On 03/12/2019 14:44, Alexey Kardashevskiy wrote:
>
>
> On 29/11/2019 12:35, David Gibson wrote:
>> Move the calculation of the Real Mode Area (RMA) size into a helper
>> function. While we're there clean it up and correct it in a few ways:
>> * Add comments making it clearer where the various constraints come from
>> * Remove a pointless check that the RMA fits within Node 0 (we've just
>> clamped it so that it does)
>> * The 16GiB limit we apply is only correct for POWER8, but there is also
>> a 1TiB limit that applies on POWER9.
>>
>> Signed-off-by: David Gibson <da...@gibson.dropbear.id.au>
>> ---
>> hw/ppc/spapr.c | 57 +++++++++++++++++++++++++++++++-------------------
>> 1 file changed, 35 insertions(+), 22 deletions(-)
>>
>> diff --git a/hw/ppc/spapr.c b/hw/ppc/spapr.c
>> index 52c39daa99..7efd4f2b85 100644
>> --- a/hw/ppc/spapr.c
>> +++ b/hw/ppc/spapr.c
>> @@ -2664,6 +2664,40 @@ static PCIHostState *spapr_create_default_phb(void)
>> return PCI_HOST_BRIDGE(dev);
>> }
>>
>> +static hwaddr spapr_rma_size(SpaprMachineState *spapr, Error **errp)
>> +{
>> + MachineState *machine = MACHINE(spapr);
>> + hwaddr rma_size = machine->ram_size;
>> + hwaddr node0_size = spapr_node0_size(machine);
>> +
>> + /* RMA has to fit in the first NUMA node */
>> + rma_size = MIN(rma_size, node0_size);
>> +
>> + /*
>> + * VRMA access is via a special 1TiB SLB mapping, so the RMA can
>> + * never exceed that
>> + */
>> + rma_size = MIN(rma_size, TiB);
>> +
>> + /*
>> + * RMA size is controlled in hardware by LPCR[RMLS]. On POWER8
>
>
> RMA is controlled by LPCR on P8 but the RMLS bits on P9 are reserved
> (also reserved in PowerISA 3.0).
>
>
>> + * the largest RMA that can be specified there is 16GiB
>
>
> The P8 user manual says:
> ===
> The following RMO sizes are available for the POWER8 processor.
> The RMLS[34:37] field in the LPCR defines the RMO sizes, as described below.
> 1000 - 32 MB
> 0011 - 64 MB
> 0111 - 128 MB
> 0100 - 256 MB
> 0010 - 1 GB
> 0001 - 16 GB
> 0000 - 256 GB
> ===
>
> The maximum seems to be 256GiB.
Ah, update from Paul - we do not actually use what LPCR[RMLS] controls -
Real Mode Offset Register (RMOR).
>
>
>> + */
>> + if (!ppc_type_check_compat(machine->cpu_type, CPU_POWERPC_LOGICAL_3_00,
>> + 0, spapr->max_compat_pvr)) {
>> + rma_size = MIN(rma_size, 16 * GiB);
>> + }
>> +
>> + if (rma_size < (MIN_RMA_SLOF * MiB)) {
>
>
> nit: it is time to redefine MIN_RMA_SLOF to use MiBs imho :)
>
>
>> + error_setg(errp,
>> +"pSeries SLOF firmware requires >= %ldMiB guest RMA (Real Mode Area)",
>> + MIN_RMA_SLOF);
>
> Something went wrong with formatting here.
>
> Otherwise looks good. Thanks,
>
>
>
>> + return -1;
>> + }
>> +
>> + return rma_size;
>> +}
>> +
>> /* pSeries LPAR / sPAPR hardware init */
>> static void spapr_machine_init(MachineState *machine)
>> {
>> @@ -2675,7 +2709,6 @@ static void spapr_machine_init(MachineState *machine)
>> int i;
>> MemoryRegion *sysmem = get_system_memory();
>> MemoryRegion *ram = g_new(MemoryRegion, 1);
>> - hwaddr node0_size = spapr_node0_size(machine);
>> long load_limit, fw_size;
>> char *filename;
>> Error *resize_hpt_err = NULL;
>> @@ -2715,20 +2748,7 @@ static void spapr_machine_init(MachineState *machine)
>> exit(1);
>> }
>>
>> - spapr->rma_size = node0_size;
>> -
>> - /* Actually we don't support unbounded RMA anymore since we added
>> - * proper emulation of HV mode. The max we can get is 16G which
>> - * also happens to be what we configure for PAPR mode so make sure
>> - * we don't do anything bigger than that
>> - */
>> - spapr->rma_size = MIN(spapr->rma_size, 0x400000000ull);
>> -
>> - if (spapr->rma_size > node0_size) {
>> - error_report("Numa node 0 has to span the RMA (%#08"HWADDR_PRIx")",
>> - spapr->rma_size);
>> - exit(1);
>> - }
>> + spapr->rma_size = spapr_rma_size(spapr, &error_fatal);
>>
>> /* Setup a load limit for the ramdisk leaving room for SLOF and FDT */
>> load_limit = MIN(spapr->rma_size, RTAS_MAX_ADDR) - FW_OVERHEAD;
>> @@ -2956,13 +2976,6 @@ static void spapr_machine_init(MachineState *machine)
>> }
>> }
>>
>> - if (spapr->rma_size < (MIN_RMA_SLOF * MiB)) {
>> - error_report(
>> - "pSeries SLOF firmware requires >= %ldM guest RMA (Real Mode
>> Area memory)",
>> - MIN_RMA_SLOF);
>> - exit(1);
>> - }
>> -
>> if (kernel_filename) {
>> uint64_t lowaddr = 0;
>>
>>
>
--
Alexey