From 1a8bd48265e4eccce82fa197d48701eba16aeaa2 Mon Sep 17 00:00:00 2001 From: Jisheng Zhang Date: Wed, 19 Nov 2025 20:11:20 +0800 Subject: [PATCH 1/2] boards: st: stm32h745i_disco: m7: Fix sdram available size According to UM2488 section 6.12[1], the available SDRAM size is only 8MB by hardware design, though 128Bit SDRAM is connected. Link: https://www.st.com/resource/en/user_manual/um2488-discovery-kits-with-stm32h745xi-and-stm32h750xb-mcus-stmicroelectronics.pdf [1] Signed-off-by: Jisheng Zhang --- boards/st/stm32h745i_disco/stm32h745i_disco_stm32h745xx_m7.dts | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/boards/st/stm32h745i_disco/stm32h745i_disco_stm32h745xx_m7.dts b/boards/st/stm32h745i_disco/stm32h745i_disco_stm32h745xx_m7.dts index 66f7d4d4163f3..1a8c0a94d94e8 100644 --- a/boards/st/stm32h745i_disco/stm32h745i_disco_stm32h745xx_m7.dts +++ b/boards/st/stm32h745i_disco/stm32h745i_disco_stm32h745xx_m7.dts @@ -37,7 +37,8 @@ sdram2: sdram@d0000000 { compatible = "zephyr,memory-region", "mmio-sram"; device_type = "memory"; - reg = <0xd0000000 DT_SIZE_M(16)>; /* 128Mbit */ + /* 128Mbit, but only half is available by HW design */ + reg = <0xd0000000 DT_SIZE_M(8)>; zephyr,memory-region = "SDRAM2"; zephyr,memory-attr = ; }; From 6c6739f3c58ca5ffade597551c5069a120631e60 Mon Sep 17 00:00:00 2001 From: Jisheng Zhang Date: Thu, 20 Nov 2025 08:54:25 +0800 Subject: [PATCH 2/2] boards: st: stm32h750b-dk: Fix sdram available size According to UM2488 section 6.12[1], the available SDRAM size is only 8MB by hardware design, though 128Bit SDRAM is connected. Link: https://www.st.com/resource/en/user_manual/um2488-discovery-kits-with-stm32h745xi-and-stm32h750xb-mcus-stmicroelectronics.pdf [1] Signed-off-by: Jisheng Zhang --- boards/st/stm32h750b_dk/stm32h750b_dk-common.dtsi | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/boards/st/stm32h750b_dk/stm32h750b_dk-common.dtsi b/boards/st/stm32h750b_dk/stm32h750b_dk-common.dtsi index a6be8805690a6..2581853ec1902 100644 --- a/boards/st/stm32h750b_dk/stm32h750b_dk-common.dtsi +++ b/boards/st/stm32h750b_dk/stm32h750b_dk-common.dtsi @@ -20,7 +20,8 @@ sdram2: sdram@d0000000 { compatible = "zephyr,memory-region", "mmio-sram"; device_type = "memory"; - reg = <0xd0000000 DT_SIZE_M(16)>; /* 128Mbit */ + /* 128Mbit, but only half is available by HW design */ + reg = <0xd0000000 DT_SIZE_M(8)>; zephyr,memory-region = "SDRAM2"; zephyr,memory-attr = ; };