[1/1] cmd: provide command sbi

Provide a command to display information about the SBI implementation.

The output might look like:

=> sbi
SBI 0.2
OpenSBI
Extensions:
  sbi_set_timer
  sbi_console_putchar
  sbi_console_getchar
  sbi_clear_ipi
  sbi_send_ipi
  sbi_remote_fence_i
  sbi_remote_sfence_vma
  sbi_remote_sfence_vma_asid
  sbi_shutdown
  SBI Base Functionality
  Timer Extension
  IPI Extension
  RFENCE Extension
  Hart State Management Extension

The command can be used to construct a unit test checking that the
communication with the SEE is working.

Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
---
 arch/riscv/include/asm/sbi.h |  2 +
 arch/riscv/lib/sbi.c         | 36 ++++++++++++++++
 cmd/Kconfig                  |  6 +++
 cmd/riscv/Makefile           |  1 +
 cmd/riscv/sbi.c              | 80 ++++++++++++++++++++++++++++++++++++
 5 files changed, 125 insertions(+)
 create mode 100644 cmd/riscv/sbi.c

--
2.28.0

On Sun, Aug 16, 2020 at 9:05 PM Heinrich Schuchardt <xypron.glpk@gmx.de> wrote:
>
> Provide a command to display information about the SBI implementation.
>
> The output might look like:
>
> => sbi
> SBI 0.2
> OpenSBI
> Extensions:
>   sbi_set_timer
>   sbi_console_putchar
>   sbi_console_getchar
>   sbi_clear_ipi
>   sbi_send_ipi
>   sbi_remote_fence_i
>   sbi_remote_sfence_vma
>   sbi_remote_sfence_vma_asid
>   sbi_shutdown
>   SBI Base Functionality
>   Timer Extension
>   IPI Extension
>   RFENCE Extension
>   Hart State Management Extension
>
> The command can be used to construct a unit test checking that the
> communication with the SEE is working.
>
> Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
> ---
>  arch/riscv/include/asm/sbi.h |  2 +
>  arch/riscv/lib/sbi.c         | 36 ++++++++++++++++
>  cmd/Kconfig                  |  6 +++
>  cmd/riscv/Makefile           |  1 +
>  cmd/riscv/sbi.c              | 80 ++++++++++++++++++++++++++++++++++++
>  5 files changed, 125 insertions(+)
>  create mode 100644 cmd/riscv/sbi.c
>
> diff --git a/arch/riscv/include/asm/sbi.h b/arch/riscv/include/asm/sbi.h
> index 08e1ac0c0e..53ca316180 100644
> --- a/arch/riscv/include/asm/sbi.h
> +++ b/arch/riscv/include/asm/sbi.h
> @@ -115,6 +115,8 @@ void sbi_remote_sfence_vma_asid(const unsigned long *hart_mask,
>                                 unsigned long asid);
>  #endif
>  void sbi_set_timer(uint64_t stime_value);
> +long sbi_get_spec_version(void);
> +int sbi_get_impl_id(void);
>  int sbi_probe_extension(int ext);
>
>  #endif
> diff --git a/arch/riscv/lib/sbi.c b/arch/riscv/lib/sbi.c
> index 8fbc23839d..920889ed13 100644
> --- a/arch/riscv/lib/sbi.c
> +++ b/arch/riscv/lib/sbi.c
> @@ -53,6 +53,42 @@ void sbi_set_timer(uint64_t stime_value)
>  #endif
>  }
>
> +/**
> + * sbi_get_spec_version() - get current SBI specification version
> + *
> + * Return: version id
> + */
> +long sbi_get_spec_version(void)
> +{
> +       struct sbiret ret;
> +
> +       ret = sbi_ecall(SBI_EXT_BASE, SBI_EXT_BASE_GET_SPEC_VERSION,
> +                       0, 0, 0, 0, 0, 0);
> +       if (!ret.error)
> +               if (ret.value)
> +                       return ret.value;
> +
> +       return -ENOTSUPP;
> +}
> +
> +/**
> + * sbi_get_impl_id() - get SBI implemenation ID
> + *
> + * Return: implementation ID
> + */
> +int sbi_get_impl_id(void)
> +{
> +       struct sbiret ret;
> +
> +       ret = sbi_ecall(SBI_EXT_BASE, SBI_EXT_BASE_GET_IMP_ID,
> +                       0, 0, 0, 0, 0, 0);
> +       if (!ret.error)
> +               if (ret.value)
> +                       return ret.value;
> +
> +       return -ENOTSUPP;
> +}
> +
>  /**
>   * sbi_probe_extension() - Check if an SBI extension ID is supported or not.
>   * @extid: The extension ID to be probed.
> diff --git a/cmd/Kconfig b/cmd/Kconfig
> index 23d7e27dc8..7a9fab51c5 100644
> --- a/cmd/Kconfig
> +++ b/cmd/Kconfig
> @@ -270,6 +270,12 @@ config SPL_CMD_TLV_EEPROM
>         help
>           Read system EEPROM data block in ONIE Tlvinfo format from SPL.
>
> +config CMD_SBI
> +       bool "SBI information"

