From a29ebef6cec2cda75b1b44b30f56667dbd68bd96 Mon Sep 17 00:00:00 2001
From: Lucas Tamborrino <lucas.tamborrino@espressif.com>
Date: Thu, 15 Sep 2022 11:06:32 -0300
Subject: [PATCH] drivers: spi: esp32c3: add DMA support

Add SPI DMA support for esp32c3.

Signed-off-by: Lucas Tamborrino <lucas.tamborrino@espressif.com>
---
 drivers/spi/spi_esp32_spim.c     | 18 ++++++++++++++++--
 drivers/spi/spi_esp32_spim.h     |  6 ++++++
 dts/riscv/espressif/esp32c3.dtsi |  2 ++
 3 files changed, 24 insertions(+), 2 deletions(-)

diff --git a/drivers/spi/spi_esp32_spim.c b/drivers/spi/spi_esp32_spim.c
index 4d92ab2066..fe328e47ac 100644
--- a/drivers/spi/spi_esp32_spim.c
+++ b/drivers/spi/spi_esp32_spim.c
@@ -19,6 +19,8 @@ LOG_MODULE_REGISTER(esp32_spi, CONFIG_SPI_LOG_LEVEL);
 #ifndef CONFIG_SOC_ESP32C3
 #include <zephyr/drivers/interrupt_controller/intc_esp32.h>
 #else
+#include <hal/gdma_hal.h>
+#include <hal/gdma_ll.h>
 #include <zephyr/drivers/interrupt_controller/intc_esp32c3.h>
 #endif
 #include <zephyr/drivers/clock_control.h>
@@ -150,6 +152,7 @@ static int spi_esp32_init_dma(const struct device *dev)
 {
 	const struct spi_esp32_config *cfg = dev->config;
 	struct spi_esp32_data *data = dev->data;
+	uint8_t channel_offset;
 
 	LOG_ERR("DMA");
 	if (clock_control_on(cfg->clock_dev, (clock_control_subsys_t)cfg->dma_clk_src)) {
@@ -157,6 +160,17 @@ static int spi_esp32_init_dma(const struct device *dev)
 		return -EIO;
 	}
 
+#ifdef CONFIG_SOC_ESP32C3
+	gdma_hal_init(&data->hal_gdma, 0);
+	gdma_ll_enable_clock(data->hal_gdma.dev, true);
+	gdma_ll_tx_reset_channel(data->hal_gdma.dev, cfg->dma_host);
+	gdma_ll_rx_reset_channel(data->hal_gdma.dev, cfg->dma_host);
+	gdma_ll_tx_connect_to_periph(data->hal_gdma.dev, cfg->dma_host, 0);
+	gdma_ll_rx_connect_to_periph(data->hal_gdma.dev, cfg->dma_host, 0);
+	channel_offset = 0;
+#else
+	channel_offset = 1;
+#endif /* CONFIG_SOC_ESP32C3 */
 #ifdef CONFIG_SOC_ESP32
 	/*Connect SPI and DMA*/
 	DPORT_SET_PERI_REG_BITS(DPORT_SPI_DMA_CHAN_SEL_REG, 3, cfg->dma_host + 1,
@@ -166,8 +180,8 @@ static int spi_esp32_init_dma(const struct device *dev)
 	data->hal_config.dma_in = (spi_dma_dev_t *)cfg->spi;
 	data->hal_config.dma_out = (spi_dma_dev_t *)cfg->spi;
 	data->hal_config.dma_enabled = true;
-	data->hal_config.tx_dma_chan = cfg->dma_host + 1;
-	data->hal_config.rx_dma_chan = cfg->dma_host + 1;
+	data->hal_config.tx_dma_chan = cfg->dma_host + channel_offset;
+	data->hal_config.rx_dma_chan = cfg->dma_host + channel_offset;
 	data->hal_config.dmadesc_n = 1;
 	data->hal_config.dmadesc_rx = &data->dma_desc_rx;
 	data->hal_config.dmadesc_tx = &data->dma_desc_tx;
diff --git a/drivers/spi/spi_esp32_spim.h b/drivers/spi/spi_esp32_spim.h
index 7d69ca7ed6..f6242c9e71 100644
--- a/drivers/spi/spi_esp32_spim.h
+++ b/drivers/spi/spi_esp32_spim.h
@@ -9,6 +9,9 @@
 
 #include <zephyr/drivers/pinctrl.h>
 #include <hal/spi_hal.h>
+#ifdef CONFIG_SOC_ESP32C3
+#include <hal/gdma_hal.h>
+#endif
 
 #define SPI_MASTER_FREQ_8M      (APB_CLK_FREQ/10)
 #define SPI_MASTER_FREQ_9M      (APB_CLK_FREQ/9)    /* 8.89MHz */
@@ -39,6 +42,9 @@ struct spi_esp32_data {
 	struct spi_context ctx;
 	spi_hal_context_t hal;
 	spi_hal_config_t hal_config;
+#ifdef CONFIG_SOC_ESP32C3
+	gdma_hal_context_t hal_gdma;
+#endif
 	spi_hal_timing_conf_t timing_config;
 	spi_hal_dev_config_t dev_config;
 	spi_hal_trans_config_t trans_config;
diff --git a/dts/riscv/espressif/esp32c3.dtsi b/dts/riscv/espressif/esp32c3.dtsi
index 42b830365c..fdc04f20e5 100644
--- a/dts/riscv/espressif/esp32c3.dtsi
+++ b/dts/riscv/espressif/esp32c3.dtsi
@@ -189,6 +189,8 @@
 			interrupts = <SPI2_INTR_SOURCE>;
 			interrupt-parent = <&intc>;
 			clocks = <&rtc ESP32_SPI2_MODULE>;
+			dma-clk = <ESP32_GDMA_MODULE>;
+			dma-host = <1>;
 			status = "disabled";
 		};