2024-01-27 16:27:47

by Masahiro Yamada

[permalink] [raw]
Subject: [PATCH 1/1] MIPS: move unselectable entries out of the "CPU type" choice

Move the following entries out of the "CPU type" choice:

- LOONGSON3_ENHANCEMENT
- CPU_LOONGSON3_WORKAROUNDS
- CPU_LOONGSON3_CPUCFG_EMULATION

These entries cannot be selected from the choice because they depend on
CPU_LOONGSON64, which is also located in the same choice.

In fact, Kconfig does not consider them as choice values because they
become children of CPU_LOOONGSON64 due to the automatic submenu creation
in menu_finalize().

However, it is hard to understand this behavior unless you are familiar
with the Kconfig internals.

"choice" should contain only selectable entries.

Signed-off-by: Masahiro Yamada <[email protected]>
---

arch/mips/Kconfig | 76 +++++++++++++++++++++++------------------------
1 file changed, 38 insertions(+), 38 deletions(-)

diff --git a/arch/mips/Kconfig b/arch/mips/Kconfig
index 797ae590ebdb..a70b4f959fb1 100644
--- a/arch/mips/Kconfig
+++ b/arch/mips/Kconfig
@@ -1269,44 +1269,6 @@ config CPU_LOONGSON64
3B1000, 3B1500, 3A2000, 3A3000 and 3A4000) processors. However, old
Loongson-2E/2F is not covered here and will be removed in future.

-config LOONGSON3_ENHANCEMENT
- bool "New Loongson-3 CPU Enhancements"
- default n
- depends on CPU_LOONGSON64
- help
- New Loongson-3 cores (since Loongson-3A R2, as opposed to Loongson-3A
- R1, Loongson-3B R1 and Loongson-3B R2) has many enhancements, such as
- FTLB, L1-VCache, EI/DI/Wait/Prefetch instruction, DSP/DSPr2 ASE, User
- Local register, Read-Inhibit/Execute-Inhibit, SFB (Store Fill Buffer),
- Fast TLB refill support, etc.
-
- This option enable those enhancements which are not probed at run
- time. If you want a generic kernel to run on all Loongson 3 machines,
- please say 'N' here. If you want a high-performance kernel to run on
- new Loongson-3 machines only, please say 'Y' here.
-
-config CPU_LOONGSON3_WORKAROUNDS
- bool "Loongson-3 LLSC Workarounds"
- default y if SMP
- depends on CPU_LOONGSON64
- help
- Loongson-3 processors have the llsc issues which require workarounds.
- Without workarounds the system may hang unexpectedly.
-
- Say Y, unless you know what you are doing.
-
-config CPU_LOONGSON3_CPUCFG_EMULATION
- bool "Emulate the CPUCFG instruction on older Loongson cores"
- default y
- depends on CPU_LOONGSON64
- help
- Loongson-3A R4 and newer have the CPUCFG instruction available for
- userland to query CPU capabilities, much like CPUID on x86. This
- option provides emulation of the instruction on older Loongson
- cores, back to Loongson-3A1000.
-
- If unsure, please say Y.
-
config CPU_LOONGSON2E
bool "Loongson 2E"
depends on SYS_HAS_CPU_LOONGSON2E
@@ -1644,6 +1606,44 @@ config CPU_BMIPS

