Add support for "-cpu max" for ARM guests. This CPU type behaves
like "-cpu host" when KVM is enabled, and like a system CPU with
the maximum possible feature set otherwise. (Note that this means
it won't be migratable across versions, as we will likely add
features to it in future.)
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
---
target/arm/cpu-qom.h | 2 ++
target/arm/cpu.c | 24 ++++++++++++++++++++++++
target/arm/cpu64.c | 21 +++++++++++++++++++++
3 files changed, 47 insertions(+)
diff --git a/target/arm/cpu-qom.h b/target/arm/cpu-qom.h
index a42495b..d135ff8 100644
--- a/target/arm/cpu-qom.h
+++ b/target/arm/cpu-qom.h
@@ -33,6 +33,8 @@ struct arm_boot_info;
#define ARM_CPU_GET_CLASS(obj) \
OBJECT_GET_CLASS(ARMCPUClass, (obj), TYPE_ARM_CPU)
+#define TYPE_ARM_MAX_CPU "max-" TYPE_ARM_CPU
+
/**
* ARMCPUClass:
* @parent_realize: The parent class' realize handler.
diff --git a/target/arm/cpu.c b/target/arm/cpu.c
index 9304277..190da97 100644
--- a/target/arm/cpu.c
+++ b/target/arm/cpu.c
@@ -1628,6 +1628,27 @@ static void pxa270c5_initfn(Object *obj)
cpu->reset_sctlr = 0x00000078;
}
+#ifndef TARGET_AARCH64
+/* -cpu max: if KVM is enabled, like -cpu host (best possible with this host);
+ * otherwise, a CPU with as many features enabled as our emulation supports.
+ * The version of '-cpu max' for qemu-system-aarch64 is defined in cpu64.c;
+ * this only needs to handle 32 bits.
+ */
+static void arm_max_initfn(Object *obj)
+{
+ ARMCPU *cpu = ARM_CPU(obj);
+
+ if (kvm_enabled()) {
+ kvm_arm_set_cpu_features_from_host(cpu);
+ } else {
+ cortex_a15_initfn(obj);
+ /* In future we might add feature bits here even if the
+ * real-world A15 doesn't implement them.
+ */
+ }
+}
+#endif
+
#ifdef CONFIG_USER_ONLY
static void arm_any_initfn(Object *obj)
{
@@ -1691,6 +1712,9 @@ static const ARMCPUInfo arm_cpus[] = {
{ .name = "pxa270-b1", .initfn = pxa270b1_initfn },
{ .name = "pxa270-c0", .initfn = pxa270c0_initfn },
{ .name = "pxa270-c5", .initfn = pxa270c5_initfn },
+#ifndef TARGET_AARCH64
+ { .name = "max", .initfn = arm_max_initfn },
+#endif
#ifdef CONFIG_USER_ONLY
{ .name = "any", .initfn = arm_any_initfn },
#endif
diff --git a/target/arm/cpu64.c b/target/arm/cpu64.c
index 670c07a..38dcf32 100644
--- a/target/arm/cpu64.c
+++ b/target/arm/cpu64.c
@@ -28,6 +28,7 @@
#include "hw/arm/arm.h"
#include "sysemu/sysemu.h"
#include "sysemu/kvm.h"
+#include "kvm_arm.h"
static inline void set_feature(CPUARMState *env, int feature)
{
@@ -212,6 +213,25 @@ static void aarch64_a53_initfn(Object *obj)
define_arm_cp_regs(cpu, cortex_a57_a53_cp_reginfo);
}
+/* -cpu max: if KVM is enabled, like -cpu host (best possible with this host);
+ * otherwise, a CPU with as many features enabled as our emulation supports.
+ * The version of '-cpu max' for qemu-system-arm is defined in cpu.c;
+ * this only needs to handle 64 bits.
+ */
+static void aarch64_max_initfn(Object *obj)
+{
+ ARMCPU *cpu = ARM_CPU(obj);
+
+ if (kvm_enabled()) {
+ kvm_arm_set_cpu_features_from_host(cpu);
+ } else {
+ aarch64_a57_initfn(obj);
+ /* In future we might add feature bits here even if the
+ * real-world A57 doesn't implement them.
