Re: [PATCH v5 09/11] piix4: don't reserve hw resources when hotplug is off globally

[Ani Sinha]

On Thu, Sep 17, 2020 at 11:46 AM Igor Mammedov <imammedo@redhat.com> wrote:
>
> On Wed, 16 Sep 2020 13:49:08 +0530
> Ani Sinha <ani@anisinha.ca> wrote:
>
> > When acpi hotplug is turned off for both root pci bus as well as for pci
> > bridges, we should not generate the related acpi code for DSDT table or
> > initialize related hw ports or reserve hw resources. This change makes
> > sure all those operations are turned off in the case acpi pci hotplug is
> > off globally.
> >
> > In this change, we also make sure AMLs for the PCNT method are only added 
> > when
> > bsel is enabled for the corresponding pci bus or bridge hotplug is turned 
> > on.
> > As a result, when the hotplug for both the root pci device and bridge are
> > disabled, this AML in the DSDT acpi table is turned off.
> >
> > As q35 machines do not use bsel for it's pci buses at this point in time, 
> > this
> > change affects DSDT acpi table for q35 machines as well. Therefore, we also
> > commit the updated golden master DSDT table acpi binary blobs as well.
>
> Please split binary blobs into separate patch, as described in process.
> Otherwise the patch is very likely to become un-merge-able due to conflicts.

I wanted to make sure that the changes in this patch and the blobs go
together as a single atomic commit since the unit test will break if
one has the patch but not the blobs.

>
> > Following is a typical diff between the q35 acpi DSDT table blobs:
> >
> > @@ -1,30 +1,30 @@
> >  /*
> >   * Intel ACPI Component Architecture
> >   * AML/ASL+ Disassembler version 20180105 (64-bit version)
> >   * Copyright (c) 2000 - 2018 Intel Corporation
> >   *
> >   * Disassembling to symbolic ASL+ operators
> >   *
> > - * Disassembly of tests/data/acpi/q35/DSDT, Tue Sep 15 18:52:47 2020
> > + * Disassembly of /tmp/aml-3O0DR0, Tue Sep 15 18:52:47 2020
> >   *
> >   * Original Table Header:
> >   *     Signature        "DSDT"
> > - *     Length           0x00001DFE (7678)
> > + *     Length           0x00001DF6 (7670)
> >   *     Revision         0x01 **** 32-bit table (V1), no 64-bit math support
> > - *     Checksum         0xAC
> > + *     Checksum         0x17
> >   *     OEM ID           "BOCHS "
> >   *     OEM Table ID     "BXPCDSDT"
> >   *     OEM Revision     0x00000001 (1)
> >   *     Compiler ID      "BXPC"
> >   *     Compiler Version 0x00000001 (1)
> >   */
> >  DefinitionBlock ("", "DSDT", 1, "BOCHS ", "BXPCDSDT", 0x00000001)
> >  {
> >      Scope (\)
> >      {
> >          OperationRegion (DBG, SystemIO, 0x0402, One)
> >          Field (DBG, ByteAcc, NoLock, Preserve)
> >          {
> >              DBGB,   8
> >          }
> >
> > @@ -3113,24 +3113,20 @@
> >                  Name (_ADR, 0x00010000)  // _ADR: Address
> >                  Method (_S1D, 0, NotSerialized)  // _S1D: S1 Device State
> >                  {
> >                      Return (Zero)
> >                  }
> >
> >                  Method (_S2D, 0, NotSerialized)  // _S2D: S2 Device State
> >                  {
> >                      Return (Zero)
> >                  }
> >
> >                  Method (_S3D, 0, NotSerialized)  // _S3D: S3 Device State