nits: keeping the prompt to be the command name seems to be the
convention for other commands in U-Boot's Kconfig files, hence "sbi"

> +       depends on RISCV_SMODE

This should depend on SBI_V02 as well. Legacy SBI does not support
probing capabilities.

> +       help
> +         Display information about the SBI implementation.
> +
>  endmenu
>
>  menu "Boot commands"
> diff --git a/cmd/riscv/Makefile b/cmd/riscv/Makefile
> index 24df023ece..1e6ac364e3 100644
> --- a/cmd/riscv/Makefile
> +++ b/cmd/riscv/Makefile
> @@ -1,3 +1,4 @@
>  # SPDX-License-Identifier: GPL-2.0+
>
>  obj-$(CONFIG_CMD_EXCEPTION) += exception.o
> +obj-$(CONFIG_CMD_SBI) += sbi.o
> diff --git a/cmd/riscv/sbi.c b/cmd/riscv/sbi.c
> new file mode 100644
> index 0000000000..559d950ffb
> --- /dev/null
> +++ b/cmd/riscv/sbi.c
> @@ -0,0 +1,80 @@
> +// SPDX-License-Identifier: GPL-2.0+
> +/*
> + * The 'sbi' command displays information about the SBI implementation.
> + *
> + * Copyright (c) 2020, Heinrich Schuchardt <xypron.glpk@gmx.de>
> + */
> +
> +#include <common.h>
> +#include <command.h>
> +#include <asm/sbi.h>
> +
> +struct sbi_ext {
> +       const u32 id;
> +       const char *name;
> +};
> +
> +static struct sbi_ext extensions[] = {
> +       { 0x00000000, "sbi_set_timer" },
> +       { 0x00000001, "sbi_console_putchar" },
> +       { 0x00000002, "sbi_console_getchar" },
> +       { 0x00000003, "sbi_clear_ipi" },
> +       { 0x00000004, "sbi_send_ipi" },
> +       { 0x00000005, "sbi_remote_fence_i" },
> +       { 0x00000006, "sbi_remote_sfence_vma" },
> +       { 0x00000007, "sbi_remote_sfence_vma_asid" },
> +       { 0x00000008, "sbi_shutdown" },
> +       { 0x00000010, "SBI Base Functionality" },
> +       { 0x54494D45, "Timer Extension" },
> +       { 0x00735049, "IPI Extension" },
> +       { 0x52464E43, "RFENCE Extension" },
> +       { 0x0048534D, "Hart State Management Extension" },
> +};
> +
> +static int do_sbi(struct cmd_tbl *cmdtp, int flag, int argc,
> +                 char *const argv[])
> +{
> +       int i;
> +       long ret;
> +
> +       ret = sbi_get_spec_version();
> +       if (ret >= 0)
> +               printf("SBI %ld.%ld\n", ret >> 24, ret &0xffffff);
> +       ret = sbi_get_impl_id();
> +       if (ret >= 0) {
> +               switch (ret) {
> +               case 0:
> +                       printf("Berkeley Boot Loader (BBL)\n");
> +                       break;
> +               case 1:
> +                       printf("OpenSBI\n");
> +                       break;
> +               case 2:
> +                       printf("Xvisor\n");
> +                       break;
> +               case 3:
> +                       printf("KVM\n");
> +                       break;
> +               default:
> +                       printf("Unknown implementation\n");
> +                       break;
> +               }
> +       }
> +       printf("Extensions:\n");
> +       for (i = 0; i < ARRAY_SIZE(extensions); ++i) {
> +               ret = sbi_probe_extension(extensions[i].id);
> +               if (ret > 0)
> +                       printf("  %s\n", extensions[i].name);
> +       }
> +       return 0;
> +}
> +
> +#ifdef CONFIG_SYS_LONGHELP
> +static char sbi_help_text[] = "";

