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Message-ID: <d1eb440e-53e4-41f4-8d5b-bc86f9aff32a@collabora.com>
Date: Mon, 5 Feb 2024 16:26:36 +0100
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Subject: Re: [PATCH 2/2] phy: add driver for MediaTek XFI T-PHY
To: Daniel Golle <daniel@makrotopia.org>
Cc: Bc-bocun Chen <bc-bocun.chen@mediatek.com>,
 Chunfeng Yun <chunfeng.yun@mediatek.com>, Vinod Koul <vkoul@kernel.org>,
 Kishon Vijay Abraham I <kishon@kernel.org>, Rob Herring <robh@kernel.org>,
 Krzysztof Kozlowski <krzysztof.kozlowski+dt@linaro.org>,
 Conor Dooley <conor+dt@kernel.org>, Qingfang Deng <dqfext@gmail.com>,
 SkyLake Huang <SkyLake.Huang@mediatek.com>,
 Matthias Brugger <matthias.bgg@gmail.com>,
 Philipp Zabel <p.zabel@pengutronix.de>,
 linux-arm-kernel@lists.infradead.org, linux-mediatek@lists.infradead.org,
 linux-phy@lists.infradead.org, devicetree@vger.kernel.org,
 linux-kernel@vger.kernel.org, netdev@vger.kernel.org
References: <702afb0c1246d95c90b22e57105304028bdd3083.1706823233.git.daniel@makrotopia.org>
 <dd6b40ea1f7f8459a9a2cfe7fa60c1108332ade6.1706823233.git.daniel@makrotopia.org>
 <3e9afc4b-4ad6-412b-bc4d-f3e3b1475657@collabora.com>
 <Zb0ZTNnAa_x47En1@makrotopia.org>
From: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Content-Language: en-US
In-Reply-To: <Zb0ZTNnAa_x47En1@makrotopia.org>
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Il 02/02/24 17:33, Daniel Golle ha scritto:
> Hi Angelo,
> 
> thank you for promptly reviewing my submission and providing valuable
> feedback!
> 
> On Fri, Feb 02, 2024 at 02:21:48PM +0100, AngeloGioacchino Del Regno wrote:
>> Il 01/02/24 22:53, Daniel Golle ha scritto:
>>> Add driver for MediaTek's XFI T-PHY, 10 Gigabit/s Ethernet SerDes PHY
>>> which can be found in the MT7988 SoC.
>>>
>>> The PHY can operates only in PHY_MODE_ETHERNET, the submode is one of
>>> PHY_INTERFACE_MODE_* corresponding to the supported modes:
>>>
>>>    * USXGMII                 \
>>>    * 10GBase-R                }- USXGMII PCS - XGDM  \
>>>    * 5GBase-R                /                        \
>>>                                                        }- Ethernet MAC
>>>    * 2500Base-X              \                        /
>>>    * 1000Base-X               }- LynxI PCS - GDM     /
>>>    * Cisco SGMII (MAC side)  /
>>>
>>> In order to work-around a performance issue present on the first of
>>> two XFI T-PHYs present in MT7988, special tuning is applied which can be
>>> selected by adding the 'mediatek,usxgmii-performance-errata' property to
>>> the device tree node.
>>>
>>> There is no documentation for most registers used for the
>>> analog/tuning part, however, most of the registers have been partially
>>> reverse-engineered from MediaTek's SDK implementation (an opaque
>>> sequence of 32-bit register writes) and descriptions for all relevant
>>> digital registers and bits such as resets and muxes have been supplied
>>> by MediaTek.