+ */
+ }
+}
+
#ifdef CONFIG_USER_ONLY
static void aarch64_any_initfn(Object *obj)
{
@@ -240,6 +260,7 @@ typedef struct ARMCPUInfo {
static const ARMCPUInfo aarch64_cpus[] = {
{ .name = "cortex-a57", .initfn = aarch64_a57_initfn },
{ .name = "cortex-a53", .initfn = aarch64_a53_initfn },
+ { .name = "max", .initfn = aarch64_max_initfn },
#ifdef CONFIG_USER_ONLY
{ .name = "any", .initfn = aarch64_any_initfn },
#endif
--
2.7.4
Hi Peter,
On 12/07/2017 03:14 PM, Peter Maydell wrote:
> Add support for "-cpu max" for ARM guests. This CPU type behaves
> like "-cpu host" when KVM is enabled, and like a system CPU with
> the maximum possible feature set otherwise. (Note that this means
> it won't be migratable across versions, as we will likely add
> features to it in future.)
>
> Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
> ---
> target/arm/cpu-qom.h | 2 ++
> target/arm/cpu.c | 24 ++++++++++++++++++++++++
> target/arm/cpu64.c | 21 +++++++++++++++++++++
> 3 files changed, 47 insertions(+)
>
> diff --git a/target/arm/cpu-qom.h b/target/arm/cpu-qom.h
> index a42495b..d135ff8 100644
> --- a/target/arm/cpu-qom.h
> +++ b/target/arm/cpu-qom.h
> @@ -33,6 +33,8 @@ struct arm_boot_info;
> #define ARM_CPU_GET_CLASS(obj) \
> OBJECT_GET_CLASS(ARMCPUClass, (obj), TYPE_ARM_CPU)
>
> +#define TYPE_ARM_MAX_CPU "max-" TYPE_ARM_CPU
> +
> /**
> * ARMCPUClass:
> * @parent_realize: The parent class' realize handler.
> diff --git a/target/arm/cpu.c b/target/arm/cpu.c
> index 9304277..190da97 100644
> --- a/target/arm/cpu.c
> +++ b/target/arm/cpu.c
> @@ -1628,6 +1628,27 @@ static void pxa270c5_initfn(Object *obj)
> cpu->reset_sctlr = 0x00000078;
> }
>
> +#ifndef TARGET_AARCH64
> +/* -cpu max: if KVM is enabled, like -cpu host (best possible with this host);
> + * otherwise, a CPU with as many features enabled as our emulation supports.
> + * The version of '-cpu max' for qemu-system-aarch64 is defined in cpu64.c;
> + * this only needs to handle 32 bits.
> + */
> +static void arm_max_initfn(Object *obj)
> +{
> + ARMCPU *cpu = ARM_CPU(obj);
> +
> + if (kvm_enabled()) {
> + kvm_arm_set_cpu_features_from_host(cpu);
> + } else {
> + cortex_a15_initfn(obj);> + /* In future we might add feature bits here even if the
> + * real-world A15 doesn't implement them.
> + */
Why not use arm_any_initfn() here?
Actually what seems cleaner is to move "any" features here, and kill the
"any" cpu, using "max" for this purpose.
> + }
> +}
> +#endif
> +
> #ifdef CONFIG_USER_ONLY
> static void arm_any_initfn(Object *obj)
> {
> @@ -1691,6 +1712,9 @@ static const ARMCPUInfo arm_cpus[] = {
> { .name = "pxa270-b1", .initfn = pxa270b1_initfn },
> { .name = "pxa270-c0", .initfn = pxa270c0_initfn },
> { .name = "pxa270-c5", .initfn = pxa270c5_initfn },
> +#ifndef TARGET_AARCH64
> + { .name = "max", .initfn = arm_max_initfn },
> +#endif
> #ifdef CONFIG_USER_ONLY
> { .name = "any", .initfn = arm_any_initfn },
> #endif
and we can remove the last 3 lines.
> diff --git a/target/arm/cpu64.c b/target/arm/cpu64.c
> index 670c07a..38dcf32 100644
> --- a/target/arm/cpu64.c
> +++ b/target/arm/cpu64.c
> @@ -28,6 +28,7 @@
> #include "hw/arm/arm.h"
> #include "sysemu/sysemu.h"
> #include "sysemu/kvm.h"
> +#include "kvm_arm.h"
>
> static inline void set_feature(CPUARMState *env, int feature)
> {
> @@ -212,6 +213,25 @@ static void aarch64_a53_initfn(Object *obj)
> define_arm_cp_regs(cpu, cortex_a57_a53_cp_reginfo);
> }
>
> +/* -cpu max: if KVM is enabled, like -cpu host (best possible with this host);
> + * otherwise, a CPU with as many features enabled as our emulation supports.