Nothing is displayed for LONGHELP? Or we just remove this?

> +#endif
> +
> +U_BOOT_CMD_COMPLETE(
> +       sbi, 2, 0, do_sbi,
> +       "display SBI information",
> +       sbi_help_text, NULL
> +);

Regards,
Bin

On 18.08.20 10:57, Bin Meng wrote:
> On Sun, Aug 16, 2020 at 9:05 PM Heinrich Schuchardt <xypron.glpk@gmx.de> wrote:
>>
>> Provide a command to display information about the SBI implementation.
>>
>> The output might look like:
>>
>> => sbi
>> SBI 0.2
>> OpenSBI
>> Extensions:
>>   sbi_set_timer
>>   sbi_console_putchar
>>   sbi_console_getchar
>>   sbi_clear_ipi
>>   sbi_send_ipi
>>   sbi_remote_fence_i
>>   sbi_remote_sfence_vma
>>   sbi_remote_sfence_vma_asid
>>   sbi_shutdown
>>   SBI Base Functionality
>>   Timer Extension
>>   IPI Extension
>>   RFENCE Extension
>>   Hart State Management Extension
>>
>> The command can be used to construct a unit test checking that the
>> communication with the SEE is working.
>>
>> Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
>> ---
>>  arch/riscv/include/asm/sbi.h |  2 +
>>  arch/riscv/lib/sbi.c         | 36 ++++++++++++++++
>>  cmd/Kconfig                  |  6 +++
>>  cmd/riscv/Makefile           |  1 +
>>  cmd/riscv/sbi.c              | 80 ++++++++++++++++++++++++++++++++++++
>>  5 files changed, 125 insertions(+)
>>  create mode 100644 cmd/riscv/sbi.c
>>
>> diff --git a/arch/riscv/include/asm/sbi.h b/arch/riscv/include/asm/sbi.h
>> index 08e1ac0c0e..53ca316180 100644
>> --- a/arch/riscv/include/asm/sbi.h
>> +++ b/arch/riscv/include/asm/sbi.h
>> @@ -115,6 +115,8 @@ void sbi_remote_sfence_vma_asid(const unsigned long *hart_mask,
>>                                 unsigned long asid);
>>  #endif
>>  void sbi_set_timer(uint64_t stime_value);
>> +long sbi_get_spec_version(void);
>> +int sbi_get_impl_id(void);
>>  int sbi_probe_extension(int ext);
>>
>>  #endif
>> diff --git a/arch/riscv/lib/sbi.c b/arch/riscv/lib/sbi.c
>> index 8fbc23839d..920889ed13 100644
>> --- a/arch/riscv/lib/sbi.c
>> +++ b/arch/riscv/lib/sbi.c
>> @@ -53,6 +53,42 @@ void sbi_set_timer(uint64_t stime_value)
>>  #endif
>>  }
>>
>> +/**
>> + * sbi_get_spec_version() - get current SBI specification version
>> + *
>> + * Return: version id
>> + */
>> +long sbi_get_spec_version(void)
>> +{
>> +       struct sbiret ret;
>> +
>> +       ret = sbi_ecall(SBI_EXT_BASE, SBI_EXT_BASE_GET_SPEC_VERSION,
>> +                       0, 0, 0, 0, 0, 0);
>> +       if (!ret.error)
>> +               if (ret.value)
>> +                       return ret.value;
>> +
>> +       return -ENOTSUPP;
>> +}
>> +
>> +/**
>> + * sbi_get_impl_id() - get SBI implemenation ID
>> + *
>> + * Return: implementation ID
>> + */
>> +int sbi_get_impl_id(void)
>> +{
>> +       struct sbiret ret;
>> +
>> +       ret = sbi_ecall(SBI_EXT_BASE, SBI_EXT_BASE_GET_IMP_ID,
>> +                       0, 0, 0, 0, 0, 0);
>> +       if (!ret.error)
>> +               if (ret.value)
>> +                       return ret.value;
>> +
>> +       return -ENOTSUPP;
>> +}
>> +
>>  /**
>>   * sbi_probe_extension() - Check if an SBI extension ID is supported or not.
>>   * @extid: The extension ID to be probed.
>> diff --git a/cmd/Kconfig b/cmd/Kconfig
>> index 23d7e27dc8..7a9fab51c5 100644
>> --- a/cmd/Kconfig
>> +++ b/cmd/Kconfig
>> @@ -270,6 +270,12 @@ config SPL_CMD_TLV_EEPROM
>>         help
>>           Read system EEPROM data block in ONIE Tlvinfo format from SPL.
>>
>> +config CMD_SBI
