drivers: esp32/clock_control: support UART, I2C

- Change default CPU Clock to 240MHz
(PLL is activated)
- I2C, UART will use sysclk from clock driver
- esp32_enable_peripheral replaced by
clock_control_on

Signed-off-by: Mohamed ElShahawi <ExtremeGTX@hotmail.com>

boards/xtensa/esp32/esp32.dts

@@ -24,11 +24,11 @@
 };
 
 &cpu0 {
-	clock-frequency = <ESP32_CLK_CPU_40M>;
+	clock-frequency = <ESP32_CLK_CPU_240M>;
 };
 
 &cpu1 {
-	clock-frequency = <ESP32_CLK_CPU_40M>;
+	clock-frequency = <ESP32_CLK_CPU_240M>;
 };
 
 &uart0 {

boards/xtensa/esp32/esp32_defconfig

@@ -7,7 +7,7 @@ CONFIG_SOC_ESP32=y
 
 CONFIG_MAIN_STACK_SIZE=2048
 
-CONFIG_SYS_CLOCK_HW_CYCLES_PER_SEC=40000000
+CONFIG_SYS_CLOCK_HW_CYCLES_PER_SEC=240000000
 
 CONFIG_CONSOLE=y
 CONFIG_SERIAL=y

drivers/i2c/i2c_esp32.c

@@ -17,6 +17,7 @@
 #include <drivers/gpio.h>
 #include <drivers/gpio/gpio_esp32.h>
 #include <drivers/i2c.h>
+#include <drivers/clock_control.h>
 #include <sys/util.h>
 #include <string.h>
 
@@ -61,6 +62,7 @@ struct i2c_esp32_data {
 
 	struct k_sem fifo_sem;
 	struct k_sem transfer_sem;
+	struct device *clock_dev;
 };
 
 typedef void (*irq_connect_cb)(void);
@@ -69,6 +71,7 @@ struct i2c_esp32_config {
 	int index;
 
 	irq_connect_cb connect_irq;
+	const char *clock_name;
 
 	const struct {
 		int sda_out;
@@ -82,7 +85,7 @@ struct i2c_esp32_config {
 		int sda;
 	} pins;
 
-	const struct esp32_peripheral peripheral;
+	const clock_control_subsys_t peripheral_id;
 
 	const struct {
 		bool tx_lsb_first;
@@ -126,7 +129,7 @@ static int i2c_esp32_configure_pins(int pin, int matrix_out, int matrix_in)
 	return 0;
 }
 
-static int i2c_esp32_configure_speed(const struct i2c_esp32_config *config,
+static int i2c_esp32_configure_speed(struct device *dev,
 				     uint32_t speed)
 {
 	static const uint32_t speed_to_freq_tbl[] = {
@@ -136,6 +139,11 @@ static int i2c_esp32_configure_speed(const struct i2c_esp32_config *config,
 		[I2C_SPEED_HIGH] = 0,
 		[I2C_SPEED_ULTRA] = 0
 	};
+
+	const struct i2c_esp32_config *config = dev->config_info;
+	struct i2c_esp32_data *data = dev->driver_data;
+
+	uint32_t sys_clk_freq = 0;
 	uint32_t freq_hz = speed_to_freq_tbl[speed];
 	uint32_t period;
 
@@ -143,8 +151,13 @@ static int i2c_esp32_configure_speed(const struct i2c_esp32_config *config,
 		return -ENOTSUP;
 	}
 
-	period = (APB_CLK_FREQ / freq_hz);
+	if (clock_control_get_rate(data->clock_dev,
+				   config->peripheral_id,
+				   &sys_clk_freq)) {
+		return -EINVAL;
+	}
 
+	period = (sys_clk_freq / freq_hz);
 	period /= 2U; /* Set hold and setup times to 1/2th of period */
 
 	esp32_set_mask32(period << I2C_SCL_LOW_PERIOD_S,
@@ -192,7 +205,7 @@ static int i2c_esp32_configure(struct device *dev, uint32_t dev_config)
 		return ret;
 	}
 
