From a622310f7f0185da02e42cdb06475f533efaae60 Mon Sep 17 00:00:00 2001
From: "H. Nikolaus Schaller" <hns@goldelico.com>
Date: Fri, 13 Jan 2023 22:11:51 +0100
Subject: [PATCH] ARM: dts: gta04: fix excess dma channel usage
Git-commit: a622310f7f0185da02e42cdb06475f533efaae60
Patch-mainline: v6.4-rc1
References: git-fixes

OMAP processors support 32 channels but there is no check or
inspect this except booting a device and looking at dmesg reports
of not available channels.

Recently some more subsystems with DMA (aes1+2) were added filling
the list of dma channels beyond the limit of 32 (even if other
parameters indicate 96 or 128 channels). This leads to random
subsystem failures i(e.g. mcbsp for audio) after boot or boot
messages that DMA can not be initialized.

Another symptom is that

/sys/kernel/debug/dmaengine/summary

has 32 entries and does not show all required channels.

Fix by disabling unused (on the GTA04 hardware) mcspi1...4.
Each SPI channel allocates 4 DMA channels rapidly filling
the available ones.

Disabling unused SPI modules on the OMAP3 SoC may also save
some energy (has not been checked).

Fixes: c312f066314e ("ARM: dts: omap3: Migrate AES from hwmods to sysc-omap2")
Signed-off-by: H. Nikolaus Schaller <hns@goldelico.com>
[re-enabled aes2, improved commit subject line]

Signed-off-by: Andreas Kemnade <andreas@kemnade.info>
Message-id: <20230113211151.2314874-1-andreas@kemnade.info>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Acked-by: Takashi Iwai <tiwai@suse.de>

---
 arch/arm/boot/dts/omap3-gta04.dtsi | 16 ++++++++++++++++
 1 file changed, 16 insertions(+)

diff --git a/arch/arm/boot/dts/omap3-gta04.dtsi b/arch/arm/boot/dts/omap3-gta04.dtsi
index 87e0ab1bbe95..e0be0fb23f80 100644
--- a/arch/arm/boot/dts/omap3-gta04.dtsi
+++ b/arch/arm/boot/dts/omap3-gta04.dtsi
@@ -612,6 +612,22 @@ &i2c3 {
 	clock-frequency = <100000>;
 };
 
+&mcspi1 {
+	status = "disabled";
+};
+
+&mcspi2 {
+	status = "disabled";
+};
+
+&mcspi3 {
+	status = "disabled";
+};
+
+&mcspi4 {
+	status = "disabled";
+};
+
 &usb_otg_hs {
 	interface-type = <0>;
 	usb-phy = <&usb2_phy>;
-- 
2.35.3