openwrt/target/linux/ramips/patches-5.4/0123-mips-ralink-manage-low-reset-lines.patch

From 3f9ef7785a9cd69cb75f5e2ea4ca79a24752e496 Mon Sep 17 00:00:00 2001
From: Sander Vanheule <sander@svanheule.net>
Date: Wed, 3 Feb 2021 10:21:41 +0100
Subject: MIPS: ralink: manage low reset lines

Reset lines with indices smaller than 8 are currently considered invalid
by the rt2880-reset reset controller.

The MT7621 SoC uses a number of these low reset lines. The DTS defines
reset lines "hsdma", "fe", and "mcm" with respective values 5, 6, and 2.
As a result of the above restriction, these resets cannot be asserted or
de-asserted by the reset controller. In cases where the bootloader does
not de-assert these lines, this results in e.g. the MT7621's internal
switch staying in reset.

Change the reset controller to only ignore the system reset, so all
reset lines with index greater than 0 are considered valid.

Signed-off-by: Sander Vanheule <sander@svanheule.net>
Acked-by: John Crispin <john@phrozen.org>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
---
 arch/mips/ralink/reset.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/arch/mips/ralink/reset.c b/arch/mips/ralink/reset.c
index 8126f12604071..274d33078c5eb 100644
--- a/arch/mips/ralink/reset.c
+++ b/arch/mips/ralink/reset.c
@@ -27,7 +27,7 @@ static int ralink_assert_device(struct reset_controller_dev *rcdev,
 {
 	u32 val;
 
-	if (id < 8)
+	if (id == 0)
 		return -1;
 
 	val = rt_sysc_r32(SYSC_REG_RESET_CTRL);
@@ -42,7 +42,7 @@ static int ralink_deassert_device(struct reset_controller_dev *rcdev,
 {
 	u32 val;
 
-	if (id < 8)
+	if (id == 0)
 		return -1;
 
 	val = rt_sysc_r32(SYSC_REG_RESET_CTRL);