From 590f5f09b7e11682e2607633bb08fcdac2c2bb4c Mon Sep 17 00:00:00 2001
From: Laszlo Ersek <lersek@redhat.com>
Date: Wed, 26 Feb 2020 23:11:47 +0100
Subject: [PATCH] OvmfPkg/CpuHotplugSmm: add hotplug register block helper
functions
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Add a handful of simple functions for accessing QEMU's hotplug registers
more conveniently. These functions thinly wrap some of the registers
described in "docs/specs/acpi_cpu_hotplug.txt" in the QEMU tree. The
functions hang (by design) if they encounter an internal failure.
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Igor Mammedov <imammedo@redhat.com>
Cc: Jiewen Yao <jiewen.yao@intel.com>
Cc: Jordan Justen <jordan.l.justen@intel.com>
Cc: Michael Kinney <michael.d.kinney@intel.com>
Cc: Philippe Mathieu-Daudé <philmd@redhat.com>
Ref: https://bugzilla.tianocore.org/show_bug.cgi?id=1512
Signed-off-by: Laszlo Ersek <lersek@redhat.com>
Message-Id: <20200226221156.29589-8-lersek@redhat.com>
Reviewed-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Reviewed-by: Philippe Mathieu-Daude <philmd@redhat.com>
Tested-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
---
OvmfPkg/CpuHotplugSmm/CpuHotplugSmm.inf | 2 +
OvmfPkg/CpuHotplugSmm/QemuCpuhp.c | 136 ++++++++++++++++++++++++
OvmfPkg/CpuHotplugSmm/QemuCpuhp.h | 47 ++++++++
3 files changed, 185 insertions(+)
create mode 100644 OvmfPkg/CpuHotplugSmm/QemuCpuhp.c
create mode 100644 OvmfPkg/CpuHotplugSmm/QemuCpuhp.h
diff --git a/OvmfPkg/CpuHotplugSmm/CpuHotplugSmm.inf b/OvmfPkg/CpuHotplugSmm/CpuHotplugSmm.inf
index fa70858a8d..ac4ca4c1f4 100644
--- a/OvmfPkg/CpuHotplugSmm/CpuHotplugSmm.inf
+++ b/OvmfPkg/CpuHotplugSmm/CpuHotplugSmm.inf
@@ -23,6 +23,8 @@
[Sources]
CpuHotplug.c
+ QemuCpuhp.c
+ QemuCpuhp.h
[Packages]
MdePkg/MdePkg.dec
diff --git a/OvmfPkg/CpuHotplugSmm/QemuCpuhp.c b/OvmfPkg/CpuHotplugSmm/QemuCpuhp.c
new file mode 100644
index 0000000000..31e46f5193
--- /dev/null
+++ b/OvmfPkg/CpuHotplugSmm/QemuCpuhp.c
@@ -0,0 +1,136 @@
+/** @file
+ Simple wrapper functions that access QEMU's modern CPU hotplug register
+ block.
+
+ These functions thinly wrap some of the registers described in
+ "docs/specs/acpi_cpu_hotplug.txt" in the QEMU source. IO Ports are accessed
+ via EFI_MM_CPU_IO_PROTOCOL. If a protocol call fails, these functions don't
+ return.
+
+ Copyright (c) 2020, Red Hat, Inc.
+
+ SPDX-License-Identifier: BSD-2-Clause-Patent
+**/
+
+#include <IndustryStandard/Q35MchIch9.h> // ICH9_CPU_HOTPLUG_BASE
+#include <IndustryStandard/QemuCpuHotplug.h> // QEMU_CPUHP_R_CMD_DATA2
+#include <Library/BaseLib.h> // CpuDeadLoop()
+#include <Library/DebugLib.h> // DEBUG()
+
+#include "QemuCpuhp.h"
+
+UINT32
+QemuCpuhpReadCommandData2 (
+ IN CONST EFI_MM_CPU_IO_PROTOCOL *MmCpuIo
+ )
+{
+ UINT32 CommandData2;
+ EFI_STATUS Status;
+
+ CommandData2 = 0;
+ Status = MmCpuIo->Io.Read (
+ MmCpuIo,
+ MM_IO_UINT32,
+ ICH9_CPU_HOTPLUG_BASE + QEMU_CPUHP_R_CMD_DATA2,
+ 1,
+ &CommandData2
+ );
+ if (EFI_ERROR (Status)) {
