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

[Igor Mammedov]

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.

> 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
>