[PATCH 1/2] phy: core: add debugfs root

[PATCH 1/2] phy: core: add debugfs root

[Chunfeng Yun]

Add a debugfs root for phy class, then phy drivers can add debugfs files
under this folder.

Signed-off-by: Chunfeng Yun <chunfeng.yun@mediatek.com>
---
 drivers/phy/phy-core.c  | 6 ++++++
 include/linux/phy/phy.h | 2 ++
 2 files changed, 8 insertions(+)

diff --git a/drivers/phy/phy-core.c b/drivers/phy/phy-core.c
index d93ddf1262c5..2f9f69190519 100644
--- a/drivers/phy/phy-core.c
+++ b/drivers/phy/phy-core.c
@@ -11,6 +11,7 @@
 #include <linux/export.h>
 #include <linux/module.h>
 #include <linux/err.h>
+#include <linux/debugfs.h>
 #include <linux/device.h>
 #include <linux/slab.h>
 #include <linux/of.h>
@@ -1204,6 +1205,9 @@ void devm_of_phy_provider_unregister(struct device *dev,
 }
 EXPORT_SYMBOL_GPL(devm_of_phy_provider_unregister);
 
+struct dentry *phy_debug_root;
+EXPORT_SYMBOL_GPL(phy_debug_root);
+
 /**
  * phy_release() - release the phy
  * @dev: the dev member within phy
@@ -1233,6 +1237,8 @@ static int __init phy_core_init(void)
 
 	phy_class->dev_release = phy_release;
 
+	phy_debug_root = debugfs_create_dir("phy", NULL);
+
 	return 0;
 }
 device_initcall(phy_core_init);
diff --git a/include/linux/phy/phy.h b/include/linux/phy/phy.h
index b1413757fcc3..c398749d49b9 100644
--- a/include/linux/phy/phy.h
+++ b/include/linux/phy/phy.h
@@ -205,6 +205,8 @@ struct phy_lookup {
 #define devm_of_phy_provider_register_full(dev, children, xlate) \
 	__devm_of_phy_provider_register(dev, children, THIS_MODULE, xlate)
 
+extern struct dentry *phy_debug_root;
+
 static inline void phy_set_drvdata(struct phy *phy, void *data)
 {
 	dev_set_drvdata(&phy->dev, data);
-- 
2.18.0

[PATCH 2/2] phy: mediatek: tphy: add debugfs files

[Chunfeng Yun]

These debugfs files are mainly used to make eye diagram test easier,
especially helpful to do HQA test for a new IC without efuse enabled.

Signed-off-by: Chunfeng Yun <chunfeng.yun@mediatek.com>
---
 drivers/phy/mediatek/phy-mtk-tphy.c | 375 +++++++++++++++++++++++++++-
 1 file changed, 374 insertions(+), 1 deletion(-)

diff --git a/drivers/phy/mediatek/phy-mtk-tphy.c b/drivers/phy/mediatek/phy-mtk-tphy.c
index e906a82791bd..42cec5f22819 100644
--- a/drivers/phy/mediatek/phy-mtk-tphy.c
+++ b/drivers/phy/mediatek/phy-mtk-tphy.c
@@ -7,6 +7,7 @@
 
 #include <dt-bindings/phy/phy.h>
 #include <linux/clk.h>
+#include <linux/debugfs.h>
 #include <linux/delay.h>
 #include <linux/iopoll.h>
 #include <linux/mfd/syscon.h>
@@ -264,6 +265,8 @@
 
 #define TPHY_CLKS_CNT	2
 
+#define USER_BUF_LEN(count) min_t(size_t, 8, (count))
+
 enum mtk_phy_version {
 	MTK_PHY_V1 = 1,
 	MTK_PHY_V2,
@@ -310,6 +313,7 @@ struct mtk_phy_instance {
 	struct clk_bulk_data clks[TPHY_CLKS_CNT];
 	u32 index;
 	u32 type;
+	struct dentry *dbgfs;
 	struct regmap *type_sw;
 	u32 type_sw_reg;
 	u32 type_sw_index;
@@ -332,10 +336,360 @@ struct mtk_tphy {
 	const struct mtk_phy_pdata *pdata;
 	struct mtk_phy_instance **phys;
 	int nphys;
+	struct dentry *dbgfs_root;
 	int src_ref_clk; /* MHZ, reference clock for slew rate calibrate */
 	int src_coef; /* coefficient for slew rate calibrate */
 };
 