-	esp32_enable_peripheral(&config->peripheral);
+	clock_control_on(data->clock_dev, config->peripheral_id);
 
 	/* MSB or LSB first is configurable for both TX and RX */
 	if (config->mode.tx_lsb_first) {
@@ -228,7 +241,7 @@ static int i2c_esp32_configure(struct device *dev, uint32_t dev_config)
 	v |= I2C_CLK_EN;
 	sys_write32(v, I2C_CTR_REG(config->index));
 
-	ret = i2c_esp32_configure_speed(config, I2C_SPEED_GET(dev_config));
+	ret = i2c_esp32_configure_speed(dev, I2C_SPEED_GET(dev_config));
 	if (ret < 0) {
 		goto out;
 	}
@@ -578,6 +591,8 @@ static void i2c_esp32_connect_irq_0(void)
 static const struct i2c_esp32_config i2c_esp32_config_0 = {
 	.index = 0,
 	.connect_irq = i2c_esp32_connect_irq_0,
+	.clock_name = DT_INST_CLOCKS_LABEL(0),
+	.peripheral_id = (clock_control_subsys_t)DT_INST_CLOCKS_CELL(0, offset),
 	.sig = {
 		.sda_out = I2CEXT0_SDA_OUT_IDX,
 		.sda_in = I2CEXT0_SDA_IN_IDX,
@@ -588,10 +603,6 @@ static const struct i2c_esp32_config i2c_esp32_config_0 = {
 		.scl = DT_INST_PROP(0, scl_pin),
 		.sda = DT_INST_PROP(0, sda_pin),
 	},
-	.peripheral = {
-		.clk = DPORT_I2C_EXT0_CLK_EN,
-		.rst = DPORT_I2C_EXT0_RST,
-	},
 	.mode = {
 		.tx_lsb_first =
 			IS_ENABLED(CONFIG_I2C_ESP32_0_TX_LSB_FIRST),
@@ -626,6 +637,8 @@ static void i2c_esp32_connect_irq_1(void)
 static const struct i2c_esp32_config i2c_esp32_config_1 = {
 	.index = 1,
 	.connect_irq = i2c_esp32_connect_irq_1,
+	.clock_name = DT_INST_CLOCKS_LABEL(1),
+	.peripheral_id = (clock_control_subsys_t)DT_INST_CLOCKS_CELL(1, offset),
 	.sig = {
 		.sda_out = I2CEXT1_SDA_OUT_IDX,
 		.sda_in = I2CEXT1_SDA_IN_IDX,
@@ -636,10 +649,6 @@ static const struct i2c_esp32_config i2c_esp32_config_1 = {
 		.scl = DT_INST_PROP(1, scl_pin),
 		.sda = DT_INST_PROP(1, sda_pin),
 	},
-	.peripheral = {
-		.clk = DPORT_I2C_EXT1_CLK_EN,
-		.rst = DPORT_I2C_EXT1_RST,
-	},
 	.mode = {
 		.tx_lsb_first =
 			IS_ENABLED(CONFIG_I2C_ESP32_1_TX_LSB_FIRST),
@@ -667,6 +676,10 @@ static int i2c_esp32_init(struct device *dev)
 	const struct i2c_esp32_config *config = dev->config_info;
 	struct i2c_esp32_data *data = dev->driver_data;
 	uint32_t bitrate_cfg = i2c_map_dt_bitrate(config->bitrate);
+	data->clock_dev = device_get_binding(config->clock_name);
+
+	__ASSERT_NO_MSG(data->clock_dev);
+
 	unsigned int key = irq_lock();
 
 	k_sem_init(&data->fifo_sem, 1, 1);

drivers/serial/uart_esp32.c

@@ -17,6 +17,7 @@
 #include <device.h>
 #include <soc.h>
 #include <drivers/uart.h>
+#include <drivers/clock_control.h>
 #include <errno.h>
 #include <sys/util.h>
 
