On Thu, Jan 24, 2019 at 06:20:02PM +1100, Alexey Kardashevskiy wrote: > > > On 23/01/2019 04:01, Fabiano Rosas wrote: > > These will be used to let GDB know about PPC's Special Purpose > > Registers (SPR). > > > > They take an index based on the order the registers appear in the XML > > file sent by QEMU to GDB. This index does not match the actual > > location of the registers in the env->spr array so the > > gdb_find_spr_idx function does that conversion. > > > > Signed-off-by: Fabiano Rosas <faro...@linux.ibm.com> > > --- > > target/ppc/translate_init.inc.c | 54 ++++++++++++++++++++++++++++++++- > > 1 file changed, 53 insertions(+), 1 deletion(-) > > > > diff --git a/target/ppc/translate_init.inc.c > > b/target/ppc/translate_init.inc.c > > index 710064a25d..f29ac3558a 100644 > > --- a/target/ppc/translate_init.inc.c > > +++ b/target/ppc/translate_init.inc.c > > @@ -9487,6 +9487,55 @@ static bool avr_need_swap(CPUPPCState *env) > > #endif > > } > > > > +#if !defined(CONFIG_USER_ONLY) > > +static int gdb_find_spr_idx(CPUPPCState *env, int n) > > +{ > > + int i; > > + > > + for (i = 0; i < ARRAY_SIZE(env->spr_cb); i++) { > > + ppc_spr_t *spr = &env->spr_cb[i]; > > + > > + if (spr->name && spr->gdb_id == n) { > > + return i; > > + } > > + } > > + return -1; > > +} > > + > > +static int gdb_get_spr_reg(CPUPPCState *env, uint8_t *mem_buf, int n) > > +{ > > + int reg; > > + int len; > > + > > + reg = gdb_find_spr_idx(env, n); > > + if (reg < 0) { > > + return 0; > > + } > > + > > + len = TARGET_LONG_SIZE; > > + stn_p(mem_buf, len, env->spr[reg]); > > + ppc_maybe_bswap_register(env, mem_buf, len); > > > I am confused by this as it produces different results depending on the > guest mode:
Hm, yeah, I thought the bswap here looked odd, but it wasn't obvious to me if it was bogus here, or just a bogus gdb interface we have to work around. > (gdb) p $pvr > $1 = 0x14c0000000000 > (gdb) c > Continuing. > Program received signal SIGINT, Interrupt. > (gdb) p $pvr > $2 = 0x4c0100 But that behaviour definitely looks wrong. > First print is when I stopped the guest in the SLOF firmware (so it is > big-endian) and then I continued and stopped gdb when the guest booted a > little-endian system; the KVM host is little endian, the machine running > gdb is LE too. > > QEMU monitor prints the same 0x4c0100 in both cases. > > I am adding the inventor of maybe_bswap_register() in cc: for > assistance. Swapping happens: > - once for BE: after stn_p() > *(unsigned long *)mem_buf is 0x14c0000000000 > - twice for LE. > > > > > > > + return len; > > +} > > + > > +static int gdb_set_spr_reg(CPUPPCState *env, uint8_t *mem_buf, int n) > > +{ > > + int reg; > > + int len; > > + > > + reg = gdb_find_spr_idx(env, n); > > + if (reg < 0) { > > + return 0; > > + } > > + > > + len = TARGET_LONG_SIZE; > > + ppc_maybe_bswap_register(env, mem_buf, len); > > + env->spr[reg] = ldn_p(mem_buf, len); > > + > > + return len; > > +} > > +#endif > > + > > static int gdb_get_float_reg(CPUPPCState *env, uint8_t *mem_buf, int n) > > { > > if (n < 32) { > > @@ -9716,7 +9765,10 @@ static void ppc_cpu_realize(DeviceState *dev, Error > > **errp) > > gdb_register_coprocessor(cs, gdb_get_vsx_reg, gdb_set_vsx_reg, > > 32, "power-vsx.xml", 0); > > } > > - > > +#ifndef CONFIG_USER_ONLY > > + gdb_register_coprocessor(cs, gdb_get_spr_reg, gdb_set_spr_reg, > > + pcc->gdb_num_sprs, "power-spr.xml", 0); > > +#endif > > qemu_init_vcpu(cs); > > > > pcc->parent_realize(dev, errp); > > > -- David Gibson | I'll have my music baroque, and my code david AT gibson.dropbear.id.au | minimalist, thank you. NOT _the_ _other_ | _way_ _around_! http://www.ozlabs.org/~dgibson
signature.asc
Description: PGP signature