ramips: replace mt7621s hack with upstream patch

Refresh patches.

Tested on a dual-core MT7621 device (Ubiquiti ER-X) and a single-core
MT7621 device (Netgear R6220).

This change will make future kernel upgrades easier (avoids conflicts
with upstream).

Link: https://lore.kernel.org/lkml/20210407200738.149207-1-ilya.lipnitskiy@gmail.com/
Signed-off-by: Ilya Lipnitskiy <ilya.lipnitskiy@gmail.com>
Cc: Chuanhong Guo <gch981213@gmail.com>

1 files changed, 74 insertions, 0 deletions

diff --git a/target/linux/ramips/patches-5.10/320-MIPS-add-support-for-buggy-MT7621S-core-detection.patch b/target/linux/ramips/patches-5.10/320-MIPS-add-support-for-buggy-MT7621S-core-detection.patch
new file mode 100644
index 0000000000..0eb6676414
--- /dev/null
+++ b/target/linux/ramips/patches-5.10/320-MIPS-add-support-for-buggy-MT7621S-core-detection.patch
@@ -0,0 +1,74 @@
+From 6decd1aad15f56b169217789630a0098b496de0e Mon Sep 17 00:00:00 2001
+From: Ilya Lipnitskiy <ilya.lipnitskiy@gmail.com>
+Date: Wed, 7 Apr 2021 13:07:38 -0700
+Subject: [PATCH] MIPS: add support for buggy MT7621S core detection
+
+Most MT7621 SoCs have 2 cores, which is detected and supported properly
+by CPS.
+
+Unfortunately, MT7621 SoC has a less common S variant with only one core.
+On MT7621S, GCR_CONFIG still reports 2 cores, which leads to hangs when
+starting SMP. CPULAUNCH registers can be used in that case to detect the
+absence of the second core and override the GCR_CONFIG PCORES field.
+
+Rework a long-standing OpenWrt patch to override the value of
+mips_cps_numcores on single-core MT7621 systems.
+
+Tested on a dual-core MT7621 device (Ubiquiti ER-X) and a single-core
+MT7621 device (Netgear R6220).
+
+Original 4.14 OpenWrt patch:
+Link: https://git.openwrt.org/?p=openwrt/openwrt.git;a=commitdiff;h=4cdbc90a376dd0555201c1434a2081e055e9ceb7
+Current 5.10 OpenWrt patch:
+Link: https://git.openwrt.org/?p=openwrt/openwrt.git;a=blob;f=target/linux/ramips/patches-5.10/320-mt7621-core-detect-hack.patch;h=c63f0f4c1ec742e24d8480e80553863744b58f6a;hb=10267e17299806f9885d086147878f6c492cb904
+
+Suggested-by: Felix Fietkau <nbd@nbd.name>
+Signed-off-by: Ilya Lipnitskiy <ilya.lipnitskiy@gmail.com>
+Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
+---
+ arch/mips/include/asm/mips-cps.h | 23 ++++++++++++++++++++++-
+ 1 file changed, 22 insertions(+), 1 deletion(-)
+
+--- a/arch/mips/include/asm/mips-cps.h
++++ b/arch/mips/include/asm/mips-cps.h
+@@ -10,6 +10,8 @@
+ #include <linux/io.h>
+ #include <linux/types.h>
+ 
++#include <asm/mips-boards/launch.h>
++
+ extern unsigned long __cps_access_bad_size(void)
+ 	__compiletime_error("Bad size for CPS accessor");
+ 
+@@ -165,11 +167,30 @@ static inline uint64_t mips_cps_cluster_
+  */
+ static inline unsigned int mips_cps_numcores(unsigned int cluster)
+ {
++	unsigned int ncores;
++
+ 	if (!mips_cm_present())
+ 		return 0;
+ 
+ 	/* Add one before masking to handle 0xff indicating no cores */
+-	return (mips_cps_cluster_config(cluster) + 1) & CM_GCR_CONFIG_PCORES;
++	ncores = (mips_cps_cluster_config(cluster) + 1) & CM_GCR_CONFIG_PCORES;
++
++	if (IS_ENABLED(CONFIG_SOC_MT7621)) {
++		struct cpulaunch *launch;
++
++		/*
++		 * Ralink MT7621S SoC is single core, but the GCR_CONFIG method
++		 * always reports 2 cores. Check the second core's LAUNCH_FREADY
++		 * flag to detect if the second core is missing. This method
++		 * only works before the core has been started.
++		 */
++		launch = (struct cpulaunch *)CKSEG0ADDR(CPULAUNCH);
++		launch += 2; /* MT7621 has 2 VPEs per core */
++		if (!(launch->flags & LAUNCH_FREADY))
++			ncores = 1;
++	}
++
++	return ncores;
+ }
+ 
+ /**