hw/acpi: Rename and move build_x86_acpi_pci_hotplug to pcihp

We plan to reuse build_x86_acpi_pci_hotplug() implementation
for ARM so let's move the code to generic pcihp.

Associated static aml_pci_pdsm() helper is also moved along.
build_x86_acpi_pci_hotplug is renamed into build_acpi_pci_hotplug().

No code change intended.

Also fix the reference to acpi_pci_hotplug.rst documentation

Signed-off-by: Eric Auger <eric.auger@redhat.com>
Reviewed-by: Gustavo Romero <gustavo.romero@linaro.org>
Reviewed-by: Igor Mammedov <imammedo@redhat.com>
Reviewed-by: Jonathan Cameron <jonathan.cameron@huawei.com>
Message-Id: <20250714080639.2525563-3-eric.auger@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

1 files changed, 173 insertions, 1 deletions

diff --git a/hw/acpi/pcihp.c b/hw/acpi/pcihp.c
index 497281ae20..cbe7e01385 100644
--- a/hw/acpi/pcihp.c
+++ b/hw/acpi/pcihp.c
@@ -26,7 +26,7 @@
 
 #include "qemu/osdep.h"
 #include "hw/acpi/pcihp.h"
-
+#include "hw/acpi/aml-build.h"
 #include "hw/pci-host/i440fx.h"
 #include "hw/pci/pci.h"
 #include "hw/pci/pci_bridge.h"
@@ -513,6 +513,178 @@ void acpi_pcihp_init(Object *owner, AcpiPciHpState *s, PCIBus *root_bus,
                                    OBJ_PROP_FLAG_READ);
 }
 
