stm32mp1: Add PMIC support

If a PMIC companion chip is present on board, it has to be configured
for regulators supplies.
This check is done with board DT configuration.

Signed-off-by: Yann Gautier <yann.gautier@st.com>
Signed-off-by: Pascal Paillet <p.paillet@st.com>
diff --git a/drivers/st/pmic/stm32mp1_pmic.c b/drivers/st/pmic/stm32mp1_pmic.c
new file mode 100644
index 0000000..958de08
--- /dev/null
+++ b/drivers/st/pmic/stm32mp1_pmic.c
@@ -0,0 +1,346 @@
+/*
+ * Copyright (c) 2017-2018, STMicroelectronics - All Rights Reserved
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+#include <debug.h>
+#include <delay_timer.h>
+#include <errno.h>
+#include <libfdt.h>
+#include <mmio.h>
+#include <mmio.h>
+#include <platform_def.h>
+#include <stdbool.h>
+#include <stm32_gpio.h>
+#include <stm32mp1_clk.h>
+#include <stm32mp1_dt.h>
+#include <stm32mp1_pmic.h>
+#include <stpmu1.h>
+#include <utils_def.h>
+
+/* I2C Timing hard-coded value, for I2C clock source is HSI at 64MHz */
+#define I2C_TIMING			0x10D07DB5
+
+#define I2C_TIMEOUT			0xFFFFF
+
+#define MASK_RESET_BUCK3		BIT(2)
+
+#define STPMU1_LDO12356_OUTPUT_MASK	(uint8_t)(GENMASK(6, 2))
+#define STPMU1_LDO12356_OUTPUT_SHIFT	2
+#define STPMU1_LDO3_MODE		(uint8_t)(BIT(7))
+#define STPMU1_LDO3_DDR_SEL		31U
+#define STPMU1_LDO3_1800000		(9U << STPMU1_LDO12356_OUTPUT_SHIFT)
+
+#define STPMU1_BUCK_OUTPUT_SHIFT	2
+#define STPMU1_BUCK3_1V8		(39U << STPMU1_BUCK_OUTPUT_SHIFT)
+
+#define STPMU1_DEFAULT_START_UP_DELAY_MS	1
+
+static struct i2c_handle_s i2c_handle;
+static uint32_t pmic_i2c_addr;
+
+static int dt_get_pmic_node(void *fdt)
+{
+	return fdt_node_offset_by_compatible(fdt, -1, "st,stpmu1");
+}
+
+bool dt_check_pmic(void)
+{
+	int node;
+	void *fdt;
+
+	if (fdt_get_address(&fdt) == 0) {
+		return false;
+	}
+
+	node = dt_get_pmic_node(fdt);
+	if (node < 0) {
+		VERBOSE("%s: No PMIC node found in DT\n", __func__);
+		return false;
+	}
+
+	return fdt_check_status(node);
+}
+
+static int dt_pmic_i2c_config(struct dt_node_info *i2c_info)
+{
+	int pmic_node, i2c_node;
+	void *fdt;
+	const fdt32_t *cuint;
+
+	if (fdt_get_address(&fdt) == 0) {
+		return -ENOENT;
+	}
+
+	pmic_node = dt_get_pmic_node(fdt);
+	if (pmic_node < 0) {
+		return -FDT_ERR_NOTFOUND;
+	}
+
+	cuint = fdt_getprop(fdt, pmic_node, "reg", NULL);
+	if (cuint == NULL) {
+		return -FDT_ERR_NOTFOUND;
+	}
+
+	pmic_i2c_addr = fdt32_to_cpu(*cuint) << 1;
+	if (pmic_i2c_addr > UINT16_MAX) {
+		return -EINVAL;
+	}
+
+	i2c_node = fdt_parent_offset(fdt, pmic_node);
+	if (i2c_node < 0) {
+		return -FDT_ERR_NOTFOUND;
+	}
+
+	dt_fill_device_info(i2c_info, i2c_node);
+	if (i2c_info->base == 0U) {
+		return -FDT_ERR_NOTFOUND;
+	}
+
+	return dt_set_pinctrl_config(i2c_node);
+}
+
