-compat) — drivesgs_stub.reg_wr_*using a project-local 16-bit offset carried inin_data[79:64].REAL_AD_REG_MAP=1— drivesgs_stub.gif_reg_*using the real PS2 8-bit reg# carried inin_data[71:64]. Source-of-truth: PCSX2GSRegs.h.
BGCOLOR reset value
At reset, bg_{r,g,b} default to 0x40 each (mid-grey) rather than black.
Rationale: this makes "gs_stub reset but no BGCOLOR write yet" visually
distinct from "video output disabled / black frame" in Milestone A. Override
is a BGCOLOR write from the test harness.
Pitfall: namespace conflation
Ch74 conflated GIF A+D reg numbers with GS privileged-block offsets and
mapped e.g. 0x14→PMODE@0x0000. That is fiction — those are separate
namespaces. Ch75 split them. ZBUF_1 is 0x4E, not 0x4F (that's
ZBUF_2). When adding a new GIF-context register, source the reg# from
PCSX2 GSRegs.h, never from the privileged-block map.