>>>
>>> Signed-off-by: Daniel Golle <daniel@makrotopia.org>
>>> ---
>>>    MAINTAINERS                             |   1 +
>>>    drivers/phy/mediatek/Kconfig            |  12 +
>>>    drivers/phy/mediatek/Makefile           |   1 +
>>>    drivers/phy/mediatek/phy-mtk-xfi-tphy.c | 392 ++++++++++++++++++++++++
>>>    4 files changed, 406 insertions(+)
>>>    create mode 100644 drivers/phy/mediatek/phy-mtk-xfi-tphy.c
>>>
>>> diff --git a/MAINTAINERS b/MAINTAINERS
>>> index 52769631bdb1a..52e4192470bd9 100644
>>> --- a/MAINTAINERS
>>> +++ b/MAINTAINERS
>>> @@ -13715,6 +13715,7 @@ L:	netdev@vger.kernel.org
>>>    S:	Maintained
>>>    F:	drivers/net/phy/mediatek-ge-soc.c
>>>    F:	drivers/net/phy/mediatek-ge.c
>>> +F:	drivers/phy/mediatek/phy-mtk-xfi-tphy.c
>>>    MEDIATEK I2C CONTROLLER DRIVER
>>>    M:	Qii Wang <qii.wang@mediatek.com>
>>> diff --git a/drivers/phy/mediatek/Kconfig b/drivers/phy/mediatek/Kconfig
>>> index 3125ecb5d119f..5161d130c7f8b 100644
>>> --- a/drivers/phy/mediatek/Kconfig
>>> +++ b/drivers/phy/mediatek/Kconfig
>>> @@ -13,6 +13,18 @@ config PHY_MTK_PCIE
>>>    	  callback for PCIe GEN3 port, it supports software efuse
>>>    	  initialization.
>>> +config PHY_MTK_XFI_TPHY
>>> +	tristate "MediaTek XFI T-PHY Driver"
>>> +	depends on ARCH_MEDIATEK || COMPILE_TEST
>>> +	depends on OF && OF_ADDRESS
>>> +	depends on HAS_IOMEM
>>> +	select GENERIC_PHY
>>> +	help
>>> +	  Say 'Y' here to add support for MediaTek XFI T-PHY driver.
>>> +	  The driver provides access to the Ethernet SerDes T-PHY supporting
>>> +	  1GE and 2.5GE modes via the LynxI PCS, and 5GE and 10GE modes
>>> +	  via the USXGMII PCS found in MediaTek SoCs with 10G Ethernet.
>>> +
>>>    config PHY_MTK_TPHY
>>>    	tristate "MediaTek T-PHY Driver"
>>>    	depends on ARCH_MEDIATEK || COMPILE_TEST
>>> diff --git a/drivers/phy/mediatek/Makefile b/drivers/phy/mediatek/Makefile
>>> index c9a50395533eb..fa7217178e7f4 100644
>>> --- a/drivers/phy/mediatek/Makefile
>>> +++ b/drivers/phy/mediatek/Makefile
>>> @@ -8,6 +8,7 @@ obj-$(CONFIG_PHY_MTK_PCIE)		+= phy-mtk-pcie.o
>>>    obj-$(CONFIG_PHY_MTK_TPHY)		+= phy-mtk-tphy.o
>>>    obj-$(CONFIG_PHY_MTK_UFS)		+= phy-mtk-ufs.o
>>>    obj-$(CONFIG_PHY_MTK_XSPHY)		+= phy-mtk-xsphy.o
>>> +obj-$(CONFIG_PHY_MTK_XFI_TPHY)		+= phy-mtk-xfi-tphy.o
>>>    phy-mtk-hdmi-drv-y			:= phy-mtk-hdmi.o
>>>    phy-mtk-hdmi-drv-y			+= phy-mtk-hdmi-mt2701.o
>>> diff --git a/drivers/phy/mediatek/phy-mtk-xfi-tphy.c b/drivers/phy/mediatek/phy-mtk-xfi-tphy.c
>>> new file mode 100644
>>> index 0000000000000..d50e6320860e5
>>> --- /dev/null
>>> +++ b/drivers/phy/mediatek/phy-mtk-xfi-tphy.c
>>> @@ -0,0 +1,392 @@
>>> +// SPDX-License-Identifier: GPL-2.0-or-later
>>> +/* MediaTek 10GE SerDes PHY driver
>>
>> MediaTek 10GE SerDes XFI T-PHY driver ?
> 
> Ack. Will unify the name accross all files.
> 
>>
>>> + *
>>> + * Copyright (c) 2024 Daniel Golle <daniel@makrotopia.org>
>>> + *                    Bc-bocun Chen <bc-bocun.chen@mediatek.com>
>>> + * based on mtk_usxgmii.c found in MediaTek's SDK released under GPL-2.0
>>> + * Copyright (c) 2022 MediaTek Inc.
