Re: [Qemu-devel] [PATCH 3/3] monitor: add ability to dump SLB entries

[Alexander Graf <agraf@suse.de>]

On 31.10.2011, at 04:16, David Gibson wrote:

> From: Nishanth Aravamudan <nacc@us.ibm.com>
> 
> When run with a PPC Book3S (server) CPU Currently 'info tlb' in the
> qemu monitor reports "dump_mmu: unimplemented".  However, during
> bringup work, it can be quite handy to have the SLB entries, which are
> available in the CPUPPCState.  This patch adds an implementation of
> info tlb for book3s, which dumps the SLB.
> 
> Signed-off-by: Nishanth Aravamudan <nacc@us.ibm.com>
> Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
> ---
> target-ppc/helper.c |   32 +++++++++++++++++++++++++++-----
> 1 files changed, 27 insertions(+), 5 deletions(-)
> 
> diff --git a/target-ppc/helper.c b/target-ppc/helper.c
> index 137a494..29c7050 100644
> --- a/target-ppc/helper.c
> +++ b/target-ppc/helper.c
> @@ -1545,14 +1545,36 @@ static void mmubooke206_dump_mmu(FILE *f, fprintf_function cpu_fprintf,
>     }
> }
> 
> +static void mmubooks_dump_mmu(FILE *f, fprintf_function cpu_fprintf,
> +                              CPUState *env)
> +{
> +    int i;
> +    uint64_t slbe, slbv;
> +
> +    cpu_synchronize_state(env);
> +
> +    cpu_fprintf(f, "SLB\tESID\t\t\tVSID\n");
> +    for (i = 0; i < env->slb_nr; i++) {
> +        slbe = env->slb[i].esid;
> +        slbv = env->slb[i].vsid;

From cpu.h:

#if defined(TARGET_PPC64)
    /* Address space register */
    target_ulong asr;
    /* PowerPC 64 SLB area */
    ppc_slb_t slb[64];
    int slb_nr;
#endif


> +        if (slbe == 0 && slbv == 0) {
> +            continue;
> +        }
> +        cpu_fprintf(f, "%d\t0x%016" PRIx64 "\t0x%016" PRIx64 "\n",
> +                    i, slbe, slbv);
> +    }
> +}
> +
> void dump_mmu(FILE *f, fprintf_function cpu_fprintf, CPUState *env)
> {
> -    switch (env->mmu_model) {
> -    case POWERPC_MMU_BOOKE206:
> +    if (env->mmu_model == POWERPC_MMU_BOOKE206) {
>         mmubooke206_dump_mmu(f, cpu_fprintf, env);
> -        break;
> -    default:
> -        cpu_fprintf(f, "%s: unimplemented\n", __func__);
> +    } else {
> +        if ((env->mmu_model & POWERPC_MMU_64B) != 0) {

I would actually prefer to explicitly keep the switch and match on all implementations explicitly. Also, have you verified this works without CONFIG_PPC64 set? In cpu.h I see the following:

#if defined(TARGET_PPC64)
#define POWERPC_MMU_64       0x00010000
#define POWERPC_MMU_1TSEG    0x00020000
    /* 64 bits PowerPC MMU                                     */
    POWERPC_MMU_64B        = POWERPC_MMU_64 | 0x00000001,
    /* 620 variant (no segment exceptions)                     */
    POWERPC_MMU_620        = POWERPC_MMU_64 | 0x00000002,
    /* Architecture 2.06 variant                               */
    POWERPC_MMU_2_06       = POWERPC_MMU_64 | POWERPC_MMU_1TSEG | 0x00000003,
#endif /* defined(TARGET_PPC64) */

So POWERPC_MMU_64B shouldn't be defined for qemu-system-ppc.


Alex