+int dt_pmic_enable_boot_on_regulators(void)
+{
+	int pmic_node, regulators_node, regulator_node;
+	void *fdt;
+
+	if (fdt_get_address(&fdt) == 0) {
+		return -ENOENT;
+	}
+
+	pmic_node = dt_get_pmic_node(fdt);
+	if (pmic_node < 0) {
+		return -FDT_ERR_NOTFOUND;
+	}
+
+	regulators_node = fdt_subnode_offset(fdt, pmic_node, "regulators");
+
+	fdt_for_each_subnode(regulator_node, fdt, regulators_node) {
+		const fdt32_t *cuint;
+		const char *node_name;
+		uint16_t voltage;
+
+		if (fdt_getprop(fdt, regulator_node, "regulator-boot-on",
+				NULL) == NULL) {
+			continue;
+		}
+
+		cuint = fdt_getprop(fdt, regulator_node,
+				    "regulator-min-microvolt", NULL);
+		if (cuint == NULL) {
+			continue;
+		}
+
+		/* DT uses microvolts, whereas driver awaits millivolts */
+		voltage = (uint16_t)(fdt32_to_cpu(*cuint) / 1000U);
+		node_name = fdt_get_name(fdt, regulator_node, NULL);
+
+		if (stpmu1_is_regulator_enabled(node_name) == 0U) {
+			int status;
+
+			status = stpmu1_regulator_voltage_set(node_name,
+							      voltage);
+			if (status != 0) {
+				return status;
+			}
+
+			status = stpmu1_regulator_enable(node_name);
+			if (status != 0) {
+				return status;
+			}
+		}
+	}
+
+	return 0;
+}
+
+void initialize_pmic_i2c(void)
+{
+	int ret;
+	struct dt_node_info i2c_info;
+
+	if (dt_pmic_i2c_config(&i2c_info) != 0) {
+		ERROR("I2C configuration failed\n");
+		panic();
+	}
+
+	if (stm32mp1_clk_enable((uint32_t)i2c_info.clock) < 0) {
+		ERROR("I2C clock enable failed\n");
+		panic();
+	}
+
+	/* Initialize PMIC I2C */
+	i2c_handle.i2c_base_addr		= i2c_info.base;
+	i2c_handle.i2c_init.timing		= I2C_TIMING;
+	i2c_handle.i2c_init.own_address1	= pmic_i2c_addr;
+	i2c_handle.i2c_init.addressing_mode	= I2C_ADDRESSINGMODE_7BIT;
+	i2c_handle.i2c_init.dual_address_mode	= I2C_DUALADDRESS_DISABLE;
+	i2c_handle.i2c_init.own_address2	= 0;
+	i2c_handle.i2c_init.own_address2_masks	= I2C_OAR2_OA2NOMASK;
+	i2c_handle.i2c_init.general_call_mode	= I2C_GENERALCALL_DISABLE;
+	i2c_handle.i2c_init.no_stretch_mode	= I2C_NOSTRETCH_DISABLE;
+
+	ret = stm32_i2c_init(&i2c_handle);
+	if (ret != 0) {
+		ERROR("Cannot initialize I2C %x (%d)\n",
+		      i2c_handle.i2c_base_addr, ret);
+		panic();
+	}
+
+	ret = stm32_i2c_config_analog_filter(&i2c_handle,
+					     I2C_ANALOGFILTER_ENABLE);
+	if (ret != 0) {
+		ERROR("Cannot initialize I2C analog filter (%d)\n", ret);
+		panic();
+	}
+
+	ret = stm32_i2c_is_device_ready(&i2c_handle, (uint16_t)pmic_i2c_addr, 1,
+					I2C_TIMEOUT);
+	if (ret != 0) {
+		ERROR("I2C device not ready (%d)\n", ret);
+		panic();
+	}
+
+	stpmu1_bind_i2c(&i2c_handle, (uint16_t)pmic_i2c_addr);
+}
+
+void initialize_pmic(void)
+{
+	int status;
+	uint8_t read_val;
+
+	initialize_pmic_i2c();
+
+	status = stpmu1_register_read(VERSION_STATUS_REG, &read_val);
