boards: arm: sam4s_xplained: Enable SRAM on SMC bus

This commit enables the SRAM controller is66wv51216dbll connected
to the SMC/EBI bus. Half of the memory is made available (512KB)
on chip select 0, the other part is (512KB) on chip select 1.

The SMC timings are taken from the Microchip studio example
SMC_SRAM_EXAMPLE for the sam4s_xplained board.

Signed-off-by: Pieter De Gendt <[email protected]>

Author: pdgendt

boards/arm/sam4s_xplained/doc/index.rst

@@ -55,6 +55,8 @@ features:
 +-----------+------------+-------------------------------------+
 | HWINFO    | on-chip    | Unique device serial number         |
 +-----------+------------+-------------------------------------+
+| SMC       | on-chip    | memc (PSRAM)                        |
++-----------+------------+-------------------------------------+
 
 Other hardware features are not currently supported by Zephyr.
 

boards/arm/sam4s_xplained/sam4s_xplained-pinctrl.dtsi

@@ -41,4 +41,39 @@
 				 <PA22A_USART1_TXD>;
 		};
 	};
+	smc_default: smc_default {
+		group1 {
+			pinmux = <PC18A_EBI_A0>,
+				 <PC19A_EBI_A1>,
+				 <PC20A_EBI_A2>,
+				 <PC21A_EBI_A3>,
+				 <PC22A_EBI_A4>,
+				 <PC23A_EBI_A5>,
+				 <PC24A_EBI_A6>,
+				 <PC25A_EBI_A7>,
+				 <PC26A_EBI_A8>,
+				 <PC27A_EBI_A9>,
+				 <PC28A_EBI_A10>,
+				 <PC29A_EBI_A11>,
+				 <PC30A_EBI_A12>,
+				 <PC31A_EBI_A13>,
+				 <PA18C_EBI_A14>,
+				 <PA19C_EBI_A15>,
+				 <PA20C_EBI_A16>,
+				 <PA0C_EBI_A17>,
+				 <PA1C_EBI_A18>,
+				 <PC0A_EBI_D0>,
+				 <PC1A_EBI_D1>,
+				 <PC2A_EBI_D2>,
+				 <PC3A_EBI_D3>,
+				 <PC4A_EBI_D4>,
+				 <PC5A_EBI_D5>,
+				 <PC6A_EBI_D6>,
+				 <PC7A_EBI_D7>,
+				 <PC14A_EBI_NCS0>,
+				 <PC15A_EBI_NCS1>,
+				 <PC11A_EBI_NRD>,
+				 <PC8A_EBI_NWE>;
+		};
+	};
 };

boards/arm/sam4s_xplained/sam4s_xplained.dts

@@ -28,6 +28,20 @@
 		zephyr,flash = &flash0;
 	};
 
+	sram1: sram@60000000 {
+		compatible = "zephyr,memory-region", "mmio-sram";
+		device_type = "memory";
+		reg = <0x60000000 DT_SIZE_K(512)>;
+		zephyr,memory-region = "SRAM1";
+	};
+
+	sram2: sram@61000000 {
+		compatible = "zephyr,memory-region", "mmio-sram";
+		device_type = "memory";
+		reg = <0x61000000 DT_SIZE_K(512)>;
+		zephyr,memory-region = "SRAM2";
+	};
+
 	leds {
 		compatible = "gpio-leds";
 		yellow_led_1: led_1 {
@@ -175,3 +189,29 @@ xplained4_spi: &spi0 {
 
 xplained4_serial: &uart1 {
 };
+
+&smc {
+	status = "okay";
+	pinctrl-0 = <&smc_default>;
+	pinctrl-names = "default";
+
+	is66wv51216dbll@0 {
+		reg = <0>;
+
+		atmel,smc-write-mode = "nwe";
+		atmel,smc-read-mode = "nrd";
+		atmel,smc-setup-timing = <1 1 1 1>;
+		atmel,smc-pulse-timing = <6 6 6 6>;
+		atmel,smc-cycle-timing = <7 7>;
+	};
+
+	is66wv51216dbll@1 {
+		reg = <1>;
+
+		atmel,smc-write-mode = "nwe";
+		atmel,smc-read-mode = "nrd";
+		atmel,smc-setup-timing = <1 1 1 1>;
+		atmel,smc-pulse-timing = <6 6 6 6>;
+		atmel,smc-cycle-timing = <7 7>;
+	};
+};

boards/arm/sam4s_xplained/sam4s_xplained.yaml

@@ -8,6 +8,7 @@ toolchain:
   - xtools
 supported:
   - gpio
+  - memc
   - spi
   - watchdog
   - xplained_gpio

boards/arm/sam4s_xplained/sam4s_xplained_defconfig

@@ -12,5 +12,8 @@ CONFIG_SOC_ATMEL_SAM4S_EXT_MAINCK=y
 CONFIG_GPIO=y
 CONFIG_WDT_DISABLE_AT_BOOT=y
 
+# Enable SMC SRAM
+CONFIG_MEMC=y
+
 # Enable HW stack protection
 CONFIG_HW_STACK_PROTECTION=y