soc: xtensa: esp32s3: add support for SPIRAM

Add support for external PSRAM for esp32s3.

Signed-off-by: Lucas Tamborrino <lucas.tamborrino@espressif.com>

soc/xtensa/espressif_esp32/common/Kconfig.soc

@@ -40,6 +40,15 @@ config ESP_HEAP_SEARCH_ALL_REGIONS
 menu "SPI RAM config"
 	depends on ESP_SPIRAM
 
+choice SPIRAM_MODE
+	prompt "Mode (QUAD/OCT) of SPI RAM chip in use"
+	default SPIRAM_MODE_QUAD
+
+config SPIRAM_MODE_QUAD
+	bool "Quad Mode PSRAM"
+
+endchoice # SPIRAM_MODE
+
 choice SPIRAM_TYPE
 	prompt "Type of SPI RAM chip in use"
 	depends on ESP_SPIRAM
@@ -98,6 +107,10 @@ config SPIRAM_SPEED_80M
 	depends on ESPTOOLPY_FLASHFREQ_80M
 	bool "80MHz clock speed"
 
+config SPIRAM_SPEED_120M
+	depends on SPIRAM_MODE_QUAD && SOC_SERIES_ESP32S3
+	bool "120MHz clock speed"
+
 endchoice # SPIRAM_SPEED
 
 menu "PSRAM clock and cs IO for ESP32-DOWD"

soc/xtensa/espressif_esp32/esp32s3/Kconfig.soc

@@ -293,4 +293,23 @@ config MAC_BB_PD
 
 endmenu  # Cache config
 
+menu "PSRAM Clock and CS IO for ESP32S3"
+	depends on ESP_SPIRAM
+
+config DEFAULT_PSRAM_CLK_IO
+	int "PSRAM CLK IO number"
+	range 0 33
+	default 30
+	help
+	  The PSRAM Clock IO can be any unused GPIO, please refer to your hardware design.
+
+config DEFAULT_PSRAM_CS_IO
+	int "PSRAM CS IO number"
+	range 0 33
+	default 26
+	help
+	  The PSRAM CS IO can be any unused GPIO, please refer to your hardware design.
+
+endmenu # PSRAM clock and cs IO for ESP32S3
+
 endif # SOC_SERIES_ESP32S3

soc/xtensa/espressif_esp32/esp32s3/default.ld

@@ -39,6 +39,8 @@
 #define RAMABLE_REGION dram0_0_seg
 #define ROMABLE_REGION ROM
 
+#define EXT_RAM_ORG (0x3E000000 - CONFIG_ESP_SPIRAM_SIZE)
+
 #ifdef CONFIG_FLASH_SIZE
 #define FLASH_SIZE CONFIG_FLASH_SIZE
 #else
@@ -70,7 +72,13 @@ MEMORY
    * Hence, an offset of 0x40 is added to DROM segment origin.
    */
   drom0_0_seg(R): org = 0x3C000040, len = FLASH_SIZE - 0x40
-
+  /**
+   * `extern_ram_seg` and `drom0_0_seg` share the same bus and the address region.
+   * so we allocate `extern_ram_seg` at the end of the address region.
+   */
+#if defined(CONFIG_ESP_SPIRAM)
+  ext_ram_seg(RWX): org = EXT_RAM_ORG, len = CONFIG_ESP_SPIRAM_SIZE
+#endif
   /* RTC fast memory (executable). Persists over deep sleep.
    */
   rtc_iram_seg(RWX): org = 0x600fe000, len = 0x2000
@@ -219,6 +227,17 @@ SECTIONS
     _image_rodata_end = ABSOLUTE(.);
   } GROUP_DATA_LINK_IN(RODATA_REGION, ROMABLE_REGION)
 
+#if defined(CONFIG_ESP_SPIRAM)
+  /* This section holds .ext_ram.bss data, and will be put in PSRAM */
+  .ext_ram.bss (NOLOAD) :
+  {
+    _ext_ram_bss_start = ABSOLUTE(.);
+    *(.ext_ram.bss*)
+    . = ALIGN(4);
+    _ext_ram_bss_end = ABSOLUTE(.);
+  } > ext_ram_seg
+#endif
+
   /* Send .iram0 code to iram */
   .iram0.vectors : ALIGN(4)
   {
@@ -272,6 +291,9 @@ SECTIONS
     *libsoc.a:rtc_*.*(.literal .text .literal.* .text.*)
     *libsoc.a:cpu_util.*(.literal .text .literal.* .text.*)
     *libgcc.a:lib2funcs.*(.literal .text .literal.* .text.*)
+    *libzephyr.a:spiram*.*(.literal .text .literal.* .text.*)
+    *libzephyr.a:spi_timing*.*(.literal .text .literal.* .text.*)
+    *libzephyr.a:spi_flash*.*(.literal .text .literal.* .text.*)
     *libdrivers__flash.a:flash_esp32.*(.literal .text .literal.* .text.*)
     *libzephyr.a:windowspill_asm.*(.literal .text .literal.* .text.*)
     *libzephyr.a:log_noos.*(.literal .text .literal.* .text.*)
@@ -642,3 +664,8 @@ SECTIONS
 
 ASSERT(((_iram_end - ORIGIN(iram0_0_seg)) <= LENGTH(iram0_0_seg)),
           "IRAM0 segment data does not fit.")
+
+#if defined(CONFIG_ESP_SPIRAM)
+ASSERT(((ORIGIN(ext_ram_seg)) > _image_rodata_end),
+          "External RAM segment does not fit.")
+#endif

soc/xtensa/espressif_esp32/esp32s3/soc.c

@@ -34,11 +34,18 @@
 #include "esp_app_format.h"
 #include "esp_clk_internal.h"
 
+#include "esp32s3/spiram.h"
+
 #ifdef CONFIG_MCUBOOT
 #include "bootloader_init.h"
 #endif /* CONFIG_MCUBOOT */
 #include <zephyr/sys/printk.h>
 
+#if CONFIG_ESP_SPIRAM
+extern int _ext_ram_bss_start;
+extern int _ext_ram_bss_end;
+#endif
+
 extern void z_cstart(void);
 
 #ifndef CONFIG_MCUBOOT
@@ -104,6 +111,30 @@ void IRAM_ATTR __esp_platform_start(void)
 	/* Apply SoC patches */
 	esp_errata();
 
+#if CONFIG_ESP_SPIRAM
+	esp_err_t err = esp_spiram_init();
+
+	if (err != ESP_OK) {
+		printk("Failed to Initialize external RAM, aborting.\n");
+		abort();
+	}
+
+	esp_spiram_init_cache();
+	if (esp_spiram_get_size() < CONFIG_ESP_SPIRAM_SIZE) {
+		printk("External RAM size is less than configured, aborting.\n");
+		abort();
+	}
+
+	if (!esp_spiram_test()) {
+		printk("External RAM failed memory test!\n");
+		abort();
+	}
+
+	memset(&_ext_ram_bss_start, 0,
+	       (&_ext_ram_bss_end - &_ext_ram_bss_start) * sizeof(_ext_ram_bss_start));
+
+#endif /* CONFIG_ESP_SPIRAM */
+
 	/* ESP-IDF/MCUboot 2nd stage bootloader enables RTC WDT to check on startup sequence
 	 * related issues in application. Hence disable that as we are about to start
 	 * Zephyr environment.