>>> + * Author: Henry Yen <henry.yen@mediatek.com>
>>> + */
>>> +
>>> +#include <linux/module.h>
>>> +#include <linux/device.h>
>>> +#include <linux/platform_device.h>
>>> +#include <linux/of.h>
>>> +#include <linux/io.h>
>>> +#include <linux/clk.h>
>>> +#include <linux/reset.h>
>>> +#include <linux/phy.h>
>>> +#include <linux/phy/phy.h>
>>> +
>>> +#define MTK_XFI_TPHY_NUM_CLOCKS		2
>>> +
>>> +#define REG_DIG_GLB_70			0x0070
>>> +#define  XTP_PCS_RX_EQ_IN_PROGRESS(x)	FIELD_PREP(GENMASK(25, 24), (x))
>>> +#define  XTP_PCS_MODE_MASK		GENMASK(17, 16)
>>> +#define  XTP_PCS_MODE(x)		FIELD_PREP(GENMASK(17, 16), (x))
>>> +#define  XTP_PCS_RST_B			BIT(15)
>>> +#define  XTP_FRC_PCS_RST_B		BIT(14)
>>> +#define  XTP_PCS_PWD_SYNC_MASK		GENMASK(13, 12)
>>> +#define  XTP_PCS_PWD_SYNC(x)		FIELD_PREP(XTP_PCS_PWD_SYNC_MASK, (x))
>>> +#define  XTP_PCS_PWD_ASYNC_MASK		GENMASK(11, 10)
>>> +#define  XTP_PCS_PWD_ASYNC(x)		FIELD_PREP(XTP_PCS_PWD_ASYNC_MASK, (x))
>>> +#define  XTP_FRC_PCS_PWD_ASYNC		BIT(8)
>>> +#define  XTP_PCS_UPDT			BIT(4)
>>> +#define  XTP_PCS_IN_FR_RG		BIT(0)
>>> +
>>> +#define REG_DIG_GLB_F4			0x00f4
>>> +#define  XFI_DPHY_PCS_SEL		BIT(0)
>>> +#define   XFI_DPHY_PCS_SEL_SGMII	FIELD_PREP(XFI_DPHY_PCS_SEL, 1)
>>> +#define   XFI_DPHY_PCS_SEL_USXGMII	FIELD_PREP(XFI_DPHY_PCS_SEL, 0)
>>> +#define  XFI_DPHY_AD_SGDT_FRC_EN	BIT(5)
>>> +
>>> +#define REG_DIG_LN_TRX_40		0x3040
>>> +#define  XTP_LN_FRC_TX_DATA_EN		BIT(29)
>>> +#define  XTP_LN_TX_DATA_EN		BIT(28)
>>> +
>>> +#define REG_DIG_LN_TRX_B0		0x30b0
>>> +#define  XTP_LN_FRC_TX_MACCK_EN		BIT(5)
>>> +#define  XTP_LN_TX_MACCK_EN		BIT(4)
>>> +
>>> +#define REG_ANA_GLB_D0			0x90d0
>>> +#define  XTP_GLB_USXGMII_SEL_MASK	GENMASK(3, 1)
>>> +#define  XTP_GLB_USXGMII_SEL(x)		FIELD_PREP(GENMASK(3, 1), (x))
>>> +#define  XTP_GLB_USXGMII_EN		BIT(0)
>>> +
>>> +struct mtk_xfi_tphy {
>>> +	void __iomem		*base;
>>> +	struct device		*dev;
>>> +	struct reset_control	*reset;
>>> +	struct clk_bulk_data	clocks[MTK_XFI_TPHY_NUM_CLOCKS];
>>> +	bool			da_war;
>>> +};
>>> +
>>> +static void mtk_xfi_tphy_write(struct mtk_xfi_tphy *xfi_tphy, u16 reg,
>>> +			       u32 value)
>>> +{
>>> +	iowrite32(value, xfi_tphy->base + reg);
>>> +}
>>> +
>>> +static void mtk_xfi_tphy_rmw(struct mtk_xfi_tphy *xfi_tphy, u16 reg,
>>> +			     u32 clr, u32 set)
>>> +{
>>> +	u32 val;
>>> +
>>> +	val = ioread32(xfi_tphy->base + reg);
>>> +	val &= ~clr;
>>> +	val |= set;
>>> +	iowrite32(val, xfi_tphy->base + reg);
>>> +}
>>> +
>>> +static void mtk_xfi_tphy_set(struct mtk_xfi_tphy *xfi_tphy, u16 reg,
>>> +			     u32 set)
>>> +{
>>> +	mtk_xfi_tphy_rmw(xfi_tphy, reg, 0, set);
>>> +}
>>> +
>>> +static void mtk_xfi_tphy_clear(struct mtk_xfi_tphy *xfi_tphy, u16 reg,
>>> +			       u32 clr)
>>> +{
>>> +	mtk_xfi_tphy_rmw(xfi_tphy, reg, clr, 0);
>>> +}
>>> +
>>> +static void mtk_xfi_tphy_setup(struct mtk_xfi_tphy *xfi_tphy,
>>> +			       phy_interface_t interface)
>>> +{
>>> +	bool is_2p5g = (interface == PHY_INTERFACE_MODE_2500BASEX);
>>> +	bool is_1g = (interface == PHY_INTERFACE_MODE_1000BASEX ||
>>> +		      interface == PHY_INTERFACE_MODE_SGMII);
>>> +	bool is_10g = (interface == PHY_INTERFACE_MODE_10GBASER ||
>>> +		       interface == PHY_INTERFACE_MODE_USXGMII);
>>> +	bool is_5g = (interface == PHY_INTERFACE_MODE_5GBASER);
>>> +	bool is_xgmii = (is_10g || is_5g);
>>
>> is_usxgmii, I'd say.
