Hi Geert
Thank you for your review.
> > +static const struct sh_mmcif_parent_clk mmcif_gen2_parent_clk = {
> > + .max = 97500000,
> > + .min = 12187500,
> > + .clkdiv_map = 0x3ff,
>
> Shouldn't this come from private data in the CPG clock driver, which supplies
> the parent clock? Then the mmcif driver will be independent from the parent
> clock.
As Laurent mentioned in other feedback, parent clock (= CFG::MMCxCKCR)
is div6, and it can set 1/1 - 1/64 (= 780000000 - 12187500)
But, MMC can use 1/8 - 1/64 (= 97500000 - 12187500), we don't know this limit
came from. we thought that having limit on DIV6 is not good idea.
> > + /* FIXME */
> > + if (pclk->max != pclk->min * (pclk->max / pclk->min)) {
> > + dev_err(&host->pd->dev, "not assumed parent clk\n");
> > + return;
> > + }
>
> Why?
This time, max/min = 97500000/12187500 = 8.
But, we don't know the future.
It will be non-assumed result if it was below or similar
max = 91406250
min = 12187500 (max = min * 15/2)
> > + parent_freq = 0;
> > + clkdiv = 0;
> > + diff_min = ~0;
> > + for (i = pclk->max / pclk->min; i > 0; i--) {
> > + for (j = fls(pclk->clkdiv_map); j >= 0; j--) {
> > + if (!((1 << j) & pclk->clkdiv_map))
> > + continue;
> > +
> > + myclk = ((pclk->min * i) / (1 << (j + 1)));
> > + diff = (myclk > clk) ? myclk - clk : clk -
> > myclk;
> > +
> > + if (diff <= diff_min) {
> > + parent_freq = pclk->min * i;
> > + clkdiv = j;
> > + diff_min = diff;
> > + }
> > + }
> > + }
>
> Shouldn't the above be handled by the CPG clock driver, through a clk API?
I don't think so.
it calculates best of parent clock (= from CPG) and divider (= from MMC)
Why CPG driver need to care about MMC's divider ??
> > + dev_dbg(&host->pd->dev, "clk %d/%d (%d, %x)\n",
>
> "%u" (all four)
(snip)
> > + clk_set_rate(host->hclk, parent_freq);
>
> Note that the last parameter of clk_set_rate() is "unsigned long", while
> parent_freq is "unsigned int".
(snip)
> > + host->clk = clk_get_rate(host->hclk);
>
> clk_get_rate() returns "unsigned long", while "host->clk" is "unsigned int".
(snip)
> > + dev_dbg(&host->pd->dev, "parent clk %d/%d, %d/%d\n",
>
> "%u" (all four)
Thanks !
I will fixup these in v2
Best regards
---
Kuninori Morimoto
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