From: Alain Volmat <alain.volmat@foss.st.com>
Date: Tue, 6 Jan 2026 11:34:40 +0000 (+0100)
Subject: ARM: dts: stm32: enable DCMI DMA-MDMA chaining on stm32mp157c-ev1.dts
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=bb3fa3f8a4166e6fbc769e208a1932242800f8e5;p=thirdparty%2Fkernel%2Fstable.git

ARM: dts: stm32: enable DCMI DMA-MDMA chaining on stm32mp157c-ev1.dts

Enable the DMA-MDMA chaining for the dcmi (camera capture)
in order to be able to achieve higher resolution.

Signed-off-by: Alain Volmat <alain.volmat@foss.st.com>
Link: https://lore.kernel.org/r/20260106-stm32-dcmi-dma-chaining-v2-12-70688bccd80a@foss.st.com
Signed-off-by: Alexandre Torgue <alexandre.torgue@foss.st.com>
---

diff --git a/arch/arm/boot/dts/st/stm32mp157c-ev1.dts b/arch/arm/boot/dts/st/stm32mp157c-ev1.dts
index 4e46d58bf61f..99c7efd73aee 100644
--- a/arch/arm/boot/dts/st/stm32mp157c-ev1.dts
+++ b/arch/arm/boot/dts/st/stm32mp157c-ev1.dts
@@ -86,6 +86,14 @@
 	pinctrl-names = "default", "sleep";
 	pinctrl-0 = <&dcmi_pins_a>;
 	pinctrl-1 = <&dcmi_sleep_pins_a>;
+	/*
+	 * Enable DMA-MDMA chaining by adding a SRAM pool and
+	 * a MDMA channel
+	 */
+	sram = <&dcmi_pool>;
+
+	dmas = <&dmamux1 75 0x400 0x01>, <&mdma1 0 0x3 0x1200000a 0 0>;
+	dma-names = "tx", "mdma_tx";
 
 	port {
 		dcmi_0: endpoint {
@@ -302,6 +310,13 @@
 	status = "disabled";
 };
 
+&sram4 {
+	dcmi_pool: dcmi-sram@0 {
+		reg = <0x0 0x8000>;
+		pool;
+	};
+};
+
 &timers2 {
 	/* spare dmas for other usage (un-delete to enable pwm capture) */
 	/delete-property/dmas;