>> +       bool "SBI information"
>
> nits: keeping the prompt to be the command name seems to be the
> convention for other commands in U-Boot's Kconfig files, hence "sbi"
>
>> +       depends on RISCV_SMODE
>
> This should depend on SBI_V02 as well. Legacy SBI does not support
> probing capabilities.
>
>> +       help
>> +         Display information about the SBI implementation.
>> +
>>  endmenu
>>
>>  menu "Boot commands"
>> diff --git a/cmd/riscv/Makefile b/cmd/riscv/Makefile
>> index 24df023ece..1e6ac364e3 100644
>> --- a/cmd/riscv/Makefile
>> +++ b/cmd/riscv/Makefile
>> @@ -1,3 +1,4 @@
>>  # SPDX-License-Identifier: GPL-2.0+
>>
>>  obj-$(CONFIG_CMD_EXCEPTION) += exception.o
>> +obj-$(CONFIG_CMD_SBI) += sbi.o
>> diff --git a/cmd/riscv/sbi.c b/cmd/riscv/sbi.c
>> new file mode 100644
>> index 0000000000..559d950ffb
>> --- /dev/null
>> +++ b/cmd/riscv/sbi.c
>> @@ -0,0 +1,80 @@
>> +// SPDX-License-Identifier: GPL-2.0+
>> +/*
>> + * The 'sbi' command displays information about the SBI implementation.
>> + *
>> + * Copyright (c) 2020, Heinrich Schuchardt <xypron.glpk@gmx.de>
>> + */
>> +
>> +#include <common.h>
>> +#include <command.h>
>> +#include <asm/sbi.h>
>> +
>> +struct sbi_ext {
>> +       const u32 id;
>> +       const char *name;
>> +};
>> +
>> +static struct sbi_ext extensions[] = {
>> +       { 0x00000000, "sbi_set_timer" },
>> +       { 0x00000001, "sbi_console_putchar" },
>> +       { 0x00000002, "sbi_console_getchar" },
>> +       { 0x00000003, "sbi_clear_ipi" },
>> +       { 0x00000004, "sbi_send_ipi" },
>> +       { 0x00000005, "sbi_remote_fence_i" },
>> +       { 0x00000006, "sbi_remote_sfence_vma" },
>> +       { 0x00000007, "sbi_remote_sfence_vma_asid" },
>> +       { 0x00000008, "sbi_shutdown" },
>> +       { 0x00000010, "SBI Base Functionality" },
>> +       { 0x54494D45, "Timer Extension" },
>> +       { 0x00735049, "IPI Extension" },
>> +       { 0x52464E43, "RFENCE Extension" },
>> +       { 0x0048534D, "Hart State Management Extension" },
>> +};
>> +
>> +static int do_sbi(struct cmd_tbl *cmdtp, int flag, int argc,
>> +                 char *const argv[])
>> +{
>> +       int i;
>> +       long ret;
>> +
>> +       ret = sbi_get_spec_version();
>> +       if (ret >= 0)
>> +               printf("SBI %ld.%ld\n", ret >> 24, ret &0xffffff);
>> +       ret = sbi_get_impl_id();
>> +       if (ret >= 0) {
>> +               switch (ret) {
>> +               case 0:
>> +                       printf("Berkeley Boot Loader (BBL)\n");
>> +                       break;
>> +               case 1:
>> +                       printf("OpenSBI\n");
>> +                       break;
>> +               case 2:
>> +                       printf("Xvisor\n");
>> +                       break;
>> +               case 3:
>> +                       printf("KVM\n");
>> +                       break;
>> +               default:
>> +                       printf("Unknown implementation\n");
>> +                       break;
>> +               }
>> +       }
>> +       printf("Extensions:\n");
>> +       for (i = 0; i < ARRAY_SIZE(extensions); ++i) {
>> +               ret = sbi_probe_extension(extensions[i].id);
>> +               if (ret > 0)
>> +                       printf("  %s\n", extensions[i].name);
>> +       }
>> +       return 0;
>> +}
>> +
>> +#ifdef CONFIG_SYS_LONGHELP
>> +static char sbi_help_text[] = "";
>
> Nothing is displayed for LONGHELP? Or we just remove this?

