Re: [PATCH 1/2] clk: keystone: add support for post divider register for main pll

[Murali Karicheri <m-karicheri2@ti.com>]

On 05/29/2015 12:04 PM, Murali Karicheri wrote:
> Main PLL controller has post divider bits in a separate register in
> pll controller. Use the value from this register instead of fixed
> divider when available.
>
> Signed-off-by: Murali Karicheri <m-karicheri2@ti.com>
> ---
>   .../devicetree/bindings/clock/keystone-pll.txt       |  8 ++++----
>   drivers/clk/keystone/pll.c                           | 20 ++++++++++++++++++--
>   2 files changed, 22 insertions(+), 6 deletions(-)
>
> diff --git a/Documentation/devicetree/bindings/clock/keystone-pll.txt b/Documentation/devicetree/bindings/clock/keystone-pll.txt
> index 225990f..47570d2 100644
> --- a/Documentation/devicetree/bindings/clock/keystone-pll.txt
> +++ b/Documentation/devicetree/bindings/clock/keystone-pll.txt
> @@ -15,8 +15,8 @@ Required properties:
>   - compatible : shall be "ti,keystone,main-pll-clock" or "ti,keystone,pll-clock"
>   - clocks : parent clock phandle
>   - reg - pll control0 and pll multipler registers
> -- reg-names : control and multiplier. The multiplier is applicable only for
> -		main pll clock
> +- reg-names : control, multiplier and post-divider. The multiplier and
> +		post-divider registers are applicable only for main pll clock
>   - fixed-postdiv : fixed post divider value. If absent, use clkod register bits
>   		for postdiv
>
> @@ -25,8 +25,8 @@ Example:
>   		#clock-cells = <0>;
>   		compatible = "ti,keystone,main-pll-clock";
>   		clocks = <&refclksys>;
> -		reg = <0x02620350 4>, <0x02310110 4>;
> -		reg-names = "control", "multiplier";
> +		reg = <0x02620350 4>, <0x02310110 4>, <0x02310108 4>;
> +		reg-names = "control", "multiplier", "post-divider";
>   		fixed-postdiv = <2>;
>   	};
>
> diff --git a/drivers/clk/keystone/pll.c b/drivers/clk/keystone/pll.c
> index 0dd8a4b..4a375ea 100644
> --- a/drivers/clk/keystone/pll.c
> +++ b/drivers/clk/keystone/pll.c
> @@ -37,7 +37,8 @@
>    *	Main PLL or any other PLLs in the device such as ARM PLL, DDR PLL
>    *	or PA PLL available on keystone2. These PLLs are controlled by
>    *	this register. Main PLL is controlled by a PLL controller.
> - * @pllm: PLL register map address
> + * @pllm: PLL register map address for multiplier bits
> + * @pllod: PLL register map address for post divider bits
>    * @pll_ctl0: PLL controller map address
>    * @pllm_lower_mask: multiplier lower mask
>    * @pllm_upper_mask: multiplier upper mask
> @@ -53,6 +54,7 @@ struct clk_pll_data {
>   	u32 phy_pllm;
>   	u32 phy_pll_ctl0;
>   	void __iomem *pllm;
> +	void __iomem *pllod;
>   	void __iomem *pll_ctl0;
>   	u32 pllm_lower_mask;
>   	u32 pllm_upper_mask;
> @@ -102,7 +104,11 @@ static unsigned long clk_pllclk_recalc(struct clk_hw *hw,
>   		/* read post divider from od bits*/
>   		postdiv = ((val & pll_data->clkod_mask) >>
>   				 pll_data->clkod_shift) + 1;
> -	else
> +	else if (pll_data->pllod) {
> +		postdiv = readl(pll_data->pllod);
> +		postdiv = ((postdiv & pll_data->clkod_mask) >>
> +				pll_data->clkod_shift) + 1;
> +	} else
>   		postdiv = pll_data->postdiv;
>
>   	rate /= (prediv + 1);
> @@ -172,12 +178,21 @@ static void __init _of_pll_clk_init(struct device_node *node, bool pllctrl)
>   		/* assume the PLL has output divider register bits */
>   		pll_data->clkod_mask = CLKOD_MASK;
>   		pll_data->clkod_shift = CLKOD_SHIFT;
> +
> +		/*
> +		 * Check if there is an post-divider register. If not
> +		 * assume od bits are part of control register.
> +		 */
> +		i = of_property_match_string(node, "reg-names",
> +					     "post-divider");
> +		pll_data->pllod = of_iomap(node, i);
>   	}
>
>   	i = of_property_match_string(node, "reg-names", "control");
>   	pll_data->pll_ctl0 = of_iomap(node, i);
>   	if (!pll_data->pll_ctl0) {
>   		pr_err("%s: ioremap failed\n", __func__);
> +		iounmap(pll_data->pllod);
>   		goto out;
>   	}
>
> @@ -193,6 +208,7 @@ static void __init _of_pll_clk_init(struct device_node *node, bool pllctrl)
>   		pll_data->pllm = of_iomap(node, i);
>   		if (!pll_data->pllm) {
>   			iounmap(pll_data->pll_ctl0);
> +			iounmap(pll_data->pllod);
>   			goto out;
>   		}
>   	}
>
DT and CLK maintainers,

A gentle reminder to review and provide your comments or acks.

Thanks and regards,

-- 
Murali Karicheri
Linux Kernel, Keystone