[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re: [Qemu-devel] [Qemu-ppc] [PATCH v4 2/3] target/ppc: Add GDB callbacks
From: |
Alexey Kardashevskiy |
Subject: |
Re: [Qemu-devel] [Qemu-ppc] [PATCH v4 2/3] target/ppc: Add GDB callbacks for SPRs |
Date: |
Thu, 24 Jan 2019 18:20:02 +1100 |
User-agent: |
Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.4.0 |
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 <address@hidden>
> ---
> 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:
(gdb) p $pvr
$1 = 0x14c0000000000
(gdb) c
Continuing.
Program received signal SIGINT, Interrupt.
(gdb) p $pvr
$2 = 0x4c0100
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);
>
--
Alexey
- [Qemu-devel] [PATCH v4 0/3] ppc/gdbstub: Expose SPRs to GDB, Fabiano Rosas, 2019/01/22
- [Qemu-devel] [PATCH v4 1/3] target/ppc: Add SPRs XML generation code for gdbstub, Fabiano Rosas, 2019/01/22
- [Qemu-devel] [PATCH v4 2/3] target/ppc: Add GDB callbacks for SPRs, Fabiano Rosas, 2019/01/22
- Re: [Qemu-devel] [Qemu-ppc] [PATCH v4 2/3] target/ppc: Add GDB callbacks for SPRs,
Alexey Kardashevskiy <=
- Re: [Qemu-devel] [Qemu-ppc] [PATCH v4 2/3] target/ppc: Add GDB callbacks for SPRs, David Gibson, 2019/01/26
- Re: [Qemu-devel] [Qemu-ppc] [PATCH v4 2/3] target/ppc: Add GDB callbacks for SPRs, Fabiano Rosas, 2019/01/28
- Re: [Qemu-devel] [Qemu-ppc] [PATCH v4 2/3] target/ppc: Add GDB callbacks for SPRs, Alexey Kardashevskiy, 2019/01/28
- Re: [Qemu-devel] [Qemu-ppc] [PATCH v4 2/3] target/ppc: Add GDB callbacks for SPRs, Fabiano Rosas, 2019/01/30
- Re: [Qemu-devel] [Qemu-ppc] [PATCH v4 2/3] target/ppc: Add GDB callbacks for SPRs, Alexey Kardashevskiy, 2019/01/31
- Re: [Qemu-devel] [Qemu-ppc] [PATCH v4 2/3] target/ppc: Add GDB callbacks for SPRs, Fabiano Rosas, 2019/01/31
- Re: [Qemu-devel] [Qemu-ppc] [PATCH v4 2/3] target/ppc: Add GDB callbacks for SPRs, Alexey Kardashevskiy, 2019/01/31
[Qemu-devel] [PATCH v4 3/3] target/ppc: Enable reporting of SPRs to GDB, Fabiano Rosas, 2019/01/22