> + * The version of '-cpu max' for qemu-system-arm is defined in cpu.c;
> + * this only needs to handle 64 bits.
> + */
> +static void aarch64_max_initfn(Object *obj)
> +{
> + ARMCPU *cpu = ARM_CPU(obj);
> +
> + if (kvm_enabled()) {
> + kvm_arm_set_cpu_features_from_host(cpu);
> + } else {
> + aarch64_a57_initfn(obj);
> + /* In future we might add feature bits here even if the
> + * real-world A57 doesn't implement them.
> + */
> + }
> +}
> +
> #ifdef CONFIG_USER_ONLY
> static void aarch64_any_initfn(Object *obj)
> {
> @@ -240,6 +260,7 @@ typedef struct ARMCPUInfo {
> static const ARMCPUInfo aarch64_cpus[] = {
> { .name = "cortex-a57", .initfn = aarch64_a57_initfn },
> { .name = "cortex-a53", .initfn = aarch64_a53_initfn },
> + { .name = "max", .initfn = aarch64_max_initfn },
> #ifdef CONFIG_USER_ONLY
> { .name = "any", .initfn = aarch64_any_initfn },
> #endif
>
On 26 January 2018 at 14:29, Philippe Mathieu-Daudé <f4bug@amsat.org> wrote:
> Hi Peter,
>
> On 12/07/2017 03:14 PM, Peter Maydell wrote:
>> Add support for "-cpu max" for ARM guests. This CPU type behaves
>> like "-cpu host" when KVM is enabled, and like a system CPU with
>> the maximum possible feature set otherwise. (Note that this means
>> it won't be migratable across versions, as we will likely add
>> features to it in future.)
>>
>> Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
>> ---
>> +#ifndef TARGET_AARCH64
>> +/* -cpu max: if KVM is enabled, like -cpu host (best possible with this host);
>> + * otherwise, a CPU with as many features enabled as our emulation supports.
>> + * The version of '-cpu max' for qemu-system-aarch64 is defined in cpu64.c;
>> + * this only needs to handle 32 bits.
>> + */
>> +static void arm_max_initfn(Object *obj)
>> +{
>> + ARMCPU *cpu = ARM_CPU(obj);
>> +
>> + if (kvm_enabled()) {
>> + kvm_arm_set_cpu_features_from_host(cpu);
>> + } else {
>> + cortex_a15_initfn(obj);> + /* In future we might add feature bits here even if the
>> + * real-world A15 doesn't implement them.
>> + */
>
> Why not use arm_any_initfn() here?
That function (and the 'any' cpu) are deliberately only
included in the linux-user binaries, not the system-emulation binaries.
(Also arm_any_initfn() only initializes userspace-visible stuff, it
doesn't provide ID register values etc for kernel-visible things.)
> Actually what seems cleaner is to move "any" features here, and kill the
> "any" cpu, using "max" for this purpose.
We can't kill 'any', that would break back-compatibility
of command lines.
thanks
-- PMM
On 01/26/2018 11:33 AM, Peter Maydell wrote:
> On 26 January 2018 at 14:29, Philippe Mathieu-Daudé <f4bug@amsat.org> wrote:
>> Hi Peter,
>>
>> On 12/07/2017 03:14 PM, Peter Maydell wrote:
>>> Add support for "-cpu max" for ARM guests. This CPU type behaves
>>> like "-cpu host" when KVM is enabled, and like a system CPU with
>>> the maximum possible feature set otherwise. (Note that this means
>>> it won't be migratable across versions, as we will likely add
>>> features to it in future.)
>>>
>>> Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
>>> ---
>
>>> +#ifndef TARGET_AARCH64
>>> +/* -cpu max: if KVM is enabled, like -cpu host (best possible with this host);
>>> + * otherwise, a CPU with as many features enabled as our emulation supports.