@@ -62,6 +63,7 @@ struct uart_esp32_regs_t {
 struct uart_esp32_config {
 
 	struct uart_device_config dev_conf;
+	const char *clock_name;
 
 	const struct {
 		int tx_out;
@@ -77,7 +79,7 @@ struct uart_esp32_config {
 		int cts;
 	} pins;
 
-	const struct esp32_peripheral peripheral;
+	const clock_control_subsys_t peripheral_id;
 
 	const struct {
 		int source;
@@ -88,6 +90,7 @@ struct uart_esp32_config {
 /* driver data */
 struct uart_esp32_data {
 	struct uart_config uart_config;
+	struct device *clock_dev;
 #ifdef CONFIG_UART_INTERRUPT_DRIVEN
 	uart_irq_callback_user_data_t irq_cb;
 	void *irq_cb_data;
@@ -185,7 +188,14 @@ static int uart_esp32_config_get(struct device *dev, struct uart_config *cfg)
 
 static int uart_esp32_set_baudrate(struct device *dev, int baudrate)
 {
-	uint32_t sys_clk_freq = DEV_CFG(dev)->dev_conf.sys_clk_freq;
+	uint32_t sys_clk_freq = 0;
+
+	if (clock_control_get_rate(DEV_DATA(dev)->clock_dev,
+				   DEV_CFG(dev)->peripheral_id,
+				   &sys_clk_freq)) {
+		return -EINVAL;
+	}
+
 	uint32_t clk_div = (((sys_clk_freq) << 4) / baudrate);
 
 	while (UART_TXFIFO_COUNT(DEV_BASE(dev)->status)) {
@@ -237,7 +247,7 @@ static int uart_esp32_configure(struct device *dev,
 		      | (UART_TX_FIFO_THRESH << UART_TXFIFO_EMPTY_THRHD_S);
 
 	uart_esp32_configure_pins(dev);
-	esp32_enable_peripheral(&DEV_CFG(dev)->peripheral);
+	clock_control_on(DEV_DATA(dev)->clock_dev, DEV_CFG(dev)->peripheral_id);
 
 	/*
 	 * Reset RX Buffer by reading all received bytes
@@ -305,6 +315,12 @@ static int uart_esp32_configure(struct device *dev,
 
 static int uart_esp32_init(struct device *dev)
 {
+	struct uart_esp32_data *data = DEV_DATA(dev);
+
+	data->clock_dev = device_get_binding(DEV_CFG(dev)->clock_name);
+
+	__ASSERT_NO_MSG(data->clock_dev);
+
 	uart_esp32_configure(dev, &DEV_DATA(dev)->uart_config);
 
 #ifdef CONFIG_UART_INTERRUPT_DRIVEN
@@ -483,16 +499,11 @@ static const struct uart_esp32_config uart_esp32_cfg_port_##idx = {	       \
 	.dev_conf = {							       \
 		.base =							       \
 		    (uint8_t *)DT_INST_REG_ADDR(idx), \
-		.sys_clk_freq =						       \
-			DT_PROP(DT_INST(0, cadence_tensilica_xtensa_lx6), clock_frequency),\
 		ESP32_UART_IRQ_HANDLER_FUNC(idx)			       \
 	},								       \
-									       \
+											   \
-	.peripheral = {							       \
+	.clock_name = DT_INST_CLOCKS_LABEL(idx),			       \
-		.clk = DPORT_UART##idx##_CLK_EN,			       \
+											   \
-		.rst = DPORT_UART##idx##_RST,				       \
-	},								       \
-									       \
 	.signals = {							       \
 		.tx_out = U##idx##TXD_OUT_IDX,				       \
 		.rx_in = U##idx##RXD_IN_IDX,				       \
@@ -509,7 +520,8 @@ static const struct uart_esp32_config uart_esp32_cfg_port_##idx = {	       \
 			.cts = DT_INST_PROP(idx, cts_pin),   \
 			))						       \
 	},								       \
-									       \
+											   \
+	.peripheral_id = (clock_control_subsys_t)DT_INST_CLOCKS_CELL(idx, offset), \
 	.irq = {							       \
 		.source = ETS_UART##idx##_INTR_SOURCE,			       \
 		.line = INST_##idx##_ESPRESSIF_ESP32_UART_IRQ_0,	       \