> 
> This boolean is mostly used to destinguish which path to use at the
> T-junction of the PHY, ie. up to 2500Base-X goes to LynxI PCS while
> 5GBase-R, 10GBase-R and USXGMII go to USXGMII PCS (which handles all
> three modes and not just USXGMII).
> 
> Calling the boolean 'is_usxgmii' is a bit confusing as it not only
> means (interface == interface == PHY_INTERFACE_MODE_USXGMII) but
> rather also covers (interface == PHY_INTERFACE_MODE_10GBASER) as well
> as (interface == PHY_INTERFACE_MODE_5GBASER) which are not USXGMII.
> 
> Maybe we invert it and call it 'use_lynxi_pcs' instead?
> 

Since you were able to provide such a good explanation of that, I wonder why
you didn't add that as a comment in the code?

That way, there will be no confusion for sure, even if you keep "is_xgmii" :-)

>>
>>> +
>>> +	dev_dbg(xfi_tphy->dev, "setting up for mode %s\n", phy_modes(interface));
>>> +
>>> +	/* Setup PLL setting */
>>> +	mtk_xfi_tphy_rmw(xfi_tphy, 0x9024, 0x100000, is_10g ? 0x0 : 0x100000);
>>> +	mtk_xfi_tphy_rmw(xfi_tphy, 0x2020, 0x202000, is_5g ? 0x202000 : 0x0);
>>> +	mtk_xfi_tphy_rmw(xfi_tphy, 0x2030, 0x500, is_1g ? 0x0 : 0x500);
>>> +	mtk_xfi_tphy_rmw(xfi_tphy, 0x2034, 0xa00, is_1g ? 0x0 : 0xa00);
>>> +	mtk_xfi_tphy_rmw(xfi_tphy, 0x2040, 0x340000, is_1g ? 0x200000 :
>>> +							     0x140000);
>>> +
>>> +	/* Setup RXFE BW setting */
>>> +	mtk_xfi_tphy_rmw(xfi_tphy, 0x50f0, 0xc10, is_1g ? 0x410 :
>>> +							  is_5g ? 0x800 : 0x400);
>>> +	mtk_xfi_tphy_rmw(xfi_tphy, 0x50e0, 0x4000, is_5g ? 0x0 : 0x4000);
>>> +
>>> +	/* Setup RX CDR setting */
>>> +	mtk_xfi_tphy_rmw(xfi_tphy, 0x506c, 0x30000, is_5g ? 0x0 : 0x30000);
>>> +	mtk_xfi_tphy_rmw(xfi_tphy, 0x5070, 0x670000, is_5g ? 0x620000 : 0x50000);
>>> +	mtk_xfi_tphy_rmw(xfi_tphy, 0x5074, 0x180000, is_5g ? 0x180000 : 0x0);
>>> +	mtk_xfi_tphy_rmw(xfi_tphy, 0x5078, 0xf000400, is_5g ? 0x8000000 :
>>> +							      0x7000400);
>>> +	mtk_xfi_tphy_rmw(xfi_tphy, 0x507c, 0x5000500, is_5g ? 0x4000400 :
>>> +							      0x1000100);
>>> +	mtk_xfi_tphy_rmw(xfi_tphy, 0x5080, 0x1410, is_1g ? 0x400 :
>>> +							   is_5g ? 0x1010 : 0x0);
>>> +	mtk_xfi_tphy_rmw(xfi_tphy, 0x5084, 0x30300, is_1g ? 0x30300 :
>>> +							    is_5g ? 0x30100 :
>>> +								    0x100);
>>> +	mtk_xfi_tphy_rmw(xfi_tphy, 0x5088, 0x60200, is_1g ? 0x20200 :
>>> +							 is_5g ? 0x40000 :
>>> +								 0x20000);
>>> +
