patches: add patch to fix TP-Link WDR3600/4300 reboots

patches/ath79-read-back-reset-register.patch

@@ -0,0 +1,83 @@
+From a43a4fc3ac297d2dcd2623d65a45707028ebebc0 Mon Sep 17 00:00:00 2001
+From: Grische <[email protected]>
+Date: Thu, 11 Jan 2024 17:54:47 +0100
+Subject: [PATCH] ath79: read back reset register
+
+---
+ .../0016-ath79-read-back-reset-register.patch | 64 +++++++++++++++++++
+ 1 file changed, 64 insertions(+)
+ create mode 100644 patches/openwrt/0016-ath79-read-back-reset-register.patch
+
+diff --git a/patches/openwrt/0016-ath79-read-back-reset-register.patch b/patches/openwrt/0016-ath79-read-back-reset-register.patch
+new file mode 100644
+index 00000000..bd0b17a0
+--- /dev/null
++++ b/patches/openwrt/0016-ath79-read-back-reset-register.patch
+@@ -0,0 +1,64 @@
++From a08553b3b36cc309d3f112208f8451ad85d240eb Mon Sep 17 00:00:00 2001
++From: David Bauer <[email protected]>
++Date: Thu, 11 Jan 2024 13:05:39 +0100
++Subject: [PATCH] ath79: read back reset register
++
++Read back the reset register in order to flush the cache. This fixes
++spurious reboot hangs on TP-Link TL-WDR3600 and TL-WDR4300 with Zentel
++DRAM chips.
++
++This issue was fixed in the past, but switching to the reset-driver
++specific implementation removed the cache barrier which was previously
++implicitly added by reading back the register in question.
++
++Link: freifunk-gluon/gluon#2904
++Link: openwrt#13043
++Link: https://dev.archive.openwrt.org/ticket/17839
++Link: f8a7bfe1cb2c ("MIPS: ath79: fix system restart")
++
++Signed-off-by: David Bauer <[email protected]>
++(cherry picked from commit 2fe8ecd880396b5ae25fe9583aaa1d71be0b8468)
++---
++ ...reset-ath79-read-back-reset-register.patch | 33 +++++++++++++++++++
++ 1 file changed, 33 insertions(+)
++ create mode 100644 target/linux/ath79/patches-5.10/100-reset-ath79-read-back-reset-register.patch
++
++diff --git a/target/linux/ath79/patches-5.10/100-reset-ath79-read-back-reset-register.patch b/target/linux/ath79/patches-5.10/100-reset-ath79-read-back-reset-register.patch
++new file mode 100644
++index 0000000000000..8e66fa8b6e7ca
++--- /dev/null
+++++ b/target/linux/ath79/patches-5.10/100-reset-ath79-read-back-reset-register.patch
++@@ -0,0 +1,33 @@
+++From 5d25f925d3f72ceadf922f946d5422ad77fbfc20 Mon Sep 17 00:00:00 2001
+++From: David Bauer <[email protected]>
+++Date: Thu, 11 Jan 2024 13:01:18 +0100
+++Subject: [PATCH] reset: ath79: read back reset register
+++
+++Read back the reset register in order to flush the cache. This fixes
+++spurious reboot hangs on TP-Link TL-WDR3600 and TL-WDR4300 with Zentel
+++DRAM chips.
+++
+++This issue was fixed in the past, but switching to the reset-driver
+++specific implementation removed the old fix.
+++
+++Link: https://github.com/freifunk-gluon/gluon/issues/2904
+++Link: https://github.com/openwrt/openwrt/issues/13043
+++Link: https://dev.archive.openwrt.org/ticket/17839
+++Link: f8a7bfe1cb2c ("MIPS: ath79: fix system restart")
+++
+++Signed-off-by: David Bauer <[email protected]>
+++---
+++ drivers/reset/reset-ath79.c | 2 ++
+++ 1 file changed, 2 insertions(+)
+++
+++--- a/drivers/reset/reset-ath79.c
++++++ b/drivers/reset/reset-ath79.c
+++@@ -37,6 +37,8 @@ static int ath79_reset_update(struct res
+++ 	else
+++ 		val &= ~BIT(id);
+++ 	writel(val, ath79_reset->base);
++++	/* Flush cache */
++++	readl(ath79_reset->base);
+++ 	spin_unlock_irqrestore(&ath79_reset->lock, flags);
+++ 
+++ 	return 0;
+-- 
+2.34.1
+