+enum u2_phy_params {
+	U2P_EYE_VRT = 0,
+	U2P_EYE_TERM,
+	U2P_EFUSE_EN,
+	U2P_EFUSE_INTR,
+	U2P_DISCTH,
+	U2P_PRE_EMPHASIS,
+};
+
+enum u3_phy_params {
+	U3P_EFUSE_EN = 0,
+	U3P_EFUSE_INTR,
+	U3P_EFUSE_TX_IMP,
+	U3P_EFUSE_RX_IMP,
+};
+
+static const char *const u2_phy_files[] = {
+	[U2P_EYE_VRT] = "vrt",
+	[U2P_EYE_TERM] = "term",
+	[U2P_EFUSE_EN] = "efuse",
+	[U2P_EFUSE_INTR] = "intr",
+	[U2P_DISCTH] = "discth",
+	[U2P_PRE_EMPHASIS] = "preemph",
+};
+
+static const char *const u3_phy_files[] = {
+	[U3P_EFUSE_EN] = "efuse",
+	[U3P_EFUSE_INTR] = "intr",
+	[U3P_EFUSE_TX_IMP] = "tx-imp",
+	[U3P_EFUSE_RX_IMP] = "rx-imp",
+};
+
+static int u2_phy_params_show(struct seq_file *sf, void *unused)
+{
+	struct mtk_phy_instance *inst = sf->private;
+	const char *fname = file_dentry(sf->file)->d_iname;
+	struct u2phy_banks *u2_banks = &inst->u2_banks;
+	void __iomem *com = u2_banks->com;
+	u32 max = 0;
+	u32 tmp = 0;
+	u32 val = 0;
+	int ret;
+
+	ret = match_string(u2_phy_files, ARRAY_SIZE(u2_phy_files), fname);
+	if (ret < 0)
+		return ret;
+
+	switch (ret) {
+	case U2P_EYE_VRT:
+		tmp = readl(com + U3P_USBPHYACR1);
+		val = FIELD_GET(PA1_RG_VRT_SEL, tmp);
+		max = FIELD_MAX(PA1_RG_VRT_SEL);
+		break;
+
+	case U2P_EYE_TERM:
+		tmp = readl(com + U3P_USBPHYACR1);
+		val = FIELD_GET(PA1_RG_TERM_SEL, tmp);
+		max = FIELD_MAX(PA1_RG_TERM_SEL);
+		break;
+
+	case U2P_EFUSE_EN:
+		if (u2_banks->misc) {
+			tmp = readl(u2_banks->misc + U3P_MISC_REG1);
+			max = 1;
+		}
+
+		val = !!(tmp & MR1_EFUSE_AUTO_LOAD_DIS);
+		break;
+
+	case U2P_EFUSE_INTR:
+		tmp = readl(com + U3P_USBPHYACR1);
+		val = FIELD_GET(PA1_RG_INTR_CAL, tmp);
+		max = FIELD_MAX(PA1_RG_INTR_CAL);
+		break;
+
+	case U2P_DISCTH:
+		tmp = readl(com + U3P_USBPHYACR6);
+		val = FIELD_GET(PA6_RG_U2_DISCTH, tmp);
+		max = FIELD_MAX(PA6_RG_U2_DISCTH);
+		break;
+
+	case U2P_PRE_EMPHASIS:
+		tmp = readl(com + U3P_USBPHYACR6);
+		val = FIELD_GET(PA6_RG_U2_PRE_EMP, tmp);
+		max = FIELD_MAX(PA6_RG_U2_PRE_EMP);
+		break;
+
+	default:
+		seq_printf(sf, "invalid, %d\n", ret);
+		break;
+	}
+
+	seq_printf(sf, "%s : %d [0, %d]\n", fname, val, max);
+
+	return 0;
+}
+
+static int u2_phy_params_open(struct inode *inode, struct file *file)
+{
+	return single_open(file, u2_phy_params_show, inode->i_private);
+}
+
+static ssize_t u2_phy_params_write(struct file *file, const char __user *ubuf,
+				   size_t count, loff_t *ppos)
+{
+	const char *fname = file_dentry(file)->d_iname;
+	struct seq_file *sf = file->private_data;
+	struct mtk_phy_instance *inst = sf->private;
+	struct u2phy_banks *u2_banks = &inst->u2_banks;
+	void __iomem *com = u2_banks->com;
+	ssize_t rc;
+	u32 val;
+	int ret;
+
+	rc = kstrtouint_from_user(ubuf, USER_BUF_LEN(count), 0, &val);
+	if (rc)
+		return rc;
+
+	ret = match_string(u2_phy_files, ARRAY_SIZE(u2_phy_files), fname);
