subject:"\[PATCH 3\/4\] arm\: Add the cpufreq device model"

[PATCH 3/4] arm: Add the cpufreq device model

2020-02-12 Thread Ying Fang

On ARM64 platform, CPU frequency is retrieved by ACPI CPPC,
so here we create the virtual cpufreq device to present
the CPPC registers and ACPI _CPC objects.

The default frequency is set host CPU nominal frequency, which
is obtained from the host CPPC sysfs. Other performance data
are set to the same value, since we don't support guest performance scaling.

Performance counters are also not emulated and they simply return 1
if readed, and guest should fallback to use the desired performance
value as the current performance.

Signed-off-by: Heyi Guo 
Signed-off-by: Ying Fang 
---
 hw/acpi/Makefile.objs |   1 +
 hw/acpi/cpufreq.c | 247 ++
 2 files changed, 248 insertions(+)
 create mode 100644 hw/acpi/cpufreq.c

diff --git a/hw/acpi/Makefile.objs b/hw/acpi/Makefile.objs
index 777da07f4d..61530675d4 100644
--- a/hw/acpi/Makefile.objs
+++ b/hw/acpi/Makefile.objs
@@ -16,6 +16,7 @@ common-obj-y += bios-linker-loader.o
 common-obj-y += aml-build.o utils.o
 common-obj-$(CONFIG_ACPI_PCI) += pci.o
 common-obj-$(CONFIG_TPM) += tpm.o
+common-obj-$(CONFIG_CPUFREQ) += cpufreq.o
 
 common-obj-$(CONFIG_IPMI) += ipmi.o
 common-obj-$(call lnot,$(CONFIG_IPMI)) += ipmi-stub.o
diff --git a/hw/acpi/cpufreq.c b/hw/acpi/cpufreq.c
new file mode 100644
index 00..f38087884a
--- /dev/null
+++ b/hw/acpi/cpufreq.c
@@ -0,0 +1,247 @@
+/*
+ * ACPI CPPC register device
+ *
+ * Support for showing CPU frequency in guest OS.
+ *
+ * Copyright (c) 2019 HUAWEI TECHNOLOGIES CO.,LTD.
+ *
+ * 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 .
+ */
+
+#include "qemu/osdep.h"
+#include "hw/sysbus.h"
+#include "chardev/char.h"
+#include "qemu/log.h"
+#include "trace.h"
+#include "qemu/option.h"
+#include "sysemu/sysemu.h"
+#include "hw/acpi/acpi-defs.h"
+#include "qemu/cutils.h"
+#include "qemu/error-report.h"
+#include "hw/boards.h"
+
+#define TYPE_CPUFREQ "cpufreq"
+#define CPUFREQ(obj) OBJECT_CHECK(CpufreqState, (obj), TYPE_CPUFREQ)
+#define NOMINAL_FREQ_FILE "/sys/devices/system/cpu/cpu0/acpi_cppc/nominal_freq"
+#define CPU_MAX_FREQ_FILE 
"/sys/devices/system/cpu/cpu0/cpufreq/cpuinfo_max_freq"
+#define HZ_MAX_LENGTH 1024
+#define MAX_SUPPORT_SPACE 0x1
+
+typedef struct CpufreqState {
+SysBusDevice parent_obj;
+
+MemoryRegion iomem;
+uint32_t HighestPerformance;
+uint32_t NominalPerformance;
+uint32_t LowestNonlinearPerformance;
+uint32_t LowestPerformance;
+uint32_t GuaranteedPerformance;
+uint32_t DesiredPerformance;
+uint64_t ReferencePerformanceCounter;
+uint64_t DeliveredPerformanceCounter;
+uint32_t PerformanceLimited;
+uint32_t LowestFreq;
+uint32_t NominalFreq;
+uint32_t reg_size;
+} CpufreqState;
+
+
+static uint64_t cpufreq_read(void *opaque, hwaddr offset,
+   unsigned size)
+{
+CpufreqState *s = (CpufreqState *)opaque;
+uint64_t r;
+uint64_t n;
+
+MachineState *ms = MACHINE(qdev_get_machine());
+unsigned int smp_cpus = ms->smp.cpus;
+
+if (offset >= smp_cpus * CPPC_REG_PER_CPU_STRIDE) {
+warn_report("cpufreq_read: offset 0x%lx out of range", offset);
+return 0;
+}
+
+n = offset % CPPC_REG_PER_CPU_STRIDE;
+switch (n) {
+case 0:
+r = s->HighestPerformance;
+break;
+case 4:
+r = s->NominalPerformance;
+break;
+case 8:
+r = s->LowestNonlinearPerformance;
+break;
+case 12:
+r = s->LowestPerformance;
+break;
+case 16:
+r = s->GuaranteedPerformance;
+break;
+case 20:
+r = s->DesiredPerformance;
+break;
+/*
+ * We don't have real counters and it is hard to emulate, so always set the
+ * counter value to 1 to rely on Linux to use the DesiredPerformance value
+ * directly.
+ */
+case 24:
+r = s->ReferencePerformanceCounter;
+break;
+/*
+ * Guest may still access the register by 32bit; add the process to
+ * eliminate unnecessary warnings
+ */
+case 28:
+r = s->ReferencePerformanceCounter >> 32;
+break;
+case 32:
+r = s->DeliveredPerformanceCounter;
+break;
+case 36:
+r = s->DeliveredPerformanceCounter >> 32;
+break;
+
+case 40:
+r = s->PerformanceLimited;
+break;
+case 44:
+r = s->LowestFreq;
+break;

[PATCH 3/4] arm: Add the cpufreq device model

2020-02-12 Thread fangying1

From: Ying Fang 

On ARM64 platform, CPU frequency is retrieved by ACPI CPPC,
so here we create the virtual cpufreq device to present
the CPPC registers and ACPI _CPC objects.

