[PATCH v2] clk: sunxi: predivider handling for factors clock
Vishnu Patekar
vishnupatekar0510 at gmail.com
Tue Apr 26 10:55:48 PDT 2016
Hello Wens,
On Mon, Apr 25, 2016 at 10:51 PM, Chen-Yu Tsai <wens at csie.org> wrote:
> Hi,
>
> On Wed, Apr 20, 2016 at 12:47 AM, Vishnu Patekar
> <vishnupatekar0510 at gmail.com> wrote:
>> For A31 ahb1 and a83t ahb1 clocks have predivider for certain parent.
>> To handle this, this patch adds predivider table with parent index,
>> prediv shift and width, parents with predivider will have nonzero width.
>>
>> Rate adjustment is moved from clock specific recalc function to generic
>> factors recalc. Also, adds prediv table for a31.
>>
>> Signed-off-by: Vishnu Patekar <vishnupatekar0510 at gmail.com>
>> ---
>> drivers/clk/sunxi/clk-factors.c | 31 +++++++++++++++----------------
>> drivers/clk/sunxi/clk-factors.h | 10 +++++++++-
>> drivers/clk/sunxi/clk-sunxi.c | 31 +++++++++----------------------
>> 3 files changed, 33 insertions(+), 39 deletions(-)
>>
>> diff --git a/drivers/clk/sunxi/clk-factors.c b/drivers/clk/sunxi/clk-factors.c
>> index ddefe96..8f3b637 100644
>> --- a/drivers/clk/sunxi/clk-factors.c
>> +++ b/drivers/clk/sunxi/clk-factors.c
>> @@ -45,10 +45,12 @@ static unsigned long clk_factors_recalc_rate(struct clk_hw *hw,
>> unsigned long parent_rate)
>> {
>> u8 n = 1, k = 0, p = 0, m = 0;
>> + u8 par_index = 0;
>> u32 reg;
>> unsigned long rate;
>> struct clk_factors *factors = to_clk_factors(hw);
>> const struct clk_factors_config *config = factors->config;
>> + const struct clk_factors_prediv *prediv = factors->prediv_config;
>>
>> /* Fetch the register value */
>> reg = readl(factors->reg);
>> @@ -63,24 +65,16 @@ static unsigned long clk_factors_recalc_rate(struct clk_hw *hw,
>> if (config->pwidth != SUNXI_FACTORS_NOT_APPLICABLE)
>> p = FACTOR_GET(config->pshift, config->pwidth, reg);
>>
>> - if (factors->recalc) {
>> - struct factors_request factors_req = {
>> - .parent_rate = parent_rate,
>> - .n = n,
>> - .k = k,
>> - .m = m,
>> - .p = p,
>> - };
>> -
>> + if (prediv) {
>> /* get mux details from mux clk structure */
>> if (factors->mux)
>> - factors_req.parent_index =
>> - (reg >> factors->mux->shift) &
>> - factors->mux->mask;
>> -
>> - factors->recalc(&factors_req);
>> + par_index = (reg >> factors->mux->shift) &
>> + factors->mux->mask;
>>
>> - return factors_req.rate;
>> + if (prediv[par_index].width != SUNXI_FACTORS_NOT_APPLICABLE) {
>> + m = FACTOR_GET(prediv[par_index].shift,
>> + prediv[par_index].width, reg);
>> + }
>> }
>>
>> /* Calculate the rate */
>> @@ -102,8 +96,12 @@ static int clk_factors_determine_rate(struct clk_hw *hw,
>> for (i = 0; i < num_parents; i++) {
>> struct factors_request factors_req = {
>> .rate = req->rate,
>> - .parent_index = i,
>> };
>> +
>> + if (factors->prediv_config)
>> + factors_req.prediv_width =
>> + factors->prediv_config[i].width;
>> +
>> parent = clk_hw_get_parent_by_index(hw, i);
>> if (!parent)
>> continue;
>> @@ -211,6 +209,7 @@ struct clk *sunxi_factors_register(struct device_node *node,
>> /* set up factors properties */
>> factors->reg = reg;
>> factors->config = data->table;
>> + factors->prediv_config = data->prediv_table;
>> factors->get_factors = data->getter;
>> factors->recalc = data->recalc;
>> factors->lock = lock;
>> diff --git a/drivers/clk/sunxi/clk-factors.h b/drivers/clk/sunxi/clk-factors.h
>> index 1e63c5b..b1b7745 100644
>> --- a/drivers/clk/sunxi/clk-factors.h
>> +++ b/drivers/clk/sunxi/clk-factors.h
>> @@ -18,10 +18,16 @@ struct clk_factors_config {
>> u8 n_start;
>> };
>>
>> +struct clk_factors_prediv {
>> + u8 parent_index;
>> + u8 shift;
>> + u8 width;
>> +};
>> +
>> struct factors_request {
>> unsigned long rate;
>> unsigned long parent_rate;
>> - u8 parent_index;
>> + u8 prediv_width;
>> u8 n;
>> u8 k;
>> u8 m;
>> @@ -33,6 +39,7 @@ struct factors_data {
>> int mux;
>> int muxmask;
>> const struct clk_factors_config *table;
>> + const struct clk_factors_prediv *prediv_table;
>> void (*getter)(struct factors_request *req);
>> void (*recalc)(struct factors_request *req);
>
> You removed usage of this callback. Please remove it from the data structures
> as well, so no one assumes it's still applicable.