+	if (status != 0) {
+		panic();
+	}
+
+	INFO("PMIC version = 0x%x\n", read_val);
+
+	/* Keep VDD on during the reset cycle */
+	status = stpmu1_register_update(MASK_RESET_BUCK_REG,
+					MASK_RESET_BUCK3,
+					MASK_RESET_BUCK3);
+	if (status != 0) {
+		panic();
+	}
+}
+
+int pmic_ddr_power_init(enum ddr_type ddr_type)
+{
+	bool buck3_at_1v8 = false;
+	uint8_t read_val;
+	int status;
+
+	switch (ddr_type) {
+	case STM32MP_DDR3:
+		/* Set LDO3 to sync mode */
+		status = stpmu1_register_read(LDO3_CONTROL_REG, &read_val);
+		if (status != 0) {
+			return status;
+		}
+
+		read_val &= ~STPMU1_LDO3_MODE;
+		read_val &= ~STPMU1_LDO12356_OUTPUT_MASK;
+		read_val |= STPMU1_LDO3_DDR_SEL << STPMU1_LDO12356_OUTPUT_SHIFT;
+
+		status = stpmu1_register_write(LDO3_CONTROL_REG, read_val);
+		if (status != 0) {
+			return status;
+		}
+
+		status = stpmu1_regulator_voltage_set("buck2", 1350);
+		if (status != 0) {
+			return status;
+		}
+
+		status = stpmu1_regulator_enable("buck2");
+		if (status != 0) {
+			return status;
+		}
+
+		mdelay(STPMU1_DEFAULT_START_UP_DELAY_MS);
+
+		status = stpmu1_regulator_enable("vref_ddr");
+		if (status != 0) {
+			return status;
+		}
+
+		mdelay(STPMU1_DEFAULT_START_UP_DELAY_MS);
+
+		status = stpmu1_regulator_enable("ldo3");
+		if (status != 0) {
+			return status;
+		}
+
+		mdelay(STPMU1_DEFAULT_START_UP_DELAY_MS);
+		break;
+
+	case STM32MP_LPDDR2:
+		/*
+		 * Set LDO3 to 1.8V
+		 * Set LDO3 to bypass mode if BUCK3 = 1.8V
+		 * Set LDO3 to normal mode if BUCK3 != 1.8V
+		 */
+		status = stpmu1_register_read(BUCK3_CONTROL_REG, &read_val);
+		if (status != 0) {
+			return status;
+		}
+
+		if ((read_val & STPMU1_BUCK3_1V8) == STPMU1_BUCK3_1V8) {
+			buck3_at_1v8 = true;
+		}
+
+		status = stpmu1_register_read(LDO3_CONTROL_REG, &read_val);
+		if (status != 0) {
+			return status;
+		}
+
+		read_val &= ~STPMU1_LDO3_MODE;
+		read_val &= ~STPMU1_LDO12356_OUTPUT_MASK;
+		read_val |= STPMU1_LDO3_1800000;
+		if (buck3_at_1v8) {
+			read_val |= STPMU1_LDO3_MODE;
+		}
+
+		status = stpmu1_register_write(LDO3_CONTROL_REG, read_val);
+		if (status != 0) {
+			return status;
+		}
+
+		status = stpmu1_regulator_voltage_set("buck2", 1200);
+		if (status != 0) {
+			return status;
+		}
+
+		status = stpmu1_regulator_enable("ldo3");
+		if (status != 0) {
+			return status;
+		}
+
+		mdelay(STPMU1_DEFAULT_START_UP_DELAY_MS);
+
+		status = stpmu1_regulator_enable("buck2");
+		if (status != 0) {
+			return status;
+		}
+
+		mdelay(STPMU1_DEFAULT_START_UP_DELAY_MS);
+
+		status = stpmu1_regulator_enable("vref_ddr");
+		if (status != 0) {
+			return status;
+		}
+
+		mdelay(STPMU1_DEFAULT_START_UP_DELAY_MS);
+		break;
+
+	default:
+		break;
+	};
+
+	return 0;
+}