Re: [PATCH v4 2/4] clk: at91: sckc: add support to specify registers bit offsets

From: Alexandre Belloni
Date: Tue May 21 2019 - 06:51:43 EST


On 21/05/2019 10:11:26+0000, Claudiu.Beznea@xxxxxxxxxxxxx wrote:
> From: Claudiu Beznea <claudiu.beznea@xxxxxxxxxxxxx>
>
> 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@xxxxxxxxxxxxx>
Acked-by: Alexandre Belloni <alexandre.belloni@xxxxxxxxxxx>

> ---
> drivers/clk/at91/sckc.c | 93 ++++++++++++++++++++++++++++++++-----------------
> 1 file changed, 61 insertions(+), 32 deletions(-)
>
> diff --git a/drivers/clk/at91/sckc.c b/drivers/clk/at91/sckc.c
> index 6c55a7a86f79..ab18b1da269f 100644
> --- a/drivers/clk/at91/sckc.c
> +++ b/drivers/clk/at91/sckc.c
> @@ -23,14 +23,18 @@
> 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)
> +
> +struct clk_slow_bits {
> + u32 cr_rcen;
> + 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 +43,7 @@ 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 +53,7 @@ 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 +64,7 @@ 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 +76,10 @@ 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 & (osc->bits->cr_osc32byp | osc->bits->cr_osc32en))
> return 0;
>
> - writel(tmp | AT91_SCKC_OSC32EN, sckcr);
> + writel(tmp | osc->bits->cr_osc32en, sckcr);
>
> usleep_range(osc->startup_usec, osc->startup_usec + 1);
>
> @@ -85,10 +92,10 @@ static void clk_slow_osc_unprepare(struct clk_hw *hw)
> void __iomem *sckcr = osc->sckcr;
> u32 tmp = readl(sckcr);
>
> - if (tmp & AT91_SCKC_OSC32BYP)
> + if (tmp & osc->bits->cr_osc32byp)
> return;
>
> - writel(tmp & ~AT91_SCKC_OSC32EN, sckcr);
> + writel(tmp & ~osc->bits->cr_osc32en, sckcr);
> }
>
> static int clk_slow_osc_is_prepared(struct clk_hw *hw)
> @@ -97,10 +104,10 @@ static int clk_slow_osc_is_prepared(struct clk_hw *hw)
> void __iomem *sckcr = osc->sckcr;
> u32 tmp = readl(sckcr);
>
> - if (tmp & AT91_SCKC_OSC32BYP)
> + if (tmp & osc->bits->cr_osc32byp)
> return 1;
>
> - return !!(tmp & AT91_SCKC_OSC32EN);
> + return !!(tmp & osc->bits->cr_osc32en);
> }
>
> static const struct clk_ops slow_osc_ops = {
> @@ -114,7 +121,8 @@ at91_clk_register_slow_osc(void __iomem *sckcr,
> const char *name,
> const char *parent_name,
> unsigned long startup,
> - bool bypass)
> + bool bypass,
> + const struct clk_slow_bits *bits)
> {
> struct clk_slow_osc *osc;
> struct clk_hw *hw;
> @@ -137,10 +145,11 @@ at91_clk_register_slow_osc(void __iomem *sckcr,
> osc->hw.init = &init;
> osc->sckcr = sckcr;
> osc->startup_usec = startup;
> + osc->bits = bits;
>
> if (bypass)
> - writel((readl(sckcr) & ~AT91_SCKC_OSC32EN) | AT91_SCKC_OSC32BYP,
> - sckcr);
> + writel((readl(sckcr) & ~osc->bits->cr_osc32en) |
> + osc->bits->cr_osc32byp, sckcr);
>
> hw = &osc->hw;
> ret = clk_hw_register(NULL, &osc->hw);
> @@ -173,7 +182,7 @@ static int clk_slow_rc_osc_prepare(struct clk_hw *hw)
> struct clk_slow_rc_osc *osc = to_clk_slow_rc_osc(hw);
> void __iomem *sckcr = osc->sckcr;
>
> - writel(readl(sckcr) | AT91_SCKC_RCEN, sckcr);
