[PATCH v2 2/2] mmc: dw_mmc-rockchip: parse rockchip,desired-num-phases from DT
Shawn Lin
shawn.lin at rock-chips.com
Wed Jun 28 18:38:42 PDT 2017
Hi Jaehoon,
On 2017/5/18 10:20, Jaehoon Chung wrote:
> 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 at rock-chips.com>
>
> Will pick this patch with [PATCH 1/2] after getting acked tags from DT guys.
>
patch 1 was acked by Rob, so I assume these two are material for 4.13?
> 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;
>>
>
>
> _______________________________________________
> Linux-rockchip mailing list
> Linux-rockchip at lists.infradead.org
> http://lists.infradead.org/mailman/listinfo/linux-rockchip
>
>
>
More information about the Linux-rockchip
mailing list