From: Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com>
To: Yong Wu <yong.wu@mediatek.com>
Cc: Rob Herring <robh+dt@kernel.org>,
Matthias Brugger <matthias.bgg@gmail.com>,
Krzysztof Kozlowski <krzk@kernel.org>,
Joerg Roedel <joro@8bytes.org>, Will Deacon <will@kernel.org>,
Robin Murphy <robin.murphy@arm.com>,
Tomasz Figa <tfiga@chromium.org>,
linux-mediatek@lists.infradead.org, srv_heupstream@mediatek.com,
linux-kernel@vger.kernel.org,
linux-arm-kernel@lists.infradead.org,
iommu@lists.linux-foundation.org, youlin.pei@mediatek.com,
anan.sun@mediatek.com, ming-fan.chen@mediatek.com,
yi.kuo@mediatek.com, anthony.huang@mediatek.com
Subject: Re: [PATCH 3/9] memory: mtk-smi: Use clk_bulk instead of the clk ops
Date: Mon, 12 Jul 2021 08:44:47 +0200 [thread overview]
Message-ID: <fe426c10-4cfe-103c-9961-1b8fdb18a16a@canonical.com> (raw)
In-Reply-To: <1625992199.22309.15.camel@mhfsdcap03>
On 11/07/2021 10:29, Yong Wu wrote:
> On Thu, 2021-07-08 at 11:32 +0200, Krzysztof Kozlowski wrote:
>> On 16/06/2021 13:43, Yong Wu wrote:
>>> smi have many clocks: apb/smi/gals.
>>> This patch use clk_bulk interface instead of the orginal one to simply
>>> the code.
>>>
>>> gals is optional clk(some larbs may don't have gals). use clk_bulk_optional
>>> instead. and then remove the has_gals flag.
>>>
>>> Also remove clk fail logs since bulk interface already output fail log.
>>>
>>> Signed-off-by: Yong Wu <yong.wu@mediatek.com>
>>> ---
>>> drivers/memory/mtk-smi.c | 124 +++++++++++----------------------------
>>> 1 file changed, 34 insertions(+), 90 deletions(-)
>>>
>>> diff --git a/drivers/memory/mtk-smi.c b/drivers/memory/mtk-smi.c
>>> index c5fb51f73b34..bcd2bf130655 100644
>>> --- a/drivers/memory/mtk-smi.c
>>> +++ b/drivers/memory/mtk-smi.c
>>> @@ -60,9 +60,18 @@ enum mtk_smi_gen {
>>> MTK_SMI_GEN2
>>> };
>>>
>>> +#define MTK_SMI_CLK_NR_MAX 4
>>> +
>>> +static const char * const mtk_smi_common_clocks[] = {
>>> + "apb", "smi", "gals0", "gals1", /* glas is optional */
>>
>> Typo here - glas.
>
> Will Fix. Thanks.
>
>>
>>> +};
>>> +
>
> [snip]
>
>>> @@ -493,7 +449,7 @@ static int mtk_smi_common_probe(struct platform_device *pdev)
>>> struct device *dev = &pdev->dev;
>>> struct mtk_smi *common;
>>> struct resource *res;
>>> - int ret;
>>> + int i, ret;
>>>
>>> common = devm_kzalloc(dev, sizeof(*common), GFP_KERNEL);
>>> if (!common)
>>> @@ -501,23 +457,13 @@ static int mtk_smi_common_probe(struct platform_device *pdev)
>>> common->dev = dev;
>>> common->plat = of_device_get_match_data(dev);
>>>
>>> - common->clk_apb = devm_clk_get(dev, "apb");
>>> - if (IS_ERR(common->clk_apb))
>>> - return PTR_ERR(common->clk_apb);
>>> -
>>> - common->clk_smi = devm_clk_get(dev, "smi");
>>> - if (IS_ERR(common->clk_smi))
>>> - return PTR_ERR(common->clk_smi);
>>> + common->clk_num = ARRAY_SIZE(mtk_smi_common_clocks);
>>> + for (i = 0; i < common->clk_num; i++)
>>> + common->clks[i].id = mtk_smi_common_clocks[i];
>>>
>>> - if (common->plat->has_gals) {
>>> - common->clk_gals0 = devm_clk_get(dev, "gals0");
>>> - if (IS_ERR(common->clk_gals0))
>>> - return PTR_ERR(common->clk_gals0);
>>> -
>>> - common->clk_gals1 = devm_clk_get(dev, "gals1");
>>> - if (IS_ERR(common->clk_gals1))
>>> - return PTR_ERR(common->clk_gals1);
>>> - }
>>> + ret = devm_clk_bulk_get_optional(dev, common->clk_num, common->clks);
>>> + if (ret)
>>> + return ret;
>>
>> How do you handle now missing required clocks?