>>> + * The version of '-cpu max' for qemu-system-aarch64 is defined in cpu64.c;
>>> + * this only needs to handle 32 bits.
>>> + */
>>> +static void arm_max_initfn(Object *obj)
>>> +{
>>> + ARMCPU *cpu = ARM_CPU(obj);
>>> +
>>> + if (kvm_enabled()) {
>>> + kvm_arm_set_cpu_features_from_host(cpu);
>>> + } else {
>>> + cortex_a15_initfn(obj);> + /* In future we might add feature bits here even if the
>>> + * real-world A15 doesn't implement them.
>>> + */
>>
>> Why not use arm_any_initfn() here?
>
> That function (and the 'any' cpu) are deliberately only
> included in the linux-user binaries, not the system-emulation binaries.
why not use the V8 features?
> (Also arm_any_initfn() only initializes userspace-visible stuff, it
> doesn't provide ID register values etc for kernel-visible things.)
I'd still use an unique arm_max_initfn() such
// initializes userspace-visible stuff
#ifndef CONFIG_USER_ONLY
// initializes kernel-visible things
#endif
>
>> Actually what seems cleaner is to move "any" features here, and kill the
>> "any" cpu, using "max" for this purpose.
>
> We can't kill 'any', that would break back-compatibility
> of command lines.
and use an alias for 'any' -> 'max' or just
{ .name = "any", .initfn = arm_max_initfn }, /* backward compat */
Anyway:
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
>
> thanks
> -- PMM
>
On 26 January 2018 at 15:44, Philippe Mathieu-Daudé <f4bug@amsat.org> wrote:
> On 01/26/2018 11:33 AM, Peter Maydell wrote:
>> On 26 January 2018 at 14:29, Philippe Mathieu-Daudé <f4bug@amsat.org> wrote:
>>> Why not use arm_any_initfn() here?
>>
>> That function (and the 'any' cpu) are deliberately only
>> included in the linux-user binaries, not the system-emulation binaries.
>
> why not use the V8 features?
What v8 features?
>> (Also arm_any_initfn() only initializes userspace-visible stuff, it
>> doesn't provide ID register values etc for kernel-visible things.)
>
> I'd still use an unique arm_max_initfn() such
>
> // initializes userspace-visible stuff
> #ifndef CONFIG_USER_ONLY
> // initializes kernel-visible things
> #endif
>>> Actually what seems cleaner is to move "any" features here, and kill the
>>> "any" cpu, using "max" for this purpose.
>>
>> We can't kill 'any', that would break back-compatibility
>> of command lines.
>
> and use an alias for 'any' -> 'max' or just
>
> { .name = "any", .initfn = arm_max_initfn }, /* backward compat */
Yes, we could probably do something similar to this.
thanks
-- PMM
On Fri, 2 Feb 2018 17:54:43 +0000
Peter Maydell <peter.maydell@linaro.org> wrote:
> On 26 January 2018 at 15:44, Philippe Mathieu-Daudé <f4bug@amsat.org> wrote:
> > On 01/26/2018 11:33 AM, Peter Maydell wrote:
> >> On 26 January 2018 at 14:29, Philippe Mathieu-Daudé <f4bug@amsat.org> wrote:
> >>> Why not use arm_any_initfn() here?
> >>
> >> That function (and the 'any' cpu) are deliberately only
> >> included in the linux-user binaries, not the system-emulation binaries.
> >
> > why not use the V8 features?
>
> What v8 features?
>
> >> (Also arm_any_initfn() only initializes userspace-visible stuff, it
> >> doesn't provide ID register values etc for kernel-visible things.)
> >
> > I'd still use an unique arm_max_initfn() such
> >
> > // initializes userspace-visible stuff
> > #ifndef CONFIG_USER_ONLY
> > // initializes kernel-visible things
> > #endif
>
> >>> Actually what seems cleaner is to move "any" features here, and kill the
> >>> "any" cpu, using "max" for this purpose.
> >>
> >> We can't kill 'any', that would break back-compatibility
> >> of command lines.
> >
> > and use an alias for 'any' -> 'max' or just
I'd suggest to place easy any -> max compat hack into
arm_cpu_class_by_name()
> >
> > { .name = "any", .initfn = arm_max_initfn }, /* backward compat */
>
> Yes, we could probably do something similar to this.
>
> thanks
> -- PMM
>
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