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Re: A GnuTLS-Problem - problems fetchin emails using RISC OS

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On 23/12/2018 01:35, Ronald wrote:
> In message <1c559c6a57.beeb@-.->
>            Ronald <gettingchoppy@gmail.com> wrote:
> 
>> In message <pvmc4n$5ki$1@dont-email.me>
>>            druck <news@druck.org.uk> wrote:
>>> You can do 32bit neutral which is also compatible with the ARM2/3, but
>>> its larger and slower, and more ghastly - and as someone said - largely
>>> pointless (and yes I know one person is still using an ARM3 A4 laptop).
 >
> I might have got the wrong idea about architectures somewhere too,
> The Acorn32bitDev pdf states that machines before RiscPC including
> A7500 are 26bit only architecture armv2.

Archimedes, A3000s, and A5000s using the ARM2, ARM250 or ARM3, are all 
26bit only. All Risc PCs and A7000 using the ARM7500 are both 26bit and 
32bit capable.

> RiscPC 610 and newer are armv3and both 26bit and 32bit capable.

Yes, and that's the point Acorn should have moved to a 32bit OS. All the 
developers were still around, and everything could have been converted 
during the long testing period before the RPC launch.

Another opportunity would have been the introduction of the Strong ARM, 
although the original SA110 supported 26bit mode, it was clear when this 
mode was deleted from the SA1100 a short time later, that there would be 
no more 26bit mode chips.

Both those occasions required new software to take advantage of the new 
hardware or to address incompatibilities, which customers were more than 
willing to purchase. 32bit conversion could have been slipped in, and 
hardly anyone would have even been aware there was an issue.

> The 32bit SharedCLib must play a part too, maybe it wasn't possible on
> pre RiscPC, I can't remember.

The 32bit SCL was available for RISC OS 3.1

Most 32bit software was written to be neutral, so it will run in either 
26bit or 32bit mode, by not relying on the easy flag preserving nature 
of 26bit.

However to work on the ARM2 and ARM3, some extra hoops have to be jumped 
through to cater for the lack of the status register manipulation 
instructions (MSR/MRS) which are on the ARM6 and later. This is why you 
might find software works in 26bit mode, but is RISC OS 3.5 (ARM6) and 
later.

> I read that (generic) gcc v9 has dropped support for armv2 and armv3, no
> mention of armv4 but Armv5T 5TE 5TEJ remain supported. At the moment
> (gcc 4.7.4) we could possibly target the early architectures and cpu's
> additionly using -maps26 if necessary.

I'm not surprised, not only is no one using 26bit mode, but most code 
written for 32bit ARMs doesn't uses the Thumb2 mode (a mix of 16 & 32 
wide instructions), for increased code density. Unlike the very limited 
original 16 bit only Thumb1 instructions, Thumb2 can take full advantage 
of all processors registers and facilities, I don't like it though.

These days the completely different ARMv8 64 bit instruction set is all 
the range. I've just been on a course on the Cortex A53 for Zynq (SOC 
featuring a Xilinx FPGA), and it is very much "it's ARM Jim, but not as 
we know it".

> I imagine the DDE would have some flexibility for compatibility too.

Norcroft CC in DDE still supports ARM2 to XScale, I'm not sure if it 
knows anything later than ARMv5TE.