With sbi_help_text = "":

=> help sbi
sbi - display SBI information

Usage:
sbi



With sbi_help_text = NULL:

=> help sbi
sbi - display SBI information

Usage:
sbi - No additional help available.



As there are no arguments foreseen for the sbi command I find this "No
additional help available" irritating.

This is why I am passing "" as help value.

Best regards

Heinrich

>
>> +#endif
>> +
>> +U_BOOT_CMD_COMPLETE(
>> +       sbi, 2, 0, do_sbi,
>> +       "display SBI information",
>> +       sbi_help_text, NULL
>> +);
>
> Regards,
> Bin
>

On Tue, Aug 18, 2020 at 5:16 PM Heinrich Schuchardt <xypron.glpk@gmx.de> wrote:
>
> On 18.08.20 10:57, Bin Meng wrote:
> > On Sun, Aug 16, 2020 at 9:05 PM Heinrich Schuchardt <xypron.glpk@gmx.de> wrote:
> >>
> >> Provide a command to display information about the SBI implementation.
> >>
> >> The output might look like:
> >>
> >> => sbi
> >> SBI 0.2
> >> OpenSBI
> >> Extensions:
> >>   sbi_set_timer
> >>   sbi_console_putchar
> >>   sbi_console_getchar
> >>   sbi_clear_ipi
> >>   sbi_send_ipi
> >>   sbi_remote_fence_i
> >>   sbi_remote_sfence_vma
> >>   sbi_remote_sfence_vma_asid
> >>   sbi_shutdown
> >>   SBI Base Functionality
> >>   Timer Extension
> >>   IPI Extension
> >>   RFENCE Extension
> >>   Hart State Management Extension
> >>
> >> The command can be used to construct a unit test checking that the
> >> communication with the SEE is working.
> >>
> >> Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
> >> ---
> >>  arch/riscv/include/asm/sbi.h |  2 +
> >>  arch/riscv/lib/sbi.c         | 36 ++++++++++++++++
> >>  cmd/Kconfig                  |  6 +++
> >>  cmd/riscv/Makefile           |  1 +
> >>  cmd/riscv/sbi.c              | 80 ++++++++++++++++++++++++++++++++++++
> >>  5 files changed, 125 insertions(+)
> >>  create mode 100644 cmd/riscv/sbi.c
> >>
> >> diff --git a/arch/riscv/include/asm/sbi.h b/arch/riscv/include/asm/sbi.h
> >> index 08e1ac0c0e..53ca316180 100644
> >> --- a/arch/riscv/include/asm/sbi.h
> >> +++ b/arch/riscv/include/asm/sbi.h
> >> @@ -115,6 +115,8 @@ void sbi_remote_sfence_vma_asid(const unsigned long *hart_mask,
> >>                                 unsigned long asid);
> >>  #endif
> >>  void sbi_set_timer(uint64_t stime_value);
> >> +long sbi_get_spec_version(void);
> >> +int sbi_get_impl_id(void);
> >>  int sbi_probe_extension(int ext);
> >>
> >>  #endif
> >> diff --git a/arch/riscv/lib/sbi.c b/arch/riscv/lib/sbi.c
> >> index 8fbc23839d..920889ed13 100644
> >> --- a/arch/riscv/lib/sbi.c
> >> +++ b/arch/riscv/lib/sbi.c
> >> @@ -53,6 +53,42 @@ void sbi_set_timer(uint64_t stime_value)
> >>  #endif
> >>  }
> >>
> >> +/**
> >> + * sbi_get_spec_version() - get current SBI specification version
> >> + *
> >> + * Return: version id
