Re: [PATCH v2 08/15] phy: qcom-qmp-pcie: add register init helper

From: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
To: Johan Hovold <johan@kernel.org>
Cc: Johan Hovold <johan+linaro@kernel.org>,
	Vinod Koul <vkoul@kernel.org>, Andy Gross <agross@kernel.org>,
	Bjorn Andersson <andersson@kernel.org>,
	Konrad Dybcio <konrad.dybcio@somainline.org>,
	Rob Herring <robh+dt@kernel.org>,
	Krzysztof Kozlowski <krzysztof.kozlowski+dt@linaro.org>,
	linux-arm-msm@vger.kernel.org, linux-phy@lists.infradead.org,
	devicetree@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH v2 08/15] phy: qcom-qmp-pcie: add register init helper
Date: Wed, 19 Oct 2022 16:44:33 +0300	[thread overview]
Message-ID: <0b0c752c-1f3d-bf5a-ade7-e2f8acac92a4@linaro.org> (raw)
In-Reply-To: <Y0/63eH82t2zXFi5@hovoldconsulting.com>

On 19/10/2022 16:25, Johan Hovold wrote:
> On Wed, Oct 19, 2022 at 04:12:02PM +0300, Dmitry Baryshkov wrote:
>> On 19/10/2022 14:35, Johan Hovold wrote:
>>> Generalise the serdes initialisation helper so that it can be used to
>>> initialise all the PHY registers (e.g. serdes, tx, rx, pcs).
>>>
>>> Note that this defers the ungating of the PIPE clock somewhat, which is
>>> fine as it isn't needed until starting the PHY.
>>>
>>> Signed-off-by: Johan Hovold <johan+linaro@kernel.org>
>>> ---
>>>    drivers/phy/qualcomm/phy-qcom-qmp-pcie.c | 51 +++++++-----------------
>>>    1 file changed, 15 insertions(+), 36 deletions(-)
>>>
>>> diff --git a/drivers/phy/qualcomm/phy-qcom-qmp-pcie.c b/drivers/phy/qualcomm/phy-qcom-qmp-pcie.c
>>> index dd7e72424fc0..f57d10f20277 100644
>>> --- a/drivers/phy/qualcomm/phy-qcom-qmp-pcie.c
>>> +++ b/drivers/phy/qualcomm/phy-qcom-qmp-pcie.c
>>> @@ -1820,46 +1820,32 @@ static void qmp_pcie_configure(void __iomem *base,
>>>    	qmp_pcie_configure_lane(base, tbl, num, 0xff);
>>>    }
>>>    
>>> -static void qmp_pcie_serdes_init(struct qmp_pcie *qmp, const struct qmp_phy_cfg_tables *tables)
>>> -{
>>> -	void __iomem *serdes = qmp->serdes;
>>> -
>>> -	if (!tables)
>>> -		return;
>>> -
>>> -	qmp_pcie_configure(serdes, tables->serdes, tables->serdes_num);
>>> -}
>>> -
>>> -static void qmp_pcie_lanes_init(struct qmp_pcie *qmp, const struct qmp_phy_cfg_tables *tables)
>>> +static void qmp_pcie_init_registers(struct qmp_pcie *qmp, const struct qmp_phy_cfg_tables *tbls)
>>>    {
>>>    	const struct qmp_phy_cfg *cfg = qmp->cfg;
>>> +	void __iomem *serdes = qmp->serdes;
>>>    	void __iomem *tx = qmp->tx;
>>>    	void __iomem *rx = qmp->rx;
>>>    	void __iomem *tx2 = qmp->tx2;
>>>    	void __iomem *rx2 = qmp->rx2;
>>> +	void __iomem *pcs = qmp->pcs;
>>> +	void __iomem *pcs_misc = qmp->pcs_misc;
>>>    
>>> -	if (!tables)
>>> +	if (!tbls)
>>>    		return;
>>>    
>>> -	qmp_pcie_configure_lane(tx, tables->tx, tables->tx_num, 1);
>>> -	qmp_pcie_configure_lane(rx, tables->rx, tables->rx_num, 1);
>>> +	qmp_pcie_configure(serdes, tbls->serdes, tbls->serdes_num);
>>> +
>>> +	qmp_pcie_configure_lane(tx, tbls->tx, tbls->tx_num, 1);
>>> +	qmp_pcie_configure_lane(rx, tbls->rx, tbls->rx_num, 1);
>>>    
>>>    	if (cfg->lanes >= 2) {
>>> -		qmp_pcie_configure_lane(tx2, tables->tx, tables->tx_num, 2);
>>> -		qmp_pcie_configure_lane(rx2, tables->rx, tables->rx_num, 2);
>>> +		qmp_pcie_configure_lane(tx2, tbls->tx, tbls->tx_num, 2);
>>> +		qmp_pcie_configure_lane(rx2, tbls->rx, tbls->rx_num, 2);
>>>    	}
>>> -}
>>> -
>>> -static void qmp_pcie_pcs_init(struct qmp_pcie *qmp, const struct qmp_phy_cfg_tables *tables)
>>> -{
>>> -	void __iomem *pcs = qmp->pcs;
>>> -	void __iomem *pcs_misc = qmp->pcs_misc;
>>> -
>>> -	if (!tables)
>>> -		return;
>>>    
>>> -	qmp_pcie_configure(pcs, tables->pcs, tables->pcs_num);
>>> -	qmp_pcie_configure(pcs_misc, tables->pcs_misc, tables->pcs_misc_num);
>>> +	qmp_pcie_configure(pcs, tbls->pcs, tbls->pcs_num);
>>> +	qmp_pcie_configure(pcs_misc, tbls->pcs_misc, tbls->pcs_misc_num);
>>
>> Nit: could we please keep it as `tables'?
> 
> I considered that but found that the longer identifier hurt
> readability so I prefer to use "tbls" here.
> 
> Compare
> 
> 	qmp_pcie_configure(serdes, tbls->serdes, tbls->serdes_num);
> 
> 	qmp_pcie_configure_lane(tx, tbls->tx, tbls->tx_num, 1);
> 	qmp_pcie_configure_lane(rx, tbls->rx, tbls->rx_num, 1);
> 
> 	if (cfg->lanes >= 2) {
> 		qmp_pcie_configure_lane(tx2, tbls->tx, tbls->tx_num, 2);
> 		qmp_pcie_configure_lane(rx2, tbls->rx, tbls->rx_num, 2);
> 	}
> 
> 	qmp_pcie_configure(pcs, tbls->pcs, tbls->pcs_num);
> 	qmp_pcie_configure(pcs_misc, tbls->pcs_misc, tbls->pcs_misc_num);
> 
> with
> 
> 	qmp_pcie_configure(serdes, tables->serdes, tables->serdes_num);
> 
> 	qmp_pcie_configure_lane(tx, tables->tx, tables->tx_num, 1);
> 	qmp_pcie_configure_lane(rx, tables->rx, tables->rx_num, 1);
> 
> 	if (cfg->lanes >= 2) {
> 		qmp_pcie_configure_lane(tx2, tables->tx, tables->tx_num, 2);
> 		qmp_pcie_configure_lane(rx2, tables->rx, tables->rx_num, 2);
> 	}
> 
> 	qmp_pcie_configure(pcs, tables->pcs, tables->pcs_num);
> 	qmp_pcie_configure(pcs_misc, tables->pcs_misc, tables->pcs_misc_num);

I'd say, it's up to Vinod. I'd prefer the second version.

-- 
With best wishes
Dmitry