Okie, I'll remove it.
>
>> const char *name;
>> @@ -42,6 +49,7 @@ struct clk_factors {
>> struct clk_hw hw;
>> void __iomem *reg;
>> const struct clk_factors_config *config;
>> + const struct clk_factors_prediv *prediv_config;
>> void (*get_factors)(struct factors_request *req);
>> void (*recalc)(struct factors_request *req);
>> spinlock_t *lock;
>> diff --git a/drivers/clk/sunxi/clk-sunxi.c b/drivers/clk/sunxi/clk-sunxi.c
>> index 91de0a0..5a5f26b 100644
>> --- a/drivers/clk/sunxi/clk-sunxi.c
>> +++ b/drivers/clk/sunxi/clk-sunxi.c
>> @@ -282,8 +282,6 @@ static void sun5i_a13_get_ahb_factors(struct factors_request *req)
>> req->p = div;
>> }
>>
>> -#define SUN6I_AHB1_PARENT_PLL6 3
>> -
>> /**
>> * sun6i_a31_get_ahb_factors() - calculates m, p factors for AHB
>> * AHB rate is calculated as follows
>> @@ -307,7 +305,7 @@ static void sun6i_get_ahb1_factors(struct factors_request *req)
>> div = DIV_ROUND_UP(req->parent_rate, req->rate);
>>
>> /* calculate pre-divider if parent is pll6 */
>> - if (req->parent_index == SUN6I_AHB1_PARENT_PLL6) {
>> + if (req->prediv_width) {
>> if (div < 4)
>> calcp = 0;
>> else if (div / 2 < 4)
>> @@ -329,22 +327,6 @@ static void sun6i_get_ahb1_factors(struct factors_request *req)
>> }
>>
>> /**
>> - * sun6i_ahb1_recalc() - calculates AHB clock rate from m, p factors and
>> - * parent index
>> - */
>> -static void sun6i_ahb1_recalc(struct factors_request *req)
>> -{
>> - req->rate = req->parent_rate;
>> -
>> - /* apply pre-divider first if parent is pll6 */
>> - if (req->parent_index == SUN6I_AHB1_PARENT_PLL6)
>> - req->rate /= req->m + 1;
>> -
>> - /* clk divider */
>> - req->rate >>= req->p;
>> -}
>> -
>> -/**
>> * sun4i_get_apb1_factors() - calculates m, p factors for APB1
>> * APB1 rate is calculated as follows
>> * rate = (parent_rate >> p) / (m + 1);
>> @@ -474,12 +456,17 @@ static const struct clk_factors_config sun5i_a13_ahb_config = {
>> };
>>
>> static const struct clk_factors_config sun6i_ahb1_config = {
>> - .mshift = 6,
>> - .mwidth = 2,
>> .pshift = 4,
>> .pwidth = 2,
>> };
>>
>> +static const struct clk_factors_prediv sun6i_ahb1_prediv[] = {
>> + {.parent_index = 0, .shift = 0, .width = 0 }, /* LOSC */
>> + {.parent_index = 1, .shift = 0, .width = 0 }, /* OSC24MHz */
>> + {.parent_index = 2, .shift = 0, .width = 0 }, /* AXI */
>> + {.parent_index = 3, .shift = 6, .width = 2 } /* PLL6/Pre_div */
>
> ^ a space here would be nice. ^
> spaces around here too.
Okie.
>
>> +};
>> +
>> static const struct clk_factors_config sun4i_apb1_config = {
>> .mshift = 0,
>> .mwidth = 5,
>> @@ -551,8 +538,8 @@ static const struct factors_data sun6i_ahb1_data __initconst = {
>> .mux = 12,
>> .muxmask = BIT(1) | BIT(0),
>> .table = &sun6i_ahb1_config,
>> + .prediv_table = sun6i_ahb1_prediv,
>> .getter = sun6i_get_ahb1_factors,
>> - .recalc = sun6i_ahb1_recalc,
>> };
>>
>> static const struct factors_data sun4i_apb1_data __initconst = {
>> --
>> 1.9.1
>>
>
> The rest looks good.
Thanks for the review.
>
> Regards
> ChenYu
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