dts/xtensa/espressif/esp32.dtsi

@@ -21,14 +21,14 @@
 			device_type = "cpu";
 			compatible = "cadence,tensilica-xtensa-lx6";
 			reg = <0>;
-			clock-source = <ESP32_CLK_SRC_XTAL>;
+			clock-source = <ESP32_CLK_SRC_PLL>;
 		};
 
 		cpu1: cpu@1 {
 			device_type = "cpu";
 			compatible = "cadence,tensilica-xtensa-lx6";
 			reg = <1>;
-			clock-source = <ESP32_CLK_SRC_XTAL>;
+			clock-source = <ESP32_CLK_SRC_PLL>;
 		};
 
 	};
@@ -55,6 +55,7 @@
 			reg = <0x3ff40000 0x400>;
 			/* interrupts = <12>; - FIXME: Enable interrupts when interrupt-controller got supported in device tree */
 			label = "UART_0";
+			clocks = <&rtc ESP32_UART0_MODULE>;
 			status = "disabled";
 		};
 
@@ -63,6 +64,7 @@
 			reg = <0x3ff50000 0x400>;
 			/* interrupts = <17>; - FIXME: Enable interrupts when interrupt-controller got supported in device tree */
 			label = "UART_1";
+			clocks = <&rtc ESP32_UART1_MODULE>;
 			status = "disabled";
 		};
 
@@ -71,6 +73,7 @@
 			reg = <0x3ff6E000 0x400>;
 			/* interrupts = <18>; - FIXME: Enable interrupts when interrupt-controller got supported in device tree */
 			label = "UART_2";
+			clocks = <&rtc ESP32_UART2_MODULE>;
 			status = "disabled";
 		};
 
@@ -104,6 +107,7 @@
 			reg = <0x3ff53000 0x1000>;
 			/* interrupts = <8>; - FIXME: Enable interrupts when interrupt-controller got supported in device tree */
 			label = "I2C_0";
+			clocks = <&rtc ESP32_I2C_EXT0_MODULE>;
 			status = "disabled";
 		};
 
@@ -114,6 +118,7 @@
 			reg = <0x3ff67000 0x1000>;
 			/* interrupts = <9>; - FIXME: Enable interrupts when interrupt-controller got supported in device tree */
 			label = "I2C_1";
+			clocks = <&rtc ESP32_I2C_EXT1_MODULE>;
 			status = "disabled";
 		};
 

soc/xtensa/esp32/soc.h

@@ -14,17 +14,6 @@
 #include <stdbool.h>
 #include <arch/xtensa/arch.h>
 
-/**
- * @brief Struct to peripheral masks to enable peripheral
- * clock and reset peripherals.
- */
-struct esp32_peripheral {
-	/** Mask for clock peripheral */
-	int clk;
-	/** Mask for reset peripheral */
-	int rst;
-};
-
 static inline void esp32_set_mask32(uint32_t v, uint32_t mem_addr)
 {
 	sys_write32(sys_read32(mem_addr) | v, mem_addr);
@@ -35,12 +24,6 @@ static inline void esp32_clear_mask32(uint32_t v, uint32_t mem_addr)
 	sys_write32(sys_read32(mem_addr) & ~v, mem_addr);
 }
 
-static inline void esp32_enable_peripheral(const struct esp32_peripheral *peripheral)
-{
-	esp32_set_mask32(peripheral->clk, DPORT_PERIP_CLK_EN_REG);
-	esp32_clear_mask32(peripheral->rst, DPORT_PERIP_RST_EN_REG);
-}
-
 extern int esp32_rom_intr_matrix_set(int cpu_no,
 				     int interrupt_src,
 				     int interrupt_line);