[RFC PATCH v3 23/31] acpi/cxl: Add _OSC implementation (9.14.2)

Ben Widawsky
2021-02-02T01:02:13Z

CXL 2.0 specification adds 2 new dwords to the existing _OSC definition
from PCIe. The new dwords are accessed with a new uuid. This
implementation supports what is in the specification.

We are currently in the process of trying to define a new definition for
_OSC. See later work for an explanation.

Signed-off-by: Ben Widawsky <ben.widawsky@intel.com>
---
hw/acpi/Kconfig | 5 ++
hw/acpi/cxl.c | 104 ++++++++++++++++++++++++++++++++++++++++++
hw/acpi/meson.build | 1 +
hw/i386/acpi-build.c | 12 ++++-
include/hw/acpi/cxl.h | 23 ++++++++++
5 files changed, 144 insertions(+), 1 deletion(-)
create mode 100644 hw/acpi/cxl.c
create mode 100644 include/hw/acpi/cxl.h

diff --git a/hw/acpi/Kconfig b/hw/acpi/Kconfig
index 1932f66af8..b27907953e 100644
--- a/hw/acpi/Kconfig
+++ b/hw/acpi/Kconfig
@@ -5,6 +5,7 @@ config ACPI_X86
bool
select ACPI
select ACPI_NVDIMM
+ select ACPI_CXL
select ACPI_CPU_HOTPLUG
select ACPI_MEMORY_HOTPLUG
select ACPI_HMAT
@@ -42,3 +43,7 @@ config ACPI_VMGENID
depends on PC

config ACPI_HW_REDUCED
+
+config ACPI_CXL
+ bool
+ depends on ACPI
diff --git a/hw/acpi/cxl.c b/hw/acpi/cxl.c
new file mode 100644
index 0000000000..7124d5a1a3
--- /dev/null
+++ b/hw/acpi/cxl.c
@@ -0,0 +1,104 @@
+/*
+ * CXL ACPI Implementation
+ *
+ * Copyright(C) 2020 Intel Corporation.
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, see <http://www.gnu.org/licenses/>
+ */
+
+#include "qemu/osdep.h"
+#include "hw/cxl/cxl.h"
+#include "hw/acpi/acpi.h"
+#include "hw/acpi/aml-build.h"
+#include "hw/acpi/bios-linker-loader.h"
+#include "hw/acpi/cxl.h"
+#include "qapi/error.h"
+#include "qemu/uuid.h"
+
+static Aml *__build_cxl_osc_method(void)
+{
+ Aml *method, *if_uuid, *else_uuid, *if_arg1_not_1, *if_cxl, *if_caps_masked;
+ Aml *a_ctrl = aml_local(0);
+ Aml *a_cdw1 = aml_name("CDW1");
+
+ method = aml_method("_OSC", 4, AML_NOTSERIALIZED);
+ aml_append(method, aml_create_dword_field(aml_arg(3), aml_int(0), "CDW1"));
+
+ /* 9.14.2.1.4 */
+ if_uuid = aml_if(
+ aml_lor(aml_equal(aml_arg(0),
+ aml_touuid("33DB4D5B-1FF7-401C-9657-7441C03DD766")),
+ aml_equal(aml_arg(0),
+ aml_touuid("68F2D50B-C469-4D8A-BD3D-941A103FD3FC"))));
+ aml_append(if_uuid, aml_create_dword_field(aml_arg(3), aml_int(4), "CDW2"));
+ aml_append(if_uuid, aml_create_dword_field(aml_arg(3), aml_int(8), "CDW3"));
+
+ aml_append(if_uuid, aml_store(aml_name("CDW3"), a_ctrl));
+
+ /* This is all the same as what's used for PCIe */
+ aml_append(if_uuid,
+ aml_and(aml_name("CTRL"), aml_int(0x1F), aml_name("CTRL")));
+
+ if_arg1_not_1 = aml_if(aml_lnot(aml_equal(aml_arg(1), aml_int(0x1))));
+ /* Unknown revision */
+ aml_append(if_arg1_not_1, aml_or(a_cdw1, aml_int(0x08), a_cdw1));
+ aml_append(if_uuid, if_arg1_not_1);
+
+ if_caps_masked = aml_if(aml_lnot(aml_equal(aml_name("CDW3"), a_ctrl)));
+ /* Capability bits were masked */
+ aml_append(if_caps_masked, aml_or(a_cdw1, aml_int(0x10), a_cdw1));
+ aml_append(if_uuid, if_caps_masked);
+
+ aml_append(if_uuid, aml_store(aml_name("CDW2"), aml_name("SUPP")));
+ aml_append(if_uuid, aml_store(aml_name("CDW3"), aml_name("CTRL")));
+
+ if_cxl = aml_if(aml_equal(
+ aml_arg(0), aml_touuid("68F2D50B-C469-4D8A-BD3D-941A103FD3FC")));
+ /* CXL support field */
+ aml_append(if_cxl, aml_create_dword_field(aml_arg(3), aml_int(12), "CDW4"));
+ /* CXL capabilities */
+ aml_append(if_cxl, aml_create_dword_field(aml_arg(3), aml_int(16), "CDW5"));
+ aml_append(if_cxl, aml_store(aml_name("CDW4"), aml_name("SUPC")));
+ aml_append(if_cxl, aml_store(aml_name("CDW5"), aml_name("CTRC")));
+
+ /* CXL 2.0 Port/Device Register access */
+ aml_append(if_cxl,
+ aml_or(aml_name("CDW5"), aml_int(0x1), aml_name("CDW5")));
+ aml_append(if_uuid, if_cxl);
+
+ /* Update DWORD3 (the return value) */
+ aml_append(if_uuid, aml_store(a_ctrl, aml_name("CDW3")));
+
+ aml_append(if_uuid, aml_return(aml_arg(3)));
+ aml_append(method, if_uuid);
+
+ else_uuid = aml_else();
+
+ /* unrecognized uuid */
+ aml_append(else_uuid,
+ aml_or(aml_name("CDW1"), aml_int(0x4), aml_name("CDW1")));
+ aml_append(else_uuid, aml_return(aml_arg(3)));
+ aml_append(method, else_uuid);
+
+ return method;
+}
+
+void build_cxl_osc_method(Aml *dev)
+{
+ aml_append(dev, aml_name_decl("SUPP", aml_int(0)));
+ aml_append(dev, aml_name_decl("CTRL", aml_int(0)));
+ aml_append(dev, aml_name_decl("SUPC", aml_int(0)));
+ aml_append(dev, aml_name_decl("CTRC", aml_int(0)));
+ aml_append(dev, __build_cxl_osc_method());
+}
diff --git a/hw/acpi/meson.build b/hw/acpi/meson.build
index dd69577212..9f5c5ced28 100644
--- a/hw/acpi/meson.build
+++ b/hw/acpi/meson.build
@@ -10,6 +10,7 @@ acpi_ss.add(when: 'CONFIG_ACPI_CPU_HOTPLUG', if_true: files('cpu_hotplug.c'))
acpi_ss.add(when: 'CONFIG_ACPI_MEMORY_HOTPLUG', if_true: files('memory_hotplug.c'))
acpi_ss.add(when: 'CONFIG_ACPI_NVDIMM', if_true: files('nvdimm.c'))
acpi_ss.add(when: 'CONFIG_ACPI_PCI', if_true: files('pci.c'))
+acpi_ss.add(when: 'CONFIG_ACPI_CXL', if_true: files('cxl.c'))
acpi_ss.add(when: 'CONFIG_ACPI_VMGENID', if_true: files('vmgenid.c'))
acpi_ss.add(when: 'CONFIG_ACPI_HW_REDUCED', if_true: files('generic_event_device.c'))
acpi_ss.add(when: 'CONFIG_ACPI_HMAT', if_true: files('hmat.c'))
diff --git a/hw/i386/acpi-build.c b/hw/i386/acpi-build.c
index ecdc10b148..2c2293b55f 100644
--- a/hw/i386/acpi-build.c
+++ b/hw/i386/acpi-build.c
@@ -66,6 +66,7 @@
#include "hw/acpi/aml-build.h"
#include "hw/acpi/utils.h"
#include "hw/acpi/pci.h"
+#include "hw/acpi/cxl.h"