+void build_append_pci_dsm_func0_common(Aml *ctx, Aml *retvar)
+{
+    Aml *UUID, *ifctx1;
+    uint8_t byte_list[1] = { 0 }; /* nothing supported yet */
+
+    aml_append(ctx, aml_store(aml_buffer(1, byte_list), retvar));
+    /*
+     * PCI Firmware Specification 3.1
+     * 4.6.  _DSM Definitions for PCI
+     */
+    UUID = aml_touuid("E5C937D0-3553-4D7A-9117-EA4D19C3434D");
+    ifctx1 = aml_if(aml_lnot(aml_equal(aml_arg(0), UUID)));
+    {
+        /* call is for unsupported UUID, bail out */
+        aml_append(ifctx1, aml_return(retvar));
+    }
+    aml_append(ctx, ifctx1);
+
+    ifctx1 = aml_if(aml_lless(aml_arg(1), aml_int(2)));
+    {
+        /* call is for unsupported REV, bail out */
+        aml_append(ifctx1, aml_return(retvar));
+    }
+    aml_append(ctx, ifctx1);
+}
+
+static Aml *aml_pci_pdsm(void)
+{
+    Aml *method, *ifctx, *ifctx1;
+    Aml *ret = aml_local(0);
+    Aml *caps = aml_local(1);
+    Aml *acpi_index = aml_local(2);
+    Aml *zero = aml_int(0);
+    Aml *one = aml_int(1);
+    Aml *not_supp = aml_int(0xFFFFFFFF);
+    Aml *func = aml_arg(2);
+    Aml *params = aml_arg(4);
+    Aml *bnum = aml_derefof(aml_index(params, aml_int(0)));
+    Aml *sunum = aml_derefof(aml_index(params, aml_int(1)));
+
+    method = aml_method("PDSM", 5, AML_SERIALIZED);
+
+    /* get supported functions */
+    ifctx = aml_if(aml_equal(func, zero));
+    {
+        build_append_pci_dsm_func0_common(ifctx, ret);
+
+        aml_append(ifctx, aml_store(zero, caps));
+        aml_append(ifctx,
+            aml_store(aml_call2("AIDX", bnum, sunum), acpi_index));
+        /*
+         * advertise function 7 if device has acpi-index
+         * acpi_index values:
+         *            0: not present (default value)
+         *     FFFFFFFF: not supported (old QEMU without PIDX reg)
+         *        other: device's acpi-index
+         */
+        ifctx1 = aml_if(aml_lnot(
+                     aml_or(aml_equal(acpi_index, zero),
+                            aml_equal(acpi_index, not_supp), NULL)
+                 ));
+        {
+            /* have supported functions */
+            aml_append(ifctx1, aml_or(caps, one, caps));
+            /* support for function 7 */
+            aml_append(ifctx1,
+                aml_or(caps, aml_shiftleft(one, aml_int(7)), caps));
+        }
+        aml_append(ifctx, ifctx1);
+
+        aml_append(ifctx, aml_store(caps, aml_index(ret, zero)));
+        aml_append(ifctx, aml_return(ret));
+    }
+    aml_append(method, ifctx);
+
+    /* handle specific functions requests */
+    /*
+     * PCI Firmware Specification 3.1
+     * 4.6.7. _DSM for Naming a PCI or PCI Express Device Under
+     *        Operating Systems
+     */
+    ifctx = aml_if(aml_equal(func, aml_int(7)));
+    {
+       Aml *pkg = aml_package(2);
+
+       aml_append(ifctx, aml_store(aml_call2("AIDX", bnum, sunum), acpi_index));
+       aml_append(ifctx, aml_store(pkg, ret));
+       /*
+        * Windows calls func=7 without checking if it's available,
+        * as workaround Microsoft has suggested to return invalid for func7
+        * Package, so return 2 elements package but only initialize elements
+        * when acpi_index is supported and leave them uninitialized, which
+        * leads elements to being Uninitialized ObjectType and should trip
+        * Windows into discarding result as an unexpected and prevent setting
+        * bogus 'PCI Label' on the device.
+        */
+       ifctx1 = aml_if(aml_lnot(aml_lor(
+                    aml_equal(acpi_index, zero), aml_equal(acpi_index, not_supp)
+                )));
+       {
+           aml_append(ifctx1, aml_store(acpi_index, aml_index(ret, zero)));
+           /*
+            * optional, if not impl. should return null string
+            */
+           aml_append(ifctx1, aml_store(aml_string("%s", ""),
+                                        aml_index(ret, one)));
+       }
+       aml_append(ifctx, ifctx1);
+
+       aml_append(ifctx, aml_return(ret));
+    }
+
+    aml_append(method, ifctx);
+    return method;
+}
+
+void build_acpi_pci_hotplug(Aml *table, uint64_t pcihp_addr)
+{
+    Aml *scope;
+    Aml *field;
+    Aml *method;
+
+    scope =  aml_scope("_SB.PCI0");
+
+    aml_append(scope,
+        aml_operation_region("PCST", AML_SYSTEM_IO, aml_int(pcihp_addr), 0x08));
+    field = aml_field("PCST", AML_DWORD_ACC, AML_NOLOCK, AML_WRITE_AS_ZEROS);
+    aml_append(field, aml_named_field("PCIU", 32));
+    aml_append(field, aml_named_field("PCID", 32));
+    aml_append(scope, field);
+
+    aml_append(scope,
+        aml_operation_region("SEJ", AML_SYSTEM_IO,
+                             aml_int(pcihp_addr + ACPI_PCIHP_SEJ_BASE), 0x04));
+    field = aml_field("SEJ", AML_DWORD_ACC, AML_NOLOCK, AML_WRITE_AS_ZEROS);
+    aml_append(field, aml_named_field("B0EJ", 32));
+    aml_append(scope, field);
+
+    aml_append(scope,
+        aml_operation_region("BNMR", AML_SYSTEM_IO,
+                             aml_int(pcihp_addr + ACPI_PCIHP_BNMR_BASE), 0x08));
+    field = aml_field("BNMR", AML_DWORD_ACC, AML_NOLOCK, AML_WRITE_AS_ZEROS);
+    aml_append(field, aml_named_field("BNUM", 32));
+    aml_append(field, aml_named_field("PIDX", 32));
+    aml_append(scope, field);
+
+    aml_append(scope, aml_mutex("BLCK", 0));
+
+        method = aml_method("PCEJ", 2, AML_NOTSERIALIZED);
+    aml_append(method, aml_acquire(aml_name("BLCK"), 0xFFFF));
+    aml_append(method, aml_store(aml_arg(0), aml_name("BNUM")));
+    aml_append(method,
+        aml_store(aml_shiftleft(aml_int(1), aml_arg(1)), aml_name("B0EJ")));
+    aml_append(method, aml_release(aml_name("BLCK")));
+    aml_append(method, aml_return(aml_int(0)));
+    aml_append(scope, method);
+
+    method = aml_method("AIDX", 2, AML_NOTSERIALIZED);
+    aml_append(method, aml_acquire(aml_name("BLCK"), 0xFFFF));
+    aml_append(method, aml_store(aml_arg(0), aml_name("BNUM")));
+    aml_append(method,
+        aml_store(aml_shiftleft(aml_int(1), aml_arg(1)), aml_name("PIDX")));
+    aml_append(method, aml_store(aml_name("PIDX"), aml_local(0)));
+    aml_append(method, aml_release(aml_name("BLCK")));
+    aml_append(method, aml_return(aml_local(0)));
+    aml_append(scope, method);
+
+    aml_append(scope, aml_pci_pdsm());
+
+    aml_append(table, scope);
+}
+
 const VMStateDescription vmstate_acpi_pcihp_pci_status = {
     .name = "acpi_pcihp_pci_status",
     .version_id = 1,