> + writel(readl(sckcr) | osc->bits->cr_rcen, sckcr);
>
> usleep_range(osc->startup_usec, osc->startup_usec + 1);
>
> @@ -185,14 +194,14 @@ static void clk_slow_rc_osc_unprepare(struct clk_hw *hw)
> struct clk_slow_rc_osc *osc = to_clk_slow_rc_osc(hw);
> void __iomem *sckcr = osc->sckcr;
>
> - writel(readl(sckcr) & ~AT91_SCKC_RCEN, sckcr);
> + writel(readl(sckcr) & ~osc->bits->cr_rcen, sckcr);
> }
>
> static int clk_slow_rc_osc_is_prepared(struct clk_hw *hw)
> {
> struct clk_slow_rc_osc *osc = to_clk_slow_rc_osc(hw);
>
> - return !!(readl(osc->sckcr) & AT91_SCKC_RCEN);
> + return !!(readl(osc->sckcr) & osc->bits->cr_rcen);
> }
>
> static const struct clk_ops slow_rc_osc_ops = {
> @@ -208,7 +217,8 @@ at91_clk_register_slow_rc_osc(void __iomem *sckcr,
> const char *name,
> unsigned long frequency,
> unsigned long accuracy,
> - unsigned long startup)
> + unsigned long startup,
> + const struct clk_slow_bits *bits)
> {
> struct clk_slow_rc_osc *osc;
> struct clk_hw *hw;
> @@ -230,6 +240,7 @@ at91_clk_register_slow_rc_osc(void __iomem *sckcr,
>
> osc->hw.init = &init;
> osc->sckcr = sckcr;
> + osc->bits = bits;
> osc->frequency = frequency;
> osc->accuracy = accuracy;
> osc->startup_usec = startup;
> @@ -255,14 +266,14 @@ static int clk_sam9x5_slow_set_parent(struct clk_hw *hw, u8 index)
>
> tmp = readl(sckcr);
>
> - if ((!index && !(tmp & AT91_SCKC_OSCSEL)) ||
> - (index && (tmp & AT91_SCKC_OSCSEL)))
> + if ((!index && !(tmp & slowck->bits->cr_oscsel)) ||
> + (index && (tmp & slowck->bits->cr_oscsel)))
> return 0;
>
> if (index)
> - tmp |= AT91_SCKC_OSCSEL;
> + tmp |= slowck->bits->cr_oscsel;
> else
> - tmp &= ~AT91_SCKC_OSCSEL;
> + tmp &= ~slowck->bits->cr_oscsel;
>
> writel(tmp, sckcr);
>
> @@ -275,7 +286,7 @@ static u8 clk_sam9x5_slow_get_parent(struct clk_hw *hw)
> {
> struct clk_sam9x5_slow *slowck = to_clk_sam9x5_slow(hw);
>
> - return !!(readl(slowck->sckcr) & AT91_SCKC_OSCSEL);
> + return !!(readl(slowck->sckcr) & slowck->bits->cr_oscsel);
> }
>
> static const struct clk_ops sam9x5_slow_ops = {
> @@ -287,7 +298,8 @@ static struct clk_hw * __init
> at91_clk_register_sam9x5_slow(void __iomem *sckcr,
> const char *name,
> const char **parent_names,
> - int num_parents)
> + int num_parents,
> + const struct clk_slow_bits *bits)
> {
> struct clk_sam9x5_slow *slowck;
> struct clk_hw *hw;
> @@ -309,7 +321,8 @@ at91_clk_register_sam9x5_slow(void __iomem *sckcr,
>
> slowck->hw.init = &init;
> slowck->sckcr = sckcr;
> - slowck->parent = !!(readl(sckcr) & AT91_SCKC_OSCSEL);
> + slowck->bits = bits;
> + slowck->parent = !!(readl(sckcr) & slowck->bits->cr_oscsel);
>
> hw = &slowck->hw;
> ret = clk_hw_register(NULL, &slowck->hw);
> @@ -322,7 +335,8 @@ at91_clk_register_sam9x5_slow(void __iomem *sckcr,
> }
>
> static void __init at91sam9x5_sckc_register(struct device_node *np,
> - unsigned int rc_osc_startup_us)
> + unsigned int rc_osc_startup_us,
> + const struct clk_slow_bits *bits)
> {
> const char *parent_names[2] = { "slow_rc_osc", "slow_osc" };