>>> +	/* Setting RXFE adaptation range setting */
>>> +	mtk_xfi_tphy_rmw(xfi_tphy, 0x50e4, 0xc0000, is_5g ? 0x0 : 0xc0000);
>>> +	mtk_xfi_tphy_rmw(xfi_tphy, 0x50e8, 0x40000, is_5g ? 0x0 : 0x40000);
>>> +	mtk_xfi_tphy_rmw(xfi_tphy, 0x50ec, 0xa00, is_1g ? 0x200 : 0x800);
>>> +	mtk_xfi_tphy_rmw(xfi_tphy, 0x50a8, 0xee0000, is_5g ? 0x800000 :
>>> +							     0x6e0000);
>>> +	mtk_xfi_tphy_rmw(xfi_tphy, 0x6004, 0x190000, is_5g ? 0x0 : 0x190000);
>>> +	if (is_10g)
>>> +		mtk_xfi_tphy_write(xfi_tphy, 0x00f8, 0x01423342);
>>> +	else if (is_5g)
>>> +		mtk_xfi_tphy_write(xfi_tphy, 0x00f8, 0x00a132a1);
>>> +	else if (is_2p5g)
>>> +		mtk_xfi_tphy_write(xfi_tphy, 0x00f8, 0x009c329c);
>>> +	else
>>> +		mtk_xfi_tphy_write(xfi_tphy, 0x00f8, 0x00fa32fa);
>>> +
>>> +	/* Force SGDT_OUT off and select PCS */
>>> +	mtk_xfi_tphy_rmw(xfi_tphy, REG_DIG_GLB_F4,
>>> +			 XFI_DPHY_AD_SGDT_FRC_EN | XFI_DPHY_PCS_SEL,
>>> +			 XFI_DPHY_AD_SGDT_FRC_EN |
>>> +			 (is_xgmii ? XFI_DPHY_PCS_SEL_USXGMII :
>>> +				     XFI_DPHY_PCS_SEL_SGMII));
>>> +
>>> +
>>> +	/* Force GLB_CKDET_OUT */
>>> +	mtk_xfi_tphy_set(xfi_tphy, 0x0030, 0xc00);
>>> +
>>> +	/* Force AEQ on */
>>> +	mtk_xfi_tphy_write(xfi_tphy, REG_DIG_GLB_70,
>>> +			   XTP_PCS_RX_EQ_IN_PROGRESS(2) |
>>> +			   XTP_PCS_PWD_SYNC(2) |
>>> +			   XTP_PCS_PWD_ASYNC(2));
>>> +
>>> +	usleep_range(1, 5);
>>> +
>>> +	/* Setup TX DA default value */
>>> +	mtk_xfi_tphy_rmw(xfi_tphy, 0x30b0, 0x30, 0x20);
>>> +	mtk_xfi_tphy_write(xfi_tphy, 0x3028, 0x00008a01);
>>> +	mtk_xfi_tphy_write(xfi_tphy, 0x302c, 0x0000a884);
>>> +	mtk_xfi_tphy_write(xfi_tphy, 0x3024, 0x00083002);
>>> +
>>> +	/* Setup RG default value */
>>> +	if (is_xgmii) {
>>> +		mtk_xfi_tphy_write(xfi_tphy, 0x3010, 0x00022220);
>>> +		mtk_xfi_tphy_write(xfi_tphy, 0x5064, 0x0f020a01);
>>> +		mtk_xfi_tphy_write(xfi_tphy, 0x50b4, 0x06100600);
>>> +		if (interface == PHY_INTERFACE_MODE_USXGMII)
>>> +			mtk_xfi_tphy_write(xfi_tphy, 0x3048, 0x40704000);
>>> +		else
>>> +			mtk_xfi_tphy_write(xfi_tphy, 0x3048, 0x47684100);
>>> +	} else {
>>> +		mtk_xfi_tphy_write(xfi_tphy, 0x3010, 0x00011110);
>>> +		mtk_xfi_tphy_write(xfi_tphy, 0x3048, 0x40704000);
>>> +	}
>>> +
>>> +	if (is_1g)
>>> +		mtk_xfi_tphy_write(xfi_tphy, 0x3064, 0x0000c000);
>>> +
>>> +	/* Setup RX EQ initial value */
>>> +	mtk_xfi_tphy_rmw(xfi_tphy, 0x3050, 0xa8000000,
>>> +			 (interface != PHY_INTERFACE_MODE_10GBASER) ?
