Subject: Re: [PATCH] clk: samsung: exynos5420: The EPLL rate table
 corrections
To: Stephen Boyd <sboyd@codeaurora.org>
Cc: mturquette@baylibre.com, cw00.choi@samsung.com, krzk@kernel.org,
        linux-samsung-soc@vger.kernel.org, linux-clk@vger.kernel.org,
        b.zolnierkie@samsung.com, linux-kernel@vger.kernel.org
From: Sylwester Nawrocki <s.nawrocki@samsung.com>
Message-id: <819c4977-bc4d-38e1-07e0-4f1a620ab3b5@samsung.com>
Date: Tue, 01 Aug 2017 12:14:07 +0200
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References: <CGME20170721112008epcas5p1eb75e4eb00d1dbad130460d2cbc0ce0c@epcas5p1.samsung.com>
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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