[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re: [PATCH v5 04/10] hw/intc: GICv3 ITS Command processing
From: |
Eric Auger |
Subject: |
Re: [PATCH v5 04/10] hw/intc: GICv3 ITS Command processing |
Date: |
Tue, 6 Jul 2021 12:04:27 +0200 |
User-agent: |
Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.10.1 |
Hi Shashi, Peter,
On 7/6/21 5:25 AM, shashi.mallela@linaro.org wrote:
> On Mon, 2021-07-05 at 20:47 -0400, shashi.mallela@linaro.org wrote:
>> On Mon, 2021-07-05 at 15:54 +0100, Peter Maydell wrote:
>>> On Wed, 30 Jun 2021 at 16:32, Shashi Mallela <
>>> shashi.mallela@linaro.org> wrote:
>>>> Added ITS command queue handling for MAPTI,MAPI commands,handled
>>>> ITS
>>>> translation which triggers an LPI via INT command as well as
>>>> write
>>>> to GITS_TRANSLATER register,defined enum to differentiate between
>>>> ITS
>>>> command interrupt trigger and GITS_TRANSLATER based interrupt
>>>> trigger.
>>>> Each of these commands make use of other functionalities
>>>> implemented to
>>>> get device table entry,collection table entry or interrupt
>>>> translation
>>>> table entry required for their processing.
>>>>
>>>> Signed-off-by: Shashi Mallela <shashi.mallela@linaro.org>
>>>> ---
>>>> +static MemTxResult process_mapti(GICv3ITSState *s, uint64_t
>>>> value,
>>>> + uint32_t offset, bool
>>>> ignore_pInt)
>>>> +{
>>>> + AddressSpace *as = &s->gicv3->dma_as;
>>>> + uint32_t devid, eventid;
>>>> + uint32_t pIntid = 0;
>>>> + uint32_t max_eventid, max_Intid;
>>>> + bool dte_valid;
>>>> + MemTxResult res = MEMTX_OK;
>>>> + uint16_t icid = 0;
>>>> + uint64_t dte = 0;
>>>> + IteEntry ite;
>>>> + uint32_t int_spurious = INTID_SPURIOUS;
>>>> + uint64_t idbits;
>>>> +
>>>> + devid = ((value & DEVID_MASK) >> DEVID_SHIFT);
>>>> + offset += NUM_BYTES_IN_DW;
>>>> + value = address_space_ldq_le(as, s->cq.base_addr + offset,
>>>> + MEMTXATTRS_UNSPECIFIED, &res);
>>>> +
>>>> + if (res != MEMTX_OK) {
>>>> + return res;
>>>> + }
>>>> +
>>>> + eventid = (value & EVENTID_MASK);
>>>> +
>>>> + if (!ignore_pInt) {
>>>> + pIntid = ((value & pINTID_MASK) >> pINTID_SHIFT);
>>>> + }
>>>> +
>>>> + offset += NUM_BYTES_IN_DW;
>>>> + value = address_space_ldq_le(as, s->cq.base_addr + offset,
>>>> + MEMTXATTRS_UNSPECIFIED, &res);
>>>> +
>>>> + if (res != MEMTX_OK) {
>>>> + return res;
>>>> + }
>>>> +
>>>> + icid = value & ICID_MASK;
>>>> +
>>>> + dte = get_dte(s, devid, &res);
>>>> +
>>>> + if (res != MEMTX_OK) {
>>>> + return res;
>>>> + }
>>>> + dte_valid = dte & TABLE_ENTRY_VALID_MASK;
>>>> +
>>>> + max_eventid = (1UL << (((dte >> 1U) & SIZE_MASK) + 1));
>>>> +
>>>> + if (!ignore_pInt) {
>>>> + idbits = MIN(FIELD_EX64(s->gicv3->cpu->gicr_propbaser,
>>>> GICR_PROPBASER,
>>>> + IDBITS), GICD_TYPER_IDBITS);
>>>
>>> I missed this the first time around, but I don't think this is
>>> right.
>>> Different CPUs could have different GICR_PROPBASER values, so
>>> checking
>>> against just one of them is wrong.
"5.1.1 LPI configuration tables" says
"
It is IMPLEMENTATION DEFINED whether GICR_PROPBASER can be set to
different values on different
Redistributors. GICR_TYPER.CommonLPIAff indicates which Redistributors
must have GICR_PROPBASER set
to the same value whenever GICR_CTLR.EnableLPIs == 1.
"
So we can choose to set CommonLPIAff to 0 if we do not need to emulate
everything. This is what KVM does
Thanks
Eric
The pseudocode only tests
>>> LPIOutOfRange()
>>> which is documented as testing "larger than GICD_TYPER.IDbits or
>>> not
>>> in
>>> the LPI range and not 1023". So I don't think we should be looking
>>> at the GICR_PROPBASER field here.
>>>
>>> More generally, "s->gicv3->cpu->something" is usually going to be
>>> wrong, because it is implicitly looking at CPU 0; often either
>>> there
>>> should be something else telling is which CPU to use (as in
>>> &s->gicv3->cpu[rdbase] where the CTE told us which redistributor),
>>> or we might need to operate on all CPUs/redistributors. The only
>>> exception is where we can guarantee that all the CPUs are the same
>>> (eg when looking at GICR_TYPER.PLPIS.)
>> In that case,the validation of IDBITS(in case of ITS enabled) could
>> be
>> done during the write of gicr_propbaser register value itself(in
>> arm_gicv3_redist.c) and the its command processing code here can just
>> extract the idbits for its use.
>>> thanks
>>> -- PMM
> Hi Peter
>
> Please ignore my last comment.
>
> To address this scenario,i think the feasible option would be to call
> get_cte() to get the rdbase corresponding to icid value passed to mapti
> command.Since each icid is mapped to a rdbase(by virtue of calling MAPC
> command),if the collection table has a valid mapping for this icid we
> continue processing this MAPTI command using &s->gicv3->cpu[rdbase]
> applicable propbaser value to validate idbits, else return without
> further processing.
>
> Thanks
> Shashi
>
>
- Re: [PATCH v5 04/10] hw/intc: GICv3 ITS Command processing, Peter Maydell, 2021/07/05
- Re: [PATCH v5 04/10] hw/intc: GICv3 ITS Command processing, Peter Maydell, 2021/07/05
- Re: [PATCH v5 04/10] hw/intc: GICv3 ITS Command processing, shashi . mallela, 2021/07/05
- Re: [PATCH v5 04/10] hw/intc: GICv3 ITS Command processing, shashi . mallela, 2021/07/05
- Re: [PATCH v5 04/10] hw/intc: GICv3 ITS Command processing, Peter Maydell, 2021/07/06
- Re: [PATCH v5 04/10] hw/intc: GICv3 ITS Command processing, shashi . mallela, 2021/07/06
- Re: [PATCH v5 04/10] hw/intc: GICv3 ITS Command processing, Peter Maydell, 2021/07/06
- Re: [PATCH v5 04/10] hw/intc: GICv3 ITS Command processing, shashi . mallela, 2021/07/06
- Re: [PATCH v5 04/10] hw/intc: GICv3 ITS Command processing,
Eric Auger <=
- Re: [PATCH v5 04/10] hw/intc: GICv3 ITS Command processing, Peter Maydell, 2021/07/06
Re: [PATCH v5 04/10] hw/intc: GICv3 ITS Command processing, Eric Auger, 2021/07/06