What are the main/important features added/updated?
Thank you.
Hello,
Cortex-A9 and Cortex-A7 are almost the same. Both are Armv7-A processors.Because Cortex-A7 is the successor of the Cortex-A9, its power efficiency became increased and has some extentions such as hardware division instruction, Large Physical Address Extensions (LPAE) and so on.Please find attached figure shows some comparisons (source: Arm).Cortex-A7 can also be used for the little core of the bug code such as Cortex-A15 or Cortex-A17 in so called big.LITTLE configuration because the bus interface became AMBA4 ACE. AXI bus interface of Cortex-A9 cannot be used for the little core.Regarding Cortex-A53, it is ARMv8-A (i.e. 64bit architecture).The instruction set is not compatible with Armv7-A although the philosophy has inherited Armv7-A.Therefore, it is definitely different from Cortex-A9 or Cortex-A7.However, AArch32 mode of Cortex-A53 can emulate the Armv7-A (i.e. Cortex-A9/7).
Best regards,
Yasuhiko Koumoto.
Notice that the Cortex-A9 is slightly quicker than the Cortex-A7, so the Cortex-A9 is still going strong.
Hello Jens,
of course, I love Cortex-A9 rather than Cortex-A7.
However, in the recent press release, some vendors hide that its product is used Cortex-A9 and say only it is used just Armv7-A processor. I wonder it is an ashamed thing to say they are using Cortex-A9.
Cortex-A7 seems to have become very famous because of Raspberry Pi2.
I think Cortex-A7 is also great processor.
I will add the performance comparison between Cortex-A7 and Cortex-A53 from the Arm site.
should A9 be the successor of A7? From the name, A9 should came later than A7?
Hello hellomoon,
no, the order of bitrh is A8, A9, A5, {A15, A7}, {A57, A53}, A12, A17, A72.
One tiny detail to add, which you might want to know if you're going for the AAE ... The Cortex-A12 and Cortex-A17 were two different cores, but later the Cortex-A12 was renamed to Cortex-A17. Still, I've seen at least one implementation with the name "Cortex-A12" printed on it; this is because it was before ARM decided to name it Cortex-A17.
Hello Jens Bauer,
do you say that the latest Cortex-A12 can become a big core for Cortex-A7?
The original Cortex-A12 had normal AXI bus and could not keep coherency with the LITTLE core.
I just re-read the information I noticed last year; perhaps I didin't understand it correctly.
Quote:
"Originally, the Cortex-A12 and Cortex-A17 processors were launched as two distinct parts, as they delivered different feature sets and performance points. Since then, due to the consistent demand for more performance and efficiency from the market, alongside Arm’s focus on continuously improving the products, has led us to introduce the performance improvements added by the Cortex-A17 processor into the latest maintenance release of the Cortex-A12. Now both processors deliver equivalent performance levels"
-But you've already seen that a year ago, so I believe you're right; the Cortex-A12 is not exactly the same as Cortex-A17.
I still expect that the Cortex-A17 will be more attractive for the silicon vendors than the Cortex-A12.