>>> +			  0xa8000000 : 0x0);
>>> +	mtk_xfi_tphy_rmw(xfi_tphy, 0x3054, 0xaa,
>>> +			 (interface != PHY_INTERFACE_MODE_10GBASER) ?
>>> +			  0xaa : 0x0);
>>> +
>>> +	if (is_xgmii)
>>> +		mtk_xfi_tphy_write(xfi_tphy, 0x306c, 0x00000f00);
>>> +	else if (is_2p5g)
>>> +		mtk_xfi_tphy_write(xfi_tphy, 0x306c, 0x22000f00);
>>> +	else
>>> +		mtk_xfi_tphy_write(xfi_tphy, 0x306c, 0x20200f00);
>>> +
>>> +	if (interface == PHY_INTERFACE_MODE_10GBASER && xfi_tphy->da_war)
>>> +		mtk_xfi_tphy_rmw(xfi_tphy, 0xa008, 0x10000, 0x10000);
>>> +
>>> +	mtk_xfi_tphy_rmw(xfi_tphy, 0xa060, 0x50000, is_xgmii ? 0x40000 :
>>> +							       0x50000);
>>> +
>>> +	/* Setup PHYA speed */
>>> +	mtk_xfi_tphy_rmw(xfi_tphy, REG_ANA_GLB_D0,
>>> +			 XTP_GLB_USXGMII_SEL_MASK | XTP_GLB_USXGMII_EN,
>>> +			 is_10g ?  XTP_GLB_USXGMII_SEL(0) :
>>> +			 is_5g ?   XTP_GLB_USXGMII_SEL(1) :
>>> +			 is_2p5g ? XTP_GLB_USXGMII_SEL(2) :
>>> +				   XTP_GLB_USXGMII_SEL(3));
>>> +	mtk_xfi_tphy_set(xfi_tphy, REG_ANA_GLB_D0, XTP_GLB_USXGMII_EN);
>>> +
>>> +	/* Release reset */
>>> +	mtk_xfi_tphy_set(xfi_tphy, REG_DIG_GLB_70,
>>> +			 XTP_PCS_RST_B | XTP_FRC_PCS_RST_B);
>>> +	usleep_range(150, 500);
>>> +
>>> +	/* Switch to P0 */
>>> +	mtk_xfi_tphy_rmw(xfi_tphy, REG_DIG_GLB_70,
>>> +			 XTP_PCS_PWD_SYNC_MASK |
>>> +			 XTP_PCS_PWD_ASYNC_MASK,
>>> +			 XTP_FRC_PCS_PWD_ASYNC |
>>> +			 XTP_PCS_UPDT | XTP_PCS_IN_FR_RG);
>>> +	usleep_range(1, 5);
>>> +
>>> +	mtk_xfi_tphy_clear(xfi_tphy, REG_DIG_GLB_70, XTP_PCS_UPDT);
>>> +	usleep_range(15, 50);
>>> +
>>> +	if (is_xgmii) {
>>> +		/* Switch to Gen3 */
>>> +		mtk_xfi_tphy_rmw(xfi_tphy, REG_DIG_GLB_70,
>>> +				 XTP_PCS_MODE_MASK | XTP_PCS_UPDT,
>>> +				 XTP_PCS_MODE(2) | XTP_PCS_UPDT);
>>> +	} else {
>>> +		/* Switch to Gen2 */
>>> +		mtk_xfi_tphy_rmw(xfi_tphy, REG_DIG_GLB_70,
>>> +				 XTP_PCS_MODE_MASK | XTP_PCS_UPDT,
>>> +				 XTP_PCS_MODE(1) | XTP_PCS_UPDT);
>>> +	}
>>> +	usleep_range(1, 5);
>>> +
>>> +	mtk_xfi_tphy_clear(xfi_tphy, REG_DIG_GLB_70, XTP_PCS_UPDT);
>>> +
>>> +	usleep_range(100, 500);
>>> +
>>> +	/* Enable MAC CK */
>>> +	mtk_xfi_tphy_set(xfi_tphy, REG_DIG_LN_TRX_B0, XTP_LN_TX_MACCK_EN);
>>> +	mtk_xfi_tphy_clear(xfi_tphy, REG_DIG_GLB_F4, XFI_DPHY_AD_SGDT_FRC_EN);
>>> +
>>> +	/* Enable TX data */
>>> +	mtk_xfi_tphy_set(xfi_tphy, REG_DIG_LN_TRX_40,
>>> +			 XTP_LN_FRC_TX_DATA_EN | XTP_LN_TX_DATA_EN);
>>> +	usleep_range(400, 1000);
>>> +}
>>> +
>>> +static int mtk_xfi_tphy_set_mode(struct phy *phy, enum phy_mode mode, int