> void __iomem *regbase = of_iomap(np, 0);
> @@ -335,7 +349,8 @@ static void __init at91sam9x5_sckc_register(struct device_node *np,
> return;
>
> hw = at91_clk_register_slow_rc_osc(regbase, parent_names[0], 32768,
> - 50000000, rc_osc_startup_us);
> + 50000000, rc_osc_startup_us,
> + bits);
> if (IS_ERR(hw))
> return;
>
> @@ -358,11 +373,12 @@ static void __init at91sam9x5_sckc_register(struct device_node *np,
> return;
>
> hw = at91_clk_register_slow_osc(regbase, parent_names[1], xtal_name,
> - 1200000, bypass);
> + 1200000, bypass, bits);
> if (IS_ERR(hw))
> return;
>
> - hw = at91_clk_register_sam9x5_slow(regbase, "slowck", parent_names, 2);
> + hw = at91_clk_register_sam9x5_slow(regbase, "slowck", parent_names, 2,
> + bits);
> if (IS_ERR(hw))
> return;
>
> @@ -373,16 +389,23 @@ static void __init at91sam9x5_sckc_register(struct device_node *np,
> of_clk_add_hw_provider(child, of_clk_hw_simple_get, hw);
> }
>
> +static const struct clk_slow_bits at91sam9x5_bits = {
> + .cr_rcen = BIT(0),
> + .cr_osc32en = BIT(1),
> + .cr_osc32byp = BIT(2),
> + .cr_oscsel = BIT(3),
> +};
> +
> static void __init of_at91sam9x5_sckc_setup(struct device_node *np)
> {
> - at91sam9x5_sckc_register(np, 75);
> + at91sam9x5_sckc_register(np, 75, &at91sam9x5_bits);
> }
> CLK_OF_DECLARE(at91sam9x5_clk_sckc, "atmel,at91sam9x5-sckc",
> of_at91sam9x5_sckc_setup);
>
> static void __init of_sama5d3_sckc_setup(struct device_node *np)
> {
> - at91sam9x5_sckc_register(np, 500);
> + at91sam9x5_sckc_register(np, 500, &at91sam9x5_bits);
> }
> CLK_OF_DECLARE(sama5d3_clk_sckc, "atmel,sama5d3-sckc",
> of_sama5d3_sckc_setup);
> @@ -398,7 +421,7 @@ static int clk_sama5d4_slow_osc_prepare(struct clk_hw *hw)
> * Assume that if it has already been selected (for example by the
> * bootloader), enough time has aready passed.
> */
> - if ((readl(osc->sckcr) & AT91_SCKC_OSCSEL)) {
> + if ((readl(osc->sckcr) & osc->bits->cr_oscsel)) {
> osc->prepared = true;
> return 0;
> }
> @@ -421,6 +444,10 @@ static const struct clk_ops sama5d4_slow_osc_ops = {
> .is_prepared = clk_sama5d4_slow_osc_is_prepared,
> };
>
> +static const struct clk_slow_bits at91sama5d4_bits = {
> + .cr_oscsel = BIT(3),
> +};
> +
> static void __init of_sama5d4_sckc_setup(struct device_node *np)
> {
> void __iomem *regbase = of_iomap(np, 0);
> @@ -455,6 +482,7 @@ static void __init of_sama5d4_sckc_setup(struct device_node *np)
> osc->hw.init = &init;
> osc->sckcr = regbase;
> osc->startup_usec = 1200000;
> + osc->bits = &at91sama5d4_bits;
>
> hw = &osc->hw;
> ret = clk_hw_register(NULL, &osc->hw);
> @@ -463,7 +491,8 @@ static void __init of_sama5d4_sckc_setup(struct device_node *np)
> return;
> }
>
> - hw = at91_clk_register_sam9x5_slow(regbase, "slowck", parent_names, 2);
> + hw = at91_clk_register_sam9x5_slow(regbase, "slowck", parent_names, 2,
> + &at91sama5d4_bits);
> if (IS_ERR(hw))
> return;
>
> --
> 2.7.4
>

--
Alexandre Belloni, Bootlin
Embedded Linux and Kernel engineering
https://bootlin.com