kernel: 5.10: backport qca8k stability improvements

This is a backport of Ansuel Smith's "Multiple improvement to qca8k stability"
series. The QCA8337 switch is available on multiple platforms including
ipq806x, ath79 and bcm53xx.

Signed-off-by: Ansuel Smith <ansuelsmth@gmail.com>
Signed-off-by: Matthew Hagan <mnhagan88@gmail.com>

target/linux/generic/backport-5.10/785-v5.14-01-net-dsa-qca8k-change-simple-print-to-dev-variant.patch

@@ -0,0 +1,35 @@
+From 5d9e068402dcf7354cc8ee66c2152845306d2ccb Mon Sep 17 00:00:00 2001
+From: Ansuel Smith <ansuelsmth@gmail.com>
+Date: Fri, 14 May 2021 22:59:51 +0200
+Subject: [PATCH] net: dsa: qca8k: change simple print to dev variant
+
+Change pr_err and pr_warn to dev variant.
+
+Signed-off-by: Ansuel Smith <ansuelsmth@gmail.com>
+Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
+Reviewed-by: Andrew Lunn <andrew@lunn.ch>
+Signed-off-by: David S. Miller <davem@davemloft.net>
+---
+ drivers/net/dsa/qca8k.c | 4 ++--
+ 1 file changed, 2 insertions(+), 2 deletions(-)
+
+--- a/drivers/net/dsa/qca8k.c
++++ b/drivers/net/dsa/qca8k.c
+@@ -701,7 +701,7 @@ qca8k_setup(struct dsa_switch *ds)
+
+ 	/* Make sure that port 0 is the cpu port */
+ 	if (!dsa_is_cpu_port(ds, 0)) {
+-		pr_err("port 0 is not the CPU port\n");
++		dev_err(priv->dev, "port 0 is not the CPU port");
+ 		return -EINVAL;
+ 	}
+
+@@ -711,7 +711,7 @@ qca8k_setup(struct dsa_switch *ds)
+ 	priv->regmap = devm_regmap_init(ds->dev, NULL, priv,
+ 					&qca8k_regmap_config);
+ 	if (IS_ERR(priv->regmap))
+-		pr_warn("regmap initialization failed");
++		dev_warn(priv->dev, "regmap initialization failed");
+
+ 	ret = qca8k_setup_mdio_bus(priv);
+ 	if (ret)

target/linux/generic/backport-5.10/785-v5.14-02-net-dsa-qca8k-use-iopoll-macro-for-qca8k_busy_wait.patch

@@ -0,0 +1,61 @@
+From 2ad255f2faaffb3af786031fba2e7955454b558a Mon Sep 17 00:00:00 2001
+From: Ansuel Smith <ansuelsmth@gmail.com>
+Date: Fri, 14 May 2021 22:59:52 +0200
+Subject: [PATCH] net: dsa: qca8k: use iopoll macro for qca8k_busy_wait
+
+Use iopoll macro instead of while loop.
+
+Signed-off-by: Ansuel Smith <ansuelsmth@gmail.com>
+Reviewed-by: Andrew Lunn <andrew@lunn.ch>
+Signed-off-by: David S. Miller <davem@davemloft.net>
+---
+ drivers/net/dsa/qca8k.c | 23 +++++++++++------------
+ drivers/net/dsa/qca8k.h |  2 ++
+ 2 files changed, 13 insertions(+), 12 deletions(-)
+
+--- a/drivers/net/dsa/qca8k.c
++++ b/drivers/net/dsa/qca8k.c
+@@ -262,21 +262,20 @@ static struct regmap_config qca8k_regmap
+ static int
+ qca8k_busy_wait(struct qca8k_priv *priv, u32 reg, u32 mask)
+ {
+-	unsigned long timeout;
++	u32 val;
++	int ret;
+
+-	timeout = jiffies + msecs_to_jiffies(20);
++	ret = read_poll_timeout(qca8k_read, val, !(val & mask),
++				0, QCA8K_BUSY_WAIT_TIMEOUT * USEC_PER_MSEC, false,
++				priv, reg);
+
+-	/* loop until the busy flag has cleared */
+-	do {
+-		u32 val = qca8k_read(priv, reg);
+-		int busy = val & mask;
++	/* Check if qca8k_read has failed for a different reason
++	 * before returning -ETIMEDOUT
++	 */
++	if (ret < 0 && val < 0)
++		return val;
+
+-		if (!busy)
+-			break;
+-		cond_resched();
+-	} while (!time_after_eq(jiffies, timeout));
+-
+-	return time_after_eq(jiffies, timeout);
++	return ret;
+ }
+
+ static void
+--- a/drivers/net/dsa/qca8k.h
++++ b/drivers/net/dsa/qca8k.h
+@@ -18,6 +18,8 @@
+ #define PHY_ID_QCA8337					0x004dd036
+ #define QCA8K_ID_QCA8337				0x13
+
++#define QCA8K_BUSY_WAIT_TIMEOUT				20
++
+ #define QCA8K_NUM_FDB_RECORDS				2048
+
+ #define QCA8K_CPU_PORT					0