>>> +				 submode)
>>> +{
>>> +	struct mtk_xfi_tphy *xfi_tphy = phy_get_drvdata(phy);
>>> +
>>> +	if (mode != PHY_MODE_ETHERNET)
>>> +		return -EINVAL;
>>> +
>>> +	switch (submode) {
>>> +	case PHY_INTERFACE_MODE_1000BASEX:
>>
>> fallthrough;
> 
> I don't think so. No other kernel drivers are doing that and also there
> is no compiler warning what-so-ever when matching multiple cases in that
> way.
> 

Right. Just verified. Keep it like that then.

>>
>>> +	case PHY_INTERFACE_MODE_2500BASEX:
>>
>> fallthrough;
>>
>>> +	case PHY_INTERFACE_MODE_SGMII:
>>
>> ... etc :-)
>>
>>> +	case PHY_INTERFACE_MODE_5GBASER:
>>> +	case PHY_INTERFACE_MODE_10GBASER:
>>> +	case PHY_INTERFACE_MODE_USXGMII:
>>
>> Does this PHY support PHY_INTERFACE_MODE_XGMII ?
>>
>>> +		mtk_xfi_tphy_setup(xfi_tphy, submode);
>>> +		return 0;
>>> +	default:
>>> +		return -EINVAL;
>>> +	}
>>> +}
>>> +
>>> +static int mtk_xfi_tphy_reset(struct phy *phy)
>>> +{
>>> +	struct mtk_xfi_tphy *xfi_tphy = phy_get_drvdata(phy);
>>> +
>>> +	reset_control_assert(xfi_tphy->reset);
>>> +	usleep_range(100, 500);
>>> +	reset_control_deassert(xfi_tphy->reset);
>>> +	usleep_range(1, 10);
>>> +
>>> +	return 0;
>>> +}
>>> +
>>> +static int mtk_xfi_tphy_power_on(struct phy *phy)
>>> +{
>>> +	struct mtk_xfi_tphy *xfi_tphy = phy_get_drvdata(phy);
>>> +
>>> +	return clk_bulk_prepare_enable(MTK_XFI_TPHY_NUM_CLOCKS, xfi_tphy->clocks);
>>> +}
>>> +
>>> +static int mtk_xfi_tphy_power_off(struct phy *phy)
>>> +{
>>> +	struct mtk_xfi_tphy *xfi_tphy = phy_get_drvdata(phy);
>>> +
>>> +	clk_bulk_disable_unprepare(MTK_XFI_TPHY_NUM_CLOCKS, xfi_tphy->clocks);
>>> +
>>> +	return 0;
>>> +}
>>> +
>>> +static const struct phy_ops mtk_xfi_tphy_ops = {
>>> +	.power_on	= mtk_xfi_tphy_power_on,
>>> +	.power_off	= mtk_xfi_tphy_power_off,
>>> +	.set_mode	= mtk_xfi_tphy_set_mode,
>>> +	.reset		= mtk_xfi_tphy_reset,
>>> +	.owner		= THIS_MODULE,
>>> +};
>>> +
>>> +static int mtk_xfi_tphy_probe(struct platform_device *pdev)
>>> +{
>>> +	struct device_node *np = pdev->dev.of_node;
>>> +	struct phy_provider *phy_provider;
>>> +	struct mtk_xfi_tphy *xfi_tphy;
>>> +	struct phy *phy;
>>> +
>>> +	if (!np)
>>> +		return -ENODEV;
>>> +
>>> +	xfi_tphy = devm_kzalloc(&pdev->dev, sizeof(*xfi_tphy), GFP_KERNEL);
>>> +	if (!xfi_tphy)
>>> +		return -ENOMEM;
>>> +
>>> +	xfi_tphy->base = devm_of_iomap(&pdev->dev, np, 0, NULL);
>>
>> Why devm_of_iomap() and not devm_platform_ioremap_resource()?
