Re: [PATCH v3 2/4] clk: at91: sckc: add support to specify registers bit offsets

Claudiu.Beznea
2019-05-16T08:10:34Z

On 11.05.2019 00:32, Alexandre Belloni wrote:
> On 10/05/2019 11:23:31+0000, Claudiu.Beznea@microchip.com wrote:
>> From: Claudiu Beznea <claudiu.beznea@microchip.com>
>>
>> Different IPs uses different bit offsets in registers for the same
>> functionality, thus adapt the driver to support this.
>>
>> Signed-off-by: Claudiu Beznea <claudiu.beznea@microchip.com>
>> ---
>> drivers/clk/at91/sckc.c | 100 ++++++++++++++++++++++++++++++++----------------
>> 1 file changed, 67 insertions(+), 33 deletions(-)
>>
>> diff --git a/drivers/clk/at91/sckc.c b/drivers/clk/at91/sckc.c
>> index 6c55a7a86f79..2a4ac548de80 100644
>> --- a/drivers/clk/at91/sckc.c
>> +++ b/drivers/clk/at91/sckc.c
>> @@ -22,15 +22,23 @@
>> #define SLOWCK_SW_TIME_USEC ((SLOWCK_SW_CYCLES * USEC_PER_SEC) / \
>> SLOW_CLOCK_FREQ)
>>
>> -#define AT91_SCKC_CR 0x00
>> -#define AT91_SCKC_RCEN (1 << 0)
>> -#define AT91_SCKC_OSC32EN (1 << 1)
>> -#define AT91_SCKC_OSC32BYP (1 << 2)
>> -#define AT91_SCKC_OSCSEL (1 << 3)
>> +#define AT91_SCKC_CR 0x00
>> +#define AT91_SCKC_RCEN(off) ((off)->cr_rcen)
>> +#define AT91_SCKC_OSC32EN(off) ((off)->cr_osc32en)
>> +#define AT91_SCKC_OSC32BYP(off) ((off)->cr_osc32byp)
>> +#define AT91_SCKC_OSCSEL(off) ((off)->cr_oscsel)
>> +
>> +struct clk_slow_bits {
>> + u32 cr_rcen;
>
> This bit is only used on sam9x5 so I wouldn't bother having it in the
> structure, especially since its use will always be quite separate from
> the other ones as it is controlling a separate clock.
>
>> + u32 cr_osc32en;
>> + u32 cr_osc32byp;
>> + u32 cr_oscsel;
>> +};
>>
>> struct clk_slow_osc {
>> struct clk_hw hw;
>> void __iomem *sckcr;
>> + const struct clk_slow_bits *bits;
>> unsigned long startup_usec;
>> };
>>
>> @@ -39,6 +47,7 @@ struct clk_slow_osc {
>> struct clk_sama5d4_slow_osc {
>> struct clk_hw hw;
>> void __iomem *sckcr;
>> + const struct clk_slow_bits *bits;
>> unsigned long startup_usec;
>> bool prepared;
>> };
>> @@ -48,6 +57,7 @@ struct clk_sama5d4_slow_osc {
>> struct clk_slow_rc_osc {
>> struct clk_hw hw;
>> void __iomem *sckcr;
>> + const struct clk_slow_bits *bits;
>> unsigned long frequency;
>> unsigned long accuracy;
>> unsigned long startup_usec;
>> @@ -58,6 +68,7 @@ struct clk_slow_rc_osc {
>> struct clk_sam9x5_slow {
>> struct clk_hw hw;
>> void __iomem *sckcr;
>> + const struct clk_slow_bits *bits;
>> u8 parent;
>> };
>>
>> @@ -69,10 +80,11 @@ static int clk_slow_osc_prepare(struct clk_hw *hw)
>> void __iomem *sckcr = osc->sckcr;
>> u32 tmp = readl(sckcr);
>>
>> - if (tmp & (AT91_SCKC_OSC32BYP | AT91_SCKC_OSC32EN))
>> + if (tmp & (AT91_SCKC_OSC32BYP(osc->bits) |
>> + AT91_SCKC_OSC32EN(osc->bits)))
>
> I still find that:
>
> if (tmp & (osc->bits->cr_osc32byp | osc->bits->cr_osc32en))
>
> would be shorter and easier to read and still fits on one line.

Agree, but I thought to use the same interface everywhere. Anyway, tell me
if you want to resend with these changes.

>