Lameen of Jabal al-Lughat has an intriguing post about “a Mauritanian Arabic-based pidgin recorded by the medieval geographer Al-Bakri” that he says “may well be the earliest attested passage in a pidgin, and certainly the earliest Arabic-based pidgin reported.”
The near-absence of morphology, the apparent presence of tense particles, and the simplification of the phonology are all suggestive of a pidgin, and a pidgin is exactly what one would expect given the nature of the trans-Sahara trade. Phonetically, the substitution of ‘ for qāf is characteristic of lower Egypt and the Levant, but also of several city dialects in the Maghreb and of Maltese; the substitution of d for j is widespread in upper Egypt, but I know of no modern dialect that has both features.
See his post for the passage in Arabic, in Lameen’s suggested transcription, and in Thomason and Elgibali’s tentative translation (it’s a variation on the old joke about the man and his son trying to ride a camel with the least amount of flak from passersby), and for the frustrating facts of its publication. I hope the manuscript source turns up someday!