ARM32 was nearly 15 years old by that point (the ARM700, the first 32 bit core dates to 1993).
Maybe not exciting but the ARM32 had the bulk of its life before the iPhone, ARM64 came shortly after. Old and boring for the original iPhone ISA was also intentional.
sorry i shouldn't have said "arm architecture" there obviously arm32 wasnt anything new: i figured that was implied. we wanted specifics on the S5L8900 and they were (and still are) quite hard to come by. this contributed to the discovery and instrumentation of DFU mode, iboot, etc that contributed to jailbreak
Less “intentional” and more “unavoidable”. There was limited runway to fix the S5L8900 design, the Cortex A8 wasn’t ready at tapeout, and so the ARM1176 was it. If Broadcom hadn’t looked like they were fumbling the BCM2730 it would have been an ARM1132 instead, and history would have been a little different.
And yet those are all 32 bit ARM cores. Which in some way was "unavoidable" as I don't know what viable alternatives existed for a phone SoC in 2007, though someone can correct that.
ARM1132? That is not a core I have ever heard of nor can find any reference to. I assume it would be some ARMv6 ARM11 though, a uarch that was already quite mature by the time the iphone rolled around.
