You can find the driving or walking route from Datong, Shanxi to Lhasa, Tibet from Baidu or Google Maps
I searched some information for you, it is the route from Yuncheng, Shanxi to Lhasa , for your reference, you have to pass through Yuncheng to reach Lhasa anyway, I hope it can help you.
Yuncheng City - Lhasa City, Tibet Autonomous Region
Purchasing items: Before entering Tibet, you can go to your local pharmacy to buy related anti-altitude reaction drugs. Recommendations: Rhodiola rosea capsules, Novo Drugs such as Dikang Capsule, Gaoyuanning, Gaoyuankang, etc. should be taken at least 3 days in advance. Prepare some food before departure, including American ginseng, vitamin C, fruits, raisins, chocolate, and biscuits. If women are afraid of the sun, bring sunscreen, a sun hat, and sunglasses. If you go to Tibet from June to September, prepare a 2-piece set of clothes, a long-sleeved shirt and a jacket. If you go to Mount Everest, you need to bring a down jacket. The weather in Tibet in summer is generally sunny during the day and rainy at night, with a large temperature difference. It’s about 26 degrees during the day and about 8 degrees at night. Be careful not to catch a cold and go to Tibet.
Starting point Yuncheng
Destination Lhasa
Distance 3,059 kilometers
Take 2 days and 10 hours
Route Yuncheng→ Yunfeng Expressway→ Fenglingdu Yellow River Bridge→ County Road 319→ Xitong Expressway→ Yanliang/Tongchuan/Chengbei/Xianyang/Airport/Baoji/Ring Expressway→ Huxian/Zhangbagou→ Xihan Expressway→ Erhe Expressway → 108 National Highway → Mian-Guang Expressway → Cheng-Mian Expressway → Chengdu/Ya’an/Baijia → Chengya Expressway → Ya’an/Leshan/Meishan → G318/Duoying/Xikang Bridge → 318 National Highway → Xiangyang Avenue → Huancheng Road → 318 National Highway/Yanjiang Road→ 214 National Highway→ Quanzhou Road→ 318 National Highway/Xiamen Road→ Jiangsu Road→ South Section of Linkuo East Road→ Lhasa
Practical Operation
1. From {Hedong East Street } Go {west} to {Renmin South Road} 1.0 km
2. Turn slightly {right} and take {Liberation South Road} 0.1 km
3. Slightly turn {right} Turn {left} and continue along {Jiefang South Road} for 1.4 kilometers
4. Turn {left} at {Gongnong West Street} for 1.8 kilometers
5. At the circular At the intersection, take the {2nd} exit and take the {Yunfeng Expressway}. The toll for some sections is 89.7 kilometers
6. Turn slightly {left} and head towards {Fenglingdu Yellow River Bridge} for 0.5 thousand meters
7. Continue straight into {Fenglingdu Yellow River Bridge} 1.6 kilometers
8. Turn {left} on {319 County Road} for 20 meters
9. Take the ramp to {Xitong Expressway}. Some sections are tolled 0.5 kilometers
10. At the intersection, continue to the {left} in the direction of {Xitong Expressway} and go {west Tong Expressway} This section has a toll of 125 kilometers
11. Get off the {Yanliang/Tongchuan/Chengbei/Xianyang/Airport/Baoji/Ring Expressway} exit and go to {Ring Expressway} This section has a toll of 0.4 thousand meters
12. At the intersection, continue to the {left} in the direction of {Beltway} and take {Beltway}. The toll for this section is 33.5 kilometers
13. Get off at the {Huxian/Zhangbagou} exit and go to {Xihan Expressway}. The toll for this section is 0.3 kilometers
14. At the intersection, continue to the {left} in the direction of {Xihan Expressway} and walk {Xihan Expressway} The toll for this section is 288 kilometers
15. Keep going and take the {Erhe Expressway}. The toll for some sections is 54.3 kilometers
16. Keep going and get on the {Erhe Expressway} 108 National Highway} 20.7 kilometers
17. Take the ramp to {Mian-Guang Expressway} This section has a toll of 226 kilometers
18. Continue forward and take this section of {Cheng-Mian Expressway} The toll is 91.7 kilometers
19. Exit the exit and go to {Beltway}. The toll for this section is 0.6 kilometers
20. At the intersection, continue along the direction pointing to {Beltway} Go {left} and take the {Ring Expressway}. The toll for this section is 36.2 kilometers
21. Get off at the {Chengdu/Ya'an/Baijia} exit and go to {Chengdu-Ya Expressway}. The toll for this section is 0.1 kilometers.
22. Get off at the {Ya'an/Leshan/Meishan} exit and take the {Chengya Expressway}. The toll for this section is 131 kilometers
23. Get off at the {G318/Duoying/Xikang Bridge} exit , heading to {318 National Highway}, the toll for some sections is 0.9 kilometers
24. Turn slightly {right} on {318 National Highway} for 30.1 kilometers
25. Turn slightly {Xiangyang Avenue} Turn {right} 0.6 km
<p>26. Turn {right} and continue along {Xiangyang Avenue} for 16 meters
27. {Turn around} 58 meters
28. At the second intersection, go { Turn right} and enter {Xiangyang Avenue} for 1.4 kilometers
29. Turn slightly {left} and continue along {Xiangyang Avenue} for 0.4 kilometers
30. Continue forward OK, take {Huancheng Road} for 0.5 kilometers
31. Continue forward, take {318 National Highway/Yanjiang Road} and continue along 318 National Highway for 87.0 kilometers
32. Turn {right} and continue along {318 National Highway} for 64.4 kilometers
33. Turn {right} and continue along {318 National Highway} for 1.5 kilometers
34. Turn sharply {right} and continue along {318 National Highway} for 62.9 kilometers
35. Turn {right} and continue along {318 National Highway} for 427 kilometers
36. Turn {right} and continue along {318 National Highway} for 0.3 kilometers
37. Turn {left} and continue along {318 National Highway} for 117 kilometers
p>38. Turn {left} on {214 National Highway} for 173 kilometers
39. Turn {right} and continue along {214 National Highway} for 41.3 kilometers
40. Turn {left} sharply on {318 National Highway} for 183 kilometers
41. Turn {right} and continue along {318 National Highway} for 159 kilometers
42. Turn {left} and continue along {318 National Highway} for 60.1 kilometers
43. Turn {left} and continue along {318 National Highway} for 139 kilometers
44. Turn {left} on {Quanzhou Road} for 1.4 kilometers
45. Turn {right} on {318 National Highway/Xiamen Road} and continue along 318 National Highway for 128 kilometers
46. Turn {right} and continue along {318 National Highway} for 271 kilometers
47. Turn {right} and continue along {318 National Highway} for 1.0 Kilometers
48. At the roundabout, take the {3rd} exit onto {Jiangsu Road} 1.0 km
49. Turn {left at {Linkuo East Road South Section} } Turn 0.2 km
50. Turn {left}