[PATCH v2 02/36] soc: fsl: cpm1: qmc: Enable TRNSYNC only when needed

[Christophe Leroy]

Le 08/08/2024 à 09:10, Herve Codina a écrit :
> The TRNSYNC feature is enabled whatever the number of time-slots used.
> The feature is needed only when more than one time-slot is used.
> 
> Improve the driver enabling TRNSYNC only when it is needed.
> 
> Signed-off-by: Herve Codina <herve.codina at bootlin.com>

Reviewed-by: Christophe Leroy <christophe.leroy at csgroup.eu>


> ---
>   drivers/soc/fsl/qe/qmc.c | 12 +++++++++++-
>   1 file changed, 11 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/soc/fsl/qe/qmc.c b/drivers/soc/fsl/qe/qmc.c
> index bacabf731dcb..916395745850 100644
> --- a/drivers/soc/fsl/qe/qmc.c
> +++ b/drivers/soc/fsl/qe/qmc.c
> @@ -889,6 +889,7 @@ EXPORT_SYMBOL(qmc_chan_stop);
>   static int qmc_setup_chan_trnsync(struct qmc *qmc, struct qmc_chan *chan)
>   {
>   	struct tsa_serial_info info;
> +	unsigned int w_rx, w_tx;
>   	u16 first_rx, last_tx;
>   	u16 trnsync;
>   	int ret;
> @@ -898,6 +899,14 @@ static int qmc_setup_chan_trnsync(struct qmc *qmc, struct qmc_chan *chan)
>   	if (ret)
>   		return ret;
>   
> +	w_rx = hweight64(chan->rx_ts_mask);
> +	w_tx = hweight64(chan->tx_ts_mask);
> +	if (w_rx <= 1 && w_tx <= 1) {
> +		dev_dbg(qmc->dev, "only one or zero ts -> disable trnsync\n");
> +		qmc_clrbits16(chan->s_param + QMC_SPE_CHAMR, QMC_SPE_CHAMR_TRANSP_SYNC);
> +		return 0;
> +	}
> +
>   	/* Find the first Rx TS allocated to the channel */
>   	first_rx = chan->rx_ts_mask ? __ffs64(chan->rx_ts_mask) + 1 : 0;
>   
> @@ -911,6 +920,7 @@ static int qmc_setup_chan_trnsync(struct qmc *qmc, struct qmc_chan *chan)
>   		trnsync |= QMC_SPE_TRNSYNC_TX((last_tx % info.nb_tx_ts) * 2);
>   
>   	qmc_write16(chan->s_param + QMC_SPE_TRNSYNC, trnsync);
> +	qmc_setbits16(chan->s_param + QMC_SPE_CHAMR, QMC_SPE_CHAMR_TRANSP_SYNC);
>   
>   	dev_dbg(qmc->dev, "chan %u: trnsync=0x%04x, rx %u/%u 0x%llx, tx %u/%u 0x%llx\n",
>   		chan->id, trnsync,
> @@ -1378,7 +1388,7 @@ static int qmc_setup_chan(struct qmc *qmc, struct qmc_chan *chan)
>   	if (chan->mode == QMC_TRANSPARENT) {
>   		qmc_write32(chan->s_param + QMC_SPE_ZDSTATE, 0x18000080);
>   		qmc_write16(chan->s_param + QMC_SPE_TMRBLR, 60);
> -		val = QMC_SPE_CHAMR_MODE_TRANSP | QMC_SPE_CHAMR_TRANSP_SYNC;
> +		val = QMC_SPE_CHAMR_MODE_TRANSP;
>   		if (chan->is_reverse_data)
>   			val |= QMC_SPE_CHAMR_TRANSP_RD;
>   		qmc_write16(chan->s_param + QMC_SPE_CHAMR, val);