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Groups > linux.kernel > #1700810
| From | Sylwester Nawrocki <s.nawrocki@samsung.com> |
|---|---|
| Newsgroups | linux.kernel |
| Subject | Re: [PATCH] clk: samsung: exynos5420: The EPLL rate table corrections |
| Date | 2017-08-01 12:20 +0200 |
| Message-ID | <u9Cro-2tI-3@gated-at.bofh.it> (permalink) |
| References | <u5Ei6-4ce-27@gated-at.bofh.it> <u5Ei6-4ce-25@gated-at.bofh.it> <u9hZF-6eS-31@gated-at.bofh.it> <u9pku-2jJ-7@gated-at.bofh.it> |
| Organization | linux.* mail to news gateway |
On 07/31/2017 10:17 PM, Stephen Boyd wrote:
> On 07/31, Sylwester Nawrocki wrote:
>> On 07/21/2017 01:19 PM, Sylwester Nawrocki wrote:
>>> This patch fixes values of the EPLL K coefficient and changes
>>> the EPLL output frequency values to match exactly what is
>>> possible to achieve with given M, P, S, K coefficients.
>>> This allows to avoid rounding errors and unexpected frequency
>>> being set with clk_set_rate(), due to recalc_rate returning
>>> different values than the PLL rate specified in the
>>> exynos5420_epll_24mhz_tbl table. E.g. this prevents a case
>>> where two consecutive clk_set_rate() calls with same argument
>>> result in different PLL output frequency.
>>>
>>> The PLL output frequencies have been calculated with formula:
>>>
>>> f = fxtal * (M * 2^16 + K) / (P * 2^S) / 2^16
>>>
>>> where fxtal = 24000000.
>>>
>>> Fixes: 9842452acd ("clk: samsung: exynos542x: Add EPLL rate table")
>>> Signed-off-by: Sylwester Nawrocki<s.nawrocki@samsung.com>
>> Stephen, Mike,
>>
>> Could you apply this patch directly for v4.12-rcX?
>> It fixes code added in v4.12.
>>
> You mean v4.13? Sure.
Yes, apologies for confusing these numbers. Thanks for taking
care of the patch.
--
Regards,
Sylwester
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Re: [PATCH] clk: samsung: exynos5420: The EPLL rate table corrections Stephen Boyd <sboyd@codeaurora.org> - 2017-07-31 22:20 +0200 Re: [PATCH] clk: samsung: exynos5420: The EPLL rate table corrections Sylwester Nawrocki <s.nawrocki@samsung.com> - 2017-08-01 12:20 +0200
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