> >                  {
> >                      Return (Zero)
> >                  }
> >              }
> > -
> > -            Method (PCNT, 0, NotSerialized)
> > -            {
> > -            }
> >          }
> >      }
> >  }
> >
> > Signed-off-by: Ani Sinha <ani@anisinha.ca>
> > ---
> >  hw/acpi/piix4.c                   |   6 ++++--
> >  hw/i386/acpi-build.c              |  25 ++++++++++++++++++-------
> >  tests/data/acpi/q35/DSDT          | Bin 7678 -> 7670 bytes
> >  tests/data/acpi/q35/DSDT.acpihmat | Bin 9002 -> 8994 bytes
> >  tests/data/acpi/q35/DSDT.bridge   | Bin 7695 -> 7688 bytes
> >  tests/data/acpi/q35/DSDT.cphp     | Bin 8141 -> 8133 bytes
> >  tests/data/acpi/q35/DSDT.dimmpxm  | Bin 9331 -> 9323 bytes
> >  tests/data/acpi/q35/DSDT.ipmibt   | Bin 7753 -> 7745 bytes
> >  tests/data/acpi/q35/DSDT.memhp    | Bin 9037 -> 9029 bytes
> >  tests/data/acpi/q35/DSDT.mmio64   | Bin 8808 -> 8801 bytes
> >  tests/data/acpi/q35/DSDT.numamem  | Bin 7684 -> 7676 bytes
> >  tests/data/acpi/q35/DSDT.tis      | Bin 8283 -> 8276 bytes
> >  12 files changed, 22 insertions(+), 9 deletions(-)
> >
> > diff --git a/hw/acpi/piix4.c b/hw/acpi/piix4.c
> > index e6163bb6ce..b70b1f98af 100644
> > --- a/hw/acpi/piix4.c
> > +++ b/hw/acpi/piix4.c
> > @@ -596,8 +596,10 @@ static void 
> > piix4_acpi_system_hot_add_init(MemoryRegion *parent,
> >                            "acpi-gpe0", GPE_LEN);
> >      memory_region_add_subregion(parent, GPE_BASE, &s->io_gpe);
> >
> > -    acpi_pcihp_init(OBJECT(s), &s->acpi_pci_hotplug, bus, parent,
> > -                    s->use_acpi_hotplug_bridge);
> > +    if (s->use_acpi_hotplug_bridge || s->use_acpi_root_pci_hotplug) {
> > +        acpi_pcihp_init(OBJECT(s), &s->acpi_pci_hotplug, bus, parent,
> > +                        s->use_acpi_hotplug_bridge);
> > +    }
> >
> >      s->cpu_hotplug_legacy = true;
> >      object_property_add_bool(OBJECT(s), "cpu-hotplug-legacy",
> > diff --git a/hw/i386/acpi-build.c b/hw/i386/acpi-build.c
> > index e079b686f5..e41bb0992b 100644
> > --- a/hw/i386/acpi-build.c
> > +++ b/hw/i386/acpi-build.c
> > @@ -95,6 +95,7 @@ typedef struct AcpiPmInfo {
> >      bool s3_disabled;
> >      bool s4_disabled;
> >      bool pcihp_bridge_en;
> > +    bool pcihp_root_en;
> >      uint8_t s4_val;
> >      AcpiFadtData fadt;
> >      uint16_t cpu_hp_io_base;
> > @@ -245,6 +246,9 @@ static void acpi_get_pm_info(MachineState *machine, 
> > AcpiPmInfo *pm)
> >      pm->pcihp_bridge_en =
> >          object_property_get_bool(obj, 
> > "acpi-pci-hotplug-with-bridge-support",
> >                                   NULL);
> > +    pm->pcihp_root_en =
> > +        object_property_get_bool(obj, "acpi-root-pci-hotplug",
> > +                                 NULL);
> >  }
> >
> >  static void acpi_get_misc_info(AcpiMiscInfo *info)
> > @@ -450,10 +454,12 @@ static void build_append_pci_bus_devices(Aml 
> > *parent_scope, PCIBus *bus,
> >      }
> >
> >      /* Append PCNT method to notify about events on local and child buses.
> > -     * Add unconditionally for root since DSDT expects it.
> > +     * Add this method for root bus only when hotplug is enabled since DSDT
> > +     * expects it.
