xtensa/esp32s3: SPI slave driver

arch/xtensa/src/esp32s3/Kconfig

@@ -301,12 +301,14 @@ config ESP32S3_SPI2
 	default n
 	select ESP32S3_SPI
 	select SPI
+	select ESP32S3_GPIO_IRQ if SPI_SLAVE
 
 config ESP32S3_SPI3
 	bool "SPI 3"
 	default n
 	select ESP32S3_SPI
 	select SPI
+	select ESP32S3_GPIO_IRQ if SPI_SLAVE
 
 config ESP32S3_DMA
 	bool "General DMA (GDMA)"
@@ -596,6 +598,11 @@ config ESP32S3_SPI_UDCS
 	---help---
 		Use user-defined CS.
 
+config ESP32S3_SPI_SLAVE_BUFSIZE
+	int "SPI slave buffer size"
+	default 2048
+	depends on SPI_SLAVE
+
 if ESP32S3_SPI2
 
 config ESP32S3_SPI2_DMA
@@ -645,6 +652,13 @@ endif # ESP32S3_SPI2
 
 if ESP32S3_SPI3
 
+config ESP32S3_SPI3_DMA
+	bool "SPI3 use GDMA"
+	default n
+	depends on ESP32S3_DMA
+	---help---
+		Enable support for transfers using the GDMA engine.
+
 config ESP32S3_SPI3_CSPIN
 	int "SPI3 CS Pin"
 	default 10

arch/xtensa/src/esp32s3/Make.defs

@@ -107,6 +107,9 @@ endif
 
 ifeq ($(CONFIG_ESP32S3_SPI),y)
 CHIP_CSRCS += esp32s3_spi.c
+ifeq ($(CONFIG_SPI_SLAVE),y)
+CHIP_CSRCS += esp32s3_spi_slave.c
+endif
 endif
 
 ifeq ($(CONFIG_ESP32S3_SPIFLASH),y)

arch/xtensa/src/esp32s3/esp32s3_dma.c

@@ -66,6 +66,7 @@
 
 static bool    g_dma_chan_used[ESP32S3_DMA_CHAN_MAX];
 static mutex_t g_dma_lock = NXMUTEX_INITIALIZER;
+static int g_dma_ref;
 
 /****************************************************************************
  * Public Functions
@@ -368,9 +369,18 @@ void esp32s3_dma_wait_idle(int chan, bool tx)
 
 void esp32s3_dma_init(void)
 {
-  modifyreg32(SYSTEM_PERIP_CLK_EN1_REG, 0, SYSTEM_DMA_CLK_EN_M);
-  modifyreg32(SYSTEM_PERIP_RST_EN1_REG, SYSTEM_DMA_RST_M, 0);
+  nxmutex_lock(&g_dma_lock);
 
-  modifyreg32(DMA_MISC_CONF_REG, 0, DMA_CLK_EN_M);
+  if (!g_dma_ref)
+    {
+      modifyreg32(SYSTEM_PERIP_CLK_EN1_REG, 0, SYSTEM_DMA_CLK_EN_M);
+      modifyreg32(SYSTEM_PERIP_RST_EN1_REG, SYSTEM_DMA_RST_M, 0);
+
+      modifyreg32(DMA_MISC_CONF_REG, 0, DMA_CLK_EN_M);
+    }
+
+  g_dma_ref++;
+
+  nxmutex_unlock(&g_dma_lock);
 }
 

arch/xtensa/src/esp32s3/esp32s3_spi.h

@@ -46,6 +46,10 @@ extern "C"
 
 #include <nuttx/spi/spi.h>
 
+#ifdef CONFIG_SPI_SLAVE
+#  include <nuttx/spi/slave.h>
+#endif
+
 #ifdef CONFIG_ESP32S3_SPI2
 #  define ESP32S3_SPI2 2
 #endif
@@ -139,6 +143,39 @@ int esp32s3_spi3_cmddata(struct spi_dev_s *dev,
 
 int esp32s3_spibus_uninitialize(struct spi_dev_s *dev);
 
+/****************************************************************************
+ * Name: esp32s3_spislave_ctrlr_initialize
+ *
+ * Description:
+ *   Initialize the selected SPI Slave bus.
+ *
+ * Input Parameters:
+ *   port - Port number (for hardware that has multiple SPI Slave interfaces)
+ *
+ * Returned Value:
+ *   Valid SPI Slave controller structure reference on success;
+ *   NULL on failure.
+ *
+ ****************************************************************************/
+
+struct spi_slave_ctrlr_s *esp32s3_spislave_ctrlr_initialize(int port);
+
+/****************************************************************************
+ * Name: esp32s3_spislave_ctrlr_uninitialize
+ *
+ * Description:
+ *   Uninitialize an SPI Slave bus.
+ *
+ * Input Parameters:
+ *   ctrlr - SPI Slave controller interface instance
+ *
+ * Returned Value:
+ *   Zero (OK) is returned on success. Otherwise -1 (ERROR).
+ *
+ ****************************************************************************/
+
+int esp32s3_spislave_ctrlr_uninitialize(struct spi_slave_ctrlr_s *ctrlr);
+
 #endif /* CONFIG_ESP32S3_SPI */
 
 #ifdef __cplusplus