Gr2 Gl Loop

GR2 / IMPACT OpenGL test loop

Written for GR2 first; everything carries over to IMPACT with the board's own monitor commands (mgras ... for gr2 ...). See "IMPACT (MGRAS)" below for what differs.

Drive one GL configuration at a time through the real IRIX GL stack (libglcore EXPRESS -> HQ2 FIFO -> our HLE in src/dev/gr2/{hq2,gl}.rs) and check the pixels. Each glprim run draws exactly one primitive, so its FIFO trace is short and every option flips one piece of state or one address bit.

Pieces

IMPACT (MGRAS) on the Indigo2 R10000 (IP28)

• Config ignore/ip28/iris.toml ([graphics] board = "solidimpact" | "highimpact" | "maximpact"), disk ip28_6522_realhw.raw written directly (never kill iris while IRIX runs). Root has a password: p00pp00p. tools/irix-sh.py takes --password or IRIS_ROOT_PASSWORD=p00pp00p (glprim-case.py passes the environment on).
• The user builds target/release/iris with --features gr4-jit,jitv2,lightning,opcodefusion,rex-jit: do not overwrite it. Build your own with --target-dir target/claude (same features) and run target/claude/release/iris --config ignore/ip28/iris.toml from the repo root (the Bash cd wrapper is broken: cd ... && exec ... inside one command works, as does run_in_background). The CPU starts by itself; this build exits on guest power-off, so after shutdown just wait for the pid to go.
• Monitor from the shell: tools/mon.py "mgras status" "rss regs" ... (the MCP run_command has been seen returning the previous command's output). Useful: mgras status|xmap|pix X Y|stats|jit|fbdump DIR|shot F.png|trace F [hq,rss,cpu,tex|all]|rec F|rec off, rss regs (decodes the IR, shows each raster engine's backlog), locks (who holds what).
• /tmp is emptied at boot: re-copy and rebuild gltest each boot (cp /shared/gltest/* /tmp/gltest/ && sh irix.sh gltest glprim). /shared mounts by itself on this image.
• Desktop readiness: telnet comes up first; wait for 4Dwm and then toolchest in ps -ef, plus ~15 s, before screenshots; then xset s off.
• tools/glprim-case.py detects the board. IMPACT's scanout applies the DAC gamma (SGI default 1.7), so mid-level colours read back brighter than GR2's (the pink clear 1, 0.5, 0.75 shows as ffaad7); probe saturated colours, or check values with glprim --read ... --check. glprim picks the deepest visual by default (12,12,12, which the raster JIT leaves to the interpreter): use --visual 8,8,8,8 for the JIT path.
• Textures: tools/gltex-matrix.py runs glprim's tex scene over formats and sizes and checks every texel's raw framebuffer word (all pass as of 48089c43). Several GL clients share TRAM through the texture manager's page saves and restores (tl_spec 0xd60 loads in mgras trace F hq,tex): a bug there damages every client.
• Performance: board-bound runs slow the guest clock (lost ticks), so guest-side gltest --bench is meaningless (see rules/mgras/guest-gl-benchmarks-miss-board-time.md). Record the session (mgras rec F ... mgras rec off) and time its replay offline with MGRAS_REPLAY_NOCHECK=1 MGRAS_REPLAY_BOARD=high|max MGRAS_REPLAY=F cargo test --release --target-dir target/claude --lib --features gr4-jit mgras_replay_file -- --nocapture (wall time + final state hash).
• Goldens: MGRAS_REPLAY=ignore/mgras-golden/desktop2.rec must pass every checkpoint (also with MGRAS_REPLAY_BOARD=max). irix6522-boot.rec is stale (11 of 16 checkpoints fail at 35a40840 too).
• Hardware findings go in ignore/gr4/*.h (its own git repo; the user commits it), design notes in rules/mgras/.

Boot

1. cargo build --release --features developer (developer: monitor tooling; do not combine with lightning).
2. Start it with the Bash tool's run_in_background: true, as a command of its own (target/release/iris > <scratchpad>/iris-run.log 2>&1). A nohup ... & inside a chained command does not survive the command, and starting it right after killing the old process can fail: check pgrep -a iris before going on. (config: iris.toml, Indy R5000 + XZ, disk scsi1.raw.)
3. Start the CPU through the MCP: run_command("cpu start") (check with get_status if unsure).
4. tools/irix-sh.py wait --timeout 900 returns once telnet answers with a login prompt (network and inetd are up; X/xdm come up around then too).
5. tools/irix-sh.py mount-shared.
6. GL needs a logged-in desktop (xdm's clogin holds the display otherwise). root autologin is set up: /etc/autologin = root, and the ONE-SHOT flag /etc/autologin.on, which clogin deletes when it logs in. Re-create it (touch /etc/autologin.on) every boot before shutdown. The session takes ~1 min after telnet comes up: wait until ps -ef | grep 4Dwm shows it.
7. The screen saver (haven + /usr/sbin/bongo, octahedra) takes over the whole screen after 10 min idle and every probe reads black. The desktop re-applies its saver settings after /root/.sgisession, so run /usr/bin/X11/xset s off once the session is up, and check xset q | grep timeout: = 0.
8. Stopping iris: kill it by its exact pid (ps -eo pid,args | grep '[t]arget/release/iris$'). pgrep -f target/release/iris also matches the shell running the command and kills it.

iris.toml currently writes the disk image directly (no overlay): never kill iris while IRIX is running (see Shutdown).

Build glprim in the guest

mkdir -p shared/gltest && cp test/gltest/{glprim.c,main.c,irix.sh} shared/gltest/
tools/irix-sh.py run 'mkdir -p /tmp/gltest && cp /shared/gltest/* /tmp/gltest/' \
                     'cd /tmp/gltest && sh irix.sh glprim 2>&1'

Every session gets DISPLAY=:0.0, /bin/sh, cwd /tmp. The exit status of irix-sh.py run is the last command's status (124 = timeout/connection).

One test case

Preferred: tools/glprim-case.py CASE [--probe gx,gy[=rrggbb]]... [--notrace] -- <glprim options> does all of the below (trace, run, window origin, probes in GL window coordinates, fbdump, crop of the window to $GLPRIM_OUT/CASE.png, trace off, kill glprim) and exits with the number of failed probes. It talks to the monitor on 127.0.0.1:8888 directly (works alongside the MCP). Stage the sources first (cp test/gltest/* shared/gltest/, then copy to /tmp in the guest and sh irix.sh glprim).

By hand:

run_command("gr2 trace /tmp/gl-<case>.log all")        # MCP
tools/irix-sh.py run 'cd /tmp/gltest && ./glprim <options> --hold 4000'
run_command("gr2 fbdump /tmp/gl-<case>")                # during the hold, or
run_command("gr2 pix <x> <y>")                          # spot checks (display coords)
run_command("gr2 trace off")

Run the capture commands while --hold keeps the window up (launch the guest command in the background with & if you need to sample during the hold). glprim prints its configuration and its real window origin (window origin OX,OY size WxH; the window manager moves windows). A GL window pixel (gx, gy) is display pixel (OX + gx, OY + H - 1 - gy).

Default geometry (unit square scaled to the viewport, glOrtho 0..w, 0..h): triangle (0.2w,0.2h) red, (0.8w,0.2h) green, (0.5w,0.8h) blue. Flat shading uses the provoking vertex (last vertex for triangles/strips/fans/quads, the FIRST vertex for GL_POLYGON). Clear default is pink (1, 0.5, 0.75) = rgb=ff80bf.