Re: [PATCH 1/2] ARM: shmobile: sh73a0: do not overwrite all div4 clock operations

[Simon Horman <horms@verge.net.au>]

On Thu, May 23, 2013 at 12:09:36AM +0200, Guennadi Liakhovetski wrote:
> An earlier commit "ARM: shmobile: sh73a0: add support for adjusting CPU
> frequency" intended to replace some clock operations only for the Z-clock,
> instead it replaced them for all div4 clocks, since all div4 clocks share
> the same copy of clock operations. Fix this by using a separate clock
> operations structure for Z-clock.
> 
> Signed-off-by: Guennadi Liakhovetski <g.liakhovetski+renesas@gmail.com>
> ---
> 
> Simon, this fixes a commit, currently in "next." Alternatively, it can be 
> merged with the problematic commit, mentioned in the text above.

Thanks Guennadi,

I will queue this up in the soc-sh73a0 branch for v3.11.
I'm not planning to squash it into the problematic commit at this stage.

> 
>  arch/arm/mach-shmobile/clock-sh73a0.c |   28 +++++++++++++++-------------
>  1 files changed, 15 insertions(+), 13 deletions(-)
> 
> diff --git a/arch/arm/mach-shmobile/clock-sh73a0.c b/arch/arm/mach-shmobile/clock-sh73a0.c
> index 711ecf1..8cb6738 100644
> --- a/arch/arm/mach-shmobile/clock-sh73a0.c
> +++ b/arch/arm/mach-shmobile/clock-sh73a0.c
> @@ -257,9 +257,8 @@ static struct clk twd_clk = {
>  	.ops = &twd_clk_ops,
>  };
>  
> -static int (*div4_set_rate)(struct clk *clk, unsigned long rate);
> -static unsigned long (*div4_recalc)(struct clk *clk);
> -static long (*div4_round_rate)(struct clk *clk, unsigned long rate);
> +static struct sh_clk_ops zclk_ops;
> +static const struct sh_clk_ops *div4_clk_ops;
>  
>  static int zclk_set_rate(struct clk *clk, unsigned long rate)
>  {
> @@ -277,7 +276,7 @@ static int zclk_set_rate(struct clk *clk, unsigned long rate)
>  		/* 1:1 - switch off divider */
>  		__raw_writel(__raw_readl(FRQCRB) & ~(1 << 28), FRQCRB);
>  		/* nullify the divider to prepare for the next time */
> -		ret = div4_set_rate(clk, rate / 2);
> +		ret = div4_clk_ops->set_rate(clk, rate / 2);
>  		if (!ret)
>  			ret = frqcr_kick();
>  		if (ret > 0)
> @@ -292,7 +291,7 @@ static int zclk_set_rate(struct clk *clk, unsigned long rate)
>  			 * set the divider - call the DIV4 method, it will kick
>  			 * FRQCRB too
>  			 */
> -			ret = div4_set_rate(clk, rate);
> +			ret = div4_clk_ops->set_rate(clk, rate);
>  		if (ret < 0)
>  			goto esetrate;
>  	}
> @@ -304,7 +303,7 @@ esetrate:
>  
>  static long zclk_round_rate(struct clk *clk, unsigned long rate)
>  {
> -	unsigned long div_freq = div4_round_rate(clk, rate),
> +	unsigned long div_freq = div4_clk_ops->round_rate(clk, rate),
>  		parent_freq = clk_get_rate(clk->parent);
>  
>  	if (rate > div_freq && abs(parent_freq - rate) < rate - div_freq)
> @@ -319,7 +318,7 @@ static unsigned long zclk_recalc(struct clk *clk)
>  	 * Must recalculate frequencies in case PLL0 has been changed, even if
>  	 * the divisor is unused ATM!
>  	 */
> -	unsigned long div_freq = div4_recalc(clk);
> +	unsigned long div_freq = div4_clk_ops->recalc(clk);
>  
>  	if (__raw_readl(FRQCRB) & (1 << 28))
>  		return div_freq;
> @@ -329,13 +328,16 @@ static unsigned long zclk_recalc(struct clk *clk)
>  
>  static void zclk_extend(void)
>  {
> +	div4_clk_ops = div4_clks[DIV4_Z].ops;
> +
>  	/* We extend the DIV4 clock with a 1:1 pass-through case */
> -	div4_set_rate = div4_clks[DIV4_Z].ops->set_rate;
> -	div4_round_rate = div4_clks[DIV4_Z].ops->round_rate;
> -	div4_recalc = div4_clks[DIV4_Z].ops->recalc;
> -	div4_clks[DIV4_Z].ops->set_rate = zclk_set_rate;
> -	div4_clks[DIV4_Z].ops->round_rate = zclk_round_rate;
> -	div4_clks[DIV4_Z].ops->recalc = zclk_recalc;
> +	zclk_ops = *div4_clk_ops;
> +
> +	zclk_ops.set_rate = zclk_set_rate;
> +	zclk_ops.round_rate = zclk_round_rate;
> +	zclk_ops.recalc = zclk_recalc;
> +
> +	div4_clks[DIV4_Z].ops = &zclk_ops;
>  }
>  
>  enum { DIV6_VCK1, DIV6_VCK2, DIV6_VCK3, DIV6_ZB1,
> -- 
> 1.7.2.5
>