[PATCH] sbi: fwft: clear the config lock when warm boot

[Xiang W <wxjstz@126.com>]

? 2024-11-15?? 15:33 +0800?Nick Hu???
> The hotplug cpu should clear the fwft config's SBI_FWFT_SET_FLAG_LOCK
> in the warm boot flow otherwise the cpu can't set the menvcfg.sse by
> SBI_EXT_FWFT_SET sbi call and cause the illegal instruction when
> accessing the CSR_SSP in kernel.
> 
> Signed-off-by: Nick Hu <nick.hu@sifive.com>

In sbi_fwft_init, the memory for fwft_hart_state is allocated by?
sbi_zalloc, which ensures that flags is 0. So no additional code
is needed to clear the SBI_FWFT_SET_FLAG_LOCK bit.

Regards,
Xiang W
> ---
> ?lib/sbi/sbi_fwft.c | 15 +++++++++++++++
> ?1 file changed, 15 insertions(+)
> 
> diff --git a/lib/sbi/sbi_fwft.c b/lib/sbi/sbi_fwft.c
> index 9cf14c16..0cb165b4 100644
> --- a/lib/sbi/sbi_fwft.c
> +++ b/lib/sbi/sbi_fwft.c
> @@ -311,6 +311,18 @@ static int fwft_get_feature(enum sbi_fwft_feature_t feature,
> ?	return SBI_SUCCESS;
> ?}
> ?
> +static void fwft_clear_config_lock(enum sbi_fwft_feature_t feature)
> +{
> +	int ret;
> +	struct fwft_config *conf;
> +
> +	ret = fwft_get_feature(feature, &conf);
> +	if (ret)
> +		return;
> +
> +	conf->flags &= ~SBI_FWFT_SET_FLAG_LOCK;
> +}
> +
> ?int sbi_fwft_set(enum sbi_fwft_feature_t feature, unsigned long value,
> ?		 unsigned long flags)
> ?{
> @@ -414,5 +426,8 @@ int sbi_fwft_init(struct sbi_scratch *scratch, bool cold_boot)
> ?		fwft_set_hart_state_ptr(scratch, fhs);
> ?	}
> ?
> +	for (i = 0; i < array_size(features); i++)
> +		fwft_clear_config_lock(features[i].id);
> +
> ?	return 0;
> ?}
> -- 
> 2.34.1
> 
>