USB GPU benchmarking (#36840)

* test boot time

* lil nicer

* cleanup

* revert that

---------

Co-authored-by: Comma Device <device@comma.ai>

scripts/usbgpu/benchmark.sh

@@ -0,0 +1,26 @@
+#!/usr/bin/env bash
+set -e
+
+DIR="$( cd "$( dirname "${BASH_SOURCE[0]}" )" >/dev/null && pwd )"
+cd $DIR/../../tinygrad_repo
+
+GREEN='\033[0;32m'
+NC='\033[0m'
+
+
+#export DEBUG=2
+export PYTHONPATH=.
+export AM_RESET=1
+export AMD=1
+export AMD_IFACE=USB
+export AMD_LLVM=1
+
+python3 -m unittest -q --buffer test.test_tiny.TestTiny.test_plus \
+  > /tmp/test_tiny.log 2>&1 || (cat /tmp/test_tiny.log; exit 1)
+printf "${GREEN}Booted in ${SECONDS}s${NC}\n"
+printf "${GREEN}=============${NC}\n"
+
+printf "\n\n"
+printf "${GREEN}Transfer speeds:${NC}\n"
+printf "${GREEN}================${NC}\n"
+python3 test/external/external_test_usb_asm24.py TestDevCopySpeeds