> >> + */
> >> +long sbi_get_spec_version(void)
> >> +{
> >> +       struct sbiret ret;
> >> +
> >> +       ret = sbi_ecall(SBI_EXT_BASE, SBI_EXT_BASE_GET_SPEC_VERSION,
> >> +                       0, 0, 0, 0, 0, 0);
> >> +       if (!ret.error)
> >> +               if (ret.value)
> >> +                       return ret.value;
> >> +
> >> +       return -ENOTSUPP;
> >> +}
> >> +
> >> +/**
> >> + * sbi_get_impl_id() - get SBI implemenation ID
> >> + *
> >> + * Return: implementation ID
> >> + */
> >> +int sbi_get_impl_id(void)
> >> +{
> >> +       struct sbiret ret;
> >> +
> >> +       ret = sbi_ecall(SBI_EXT_BASE, SBI_EXT_BASE_GET_IMP_ID,
> >> +                       0, 0, 0, 0, 0, 0);
> >> +       if (!ret.error)
> >> +               if (ret.value)
> >> +                       return ret.value;
> >> +
> >> +       return -ENOTSUPP;
> >> +}
> >> +
> >>  /**
> >>   * sbi_probe_extension() - Check if an SBI extension ID is supported or not.
> >>   * @extid: The extension ID to be probed.
> >> diff --git a/cmd/Kconfig b/cmd/Kconfig
> >> index 23d7e27dc8..7a9fab51c5 100644
> >> --- a/cmd/Kconfig
> >> +++ b/cmd/Kconfig
> >> @@ -270,6 +270,12 @@ config SPL_CMD_TLV_EEPROM
> >>         help
> >>           Read system EEPROM data block in ONIE Tlvinfo format from SPL.
> >>
> >> +config CMD_SBI
> >> +       bool "SBI information"
> >
> > nits: keeping the prompt to be the command name seems to be the
> > convention for other commands in U-Boot's Kconfig files, hence "sbi"
> >
> >> +       depends on RISCV_SMODE
> >
> > This should depend on SBI_V02 as well. Legacy SBI does not support
> > probing capabilities.
> >
> >> +       help
> >> +         Display information about the SBI implementation.
> >> +
> >>  endmenu
> >>
> >>  menu "Boot commands"
> >> diff --git a/cmd/riscv/Makefile b/cmd/riscv/Makefile
> >> index 24df023ece..1e6ac364e3 100644
> >> --- a/cmd/riscv/Makefile
> >> +++ b/cmd/riscv/Makefile
> >> @@ -1,3 +1,4 @@
> >>  # SPDX-License-Identifier: GPL-2.0+
> >>
> >>  obj-$(CONFIG_CMD_EXCEPTION) += exception.o
> >> +obj-$(CONFIG_CMD_SBI) += sbi.o
> >> diff --git a/cmd/riscv/sbi.c b/cmd/riscv/sbi.c
> >> new file mode 100644
> >> index 0000000000..559d950ffb
> >> --- /dev/null
> >> +++ b/cmd/riscv/sbi.c
> >> @@ -0,0 +1,80 @@
> >> +// SPDX-License-Identifier: GPL-2.0+
> >> +/*
> >> + * The 'sbi' command displays information about the SBI implementation.
> >> + *
> >> + * Copyright (c) 2020, Heinrich Schuchardt <xypron.glpk@gmx.de>
> >> + */
> >> +
> >> +#include <common.h>
> >> +#include <command.h>
> >> +#include <asm/sbi.h>
> >> +
> >> +struct sbi_ext {
> >> +       const u32 id;
> >> +       const char *name;
> >> +};
> >> +
> >> +static struct sbi_ext extensions[] = {
> >> +       { 0x00000000, "sbi_set_timer" },
