RE: [PATCH v2 2/5] firmware: arm_scmi: Make use SCMI v2.0 fastchannel for performance protocol

[Peng Fan]

> Subject: [PATCH v2 2/5] firmware: arm_scmi: Make use SCMI v2.0
> fastchannel for performance protocol
> 
> SCMI v2.0 adds support for "FastChannel" which do not use a message
> header as they are specialized for a single message.
> 
> Only PERFORMANCE_LIMITS_{SET,GET} and
> PERFORMANCE_LEVEL_{SET,GET} commands are supported over
> fastchannels. As they are optional, they need to be discovered by
> PERFORMANCE_DESCRIBE_FASTCHANNEL command.
> Further {LIMIT,LEVEL}_SET commands can have optional doorbell support.
> 
> Add support for making use of these fastchannels.
> 
> Cc: Ionela Voinescu <Ionela.Voinescu@xxxxxxx>
> Cc: Chris Redpath <Chris.Redpath@xxxxxxx>
> Cc: Quentin Perret <Quentin.Perret@xxxxxxx>
> Signed-off-by: Sudeep Holla <sudeep.holla@xxxxxxx>
> ---
>  drivers/firmware/arm_scmi/perf.c | 104
> +++++++++++++++++++++++++++++--
>  1 file changed, 100 insertions(+), 4 deletions(-)
> 
> v1->v2:
> 	- Changed the macro SCMI_PERF_FC_RING_DB to use do {} while(0)
> 
> diff --git a/drivers/firmware/arm_scmi/perf.c
> b/drivers/firmware/arm_scmi/perf.c
> index 6cce3e82e81e..fb7f6cab2c11 100644
> --- a/drivers/firmware/arm_scmi/perf.c
> +++ b/drivers/firmware/arm_scmi/perf.c
> @@ -8,6 +8,7 @@
>  #include <linux/bits.h>
>  #include <linux/of.h>
>  #include <linux/io.h>
> +#include <linux/io-64-nonatomic-hi-lo.h>
>  #include <linux/platform_device.h>
>  #include <linux/pm_opp.h>
>  #include <linux/sort.h>
> @@ -293,7 +294,42 @@ scmi_perf_describe_levels_get(const struct
> scmi_handle *handle, u32 domain,
>  	return ret;
>  }
> 
> -static int scmi_perf_limits_set(const struct scmi_handle *handle, u32
> domain,
> +#define SCMI_PERF_FC_RING_DB(doorbell, w)		\
> +do {							\
> +	u##w val = 0;					\
> +	struct scmi_fc_db_info *db = doorbell;		\
> +							\
> +	if (db->mask)					\
> +		val = ioread##w(db->addr) & db->mask;	\
> +	iowrite##w((u##w)db->set | val, db->addr);	\
> +} while(0)
> +
> +static void scmi_perf_fc_ring_db(struct scmi_fc_db_info *db) {
> +	if (!db || !db->addr)
> +		return;
> +
> +	if (db->width == 1)
> +		SCMI_PERF_FC_RING_DB(db, 8);
> +	else if (db->width == 2)
> +		SCMI_PERF_FC_RING_DB(db, 16);
> +	else if (db->width == 4)
> +		SCMI_PERF_FC_RING_DB(db, 32);
> +	else /* db->width == 8 */
> +#ifdef CONFIG_64BIT
> +		SCMI_PERF_FC_RING_DB(db, 64);
> +#else
> +	{
> +		u64 val = 0;
> +
> +		if (db->mask)
> +			val = ioread64_hi_lo(db->addr) & db->mask;
> +		iowrite64_hi_lo(db->set, db->addr);
> +	}
> +#endif
> +}
> +
> +static int scmi_perf_mb_limits_set(const struct scmi_handle *handle,
> +u32 domain,
>  				   u32 max_perf, u32 min_perf)
>  {
>  	int ret;
> @@ -316,7 +352,23 @@ static int scmi_perf_limits_set(const struct
> scmi_handle *handle, u32 domain,
>  	return ret;
>  }
> 
> -static int scmi_perf_limits_get(const struct scmi_handle *handle, u32
> domain,
> +static int scmi_perf_limits_set(const struct scmi_handle *handle, u32
> domain,
> +				u32 max_perf, u32 min_perf)
