Set the TIR default value with the SMT thread index, and place some standard limits on SMT configurations. Now powernv is able to boot skiboot and Linux with a SMT topology, including booting a KVM guest.
There are several other per-core SPRs, but they are not so important to run OPAL/Linux. Some important per-LPAR ones to convert before powernv could run in 1LPAR mode. Broadcast msgsnd is not yet implemented either, but skiboot/Linux does not use that. KVM uses an implementation-specific detail of POWER9/10 TLBs where TLBIEL invalidates translations of all threads on a core, but that is not required here because KVM does not cache translations across PID or LPID switch. Most of these I have or aren't too hard to implement, but I start with a small bare bones for comments. Not-yet-Signed-off-by: Nicholas Piggin <[email protected]> --- hw/ppc/pnv.c | 12 ++++++++++++ hw/ppc/pnv_core.c | 13 +++++-------- 2 files changed, 17 insertions(+), 8 deletions(-) diff --git a/hw/ppc/pnv.c b/hw/ppc/pnv.c index fc083173f3..f599ccad1d 100644 --- a/hw/ppc/pnv.c +++ b/hw/ppc/pnv.c @@ -887,6 +887,18 @@ static void pnv_init(MachineState *machine) pnv->num_chips = machine->smp.max_cpus / (machine->smp.cores * machine->smp.threads); + + if (machine->smp.threads > 8) { + error_report("Cannot support more than 8 threads/core " + "on a powernv machine"); + exit(1); + } + if (!is_power_of_2(machine->smp.threads)) { + error_report("Cannot support %d threads/core on a powernv" + "machine because it must be a power of 2", + machine->smp.threads); + exit(1); + } /* * TODO: should we decide on how many chips we can create based * on #cores and Venice vs. Murano vs. Naples chip type etc..., diff --git a/hw/ppc/pnv_core.c b/hw/ppc/pnv_core.c index 0bc3ad41c8..acd83caee8 100644 --- a/hw/ppc/pnv_core.c +++ b/hw/ppc/pnv_core.c @@ -167,12 +167,13 @@ static const MemoryRegionOps pnv_core_power9_xscom_ops = { .endianness = DEVICE_BIG_ENDIAN, }; -static void pnv_core_cpu_realize(PnvCore *pc, PowerPCCPU *cpu, Error **errp) +static void pnv_core_cpu_realize(PnvCore *pc, PowerPCCPU *cpu, Error **errp, + int thread_index) { CPUPPCState *env = &cpu->env; int core_pir; - int thread_index = 0; /* TODO: TCG supports only one thread */ ppc_spr_t *pir = &env->spr_cb[SPR_PIR]; + ppc_spr_t *tir = &env->spr_cb[SPR_TIR]; Error *local_err = NULL; PnvChipClass *pcc = PNV_CHIP_GET_CLASS(pc->chip); @@ -188,11 +189,7 @@ static void pnv_core_cpu_realize(PnvCore *pc, PowerPCCPU *cpu, Error **errp) core_pir = object_property_get_uint(OBJECT(pc), "pir", &error_abort); - /* - * The PIR of a thread is the core PIR + the thread index. We will - * need to find a way to get the thread index when TCG supports - * more than 1. We could use the object name ? - */ + tir->default_value = thread_index; pir->default_value = core_pir + thread_index; /* Set time-base frequency to 512 MHz */ @@ -241,7 +238,7 @@ static void pnv_core_realize(DeviceState *dev, Error **errp) } for (j = 0; j < cc->nr_threads; j++) { - pnv_core_cpu_realize(pc, pc->threads[j], &local_err); + pnv_core_cpu_realize(pc, pc->threads[j], &local_err, j); if (local_err) { goto err; } -- 2.40.1