> >       */
> > -    method = aml_method("PCNT", 0, AML_NOTSERIALIZED);
> > -
> > +    if (bsel || pcihp_bridge_en) {
> > +        method = aml_method("PCNT", 0, AML_NOTSERIALIZED);
> > +    }
> >      /* If bus supports hotplug select it and notify about local events */
> >      if (bsel) {
> >          uint64_t bsel_val = qnum_get_uint(qobject_to(QNum, bsel));
> > @@ -479,7 +485,10 @@ static void build_append_pci_bus_devices(Aml 
> > *parent_scope, PCIBus *bus,
> >              aml_append(method, aml_name("^S%.02X.PCNT", devfn));
> >          }
> >      }
> > -    aml_append(parent_scope, method);
> > +
> > +    if (bsel || pcihp_bridge_en) {
> > +        aml_append(parent_scope, method);
> > +    }
> >      qobject_unref(bsel);
> >  }
> >
> > @@ -1504,7 +1513,9 @@ build_dsdt(GArray *table_data, BIOSLinker *linker,
> >          build_hpet_aml(dsdt);
> >          build_piix4_isa_bridge(dsdt);
> >          build_isa_devices_aml(dsdt);
> > -        build_piix4_pci_hotplug(dsdt);
> > +        if (pm->pcihp_bridge_en || pm->pcihp_root_en) {
> > +            build_piix4_pci_hotplug(dsdt);
> > +        }
> >          build_piix4_pci0_int(dsdt);
> >      } else {
> >          sb_scope = aml_scope("_SB");
> > @@ -1546,7 +1557,7 @@ build_dsdt(GArray *table_data, BIOSLinker *linker,
> >      {
> >          aml_append(scope, aml_name_decl("_HID", aml_string("ACPI0006")));
> >
> > -        if (misc->is_piix4) {
> > +        if (misc->is_piix4 && (pm->pcihp_bridge_en || pm->pcihp_root_en)) {
> >              method = aml_method("_E01", 0, AML_NOTSERIALIZED);
> >              aml_append(method,
> >                  aml_acquire(aml_name("\\_SB.PCI0.BLCK"), 0xFFFF));
> > @@ -1698,7 +1709,7 @@ build_dsdt(GArray *table_data, BIOSLinker *linker,
> >      crs_range_set_free(&crs_range_set);
> >
> >      /* reserve PCIHP resources */
> > -    if (pm->pcihp_io_len) {
> > +    if (pm->pcihp_io_len && (pm->pcihp_bridge_en || pm->pcihp_root_en)) {
> >          dev = aml_device("PHPR");
> >          aml_append(dev, aml_name_decl("_HID", aml_string("PNP0A06")));
> >          aml_append(dev,
> > diff --git a/tests/data/acpi/q35/DSDT b/tests/data/acpi/q35/DSDT
> > index 
> > bba8884073a27427b88ac0d733c9c87330a59366..4fad91b72e279b744b0528fd687c862d3a3d5cfa
> >  100644
> > GIT binary patch
> > delta 33
> > pcmexo{mq)oCD<k8n=AtZqxeRyWwM-ZEHUxHPVoYElXuD50sy=Q3Pb<^
> >
> > delta 42
> > ycmexn{m+`qCD<k8pDY6d<C=|J%VfFySYqOXo#F-DSSIh3wPhD!3vl)eVE_Owj0{Tv
> >
> > diff --git a/tests/data/acpi/q35/DSDT.acpihmat 
> > b/tests/data/acpi/q35/DSDT.acpihmat
> > index 
> > 9cac92418b5fcc2767dc74603d599642b59623fe..e4df7d1ca89578dd81be3539c8f83f073bb8db25
> >  100644
> > GIT binary patch
> > delta 33
> > pcmZ4Gw#bdkCD<iINtuCx@ySN6OG=z>EHUxHPVoYElb<Qs0syHh3KIYT
> >
> > delta 42
> > xcmZ4Fw#tpmCD<iIOPPUzv2r8VB_%FDmYDcpr+5K3mdQ_*Y}rNF0-XIq7y$jZ3mO0b
> >
> > diff --git a/tests/data/acpi/q35/DSDT.bridge 
> > b/tests/data/acpi/q35/DSDT.bridge
> > index 