---druck

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A GnuTLS-Problem - problems fetchin emails using RISC OS Alexander Ausserstorfer <alexander.ausserstorfer@eclipso.at> - 2018-12-16 16:25 +0100
  Re: A GnuTLS-Problem - problems fetchin emails using RISC OS Ron <gettingchoppy@gmail.com> - 2018-12-17 11:32 +1300
    Re: A GnuTLS-Problem - problems fetchin emails using RISC OS Alexander Ausserstorfer <alexander.ausserstorfer@eclipso.at> - 2018-12-17 00:25 +0100
      Re: A GnuTLS-Problem - problems fetchin emails using RISC OS Ron <gettingchoppy@gmail.com> - 2018-12-17 13:25 +1300
        Re: A GnuTLS-Problem - problems fetchin emails using RISC OS Alexander Ausserstorfer <alexander.ausserstorfer@eclipso.at> - 2018-12-17 18:45 +0100
          Re: A GnuTLS-Problem - problems fetchin emails using RISC OS Ron <gettingchoppy@gmail.com> - 2018-12-18 09:27 +1300
            Re: A GnuTLS-Problem - problems fetchin emails using RISC OS Ron <gettingchoppy@gmail.com> - 2018-12-18 12:03 +1300
              Re: A GnuTLS-Problem - problems fetchin emails using RISC OS Alexander Ausserstorfer <alexander.ausserstorfer@eclipso.at> - 2018-12-19 18:57 +0100
                Re: A GnuTLS-Problem - problems fetchin emails using RISC OS Ron <gettingchoppy@gmail.com> - 2018-12-20 09:10 +1300
                Re: A GnuTLS-Problem - problems fetchin emails using RISC OS druck <news@druck.org.uk> - 2018-12-20 08:11 +0000
                Re: A GnuTLS-Problem - problems fetchin emails using RISC OS news@sprow.co.uk - 2018-12-20 00:00 -0800
                Re: A GnuTLS-Problem - problems fetchin emails using RISC OS Alexander Ausserstorfer <alexander.ausserstorfer@eclipso.at> - 2018-12-20 19:03 +0100
              Re: A GnuTLS-Problem - problems fetchin emails using RISC OS David Higton <dave@davehigton.me.uk> - 2018-12-20 19:52 +0000
                Re: A GnuTLS-Problem - problems fetchin emails using RISC OS Ronald <gettingchoppy@gmail.com> - 2018-12-21 09:58 +1300
                Re: A GnuTLS-Problem - problems fetchin emails using RISC OS Ronald <gettingchoppy@gmail.com> - 2018-12-21 13:28 +1300
                Re: A GnuTLS-Problem - problems fetchin emails using RISC OS news@sprow.co.uk - 2018-12-21 00:39 -0800
                Re: A GnuTLS-Problem - problems fetchin emails using RISC OS Ronald <gettingchoppy@gmail.com> - 2018-12-21 23:29 +1300
                Re: A GnuTLS-Problem - problems fetchin emails using RISC OS Alexander Ausserstorfer <alexander.ausserstorfer@eclipso.at> - 2018-12-22 04:11 +0100
                Re: A GnuTLS-Problem - problems fetchin emails using RISC OS Ronald <gettingchoppy@gmail.com> - 2018-12-23 00:37 +1300
                Re: A GnuTLS-Problem - problems fetchin emails using RISC OS Alexander Ausserstorfer <alexander.ausserstorfer@eclipso.at> - 2018-12-22 04:16 +0100
                Re: A GnuTLS-Problem - problems fetchin emails using RISC OS Martin <News03@avisoft.f9.co.uk> - 2018-12-22 11:34 +0000
                Re: A GnuTLS-Problem - problems fetchin emails using RISC OS David Higton <dave@davehigton.me.uk> - 2018-12-22 17:16 +0000
                Re: A GnuTLS-Problem - problems fetchin emails using RISC OS Ronald <gettingchoppy@gmail.com> - 2018-12-23 09:54 +1300
                Re: A GnuTLS-Problem - problems fetchin emails using RISC OS David Higton <dave@davehigton.me.uk> - 2018-12-22 21:23 +0000
                Re: A GnuTLS-Problem - problems fetchin emails using RISC OS David Higton <dave@davehigton.me.uk> - 2018-12-23 20:12 +0000
                Re: A GnuTLS-Problem - problems fetchin emails using RISC OS druck <news@druck.org.uk> - 2018-12-22 21:59 +0000
                Re: A GnuTLS-Problem - problems fetchin emails using RISC OS Ronald <gettingchoppy@gmail.com> - 2018-12-23 11:50 +1300
                Re: A GnuTLS-Problem - problems fetchin emails using RISC OS Ronald <gettingchoppy@gmail.com> - 2018-12-23 14:35 +1300
                Re: A GnuTLS-Problem - problems fetchin emails using RISC OS druck <news@druck.org.uk> - 2018-12-23 14:22 +0000
                Re: A GnuTLS-Problem - problems fetchin emails using RISC OS news@sprow.co.uk - 2018-12-23 12:56 -0800
                Re: A GnuTLS-Problem - problems fetchin emails using RISC OS Matthew Phillips <spam2011m@yahoo.co.uk> - 2018-12-28 20:28 +0000
                Re: A GnuTLS-Problem - problems fetchin emails using RISC OS Ronald <gettingchoppy@gmail.com> - 2018-12-29 12:10 +1300

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