Re: [PATCH 25/47] target-info: add target_config_nitro

["Philippe Mathieu-Daudé" <philmd@oss.qualcomm.com>]

On 2026-08-31 9:15, Philippe Mathieu-Daudé wrote:
> On 29/8/26 00:58, Pierrick Bouvier wrote:
> 
> Also wondering why we need a special config for a target device.
> 
> So why are we listing we can not plug? Maybe the bus Kconfig is
> missing the accelerator dependency?
> 
> -- >8 --
> diff --git a/hw/nitro/Kconfig b/hw/nitro/Kconfig
> index cfae85920a0..2e4125f8710 100644
> --- a/hw/nitro/Kconfig
> +++ b/hw/nitro/Kconfig
> @@ -1,4 +1,5 @@
>   config NITRO_VSOCK_BUS
> +    depends on NITRO
>       bool
> 
>   config NITRO_SERIAL_VSOCK
> ---
> 
>> Signed-off-by: Pierrick Bouvier <pierrick.bouvier@oss.qualcomm.com>
>> ---
>>   include/qemu/target-info-impl.h | 2 ++
>>   include/qemu/target-info.h      | 7 +++++++
>>   target-info-def.c               | 3 +++
>>   target-info.c                   | 5 +++++
>>   4 files changed, 17 insertions(+)
>>
>> diff --git a/include/qemu/target-info-impl.h b/include/qemu/target- 
>> info-impl.h
>> index dbd7a5a2071..4f6c898c707 100644
>> --- a/include/qemu/target-info-impl.h
>> +++ b/include/qemu/target-info-impl.h
>> @@ -33,6 +33,8 @@ typedef struct TargetInfo {
>>       /* CONFIG_MULTIPROCESS */
>>       bool config_multiprocess;
>> +    /* CONFIG_NITRO */
>> +    bool config_nitro;
>>   } TargetInfo;
>>   /**
>> diff --git a/include/qemu/target-info.h b/include/qemu/target-info.h
>> index 579c43332fb..d775c94d1e3 100644
>> --- a/include/qemu/target-info.h
>> +++ b/include/qemu/target-info.h
>> @@ -49,6 +49,13 @@ bool target_big_endian(void);
>>    */
>>   bool target_config_multiprocess(void);
>> +/**
>> + * target_config_nitro:
>> + *
>> + * Returns true if target defines CONFIG_NITRO.
>> + */
>> +bool target_config_nitro(void);
>> +
>>   /**
>>    * target_base_arm:
>>    *
>> diff --git a/target-info-def.c b/target-info-def.c
>> index 9d51371f766..96fd1f8c73d 100644
>> --- a/target-info-def.c
>> +++ b/target-info-def.c
>> @@ -46,6 +46,9 @@ static const TargetInfo target_info_stub = {
>>   #ifdef CONFIG_MULTIPROCESS
>>       .config_multiprocess = true,
>>   #endif
>> +#ifdef CONFIG_NITRO
>> +    .config_nitro = true,
>> +#endif
>>   };
>>   target_info_init(target_info_stub)
>> diff --git a/target-info.c b/target-info.c
>> index 5db2a6049ac..67127da16fe 100644
>> --- a/target-info.c
>> +++ b/target-info.c
>> @@ -47,6 +47,11 @@ bool target_config_multiprocess(void)
>>       return target_info()->config_multiprocess;
>>   }
>> +bool target_config_nitro(void)
>> +{
>> +    return target_info()->config_nitro;
>> +}
>> +
>>   bool target_base_arm(void)
>>   {
>>       switch (target_arch()) {
> 

Since the goal of this effort is solely to keep the CLI
output unchanged, we can do simpler without having to add
TargetInfo::config_nitro:

-- >8 --
diff --git a/hw/nitro/Kconfig b/hw/nitro/Kconfig
index cfae85920a..2e4125f871 100644
--- a/hw/nitro/Kconfig
+++ b/hw/nitro/Kconfig
@@ -1,2 +1,3 @@
  config NITRO_VSOCK_BUS
+    depends on NITRO
      bool
diff --git a/hw/nitro/meson.build b/hw/nitro/meson.build
index b9bd0d4300..39a087f8d7 100644
--- a/hw/nitro/meson.build
+++ b/hw/nitro/meson.build
@@ -1 +1,2 @@
+system_ss.add(when: 'CONFIG_NITRO', if_true: files('nitro-common.c'))
  system_ss.add(when: 'CONFIG_NITRO_VSOCK_BUS', if_true: 
files('nitro-vsock-bus.c'))
diff --git a/hw/nitro/nitro-common.c b/hw/nitro/nitro-common.c
new file mode 100644
index 0000000000..cfb47a9a49
--- /dev/null
+++ b/hw/nitro/nitro-common.c
@@ -0,0 +1,15 @@
+/*
+ * Nitro common helpers
+ *
+ * Copyright (c) Qualcomm Technologies, Inc. and/or its subsidiaries.
+ *
+ * SPDX-License-Identifier: GPL-2.0-or-later
+ */
+#include "qemu/osdep.h"
+#include "qemu/target-info.h"
+#include "system/nitro-accel.h"
+
+bool target_config_nitro(void)
+{
+    return (target_aarch64() || target_x86_64()) && nitro_enabled();
+}
diff --git a/include/system/nitro-accel.h b/include/system/nitro-accel.h
index a93aa6fb00..a5126bcf02 100644
--- a/include/system/nitro-accel.h
+++ b/include/system/nitro-accel.h
@@ -18,2 +18,4 @@ static inline bool nitro_enabled(void)

+bool target_config_nitro(void);
+
  #define TYPE_NITRO_ACCEL ACCEL_CLASS_NAME("nitro")
---

Amending in patches #30 "hw/nitro: filter from CONFIG_NITRO":

-- >8 --
diff --git a/hw/nitro/heartbeat.c b/hw/nitro/heartbeat.c
index dc41323266..c4d2a4637e 100644
--- a/hw/nitro/heartbeat.c
+++ b/hw/nitro/heartbeat.c
@@ -21,2 +21,3 @@
  #include "hw/nitro/heartbeat.h"
+#include "system/nitro-accel.h"
  #include "trace.h"
diff --git a/hw/nitro/serial-vsock.c b/hw/nitro/serial-vsock.c
index 1d56c33804..ec5aea4617 100644
--- a/hw/nitro/serial-vsock.c
+++ b/hw/nitro/serial-vsock.c
@@ -25,2 +25,3 @@
  #include "hw/nitro/serial-vsock.h"
+#include "system/nitro-accel.h"
  #include "trace.h"
---

And with another preliminary patch introducing target_x86_64():

-- >8 --
diff --git a/include/qemu/target-info.h b/include/qemu/target-info.h
index 5cce27d4f6..f71a1b8bb6 100644
--- a/include/qemu/target-info.h
+++ b/include/qemu/target-info.h
@@ -128,2 +128,9 @@ bool target_riscv64(void);

+/**
+ * target_x86_64:
+ *
+ * Returns whether the target architecture is 64-bit x86.
+ */
+bool target_x86_64(void);
+
  #endif
diff --git a/target-info.c b/target-info.c
index c9e0be3279..6f03f412b7 100644
--- a/target-info.c
+++ b/target-info.c
@@ -116 +116,6 @@ bool target_riscv64(void)
  }
+
+bool target_x86_64(void)
+{
+    return target_arch() == SYS_EMU_TARGET_X86_64;
+}
---

Only tested on Linux/Aarch64, not Linux/x86_64.