+	if (ret < 0)
+		return (ssize_t)ret;
+
+	switch (ret) {
+	case U2P_EYE_VRT:
+		mtk_phy_update_field(com + U3P_USBPHYACR1, PA1_RG_VRT_SEL, val);
+		break;
+
+	case U2P_EYE_TERM:
+		mtk_phy_update_field(com + U3P_USBPHYACR1, PA1_RG_TERM_SEL, val);
+		break;
+
+	case U2P_EFUSE_EN:
+		if (u2_banks->misc)
+			mtk_phy_update_field(u2_banks->misc + U3P_MISC_REG1,
+					     MR1_EFUSE_AUTO_LOAD_DIS, !!val);
+		break;
+
+	case U2P_EFUSE_INTR:
+		mtk_phy_update_field(com + U3P_USBPHYACR1, PA1_RG_INTR_CAL, val);
+		break;
+
+	case U2P_DISCTH:
+		mtk_phy_update_field(com + U3P_USBPHYACR6, PA6_RG_U2_DISCTH, val);
+		break;
+
+	case U2P_PRE_EMPHASIS:
+		mtk_phy_update_field(com + U3P_USBPHYACR6, PA6_RG_U2_PRE_EMP, val);
+		break;
+
+	default:
+		break;
+	}
+
+	return count;
+}
+
+static const struct file_operations u2_phy_fops = {
+	.open = u2_phy_params_open,
+	.write = u2_phy_params_write,
+	.read = seq_read,
+	.llseek = seq_lseek,
+	.release = single_release,
+};
+
+static void u2_phy_files_create(struct mtk_phy_instance *inst)
+{
+	u32 count = ARRAY_SIZE(u2_phy_files);
+	int i;
+
+	for (i = 0; i < count; i++)
+		debugfs_create_file(u2_phy_files[i], 0644, inst->dbgfs, inst, &u2_phy_fops);
+}
+
+static int u3_phy_params_show(struct seq_file *sf, void *unused)
+{
+	struct mtk_phy_instance *inst = sf->private;
+	const char *fname = file_dentry(sf->file)->d_iname;
+	struct u3phy_banks *u3_banks = &inst->u3_banks;
+	u32 val, tmp, max;
+	int ret;
+
+	ret = match_string(u3_phy_files, ARRAY_SIZE(u3_phy_files), fname);
+	if (ret < 0)
+		return ret;
+
+	switch (ret) {
+	case U3P_EFUSE_EN:
+		tmp = readl(u3_banks->phyd + U3P_U3_PHYD_RSV);
+		val = !!(tmp & P3D_RG_EFUSE_AUTO_LOAD_DIS);
+		max = 1;
+		break;
+
+	case U3P_EFUSE_INTR:
+		tmp = readl(u3_banks->phya + U3P_U3_PHYA_REG0);
+		val = FIELD_GET(P3A_RG_IEXT_INTR, tmp);
+		max = FIELD_MAX(P3A_RG_IEXT_INTR);
+		break;
+
+	case U3P_EFUSE_TX_IMP:
+		tmp = readl(u3_banks->phyd + U3P_U3_PHYD_IMPCAL0);
+		val = FIELD_GET(P3D_RG_TX_IMPEL, tmp);
+		max = FIELD_MAX(P3D_RG_TX_IMPEL);
+		break;
+
+	case U3P_EFUSE_RX_IMP:
+		tmp = readl(u3_banks->phyd + U3P_U3_PHYD_IMPCAL1);
+		val = FIELD_GET(P3D_RG_RX_IMPEL, tmp);
+		max = FIELD_MAX(P3D_RG_RX_IMPEL);
+		break;
+
+	default:
+		seq_printf(sf, "invalid, %d\n", ret);
+		break;
+	}
+
+	seq_printf(sf, "%s : %d [0, %d]\n", fname, val, max);
+
+	return 0;
+}
+
+static int u3_phy_params_open(struct inode *inode, struct file *file)
+{
+	return single_open(file, u3_phy_params_show, inode->i_private);
+}
+
+static ssize_t u3_phy_params_write(struct file *file, const char __user *ubuf,
+				   size_t count, loff_t *ppos)
+{
+	const char *fname = file_dentry(file)->d_iname;
+	struct seq_file *sf = file->private_data;
+	struct mtk_phy_instance *inst = sf->private;
