Depends a lot on which route you take.
Here are a couple of decent eateries on the way for the NH-45 route (pls do update us if you find any new ones or if these have changed)
- While leaving, stop at "Arcot Biryani" in Porur (Poonamalle trunk road)

- Mid-way you can stop in Mettur at Madurai Sri Muniyandi Vilas Hotel in Mettur
If you take the Krishnagiri route, you can consider:
- Red Chili after Sriperumbudur
- Sakthi Ganapathy & Kanaka Sarovar just before the Arakkonam bridge
- Grand Krishna Sathuvachari
- Motel Deepam just before Pallikonda toll plaza (the cleanest toilets I have seen on this stretch)
- Motel Landmaark (opposite side of road) - 3 km after Ambur town
- Hotel Tamilnadu TTDC just before the Krishnagiri bridge