Hi Shawn,
On 05/16/2017 03:28 PM, Shawn Lin wrote:
> Currently we unconditionally do tuning for each degree, which
> costs 900ms for each boot and resume.
>
> May someone argue that this is a question of accuracy VS time. But I
> would say it's a trick of how we need to do decision for our boards.
> If we don't care the time we spend at all, we could definitely do tuning
> for each degree. But when we need to improve the user experience, for
> instance, speed up resuming from S3, we should also have the right to
> do that. This patch add parsing "rockchip,desired-num-phases", for folks
> to specify the number of doing tuning. If not specified, 360 will be used
> as before.
>
> Signed-off-by: Shawn Lin <shawn.lin@xxxxxxxxxxxxxx>
Will pick this patch with [PATCH 1/2] after getting acked tags from DT guys.
Best Regards,
Jaehoon Chung
>
> ---
>
> Changes in v2:
> - rename property to rockchip,desired-num-phases
>
> drivers/mmc/host/dw_mmc-rockchip.c | 48 ++++++++++++++++++++++++--------------
> 1 file changed, 30 insertions(+), 18 deletions(-)
>
> diff --git a/drivers/mmc/host/dw_mmc-rockchip.c b/drivers/mmc/host/dw_mmc-rockchip.c
> index 372fb6e..a3f1c2b 100644
> --- a/drivers/mmc/host/dw_mmc-rockchip.c
> +++ b/drivers/mmc/host/dw_mmc-rockchip.c
> @@ -25,6 +25,7 @@ struct dw_mci_rockchip_priv_data {
> struct clk *drv_clk;
> struct clk *sample_clk;
> int default_sample_phase;
> + int num_phases;
> };
>
> static void dw_mci_rk3288_set_ios(struct dw_mci *host, struct mmc_ios *ios)
> @@ -133,8 +134,8 @@ static void dw_mci_rk3288_set_ios(struct dw_mci *host, struct mmc_ios *ios)
> }
> }
>
> -#define NUM_PHASES 360
> -#define TUNING_ITERATION_TO_PHASE(i) (DIV_ROUND_UP((i) * 360, NUM_PHASES))
> +#define TUNING_ITERATION_TO_PHASE(i, num_phases) \
> + (DIV_ROUND_UP((i) * 360, num_phases))
>
> static int dw_mci_rk3288_execute_tuning(struct dw_mci_slot *slot, u32 opcode)
> {
> @@ -159,13 +160,15 @@ static int dw_mci_rk3288_execute_tuning(struct dw_mci_slot *slot, u32 opcode)
> return -EIO;
> }
>
> - ranges = kmalloc_array(NUM_PHASES / 2 + 1, sizeof(*ranges), GFP_KERNEL);
> + ranges = kmalloc_array(priv->num_phases / 2 + 1,
> + sizeof(*ranges), GFP_KERNEL);
> if (!ranges)
> return -ENOMEM;
>
> /* Try each phase and extract good ranges */
> - for (i = 0; i < NUM_PHASES; ) {
> - clk_set_phase(priv->sample_clk, TUNING_ITERATION_TO_PHASE(i));
> + for (i = 0; i < priv->num_phases; ) {
> + clk_set_phase(priv->sample_clk,
> + TUNING_ITERATION_TO_PHASE(i, priv->num_phases));
>
> v = !mmc_send_tuning(mmc, opcode, NULL);
>
> @@ -179,7 +182,7 @@ static int dw_mci_rk3288_execute_tuning(struct dw_mci_slot *slot, u32 opcode)
> if (v) {
> ranges[range_count-1].end = i;
> i++;
> - } else if (i == NUM_PHASES - 1) {
> + } else if (i == priv->num_phases - 1) {
> /* No extra skipping rules if we're at the end */
> i++;
> } else {
> @@ -188,11 +191,11 @@ static int dw_mci_rk3288_execute_tuning(struct dw_mci_slot *slot, u32 opcode)
> * one since testing bad phases is slow. Skip
> * 20 degrees.
> */
> - i += DIV_ROUND_UP(20 * NUM_PHASES, 360);
> + i += DIV_ROUND_UP(20 * priv->num_phases, 360);
>
> /* Always test the last one */
> - if (i >= NUM_PHASES)
> - i = NUM_PHASES - 1;
> + if (i >= priv->num_phases)
> + i = priv->num_phases - 1;
> }
>
> prev_v = v;
> @@ -210,7 +213,7 @@ static int dw_mci_rk3288_execute_tuning(struct dw_mci_slot *slot, u32 opcode)
> range_count--;
> }
>
> - if (ranges[0].start == 0 && ranges[0].end == NUM_PHASES - 1) {
> + if (ranges[0].start == 0 && ranges[0].end == priv->num_phases - 1) {
> clk_set_phase(priv->sample_clk, priv->default_sample_phase);
> dev_info(host->dev, "All phases work, using default phase %d.",
> priv->default_sample_phase);
> @@ -222,7 +225,7 @@ static int dw_mci_rk3288_execute_tuning(struct dw_mci_slot *slot, u32 opcode)
> int len = (ranges[i].end - ranges[i].start + 1);
>
> if (len < 0)
> - len += NUM_PHASES;
> + len += priv->num_phases;
>
> if (longest_range_len < len) {
> longest_range_len = len;
> @@ -230,25 +233,30 @@ static int dw_mci_rk3288_execute_tuning(struct dw_mci_slot *slot, u32 opcode)
> }
>
> dev_dbg(host->dev, "Good phase range %d-%d (%d len)\n",
> - TUNING_ITERATION_TO_PHASE(ranges[i].start),
> - TUNING_ITERATION_TO_PHASE(ranges[i].end),
> + TUNING_ITERATION_TO_PHASE(ranges[i].start,
> + priv->num_phases),
> + TUNING_ITERATION_TO_PHASE(ranges[i].end,
> + priv->num_phases),
> len
> );
> }
>
> dev_dbg(host->dev, "Best phase range %d-%d (%d len)\n",
> - TUNING_ITERATION_TO_PHASE(ranges[longest_range].start),
> - TUNING_ITERATION_TO_PHASE(ranges[longest_range].end),
> + TUNING_ITERATION_TO_PHASE(ranges[longest_range].start,
> + priv->num_phases),
> + TUNING_ITERATION_TO_PHASE(ranges[longest_range].end,
> + priv->num_phases),
> longest_range_len
> );
>
> middle_phase = ranges[longest_range].start + longest_range_len / 2;
> - middle_phase %= NUM_PHASES;
> + middle_phase %= priv->num_phases;
> dev_info(host->dev, "Successfully tuned phase to %d\n",
> - TUNING_ITERATION_TO_PHASE(middle_phase));
> + TUNING_ITERATION_TO_PHASE(middle_phase, priv->num_phases));
>
> clk_set_phase(priv->sample_clk,
> - TUNING_ITERATION_TO_PHASE(middle_phase));
> + TUNING_ITERATION_TO_PHASE(middle_phase,
> + priv->num_phases));
>
> free:
> kfree(ranges);
> @@ -264,6 +272,10 @@ static int dw_mci_rk3288_parse_dt(struct dw_mci *host)
> if (!priv)
> return -ENOMEM;
>
> + if (of_property_read_u32(np, "rockchip,desired-num-phases",
> + &priv->num_phases))
> + priv->num_phases = 360;
> +
> if (of_property_read_u32(np, "rockchip,default-sample-phase",
> &priv->default_sample_phase))
> priv->default_sample_phase = 0;
>
--
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