target/linux/generic/backport-5.10/785-v5.14-03-net-dsa-qca8k-improve-qca8k-read-write-rmw-bus-acces.patch

@@ -0,0 +1,86 @@
+From 504bf65931824eda83494e5b5d75686e27ace03e Mon Sep 17 00:00:00 2001
+From: Ansuel Smith <ansuelsmth@gmail.com>
+Date: Fri, 14 May 2021 22:59:53 +0200
+Subject: [PATCH] net: dsa: qca8k: improve qca8k read/write/rmw bus access
+
+Put bus in local variable to improve faster access to the mdio bus.
+
+Signed-off-by: Ansuel Smith <ansuelsmth@gmail.com>
+Reviewed-by: Andrew Lunn <andrew@lunn.ch>
+Signed-off-by: David S. Miller <davem@davemloft.net>
+---
+ drivers/net/dsa/qca8k.c | 29 ++++++++++++++++-------------
+ 1 file changed, 16 insertions(+), 13 deletions(-)
+
+--- a/drivers/net/dsa/qca8k.c
++++ b/drivers/net/dsa/qca8k.c
+@@ -142,17 +142,18 @@ qca8k_set_page(struct mii_bus *bus, u16
+ static u32
+ qca8k_read(struct qca8k_priv *priv, u32 reg)
+ {
++	struct mii_bus *bus = priv->bus;
+ 	u16 r1, r2, page;
+ 	u32 val;
+
+ 	qca8k_split_addr(reg, &r1, &r2, &page);
+
+-	mutex_lock_nested(&priv->bus->mdio_lock, MDIO_MUTEX_NESTED);
++	mutex_lock_nested(&bus->mdio_lock, MDIO_MUTEX_NESTED);
+
+-	qca8k_set_page(priv->bus, page);
+-	val = qca8k_mii_read32(priv->bus, 0x10 | r2, r1);
++	qca8k_set_page(bus, page);
++	val = qca8k_mii_read32(bus, 0x10 | r2, r1);
+
+-	mutex_unlock(&priv->bus->mdio_lock);
++	mutex_unlock(&bus->mdio_lock);
+
+ 	return val;
+ }
+@@ -160,35 +161,37 @@ qca8k_read(struct qca8k_priv *priv, u32
+ static void
+ qca8k_write(struct qca8k_priv *priv, u32 reg, u32 val)
+ {
++	struct mii_bus *bus = priv->bus;
+ 	u16 r1, r2, page;
+
+ 	qca8k_split_addr(reg, &r1, &r2, &page);
+
+-	mutex_lock_nested(&priv->bus->mdio_lock, MDIO_MUTEX_NESTED);
++	mutex_lock_nested(&bus->mdio_lock, MDIO_MUTEX_NESTED);
+
+-	qca8k_set_page(priv->bus, page);
+-	qca8k_mii_write32(priv->bus, 0x10 | r2, r1, val);
++	qca8k_set_page(bus, page);
++	qca8k_mii_write32(bus, 0x10 | r2, r1, val);
+
+-	mutex_unlock(&priv->bus->mdio_lock);
++	mutex_unlock(&bus->mdio_lock);
+ }
+
+ static u32
+ qca8k_rmw(struct qca8k_priv *priv, u32 reg, u32 mask, u32 val)
+ {
++	struct mii_bus *bus = priv->bus;
+ 	u16 r1, r2, page;
+ 	u32 ret;
+
+ 	qca8k_split_addr(reg, &r1, &r2, &page);
+
+-	mutex_lock_nested(&priv->bus->mdio_lock, MDIO_MUTEX_NESTED);
++	mutex_lock_nested(&bus->mdio_lock, MDIO_MUTEX_NESTED);
+
+-	qca8k_set_page(priv->bus, page);
+-	ret = qca8k_mii_read32(priv->bus, 0x10 | r2, r1);
++	qca8k_set_page(bus, page);
++	ret = qca8k_mii_read32(bus, 0x10 | r2, r1);
+ 	ret &= ~mask;
+ 	ret |= val;
+-	qca8k_mii_write32(priv->bus, 0x10 | r2, r1, ret);
++	qca8k_mii_write32(bus, 0x10 | r2, r1, ret);
+
+-	mutex_unlock(&priv->bus->mdio_lock);
++	mutex_unlock(&bus->mdio_lock);
+
+ 	return ret;
+ }

target/linux/generic/backport-5.10/785-v5.14-04-net-dsa-qca8k-handle-qca8k_set_page-errors.patch

