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SubjectRe: [PATCH v2 3/3] ARM: da850: fix da850_set_pll0rate()
Good to see you again Bartosz :)

On 02-12-16, 16:38, Bartosz Golaszewski wrote:
> This function is broken - its second argument is an index to the freq
> table, not the requested clock rate in Hz. It leads to an oops when
> called from clk_set_rate() since this argument isn't bounds checked
> either.
>
> Fix it by iterating over the array of supported frequencies and
> selecting a one that matches or returning -EINVAL for unsupported
> rates.
>
> Also: update the davinci cpufreq driver. It's the only user of this
> clock and currently it passes the cpufreq table index to
> clk_set_rate(), which is confusing. Make it pass the requested clock
> rate in Hz.
>
> Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
> ---
> arch/arm/mach-davinci/da850.c | 22 ++++++++++++++++++----
> drivers/cpufreq/davinci-cpufreq.c | 2 +-
> 2 files changed, 19 insertions(+), 5 deletions(-)
>
> diff --git a/arch/arm/mach-davinci/da850.c b/arch/arm/mach-davinci/da850.c
> index a55101c..92e3303 100644
> --- a/arch/arm/mach-davinci/da850.c
> +++ b/arch/arm/mach-davinci/da850.c
> @@ -1179,14 +1179,28 @@ static int da850_set_armrate(struct clk *clk, unsigned long index)
> return clk_set_rate(pllclk, index);
> }
>
> -static int da850_set_pll0rate(struct clk *clk, unsigned long index)
> +static int da850_set_pll0rate(struct clk *clk, unsigned long rate)
> {
> - unsigned int prediv, mult, postdiv;
> - struct da850_opp *opp;
> struct pll_data *pll = clk->pll_data;
> + struct cpufreq_frequency_table *freq;
> + unsigned int prediv, mult, postdiv;
> + struct da850_opp *opp = NULL;
> int ret;
>
> - opp = (struct da850_opp *) cpufreq_info.freq_table[index].driver_data;
> + for (freq = da850_freq_table;
> + freq->frequency != CPUFREQ_TABLE_END; freq++) {
> + /* requested_rate is in Hz, freq->frequency is in KHz */
> + unsigned long freq_rate = freq->frequency * 1000;
> +
> + if (freq_rate == rate) {
> + opp = (struct da850_opp *)freq->driver_data;
> + break;
> + }
> + }
> +
> + if (opp == NULL)
> + return -EINVAL;
> +
> prediv = opp->prediv;
> mult = opp->mult;
> postdiv = opp->postdiv;
> diff --git a/drivers/cpufreq/davinci-cpufreq.c b/drivers/cpufreq/davinci-cpufreq.c
> index b95a872..d54a27c 100644
> --- a/drivers/cpufreq/davinci-cpufreq.c
> +++ b/drivers/cpufreq/davinci-cpufreq.c
> @@ -55,7 +55,7 @@ static int davinci_target(struct cpufreq_policy *policy, unsigned int idx)
> return ret;
> }
>
> - ret = clk_set_rate(armclk, idx);
> + ret = clk_set_rate(armclk, new_freq * 1000);
> if (ret)
> return ret;

I haven't checked the internal of davinci or the way rate is changed now, but
from cpufreq's perspective, fee free to add my:

Acked-by: Viresh Kumar <viresh.kumar@linaro.org>

--
viresh

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