> > f08b7245f59aad491fcaa60e2bab1085c369ea1c..065399174575442201cc09ffa4939ddf90ac81b4
> >  100644
> > GIT binary patch
> > delta 33
> > ocmeCT>9FB)33dtLkYiwAT)&ZPnJlLVYfOBwQ@nt~<ejqq0G06xDgXcg
> >
> > delta 41
> > wcmeCM>9^r>33dtLmt$aH^xnv|OqSE1H6}jTDPF*R@=jTQb`iD!XTJ~z0NaZSF#rGn
> >
> > diff --git a/tests/data/acpi/q35/DSDT.cphp b/tests/data/acpi/q35/DSDT.cphp
> > index 
> > 57d859cef9fa16a8f125c4b338611c8472699f38..8d2395e3cb4383b30e3840caed0d09ccad0c7323
> >  100644
> > GIT binary patch
> > delta 33
> > ocmX?Wf7G7KCD<k8s5}D$<AjY|rShC^EHUxHPVoYElRM>Y0kO^r)&Kwi
> >
> > delta 42
> > xcmX?Vf7YJMCD<k8tULn)qv}SkQh6>vmYDcpr+5K3mdPFRw(KHo0nUCQ3;+bB3f%wz
> >
> > diff --git a/tests/data/acpi/q35/DSDT.dimmpxm 
> > b/tests/data/acpi/q35/DSDT.dimmpxm
> > index 
> > 9d5bd5744e2ba2e0f6126c3aba0bb36af865e499..df7422051c6feadeaa3b6733ad7efa67c339b49d
> >  100644
> > GIT binary patch
> > delta 33
> > ocmezD@!EsSCD<h-TZMsvF>)i9v<jyiOH6#QQ@nuPWPKG|0ILxQ{r~^~
> >
> > delta 42
> > xcmaFu@!5mRCD<jTScQRs@!du)X%#L%mYDcpr+5K3mdSc5w(KHo0nUCQ3;+_P3k3iG
> >
> > diff --git a/tests/data/acpi/q35/DSDT.ipmibt 
> > b/tests/data/acpi/q35/DSDT.ipmibt
> > index 
> > 5cd11de6a8fe47324e5f922823a22746882f19f5..c4ce5cc0ede822ea82656d078d7a8b7eee4a7516
> >  100644
> > GIT binary patch
> > delta 33
> > ocmX?UbI^v%CD<jzQI3Iu(Q6~uM_EocmYDcpr+5Lo$*gj=0Hl8i@&Et;
> >
> > delta 42
> > xcmX?TbJB*(CD<jzQ;vaw@%~1xkFs2TEHUxHPVoY6ER$K}Y}rNF0-XIq7yt{`3i$v4
> >
> > diff --git a/tests/data/acpi/q35/DSDT.memhp b/tests/data/acpi/q35/DSDT.memhp
> > index 
> > 05a7a73ec43130d5c3018bb462fd84981bfb151c..84614ffc1452358053b4c2be4b2edcb4d56a9ae6
> >  100644
> > GIT binary patch
> > delta 33
> > ocmX@>cGQi_CD<jzRhfZ-kz*s*S0zq2mYDcpr+5Lo$(+iz0Hk>c=Kufz
> >
> > delta 42
> > xcmX@=cGiu{CD<jzSDAr<aqdR0uS#5gEHUxHPVoY6ER#8uZP`WG0-XIq7yt`p3hn>^
> >
> > diff --git a/tests/data/acpi/q35/DSDT.mmio64 
> > b/tests/data/acpi/q35/DSDT.mmio64
> > index 
> > efd3f1188f2b55da1514212d4be081a61c2a96e9..d8dd702b69cc24a6b58b8eaa79ea02439a2a7dd9
> >  100644
> > GIT binary patch
> > delta 33
> > ocmaFi^3a9LCD<h-QHg<paqmX1|B9R*tTFMyPVoW`lZBN00lUBo5&!@I
> >
> > delta 41
> > wcmaFp^1_A7CD<h-Ly3WbF>)i<e??Az)|mKUr+5MP$wEs0>>_Ld&VC^b00^lI82|tP
> >
> > diff --git a/tests/data/acpi/q35/DSDT.numamem 
> > b/tests/data/acpi/q35/DSDT.numamem
> > index 
> > 1978b55f1255402bf9bade0b91150b5cb49789a4..f36d22063a6eed4fb107ffd0e10477a2d6d7a983
> >  100644
> > GIT binary patch
> > delta 33
> > pcmZp%`D4xH66_N4N0xzs@!&?THL{#;EHUxHPVoYElMl$+0sy+k3XK2&
> >
> > delta 42
> > xcmexk-D1P#66_MfBFDhM7`l;bjVzZROH6#QQ@ns1%jEsCw(KHo0nUCQ3;^@W3X}i<
> >
> > diff --git a/tests/data/acpi/q35/DSDT.tis b/tests/data/acpi/q35/DSDT.tis
> > index 
> > 638de3872673d17b1958497d0e62c83653de1602..203030a61a92c204bb93c43fe79e546471ae2985
> >  100644
> > GIT binary patch
> > delta 38
> > ucmccZaK(YkCD<h-M1g^U@x?~2O|qOGnlbUgPVoW`laI>UZRU~-WC8&31`DbH
> >
> > delta 45
> > zcmccOaNB{)CD<h-T7iLqv1KFICRt8@&6xOLr+5MP$wy`F*hJU@oc%&JGsy)p0RTF+
> > B45<JB
> >
>