@@ -0,0 +1,101 @@
+From ba5707ec58cfb6853dff41c2aae72deb6a03d389 Mon Sep 17 00:00:00 2001
+From: Ansuel Smith <ansuelsmth@gmail.com>
+Date: Fri, 14 May 2021 22:59:54 +0200
+Subject: [PATCH] net: dsa: qca8k: handle qca8k_set_page errors
+
+With a remote possibility, the set_page function can fail. Since this is
+a critical part of the write/read qca8k regs, propagate the error and
+terminate any read/write operation.
+
+Signed-off-by: Ansuel Smith <ansuelsmth@gmail.com>
+Reviewed-by: Andrew Lunn <andrew@lunn.ch>
+Signed-off-by: David S. Miller <davem@davemloft.net>
+---
+ drivers/net/dsa/qca8k.c | 33 ++++++++++++++++++++++++++-------
+ 1 file changed, 26 insertions(+), 7 deletions(-)
+
+--- a/drivers/net/dsa/qca8k.c
++++ b/drivers/net/dsa/qca8k.c
+@@ -127,16 +127,23 @@ qca8k_mii_write32(struct mii_bus *bus, i
+ 				    "failed to write qca8k 32bit register\n");
+ }
+
+-static void
++static int
+ qca8k_set_page(struct mii_bus *bus, u16 page)
+ {
++	int ret;
++
+ 	if (page == qca8k_current_page)
+-		return;
++		return 0;
+
+-	if (bus->write(bus, 0x18, 0, page) < 0)
++	ret = bus->write(bus, 0x18, 0, page);
++	if (ret < 0) {
+ 		dev_err_ratelimited(&bus->dev,
+ 				    "failed to set qca8k page\n");
++		return ret;
++	}
++
+ 	qca8k_current_page = page;
++	return 0;
+ }
+
+ static u32
+@@ -150,11 +157,14 @@ qca8k_read(struct qca8k_priv *priv, u32
+
+ 	mutex_lock_nested(&bus->mdio_lock, MDIO_MUTEX_NESTED);
+
+-	qca8k_set_page(bus, page);
++	val = qca8k_set_page(bus, page);
++	if (val < 0)
++		goto exit;
++
+ 	val = qca8k_mii_read32(bus, 0x10 | r2, r1);
+
++exit:
+ 	mutex_unlock(&bus->mdio_lock);
+-
+ 	return val;
+ }
+
+@@ -163,14 +173,19 @@ qca8k_write(struct qca8k_priv *priv, u32
+ {
+ 	struct mii_bus *bus = priv->bus;
+ 	u16 r1, r2, page;
++	int ret;
+
+ 	qca8k_split_addr(reg, &r1, &r2, &page);
+
+ 	mutex_lock_nested(&bus->mdio_lock, MDIO_MUTEX_NESTED);
+
+-	qca8k_set_page(bus, page);
++	ret = qca8k_set_page(bus, page);
++	if (ret < 0)
++		goto exit;
++
+ 	qca8k_mii_write32(bus, 0x10 | r2, r1, val);
+
++exit:
+ 	mutex_unlock(&bus->mdio_lock);
+ }
+
+@@ -185,12 +200,16 @@ qca8k_rmw(struct qca8k_priv *priv, u32 r
+
+ 	mutex_lock_nested(&bus->mdio_lock, MDIO_MUTEX_NESTED);
+
+-	qca8k_set_page(bus, page);
++	ret = qca8k_set_page(bus, page);
++	if (ret < 0)
++		goto exit;
++
+ 	ret = qca8k_mii_read32(bus, 0x10 | r2, r1);
+ 	ret &= ~mask;
+ 	ret |= val;
+ 	qca8k_mii_write32(bus, 0x10 | r2, r1, ret);
+
++exit:
+ 	mutex_unlock(&bus->mdio_lock);
+
+ 	return ret;