+	struct u3phy_banks *u3_banks = &inst->u3_banks;
+	void __iomem *phyd = u3_banks->phyd;
+	ssize_t rc;
+	u32 val;
+	int ret;
+
+	rc = kstrtouint_from_user(ubuf, USER_BUF_LEN(count), 0, &val);
+	if (rc)
+		return rc;
+
+	ret = match_string(u3_phy_files, ARRAY_SIZE(u3_phy_files), fname);
+	if (ret < 0)
+		return (ssize_t)ret;
+
+	switch (ret) {
+	case U3P_EFUSE_EN:
+		mtk_phy_update_field(phyd + U3P_U3_PHYD_RSV,
+				     P3D_RG_EFUSE_AUTO_LOAD_DIS, !!val);
+		break;
+
+	case U3P_EFUSE_INTR:
+		mtk_phy_update_field(u3_banks->phya + U3P_U3_PHYA_REG0, P3A_RG_IEXT_INTR, val);
+		break;
+
+	case U3P_EFUSE_TX_IMP:
+		mtk_phy_update_field(phyd + U3P_U3_PHYD_IMPCAL0, P3D_RG_TX_IMPEL, val);
+		mtk_phy_set_bits(phyd + U3P_U3_PHYD_IMPCAL0, P3D_RG_FORCE_TX_IMPEL);
+		break;
+
+	case U3P_EFUSE_RX_IMP:
+		mtk_phy_update_field(phyd + U3P_U3_PHYD_IMPCAL1, P3D_RG_RX_IMPEL, val);
+		mtk_phy_set_bits(phyd + U3P_U3_PHYD_IMPCAL1, P3D_RG_FORCE_RX_IMPEL);
+		break;
+
+	default:
+		break;
+	}
+
+	return count;
+}
+
+static const struct file_operations u3_phy_fops = {
+	.open = u3_phy_params_open,
+	.write = u3_phy_params_write,
+	.read = seq_read,
+	.llseek = seq_lseek,
+	.release = single_release,
+};
+
+static void u3_phy_files_create(struct mtk_phy_instance *inst)
+{
+	u32 count = ARRAY_SIZE(u3_phy_files);
+	int i;
+
+	for (i = 0; i < count; i++)
+		debugfs_create_file(u3_phy_files[i], 0644, inst->dbgfs, inst, &u3_phy_fops);
+}
+
+static int tphy_type_show(struct seq_file *sf, void *unused)
+{
+	struct mtk_phy_instance *inst = sf->private;
+	const char *type;
+
+	switch (inst->type) {
+	case PHY_TYPE_USB2:
+		type = "USB2";
+		break;
+	case PHY_TYPE_USB3:
+		type = "USB3";
+		break;
+	case PHY_TYPE_PCIE:
+		type = "PCIe";
+		break;
+	case PHY_TYPE_SGMII:
+		type = "SGMII";
+		break;
+	case PHY_TYPE_SATA:
+		type = "SATA";
+		break;
+	default:
+		type = "";
+	}
+
+	seq_printf(sf, "%s\n", type);
+
+	return 0;
+}
+
+DEFINE_SHOW_ATTRIBUTE(tphy_type);
+
+static void tphy_debufs_init(struct mtk_tphy *tphy, struct mtk_phy_instance *inst)
+{
+	char name[16];
+
+	snprintf(name, sizeof(name) - 1, "phy.%d", inst->index);
+	inst->dbgfs = debugfs_create_dir(name, tphy->dbgfs_root);
+
+	debugfs_create_file("type", 0444, inst->dbgfs, inst, &tphy_type_fops);
+
+	switch (inst->type) {
+	case PHY_TYPE_USB2:
+		u2_phy_files_create(inst);
+		break;
+	case PHY_TYPE_USB3:
+	case PHY_TYPE_PCIE:
+		u3_phy_files_create(inst);
+		break;
+	default:
+		break;
+	}
+}
+
+static void tphy_debufs_exit(struct mtk_phy_instance *inst)
+{
+	debugfs_remove_recursive(inst->dbgfs);
+	inst->dbgfs = NULL;
+}
+
 static void hs_slew_rate_calibrate(struct mtk_tphy *tphy,
 	struct mtk_phy_instance *instance)
 {
@@ -1032,6 +1386,8 @@ static int mtk_phy_init(struct phy *phy)
 		return -EINVAL;
 	}
 
