lantiq: kernel 4.14: Remove reboot/remove reset asserts

Backport patch accepted upstream which removes the reset asserts of the
xrx200 gphy driver on reboot/remove.

While doing a global software reset, these bits are not cleared and let
some bootloader fail to initialise the GPHYs. The bootloader don't expect
these bits to be set, as they aren't during power on.

The asserts were a workaround for a wrong syscon-reboot mask. With a mask
set which includes the GPHY resets of the first reset register, the
resets of the second reset register arn't required any more.

Signed-off-by: Mathias Kresin <dev@kresin.me>

1 files changed, 86 insertions, 0 deletions

diff --git a/target/linux/lantiq/patches-4.14/0025-MIPS-lantiq-gphy-Remove-reboot-remove-reset-asserts.patch b/target/linux/lantiq/patches-4.14/0025-MIPS-lantiq-gphy-Remove-reboot-remove-reset-asserts.patch
new file mode 100644
index 0000000000..6efa6f13d9
--- /dev/null
+++ b/target/linux/lantiq/patches-4.14/0025-MIPS-lantiq-gphy-Remove-reboot-remove-reset-asserts.patch
@@ -0,0 +1,86 @@
+From ae14aba7fc748b2da282b59a2f516a311ed1f6eb Mon Sep 17 00:00:00 2001
+From: Mathias Kresin <dev@kresin.me>
+Date: Tue, 27 Mar 2018 23:15:07 +0200
+Subject: [PATCH] MIPS: lantiq: gphy: Remove reboot/remove reset asserts
+
+While doing a global software reset, these bits are not cleared and let
+some bootloader fail to initialise the GPHYs. The bootloader don't expect
+these bits to be set, as they aren't during power on.
+
+The asserts were a workaround for a wrong syscon-reboot mask. With a mask
+set which includes the GPHY resets of the first reset register, the
+resets of the second reset register arn't required any more.
+
+Signed-off-by: Mathias Kresin <dev@kresin.me>
+---
+ drivers/soc/lantiq/gphy.c | 34 ----------------------------------
+ 1 file changed, 34 deletions(-)
+
+--- a/drivers/soc/lantiq/gphy.c
++++ b/drivers/soc/lantiq/gphy.c
+@@ -30,7 +30,6 @@ struct xway_gphy_priv {
+ 	struct clk *gphy_clk_gate;
+ 	struct reset_control *gphy_reset;
+ 	struct reset_control *gphy_reset2;
+-	struct notifier_block gphy_reboot_nb;
+ 	void __iomem *membase;
+ 	char *fw_name;
+ };
+@@ -65,24 +64,6 @@ static const struct of_device_id xway_gp
+ };
+ MODULE_DEVICE_TABLE(of, xway_gphy_match);
+ 
+-static struct xway_gphy_priv *to_xway_gphy_priv(struct notifier_block *nb)
+-{
+-	return container_of(nb, struct xway_gphy_priv, gphy_reboot_nb);
+-}
+-
+-static int xway_gphy_reboot_notify(struct notifier_block *reboot_nb,
+-				   unsigned long code, void *unused)
+-{
+-	struct xway_gphy_priv *priv = to_xway_gphy_priv(reboot_nb);
+-
+-	if (priv) {
+-		reset_control_assert(priv->gphy_reset);
+-		reset_control_assert(priv->gphy_reset2);
+-	}
+-
+-	return NOTIFY_DONE;
+-}
+-
+ static int xway_gphy_load(struct device *dev, struct xway_gphy_priv *priv,
+ 			  dma_addr_t *dev_addr)
+ {
+@@ -216,14 +197,6 @@ static int xway_gphy_probe(struct platfo
+ 	reset_control_deassert(priv->gphy_reset);
+ 	reset_control_deassert(priv->gphy_reset2);
+ 
+-	/* assert the gphy reset because it can hang after a reboot: */
+-	priv->gphy_reboot_nb.notifier_call = xway_gphy_reboot_notify;
+-	priv->gphy_reboot_nb.priority = -1;
+-
+-	ret = register_reboot_notifier(&priv->gphy_reboot_nb);
+-	if (ret)
+-		dev_warn(dev, "Failed to register reboot notifier\n");
+-
+ 	platform_set_drvdata(pdev, priv);
+ 
+ 	return ret;
+@@ -235,17 +208,10 @@ static int xway_gphy_remove(struct platf
+ 	struct xway_gphy_priv *priv = platform_get_drvdata(pdev);
+ 	int ret;
+ 
+-	reset_control_assert(priv->gphy_reset);
+-	reset_control_assert(priv->gphy_reset2);
+-
+ 	iowrite32be(0, priv->membase);
+ 
+ 	clk_disable_unprepare(priv->gphy_clk_gate);
+ 
+-	ret = unregister_reboot_notifier(&priv->gphy_reboot_nb);
+-	if (ret)
+-		dev_warn(dev, "Failed to unregister reboot notifier\n");
+-
+ 	return 0;
+ }
+