+ DEBUG ((DEBUG_ERROR, "%a: %r\n", __FUNCTION__, Status));
+ ASSERT (FALSE);
+ CpuDeadLoop ();
+ }
+ return CommandData2;
+}
+
+UINT8
+QemuCpuhpReadCpuStatus (
+ IN CONST EFI_MM_CPU_IO_PROTOCOL *MmCpuIo
+ )
+{
+ UINT8 CpuStatus;
+ EFI_STATUS Status;
+
+ CpuStatus = 0;
+ Status = MmCpuIo->Io.Read (
+ MmCpuIo,
+ MM_IO_UINT8,
+ ICH9_CPU_HOTPLUG_BASE + QEMU_CPUHP_R_CPU_STAT,
+ 1,
+ &CpuStatus
+ );
+ if (EFI_ERROR (Status)) {
+ DEBUG ((DEBUG_ERROR, "%a: %r\n", __FUNCTION__, Status));
+ ASSERT (FALSE);
+ CpuDeadLoop ();
+ }
+ return CpuStatus;
+}
+
+UINT32
+QemuCpuhpReadCommandData (
+ IN CONST EFI_MM_CPU_IO_PROTOCOL *MmCpuIo
+ )
+{
+ UINT32 CommandData;
+ EFI_STATUS Status;
+
+ CommandData = 0;
+ Status = MmCpuIo->Io.Read (
+ MmCpuIo,
+ MM_IO_UINT32,
+ ICH9_CPU_HOTPLUG_BASE + QEMU_CPUHP_RW_CMD_DATA,
+ 1,
+ &CommandData
+ );
+ if (EFI_ERROR (Status)) {
+ DEBUG ((DEBUG_ERROR, "%a: %r\n", __FUNCTION__, Status));
+ ASSERT (FALSE);
+ CpuDeadLoop ();
+ }
+ return CommandData;
+}
+
+VOID
+QemuCpuhpWriteCpuSelector (
+ IN CONST EFI_MM_CPU_IO_PROTOCOL *MmCpuIo,
+ IN UINT32 Selector
+ )
+{
+ EFI_STATUS Status;
+
+ Status = MmCpuIo->Io.Write (
+ MmCpuIo,
+ MM_IO_UINT32,
+ ICH9_CPU_HOTPLUG_BASE + QEMU_CPUHP_W_CPU_SEL,
+ 1,
+ &Selector
+ );
+ if (EFI_ERROR (Status)) {
+ DEBUG ((DEBUG_ERROR, "%a: %r\n", __FUNCTION__, Status));
+ ASSERT (FALSE);
+ CpuDeadLoop ();
+ }
+}
+
+VOID
+QemuCpuhpWriteCommand (
+ IN CONST EFI_MM_CPU_IO_PROTOCOL *MmCpuIo,
+ IN UINT8 Command
+ )
+{
+ EFI_STATUS Status;
+
+ Status = MmCpuIo->Io.Write (
+ MmCpuIo,
+ MM_IO_UINT8,
+ ICH9_CPU_HOTPLUG_BASE + QEMU_CPUHP_W_CMD,
+ 1,
+ &Command
+ );
+ if (EFI_ERROR (Status)) {
+ DEBUG ((DEBUG_ERROR, "%a: %r\n", __FUNCTION__, Status));
+ ASSERT (FALSE);
+ CpuDeadLoop ();
+ }
+}
diff --git a/OvmfPkg/CpuHotplugSmm/QemuCpuhp.h b/OvmfPkg/CpuHotplugSmm/QemuCpuhp.h
new file mode 100644
index 0000000000..82f88f0b73
--- /dev/null
+++ b/OvmfPkg/CpuHotplugSmm/QemuCpuhp.h
@@ -0,0 +1,47 @@
+/** @file
+ Simple wrapper functions that access QEMU's modern CPU hotplug register
+ block.
+
+ These functions thinly wrap some of the registers described in
+ "docs/specs/acpi_cpu_hotplug.txt" in the QEMU source. IO Ports are accessed
+ via EFI_MM_CPU_IO_PROTOCOL. If a protocol call fails, these functions don't
+ return.
+
+ Copyright (c) 2020, Red Hat, Inc.
+
+ SPDX-License-Identifier: BSD-2-Clause-Patent
+**/
+
+#ifndef QEMU_CPUHP_H_
+#define QEMU_CPUHP_H_
+
+#include <Protocol/MmCpuIo.h> // EFI_MM_CPU_IO_PROTOCOL
+
+UINT32
+QemuCpuhpReadCommandData2 (
+ IN CONST EFI_MM_CPU_IO_PROTOCOL *MmCpuIo
+ );
+
+UINT8
+QemuCpuhpReadCpuStatus (
+ IN CONST EFI_MM_CPU_IO_PROTOCOL *MmCpuIo
+ );
+
+UINT32
+QemuCpuhpReadCommandData (
+ IN CONST EFI_MM_CPU_IO_PROTOCOL *MmCpuIo
+ );
+
+VOID
+QemuCpuhpWriteCpuSelector (
+ IN CONST EFI_MM_CPU_IO_PROTOCOL *MmCpuIo,
+ IN UINT32 Selector
+ );
+
+VOID
+QemuCpuhpWriteCommand (
+ IN CONST EFI_MM_CPU_IO_PROTOCOL *MmCpuIo,
+ IN UINT8 Command
+ );
+
+#endif // QEMU_CPUHP_H_