RE: [PATCH v1 2/2] mlxbf-bootctl: Support setting the ARM boot state to "OS up"

[Vadim Pasternak]

> -----Original Message-----
> From: Asmaa Mnebhi <asmaa@xxxxxxxxxx>
> Sent: Wednesday, 9 August 2023 17:15
> To: markgross@xxxxxxxxxx; Vadim Pasternak <vadimp@xxxxxxxxxx>;
> hdegoede@xxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx
> Cc: Asmaa Mnebhi <asmaa@xxxxxxxxxx>
> Subject: [PATCH v1 2/2] mlxbf-bootctl: Support setting the ARM boot state to
> "OS up"
> 
> The BlueField has internal registers to store the ARM boot states.
> Support setting the BlueField ARM boot state to "OS up".
> 
> Signed-off-by: Asmaa Mnebhi <asmaa@xxxxxxxxxx>

Reviewed-by: Vadim Pasternak <vadimp@xxxxxxxxxx>

> ---
>  drivers/platform/mellanox/mlxbf-bootctl.c | 25 +++++++++++++++++++++++
> drivers/platform/mellanox/mlxbf-bootctl.h |  5 +++++
>  2 files changed, 30 insertions(+)
> 
> diff --git a/drivers/platform/mellanox/mlxbf-bootctl.c
> b/drivers/platform/mellanox/mlxbf-bootctl.c
> index 3ea11250b681..7a67fcc6dd98 100644
> --- a/drivers/platform/mellanox/mlxbf-bootctl.c
> +++ b/drivers/platform/mellanox/mlxbf-bootctl.c
> @@ -80,6 +80,7 @@ static const char * const mlxbf_rsh_log_level[] = {
>  	"INFO", "WARN", "ERR", "ASSERT"};
> 
>  static DEFINE_MUTEX(icm_ops_lock);
> +static DEFINE_MUTEX(os_up_lock);
> 
>  /* ARM SMC call which is atomic and no need for lock. */  static int
> mlxbf_bootctl_smc(unsigned int smc_op, int smc_arg) @@ -431,6 +432,28
> @@ static ssize_t large_icm_store(struct device *dev,
>  	return res.a0 ? -EPERM : count;
>  }
> 
> +static ssize_t os_up_store(struct device *dev,
> +			   struct device_attribute *attr,
> +			   const char *buf, size_t count)
> +{
> +	struct arm_smccc_res res;
> +	unsigned long val;
> +	int err;
> +
> +	err = kstrtoul(buf, 10, &val);
> +	if (err)
> +		return err;
> +
> +	if (val != 1)
> +		return -EINVAL;
> +
> +	mutex_lock(&os_up_lock);
> +	arm_smccc_smc(MLNX_HANDLE_OS_UP, 0, 0, 0, 0, 0, 0, 0, &res);
> +	mutex_unlock(&os_up_lock);
> +
> +	return count;
> +}
> +
>  static DEVICE_ATTR_RW(post_reset_wdog);  static
> DEVICE_ATTR_RW(reset_action);  static
> DEVICE_ATTR_RW(second_reset_action);
> @@ -439,6 +462,7 @@ static DEVICE_ATTR_RO(secure_boot_fuse_state);
>  static DEVICE_ATTR_WO(fw_reset);
>  static DEVICE_ATTR_WO(rsh_log);
>  static DEVICE_ATTR_RW(large_icm);
> +static DEVICE_ATTR_WO(os_up);
> 
>  static struct attribute *mlxbf_bootctl_attrs[] = {
>  	&dev_attr_post_reset_wdog.attr,
> @@ -449,6 +473,7 @@ static struct attribute *mlxbf_bootctl_attrs[] = {
>  	&dev_attr_fw_reset.attr,
>  	&dev_attr_rsh_log.attr,
>  	&dev_attr_large_icm.attr,
> +	&dev_attr_os_up.attr,
>  	NULL
>  };
> 
> diff --git a/drivers/platform/mellanox/mlxbf-bootctl.h
> b/drivers/platform/mellanox/mlxbf-bootctl.h
> index 75d59ade92be..19142cc71312 100644
> --- a/drivers/platform/mellanox/mlxbf-bootctl.h
> +++ b/drivers/platform/mellanox/mlxbf-bootctl.h
> @@ -90,6 +90,11 @@
> 
>  #define MAX_ICM_BUFFER_SIZE 10
> 
> +/*
> + * SMC function ID to set the ARM boot state to up  */
> +#define MLNX_HANDLE_OS_UP    0x82000014
> +
>  /* SMC function IDs for SiP Service queries */
>  #define MLXBF_BOOTCTL_SIP_SVC_CALL_COUNT	0x8200ff00
>  #define MLXBF_BOOTCTL_SIP_SVC_UID		0x8200ff01
> --
> 2.30.1