>
> It looks this is a common issue for this function which supports all the
> clocks could be optional. Is there common suggestion for this?
>
> For our case, the apb/smi clocks are required while "gals" are optional.
>
> thus, we should use devm_clk_bulk_get for the necessary clocks and
> devm_clk_bulk_get_optional for the optional ones. right?
Yes, I think that's the solution. Otherwise you might not have proper
clocks leading to accesses to disabled/gated hardware.
Best regards,
Krzysztof
_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
next prev parent reply other threads:[~2021-07-12 6:46 UTC|newest]
Thread overview: 18+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-06-16 11:43 [PATCH 0/9] MT8195 SMI support Yong Wu
2021-06-16 11:43 ` [PATCH 1/9] dt-bindings: memory: mediatek: Add mt8195 smi binding Yong Wu
2021-07-08 9:26 ` Krzysztof Kozlowski
2021-07-11 8:24 ` Yong Wu
2021-06-16 11:43 ` [PATCH 2/9] dt-bindings: memory: mediatek: Add mt8195 smi sub common Yong Wu
2021-06-16 11:43 ` [PATCH 3/9] memory: mtk-smi: Use clk_bulk instead of the clk ops Yong Wu
2021-07-08 9:32 ` Krzysztof Kozlowski
2021-07-11 8:29 ` Yong Wu
2021-07-12 6:44 ` Krzysztof Kozlowski [this message]
2021-06-16 11:43 ` [PATCH 4/9] memory: mtk-smi: Rename smi_gen to smi_type Yong Wu
2021-07-08 9:34 ` Krzysztof Kozlowski
2021-07-11 8:24 ` Yong Wu
2021-06-16 11:43 ` [PATCH 5/9] memory: mtk-smi: Adjust some code position Yong Wu
2021-06-16 11:43 ` [PATCH 6/9] memory: mtk-smi: Add smi sub common support Yong Wu
2021-07-08 9:47 ` Krzysztof Kozlowski
2021-06-16 11:43 ` [PATCH 7/9] memory: mtk-smi: mt8195: Add smi support Yong Wu
2021-06-16 11:43 ` [PATCH 8/9] memory: mtk-smi: mt8195: Add initial setting for smi-common Yong Wu
2021-06-16 11:43 ` [PATCH 9/9] memory: mtk-smi: mt8195: Add initial setting for smi-larb Yong Wu
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=fe426c10-4cfe-103c-9961-1b8fdb18a16a@canonical.com \
--to=krzysztof.kozlowski@canonical.com \
--cc=anan.sun@mediatek.com \
--cc=anthony.huang@mediatek.com \
--cc=iommu@lists.linux-foundation.org \
--cc=joro@8bytes.org \
--cc=krzk@kernel.org \
--cc=linux-arm-kernel@lists.infradead.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-mediatek@lists.infradead.org \
--cc=matthias.bgg@gmail.com \
--cc=ming-fan.chen@mediatek.com \
--cc=robh+dt@kernel.org \
--cc=robin.murphy@arm.com \
--cc=srv_heupstream@mediatek.com \
--cc=tfiga@chromium.org \
--cc=will@kernel.org \
--cc=yi.kuo@mediatek.com \
--cc=yong.wu@mediatek.com \
--cc=youlin.pei@mediatek.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).