> 
> True, I will make use of devm_platform_ioremap_resource().
> 
>>
>>> +	if (!xfi_tphy->base)
>>> +		return -EIO;
>>> +
>>> +	xfi_tphy->dev = &pdev->dev;
>>> +
>>> +	xfi_tphy->clocks[0].id = "topxtal";
>>
>> xfi_tphy->clocks[0].id = "topxtal";
>> xfi_tphy->clocks[1].id = "xfipll";
>>
>> ret = devm_clk_bulk_get(&pdev->dev, MTK_XFI_TPHY_NUM_CLOCKS, xfi_tphy->clocks);
>> if (ret)
>> 	return ret;
>>
>> ...it's that simple :-P
> 
> Ok, thanks :)
> 
>>
>>> +	xfi_tphy->clocks[0].clk = devm_clk_get(&pdev->dev, xfi_tphy->clocks[0].id);
>>> +	if (IS_ERR(xfi_tphy->clocks[0].clk))
>>> +		return PTR_ERR(xfi_tphy->clocks[0].clk);
>>> +
>>> +	xfi_tphy->clocks[1].id = "xfipll";
>>> +	xfi_tphy->clocks[1].clk = devm_clk_get(&pdev->dev, xfi_tphy->clocks[1].id);
>>> +	if (IS_ERR(xfi_tphy->clocks[1].clk))
>>> +		return PTR_ERR(xfi_tphy->clocks[1].clk);
>>> +
>>> +	xfi_tphy->reset = devm_reset_control_get_exclusive(&pdev->dev, NULL);
>>> +	if (IS_ERR(xfi_tphy->reset))
>>> +		return PTR_ERR(xfi_tphy->reset);
>>> +
>>> +	xfi_tphy->da_war = of_property_read_bool(np,
>>> +						 "mediatek,usxgmii-performance-errata");
>>> +
>>
>> One line please
>>
>>> +	phy = devm_phy_create(&pdev->dev, NULL, &mtk_xfi_tphy_ops);
>>> +	if (IS_ERR(phy))
>>> +		return PTR_ERR(phy);
>>> +
>>> +	phy_set_drvdata(phy, xfi_tphy);
>>> +
>>> +	phy_provider = devm_of_phy_provider_register(&pdev->dev,
>>> +						     of_phy_simple_xlate);
>>
>> ditto
>>
>>> +
>>> +	return PTR_ERR_OR_ZERO(phy_provider);
>>> +}
>>> +
>>> +static const struct of_device_id mtk_xfi_tphy_match[] = {
>>> +	{ .compatible = "mediatek,mt7988-xfi-tphy", },
>>> +	{ }
>>
>> 	{ .compatible = "mediatek,mt7988-xfi-tphy" },
>> 	{ /* sentinel */ }
> 
> Ack.
> 
>>
>>> +};
>>> +MODULE_DEVICE_TABLE(of, mtk_xfi_tphy_match);
>>> +
>>> +static struct platform_driver mtk_xfi_tphy_driver = {
>>> +	.probe = mtk_xfi_tphy_probe,
>>> +	.driver = {
>>> +		.name = "mtk-xfi-tphy",
>>> +		.of_match_table = mtk_xfi_tphy_match,
>>> +	},
>>> +};
>>> +module_platform_driver(mtk_xfi_tphy_driver);
>>> +
>>> +MODULE_DESCRIPTION("MediaTek XFI T-PHY driver");
>>
>> MODULE_DESCRIPTION("MediaTek 10GE SerDes XFI T-PHY driver");
> 
> Ack, will unify the name everywhere.
> 
>>
>> Cheers,
>> Angelo
>>
>>> +MODULE_AUTHOR("Daniel Golle <daniel@makrotopia.org>");
>>> +MODULE_AUTHOR("Bc-bocun Chen <bc-bocun.chen@mediatek.com>");
>>> +MODULE_LICENSE("GPL");
>>
>>