On Wed, Dec 8, 2010 at 9:14 AM, Marcin Juszkiewicz marcin.juszkiewicz@linaro.org wrote:
Dnia wtorek, 7 grudnia 2010 o 17:50:50 Dave Martin napisał(a):
You can't built a kernel for pre-v7 platforms with CONFIG_THUMB2_KERNEL: the code can't run on those platforms because they don't support Thumb-2.
So anything inside #ifdef CONFIG_THUMB2_KERNEL can assume v7/Thumb-2 capable (and hence reasonably new) tools.
Wasn't Thumb2 available in arm1176 cores? So it would be v6 too.
No-- arm1136 and arm1176 only support the original 16-bit Thumb-1 instruction set (with some extensions specific to v6 like some v6 SIMD operations, architected BKPT etc., etc.)
There is an extended v6 architecture, v6T2. However, this is only implemented by the arm1156 processor, which is rare and not supported by the Linux kernel at the present time IIUC.
Cheers ---Dave