[PATCH v2 5/6] lib: sbi: implement firmware feature SBI_FWFT_DOUBLE_TRAP

[Clément Léger]

On 13/09/2024 20:11, Samuel Holland wrote:
> On 2024-09-13 9:34 AM, Clément Léger wrote:
>> Add support for double trap firmware feature.
>>
>> Link: https://lists.riscv.org/g/tech-prs/message/985 [1]
>> Signed-off-by: Clément Léger <cleger at rivosinc.com>
>> ---
>>  include/sbi/riscv_encoding.h |  3 ++-
>>  lib/sbi/sbi_fwft.c           | 25 +++++++++++++++++++++++++
>>  2 files changed, 27 insertions(+), 1 deletion(-)
>>
>> diff --git a/include/sbi/riscv_encoding.h b/include/sbi/riscv_encoding.h
>> index 5b3bbc5..1d83434 100644
>> --- a/include/sbi/riscv_encoding.h
>> +++ b/include/sbi/riscv_encoding.h
>> @@ -214,7 +214,8 @@
>>  #define ENVCFG_ADUE_SHIFT		61
>>  #define ENVCFG_ADUE			(_ULL(1) << ENVCFG_ADUE_SHIFT)
>>  #define ENVCFG_CDE			(_ULL(1) << 60)
>> -#define ENVCFG_DTE			(_ULL(1) << 59)
>> +#define ENVCFG_DTE_SHIFT		59
>> +#define ENVCFG_DTE			(_ULL(1) << ENVCFG_DTE_SHIFT)
>>  #define ENVCFG_CBZE			(_UL(1) << 7)
>>  #define ENVCFG_CBCFE			(_UL(1) << 6)
>>  #define ENVCFG_CBIE_SHIFT		4
>> diff --git a/lib/sbi/sbi_fwft.c b/lib/sbi/sbi_fwft.c
>> index c818afd..39bd592 100644
>> --- a/lib/sbi/sbi_fwft.c
>> +++ b/lib/sbi/sbi_fwft.c
>> @@ -155,6 +155,25 @@ static int fwft_get_adue(struct fwft_config *conf, unsigned long *value)
>>  	return fwft_menvcfg_read_bit(value, ENVCFG_ADUE_SHIFT);
>>  }
>>  
>> +static int fwft_double_trap_supported(struct fwft_config *conf)
>> +{
>> +	if (!sbi_hart_has_extension(sbi_scratch_thishart_ptr(),
>> +				    SBI_HART_EXT_SSDBLTRP))
>> +		return SBI_ENOTSUPP;
>> +
>> +	return SBI_OK;
>> +}
>> +
>> +static int fwft_set_double_trap(struct fwft_config *conf, unsigned long value)
>> +{
>> +	return fwft_menvcfg_set_bit(value, ENVCFG_DTE_SHIFT);
>> +}
>> +
>> +static int fwft_get_double_trap(struct fwft_config *conf, unsigned long *value)
>> +{
>> +	return fwft_menvcfg_read_bit(value, ENVCFG_DTE_SHIFT);
>> +}
>> +
> 
> nit: to be sorted, these functions should go above fwft_adue_supported(). But
> it's a trivial concern, so:

Oh damn, I sorted the entries but not the functions. No worries, I'll
resend a V3.

Thanks,

Clément

> 
> Reviewed-by: Samuel Holland <samuel.holland at sifive.com>
> 
>>  static struct fwft_config* get_feature_config(enum sbi_fwft_feature_t feature)
>>  {
>>  	int i;
>> @@ -240,6 +259,12 @@ static const struct fwft_feature features[] =
>>  		.set = fwft_set_misaligned_delegation,
>>  		.get = fwft_get_misaligned_delegation,
>>  	},
>> +	{
>> +		.id = SBI_FWFT_DOUBLE_TRAP,
>> +		.supported = fwft_double_trap_supported,
>> +		.set = fwft_set_double_trap,
>> +		.get = fwft_get_double_trap,
>> +	},
>>  	{
>>  		.id = SBI_FWFT_PTE_AD_HW_UPDATING,
>>  		.supported = fwft_adue_supported,
>