> >> +       { 0x00000001, "sbi_console_putchar" },
> >> +       { 0x00000002, "sbi_console_getchar" },
> >> +       { 0x00000003, "sbi_clear_ipi" },
> >> +       { 0x00000004, "sbi_send_ipi" },
> >> +       { 0x00000005, "sbi_remote_fence_i" },
> >> +       { 0x00000006, "sbi_remote_sfence_vma" },
> >> +       { 0x00000007, "sbi_remote_sfence_vma_asid" },
> >> +       { 0x00000008, "sbi_shutdown" },
> >> +       { 0x00000010, "SBI Base Functionality" },
> >> +       { 0x54494D45, "Timer Extension" },
> >> +       { 0x00735049, "IPI Extension" },
> >> +       { 0x52464E43, "RFENCE Extension" },
> >> +       { 0x0048534D, "Hart State Management Extension" },
> >> +};
> >> +
> >> +static int do_sbi(struct cmd_tbl *cmdtp, int flag, int argc,
> >> +                 char *const argv[])
> >> +{
> >> +       int i;
> >> +       long ret;
> >> +
> >> +       ret = sbi_get_spec_version();
> >> +       if (ret >= 0)
> >> +               printf("SBI %ld.%ld\n", ret >> 24, ret &0xffffff);
> >> +       ret = sbi_get_impl_id();
> >> +       if (ret >= 0) {
> >> +               switch (ret) {
> >> +               case 0:
> >> +                       printf("Berkeley Boot Loader (BBL)\n");
> >> +                       break;
> >> +               case 1:
> >> +                       printf("OpenSBI\n");
> >> +                       break;
> >> +               case 2:
> >> +                       printf("Xvisor\n");
> >> +                       break;
> >> +               case 3:
> >> +                       printf("KVM\n");
> >> +                       break;
> >> +               default:
> >> +                       printf("Unknown implementation\n");
> >> +                       break;
> >> +               }
> >> +       }
> >> +       printf("Extensions:\n");
> >> +       for (i = 0; i < ARRAY_SIZE(extensions); ++i) {
> >> +               ret = sbi_probe_extension(extensions[i].id);
> >> +               if (ret > 0)
> >> +                       printf("  %s\n", extensions[i].name);
> >> +       }
> >> +       return 0;
> >> +}
> >> +
> >> +#ifdef CONFIG_SYS_LONGHELP
> >> +static char sbi_help_text[] = "";
> >
> > Nothing is displayed for LONGHELP? Or we just remove this?
>
> With sbi_help_text = "":
>
> => help sbi
> sbi - display SBI information
>
> Usage:
> sbi
>
>
>
> With sbi_help_text = NULL:
>
> => help sbi
> sbi - display SBI information
>
> Usage:
> sbi - No additional help available.
>
>
>
> As there are no arguments foreseen for the sbi command I find this "No
> additional help available" irritating.

Maybe we should put a more detailed help message on what this command
is for, so that this LONGHELP can be really helpful.

>
> This is why I am passing "" as help value.
>

Regards,
Bin