> +{
> +	struct scmi_perf_info *pi = handle->perf_priv;
> +	struct perf_dom_info *dom = pi->dom_info + domain;
> +
> +	if (dom->fc_info && dom->fc_info->limit_set_addr) {
> +		iowrite32(max_perf, dom->fc_info->limit_set_addr);
> +		iowrite32(min_perf, dom->fc_info->limit_set_addr + 4);
> +		scmi_perf_fc_ring_db(dom->fc_info->limit_set_db);
> +		return 0;
> +	}
> +
> +	return scmi_perf_mb_limits_set(handle, domain, max_perf, min_perf); }
> +
> +static int scmi_perf_mb_limits_get(const struct scmi_handle *handle,
> +u32 domain,
>  				   u32 *max_perf, u32 *min_perf)
>  {
>  	int ret;
> @@ -342,7 +394,22 @@ static int scmi_perf_limits_get(const struct
> scmi_handle *handle, u32 domain,
>  	return ret;
>  }
> 
> -static int scmi_perf_level_set(const struct scmi_handle *handle, u32 domain,
> +static int scmi_perf_limits_get(const struct scmi_handle *handle, u32
> domain,
> +				u32 *max_perf, u32 *min_perf)
> +{
> +	struct scmi_perf_info *pi = handle->perf_priv;
> +	struct perf_dom_info *dom = pi->dom_info + domain;
> +
> +	if (dom->fc_info && dom->fc_info->limit_get_addr) {
> +		*max_perf = ioread32(dom->fc_info->limit_get_addr);
> +		*min_perf = ioread32(dom->fc_info->limit_get_addr + 4);
> +		return 0;
> +	}
> +
> +	return scmi_perf_mb_limits_get(handle, domain, max_perf, min_perf); }
> +
> +static int scmi_perf_mb_level_set(const struct scmi_handle *handle, u32
> +domain,
>  				  u32 level, bool poll)
>  {
>  	int ret;
> @@ -365,7 +432,22 @@ static int scmi_perf_level_set(const struct
> scmi_handle *handle, u32 domain,
>  	return ret;
>  }
> 
> -static int scmi_perf_level_get(const struct scmi_handle *handle, u32 domain,
> +static int scmi_perf_level_set(const struct scmi_handle *handle, u32
> domain,
> +			       u32 level, bool poll)
> +{
> +	struct scmi_perf_info *pi = handle->perf_priv;
> +	struct perf_dom_info *dom = pi->dom_info + domain;
> +
> +	if (dom->fc_info && dom->fc_info->level_set_addr) {
> +		iowrite32(level, dom->fc_info->level_set_addr);
> +		scmi_perf_fc_ring_db(dom->fc_info->level_set_db);
> +		return 0;
> +	}
> +
> +	return scmi_perf_mb_level_set(handle, domain, level, poll); }
> +
> +static int scmi_perf_mb_level_get(const struct scmi_handle *handle, u32
> +domain,
>  				  u32 *level, bool poll)
>  {
>  	int ret;
> @@ -387,6 +469,20 @@ static int scmi_perf_level_get(const struct
> scmi_handle *handle, u32 domain,
>  	return ret;
>  }
> 
> +static int scmi_perf_level_get(const struct scmi_handle *handle, u32
> domain,
> +			       u32 *level, bool poll)
> +{
> +	struct scmi_perf_info *pi = handle->perf_priv;
> +	struct perf_dom_info *dom = pi->dom_info + domain;
> +
> +	if (dom->fc_info && dom->fc_info->level_get_addr) {
> +		*level = ioread32(dom->fc_info->level_get_addr);
> +		return 0;
> +	}
> +
> +	return scmi_perf_mb_level_get(handle, domain, level, poll); }
> +
>  static bool scmi_perf_fc_size_is_valid(u32 msg, u32 size)  {
>  	if ((msg == PERF_LEVEL_GET || msg == PERF_LEVEL_SET) && size == 4)

Reviewed-by: Peng Fan <peng.fan@xxxxxxx>

> --
> 2.17.1