#include "qom/qom-qobject.h"
#include "hw/i386/amd_iommu.h"
@@ -1201,11 +1202,20 @@ static void init_pci_acpi(Aml *dev, int uid, int type)
if (type == PCI) {
aml_append(dev, aml_name_decl("_HID", aml_eisaid("PNP0A03")));
aml_append(dev, aml_name_decl("_UID", aml_int(uid)));
- } else {
+ } else if (type == PCIE) {
aml_append(dev, aml_name_decl("_HID", aml_eisaid("PNP0A08")));
aml_append(dev, aml_name_decl("_CID", aml_eisaid("PNP0A03")));
aml_append(dev, aml_name_decl("_UID", aml_int(uid)));
aml_append(dev, build_q35_osc_method());
+ } else /* CXL */ {
+ struct Aml *pkg = aml_package(2);
+
+ aml_append(dev, aml_name_decl("_HID", aml_string("ACPI0016")));
+ aml_append(pkg, aml_eisaid("PNP0A08"));
+ aml_append(pkg, aml_eisaid("PNP0A03"));
+ aml_append(dev, aml_name_decl("_CID", pkg));
+ aml_append(dev, aml_name_decl("_UID", aml_int(uid)));
+ build_cxl_osc_method(dev);
}
}

diff --git a/include/hw/acpi/cxl.h b/include/hw/acpi/cxl.h
new file mode 100644
index 0000000000..7b8f3b8a2e
--- /dev/null
+++ b/include/hw/acpi/cxl.h
@@ -0,0 +1,23 @@
+/*
+ * Copyright (C) 2020 Intel Corporation
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, see <http://www.gnu.org/licenses/>.
+ */
+
+#ifndef HW_ACPI_CXL_H
+#define HW_ACPI_CXL_H
+
+void build_cxl_osc_method(Aml *dev);
+
+#endif
--
2.30.0