+	tphy_debufs_init(tphy, instance);
+
 	return 0;
 }
 
@@ -1068,6 +1424,8 @@ static int mtk_phy_exit(struct phy *phy)
 	struct mtk_phy_instance *instance = phy_get_drvdata(phy);
 	struct mtk_tphy *tphy = dev_get_drvdata(phy->dev.parent);
 
+	tphy_debufs_exit(instance);
+
 	if (instance->type == PHY_TYPE_USB2)
 		u2_phy_instance_exit(tphy, instance);
 
@@ -1295,15 +1653,30 @@ static int mtk_tphy_probe(struct platform_device *pdev)
 	}
 
 	provider = devm_of_phy_provider_register(dev, mtk_phy_xlate);
+	if (IS_ERR(provider))
+		return dev_err_probe(dev, PTR_ERR(provider), "probe failed\n");
+
+	tphy->dbgfs_root = debugfs_create_dir(dev_name(dev), phy_debug_root);
+	return 0;
 
-	return PTR_ERR_OR_ZERO(provider);
 put_child:
 	of_node_put(child_np);
 	return retval;
 }
 
+static int mtk_tphy_remove(struct platform_device *pdev)
+{
+	struct mtk_tphy *tphy;
+
+	tphy = platform_get_drvdata(pdev);
+	debugfs_remove_recursive(tphy->dbgfs_root);
+	tphy->dbgfs_root = NULL;
+	return 0;
+}
+
 static struct platform_driver mtk_tphy_driver = {
 	.probe		= mtk_tphy_probe,
+	.remove		= mtk_tphy_remove,
 	.driver		= {
 		.name	= "mtk-tphy",
 		.of_match_table = mtk_tphy_id_table,
-- 
2.18.0

Re: [PATCH 2/2] phy: mediatek: tphy: add debugfs files

[AngeloGioacchino Del Regno]

Il 28/09/22 11:30, Chunfeng Yun ha scritto:
> These debugfs files are mainly used to make eye diagram test easier,
> especially helpful to do HQA test for a new IC without efuse enabled.
> 
> Signed-off-by: Chunfeng Yun <chunfeng.yun@mediatek.com>

Even though this won't be interesting for the vast majority of the people
out there (the users!), it's still nice to have it for IC testing performed
directly on upstream, as that opens new possibilities for you and ODMs/OEMs,
so I agree on getting that code upstreamed.

For that reason, I think that the best approach for this one would be to
enclose it in a configuration option like CONFIG_PHY_MTK_TPHY_DEBUGFS or
CONFIG_PHY_MTK_TPHY_DEBUG, so that this very low level debugging code
doesn't end up in end-user builds, as that may, in some cases, be even
dangerous.

Regards,
Angelo

Re: [PATCH 2/2] phy: mediatek: tphy: add debugfs files

[Chunfeng Yun]

On Wed, 2022-09-28 at 15:35 +0200, AngeloGioacchino Del Regno wrote:
> Il 28/09/22 11:30, Chunfeng Yun ha scritto:
> > These debugfs files are mainly used to make eye diagram test
> > easier,
> > especially helpful to do HQA test for a new IC without efuse
> > enabled.
> > 
> > Signed-off-by: Chunfeng Yun <chunfeng.yun@mediatek.com>
> 
> Even though this won't be interesting for the vast majority of the
> people
> out there (the users!), it's still nice to have it for IC testing
> performed
> directly on upstream, as that opens new possibilities for you and
> ODMs/OEMs,
> so I agree on getting that code upstreamed.
> 
> For that reason, I think that the best approach for this one would be
> to
> enclose it in a configuration option like CONFIG_PHY_MTK_TPHY_DEBUGFS
> or
> CONFIG_PHY_MTK_TPHY_DEBUG, so that this very low level debugging code
> doesn't end up in end-user builds, as that may, in some cases, be
> even
> dangerous.
Yes, It seems better, I'll modify it, thanks a lot

> 
> Regards,
> Angelo
>