endchoice

+config LOONGSON3_ENHANCEMENT
+ bool "New Loongson-3 CPU Enhancements"
+ default n
+ depends on CPU_LOONGSON64
+ help
+ New Loongson-3 cores (since Loongson-3A R2, as opposed to Loongson-3A
+ R1, Loongson-3B R1 and Loongson-3B R2) has many enhancements, such as
+ FTLB, L1-VCache, EI/DI/Wait/Prefetch instruction, DSP/DSPr2 ASE, User
+ Local register, Read-Inhibit/Execute-Inhibit, SFB (Store Fill Buffer),
+ Fast TLB refill support, etc.
+
+ This option enable those enhancements which are not probed at run
+ time. If you want a generic kernel to run on all Loongson 3 machines,
+ please say 'N' here. If you want a high-performance kernel to run on
+ new Loongson-3 machines only, please say 'Y' here.
+
+config CPU_LOONGSON3_WORKAROUNDS
+ bool "Loongson-3 LLSC Workarounds"
+ default y if SMP
+ depends on CPU_LOONGSON64
+ help
+ Loongson-3 processors have the llsc issues which require workarounds.
+ Without workarounds the system may hang unexpectedly.
+
+ Say Y, unless you know what you are doing.
+
+config CPU_LOONGSON3_CPUCFG_EMULATION
+ bool "Emulate the CPUCFG instruction on older Loongson cores"
+ default y
+ depends on CPU_LOONGSON64
+ help
+ Loongson-3A R4 and newer have the CPUCFG instruction available for
+ userland to query CPU capabilities, much like CPUID on x86. This
+ option provides emulation of the instruction on older Loongson
+ cores, back to Loongson-3A1000.
+
+ If unsure, please say Y.
+
config CPU_MIPS32_3_5_FEATURES
bool "MIPS32 Release 3.5 Features"
depends on SYS_HAS_CPU_MIPS32_R3_5
--
2.40.1



2024-01-27 19:51:45

by Jiaxun Yang

[permalink] [raw]
Subject: Re: [PATCH 1/1] MIPS: move unselectable entries out of the "CPU type" choice



在 2024/1/27 16:23, Masahiro Yamada 写道:
> Move the following entries out of the "CPU type" choice:
>
> - LOONGSON3_ENHANCEMENT
> - CPU_LOONGSON3_WORKAROUNDS
> - CPU_LOONGSON3_CPUCFG_EMULATION
>
> These entries cannot be selected from the choice because they depend on
> CPU_LOONGSON64, which is also located in the same choice.
>
> In fact, Kconfig does not consider them as choice values because they
> become children of CPU_LOOONGSON64 due to the automatic submenu creation
> in menu_finalize().
>
> However, it is hard to understand this behavior unless you are familiar
> with the Kconfig internals.
>
> "choice" should contain only selectable entries.
>
> Signed-off-by: Masahiro Yamada <[email protected]>
Reviewed-by: Jiaxun Yang <[email protected]>

