diff options
| author | Keerthy | 2016-12-02 14:35:43 +0530 |
|---|---|---|
| committer | Stephen Boyd | 2017-01-26 16:03:04 -0800 |
| commit | ced3068344ec9730eb160b462154e5fc53f6c2c5 (patch) | |
| tree | b39b588743555c21d5588baa9f4a5b63e7083515 /drivers/clk | |
| parent | 843be1e7fb30f6309aa9389344b16dca57e6d4e2 (diff) | |
clk: ti: divider: Add the table parsing to get the best divider value
Currently the divider selection logic blindly divides the parent_rate
by the clk rate and gives the divider value for the divider clocks
which do not have the CLK_SET_RATE_PARENT flag set. Add the clk divider
table parsing to get the closest divider available in the table
provided via Device tree.
The code is pretty much taken from: drivers/clk/clk-divider.c.
and used here to fix up the best divider selection logic.
Signed-off-by: Keerthy <j-keerthy@ti.com>
Reported-by: Richard Woodruff <r-woodruff2@ti.com>
Acked-by: Tero Kristo <t-kristo@ti.com>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Diffstat (limited to 'drivers/clk')
| -rw-r--r-- | drivers/clk/ti/divider.c | 31 |
1 files changed, 30 insertions, 1 deletions
diff --git a/drivers/clk/ti/divider.c b/drivers/clk/ti/divider.c index b4e5de16e561..6bb87784a0d6 100644 --- a/drivers/clk/ti/divider.c +++ b/drivers/clk/ti/divider.c @@ -140,6 +140,35 @@ static bool _is_valid_div(struct clk_divider *divider, unsigned int div) return true; } +static int _div_round_up(const struct clk_div_table *table, + unsigned long parent_rate, unsigned long rate) +{ + const struct clk_div_table *clkt; + int up = INT_MAX; + int div = DIV_ROUND_UP_ULL((u64)parent_rate, rate); + + for (clkt = table; clkt->div; clkt++) { + if (clkt->div == div) + return clkt->div; + else if (clkt->div < div) + continue; + + if ((clkt->div - div) < (up - div)) + up = clkt->div; + } + + return up; +} + +static int _div_round(const struct clk_div_table *table, + unsigned long parent_rate, unsigned long rate) +{ + if (!table) + return DIV_ROUND_UP(parent_rate, rate); + + return _div_round_up(table, parent_rate, rate); +} + static int ti_clk_divider_bestdiv(struct clk_hw *hw, unsigned long rate, unsigned long *best_parent_rate) { @@ -155,7 +184,7 @@ static int ti_clk_divider_bestdiv(struct clk_hw *hw, unsigned long rate, if (!(clk_hw_get_flags(hw) & CLK_SET_RATE_PARENT)) { parent_rate = *best_parent_rate; - bestdiv = DIV_ROUND_UP(parent_rate, rate); + bestdiv = _div_round(divider->table, parent_rate, rate); bestdiv = bestdiv == 0 ? 1 : bestdiv; bestdiv = bestdiv > maxdiv ? maxdiv : bestdiv; return bestdiv; |