The default frequency is set host CPU nominal frequency, which
is obtained from the host CPPC sysfs. Other performance data
are set to the same value, since we don't support guest performance scaling.

Performance counters are also not emulated and they simply return 1
if readed, and guest should fallback to use the desired performance
value as the current performance.

Signed-off-by: Heyi Guo 
Signed-off-by: Ying Fang 
---
 hw/acpi/Makefile.objs |   1 +
 hw/acpi/cpufreq.c | 247 ++
 2 files changed, 248 insertions(+)
 create mode 100644 hw/acpi/cpufreq.c

diff --git a/hw/acpi/Makefile.objs b/hw/acpi/Makefile.objs
index 777da07f4d..61530675d4 100644
--- a/hw/acpi/Makefile.objs
+++ b/hw/acpi/Makefile.objs
@@ -16,6 +16,7 @@ common-obj-y += bios-linker-loader.o
 common-obj-y += aml-build.o utils.o
 common-obj-$(CONFIG_ACPI_PCI) += pci.o
 common-obj-$(CONFIG_TPM) += tpm.o
+common-obj-$(CONFIG_CPUFREQ) += cpufreq.o
 
 common-obj-$(CONFIG_IPMI) += ipmi.o
 common-obj-$(call lnot,$(CONFIG_IPMI)) += ipmi-stub.o
diff --git a/hw/acpi/cpufreq.c b/hw/acpi/cpufreq.c
new file mode 100644
index 00..f38087884a
--- /dev/null
+++ b/hw/acpi/cpufreq.c
@@ -0,0 +1,247 @@
+/*
+ * ACPI CPPC register device
+ *
+ * Support for showing CPU frequency in guest OS.
+ *
+ * Copyright (c) 2019 HUAWEI TECHNOLOGIES CO.,LTD.
+ *
+ * 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 .
+ */
+
+#include "qemu/osdep.h"
+#include "hw/sysbus.h"
+#include "chardev/char.h"
+#include "qemu/log.h"
+#include "trace.h"
+#include "qemu/option.h"
+#include "sysemu/sysemu.h"
+#include "hw/acpi/acpi-defs.h"
+#include "qemu/cutils.h"
+#include "qemu/error-report.h"
+#include "hw/boards.h"
+
+#define TYPE_CPUFREQ "cpufreq"
+#define CPUFREQ(obj) OBJECT_CHECK(CpufreqState, (obj), TYPE_CPUFREQ)
+#define NOMINAL_FREQ_FILE "/sys/devices/system/cpu/cpu0/acpi_cppc/nominal_freq"
+#define CPU_MAX_FREQ_FILE 
"/sys/devices/system/cpu/cpu0/cpufreq/cpuinfo_max_freq"
+#define HZ_MAX_LENGTH 1024
+#define MAX_SUPPORT_SPACE 0x1
+
+typedef struct CpufreqState {
+SysBusDevice parent_obj;
+
+MemoryRegion iomem;
+uint32_t HighestPerformance;
+uint32_t NominalPerformance;
+uint32_t LowestNonlinearPerformance;
+uint32_t LowestPerformance;
+uint32_t GuaranteedPerformance;
+uint32_t DesiredPerformance;
+uint64_t ReferencePerformanceCounter;
+uint64_t DeliveredPerformanceCounter;
+uint32_t PerformanceLimited;
+uint32_t LowestFreq;
+uint32_t NominalFreq;
+uint32_t reg_size;
+} CpufreqState;
+
+
+static uint64_t cpufreq_read(void *opaque, hwaddr offset,
+   unsigned size)
+{
+CpufreqState *s = (CpufreqState *)opaque;
+uint64_t r;
+uint64_t n;
+
+MachineState *ms = MACHINE(qdev_get_machine());
+unsigned int smp_cpus = ms->smp.cpus;
+
+if (offset >= smp_cpus * CPPC_REG_PER_CPU_STRIDE) {
+warn_report("cpufreq_read: offset 0x%lx out of range", offset);
+return 0;
+}
+
+n = offset % CPPC_REG_PER_CPU_STRIDE;
+switch (n) {
+case 0:
+r = s->HighestPerformance;
+break;
+case 4:
+r = s->NominalPerformance;
+break;
+case 8:
+r = s->LowestNonlinearPerformance;
+break;
+case 12:
+r = s->LowestPerformance;
+break;
+case 16:
+r = s->GuaranteedPerformance;
+break;
+case 20:
+r = s->DesiredPerformance;
+break;
+/*
+ * We don't have real counters and it is hard to emulate, so always set the
+ * counter value to 1 to rely on Linux to use the DesiredPerformance value
+ * directly.
+ */
+case 24:
+r = s->ReferencePerformanceCounter;
+break;
+/*
+ * Guest may still access the register by 32bit; add the process to
+ * eliminate unnecessary warnings
+ */
+case 28:
+r = s->ReferencePerformanceCounter >> 32;
+break;
+case 32:
+r = s->DeliveredPerformanceCounter;
+break;
+case 36:
+r = s->DeliveredPerformanceCounter >> 32;
+break;
+
+case 40:
+r = s->PerformanceLimited;
+break;
+case 44:
+r =

[PATCH 3/4] arm: Add the cpufreq device model

[PATCH 3/4] arm: Add the cpufreq device model

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