Thanks!
> ---
>
> arch/mips/Kconfig | 76 +++++++++++++++++++++++------------------------
> 1 file changed, 38 insertions(+), 38 deletions(-)
>
> diff --git a/arch/mips/Kconfig b/arch/mips/Kconfig
> index 797ae590ebdb..a70b4f959fb1 100644
> --- a/arch/mips/Kconfig
> +++ b/arch/mips/Kconfig
> @@ -1269,44 +1269,6 @@ config CPU_LOONGSON64
> 3B1000, 3B1500, 3A2000, 3A3000 and 3A4000) processors. However, old
> Loongson-2E/2F is not covered here and will be removed in future.
>
> -config LOONGSON3_ENHANCEMENT
> - bool "New Loongson-3 CPU Enhancements"
> - default n
> - depends on CPU_LOONGSON64
> - help
> - New Loongson-3 cores (since Loongson-3A R2, as opposed to Loongson-3A
> - R1, Loongson-3B R1 and Loongson-3B R2) has many enhancements, such as
> - FTLB, L1-VCache, EI/DI/Wait/Prefetch instruction, DSP/DSPr2 ASE, User
> - Local register, Read-Inhibit/Execute-Inhibit, SFB (Store Fill Buffer),
> - Fast TLB refill support, etc.
> -
> - This option enable those enhancements which are not probed at run
> - time. If you want a generic kernel to run on all Loongson 3 machines,
> - please say 'N' here. If you want a high-performance kernel to run on
> - new Loongson-3 machines only, please say 'Y' here.
> -
> -config CPU_LOONGSON3_WORKAROUNDS
> - bool "Loongson-3 LLSC Workarounds"
> - default y if SMP
> - depends on CPU_LOONGSON64
> - help
> - Loongson-3 processors have the llsc issues which require workarounds.
> - Without workarounds the system may hang unexpectedly.
> -
> - Say Y, unless you know what you are doing.
> -
> -config CPU_LOONGSON3_CPUCFG_EMULATION
> - bool "Emulate the CPUCFG instruction on older Loongson cores"
> - default y
> - depends on CPU_LOONGSON64
> - help
> - Loongson-3A R4 and newer have the CPUCFG instruction available for
> - userland to query CPU capabilities, much like CPUID on x86. This
> - option provides emulation of the instruction on older Loongson
> - cores, back to Loongson-3A1000.
> -
> - If unsure, please say Y.
> -
> config CPU_LOONGSON2E
> bool "Loongson 2E"
> depends on SYS_HAS_CPU_LOONGSON2E
> @@ -1644,6 +1606,44 @@ config CPU_BMIPS
>
> endchoice
>
> +config LOONGSON3_ENHANCEMENT
> + bool "New Loongson-3 CPU Enhancements"
> + default n
> + depends on CPU_LOONGSON64
> + help
> + New Loongson-3 cores (since Loongson-3A R2, as opposed to Loongson-3A
> + R1, Loongson-3B R1 and Loongson-3B R2) has many enhancements, such as
> + FTLB, L1-VCache, EI/DI/Wait/Prefetch instruction, DSP/DSPr2 ASE, User
> + Local register, Read-Inhibit/Execute-Inhibit, SFB (Store Fill Buffer),
> + Fast TLB refill support, etc.
> +
> + This option enable those enhancements which are not probed at run
> + time. If you want a generic kernel to run on all Loongson 3 machines,
> + please say 'N' here. If you want a high-performance kernel to run on
> + new Loongson-3 machines only, please say 'Y' here.
> +
> +config CPU_LOONGSON3_WORKAROUNDS
> + bool "Loongson-3 LLSC Workarounds"
> + default y if SMP
> + depends on CPU_LOONGSON64
> + help
> + Loongson-3 processors have the llsc issues which require workarounds.
> + Without workarounds the system may hang unexpectedly.
> +
> + Say Y, unless you know what you are doing.
> +
> +config CPU_LOONGSON3_CPUCFG_EMULATION
> + bool "Emulate the CPUCFG instruction on older Loongson cores"
> + default y
> + depends on CPU_LOONGSON64
> + help
> + Loongson-3A R4 and newer have the CPUCFG instruction available for
> + userland to query CPU capabilities, much like CPUID on x86. This
> + option provides emulation of the instruction on older Loongson
> + cores, back to Loongson-3A1000.
> +
> + If unsure, please say Y.
> +
> config CPU_MIPS32_3_5_FEATURES
> bool "MIPS32 Release 3.5 Features"
> depends on SYS_HAS_CPU_MIPS32_R3_5

--
---
Jiaxun Yang


2024-02-20 13:50:53

by Thomas Bogendoerfer

[permalink] [raw]
Subject: Re: [PATCH 1/1] MIPS: move unselectable entries out of the "CPU type" choice

On Sun, Jan 28, 2024 at 01:23:09AM +0900, Masahiro Yamada wrote:
> Move the following entries out of the "CPU type" choice:
>
> - LOONGSON3_ENHANCEMENT
> - CPU_LOONGSON3_WORKAROUNDS
> - CPU_LOONGSON3_CPUCFG_EMULATION
>
> These entries cannot be selected from the choice because they depend on
> CPU_LOONGSON64, which is also located in the same choice.
>
> In fact, Kconfig does not consider them as choice values because they
> become children of CPU_LOOONGSON64 due to the automatic submenu creation
> in menu_finalize().
>
> However, it is hard to understand this behavior unless you are familiar
> with the Kconfig internals.
>
> "choice" should contain only selectable entries.
>
> Signed-off-by: Masahiro Yamada <[email protected]>
> ---
>
> arch/mips/Kconfig | 76 +++++++++++++++++++++++------------------------
> 1 file changed, 38 insertions(+), 38 deletions(-)

applied to mips-next.

Thomas.

--
Crap can work. Given enough thrust pigs will fly, but it's not necessarily a
good idea. [ RFC1925, 2.3 ]