Re: [PATCH 14/14] target/arm: Support reading m-profile system registers from gdb

[Richard Henderson]

On 2/20/23 06:02, Peter Maydell wrote:
> > +    /*
> > +     * NOTE: MSP, PSP, MSPLIM, PSPLIM technically don't exist if the
> > +     * secure extension is present (replaced by MSP_S, MSP_NS, et al).
> > +     * However, the MRS instruction is still allowed to read from MSP and PSP,
> > +     * and will return the value associated with the current security state.
>
> What's "don't exist" based on here? Architecturally MSPLIM, PSPLIM etc
> are banked registers; MRS/MSR let you access the one for the current
> security state, and (if you are Secure) the one for the NS state.

Copied that wording from David.

> > +    g_string_printf(s, "<?xml version=\"1.0\"?>");
> > +    g_string_append_printf(s, "<!DOCTYPE target SYSTEM \"gdb-target.dtd\">");
> > +    g_string_append_printf(s, "<feature name=\"org.gnu.gdb.arm.m-system\">\n");
>
> Half of these need to be in org.gnu.gdb.arm.secext.
> These aren't our own XML features we're making up (if they
> were then they would be in org.qemu.something), so we should
> follow the existing precedent about what registers go in them.

Now that you point it out (and I should have checked myself), we are kinda making them up. 
 The only registers within upstream gdb m-system and secext are MSP, PSP, MSP_NS, MSP_S, 
PSP_NS, PSP_S.  All the others are our own addition.

Should all the rest be in a third bit of xml?


r~