1 files changed, 406 insertions, 0 deletions
diff --git a/src/soc/qualcomm/ipq40xx/uart.c b/src/soc/qualcomm/ipq40xx/uart.c
new file mode 100644
index 0000000000..99b2b055b7
--- /dev/null
+++ b/src/soc/qualcomm/ipq40xx/uart.c
@@ -0,0 +1,406 @@
+/*
+ * Copyright (c) 2012 The Linux Foundation. All rights reserved.
+ * Source : APQ8064 LK boot
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are
+ * met:
+ *     * Redistributions of source code must retain the above copyright
+ *       notice, this list of conditions and the following disclaimer.
+ *     * Redistributions in binary form must reproduce the above
+ *       copyright notice, this list of conditions and the following
+ *       disclaimer in the documentation and/or other materials provided
+ *       with the distribution.
+ *     * Neither the name of The Linux Foundation nor the names of its
+ *       contributors may be used to endorse or promote products derived
+ *       from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED "AS IS" AND ANY EXPRESS OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS
+ * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
+ * BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
+ * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE
+ * OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN
+ * IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include <arch/io.h>
+#include <boot/coreboot_tables.h>
+#include <console/console.h>
+#include <console/uart.h>
+#include <delay.h>
+#include <gpio.h>
+#include <soc/clock.h>
+#include <soc/gsbi.h>
+#include <soc/ipq_uart.h>
+#include <stdint.h>
+#include <stdlib.h>
+
+#define FIFO_DATA_SIZE	4
+
+typedef struct {
+	void *uart_dm_base;
+	void *uart_gsbi_base;
+	unsigned uart_gsbi;
+	uart_clk_mnd_t mnd_value;
+	gpio_func_data_t dbg_uart_gpio[NO_OF_DBG_UART_GPIOS];
+} uart_params_t;
+
+/*
+ * All constants lifted from u-boot's
+ * board/qcom/ipq40xx_cdp/ipq40xx_board_param.h
+ */
+static const uart_params_t uart_board_param = {
+	.uart_dm_base = (void *)UART4_DM_BASE,
+	.uart_gsbi_base = (void *)UART_GSBI4_BASE,
+	.uart_gsbi = GSBI_4,
+	.mnd_value = { 12, 625, 313 },
+		.dbg_uart_gpio = {
+			{
+				.gpio = 10,
+				.func = 1,
+				.dir = GPIO_OUTPUT,
+				.pull = GPIO_NO_PULL,
+				.drvstr = GPIO_12MA,
+				.enable = GPIO_DISABLE
+			},
+			{
+				.gpio = 11,
+				.func = 1,
+				.dir = GPIO_INPUT,
+				.pull = GPIO_NO_PULL,
+				.drvstr = GPIO_12MA,
+				.enable = GPIO_DISABLE
+			},
+		}
+};
+
+/**
+ * msm_boot_uart_dm_init_rx_transfer - Init Rx transfer
+ * @uart_dm_base: UART controller base address
+ */
+static unsigned int msm_boot_uart_dm_init_rx_transfer(void *uart_dm_base)
+{
+	/* Reset receiver */
+	write32(MSM_BOOT_UART_DM_CR(uart_dm_base),
+		MSM_BOOT_UART_DM_CMD_RESET_RX);
+
+	/* Enable receiver */
+	write32(MSM_BOOT_UART_DM_CR(uart_dm_base),
+		MSM_BOOT_UART_DM_CR_RX_ENABLE);
+	write32(MSM_BOOT_UART_DM_DMRX(uart_dm_base),
+		MSM_BOOT_UART_DM_DMRX_DEF_VALUE);
+
+	/* Clear stale event */
+	write32(MSM_BOOT_UART_DM_CR(uart_dm_base),
+		MSM_BOOT_UART_DM_CMD_RES_STALE_INT);
+
+	/* Enable stale event */
+	write32(MSM_BOOT_UART_DM_CR(uart_dm_base),
+		MSM_BOOT_UART_DM_GCMD_ENA_STALE_EVT);
+
+	return MSM_BOOT_UART_DM_E_SUCCESS;
+}
+
+#if IS_ENABLED(CONFIG_DRIVERS_UART)
+static unsigned int msm_boot_uart_dm_init(void  *uart_dm_base);
+
+/* Received data is valid or not */
+static int valid_data = 0;
+
+/* Received data */
+static unsigned int word = 0;
+
+/**
+ * msm_boot_uart_dm_read - reads a word from the RX FIFO.
+ * @data: location where the read data is stored
+ * @count: no of valid data in the FIFO
+ * @wait: indicates blocking call or not blocking call
+ *
+ * Reads a word from the RX FIFO. If no data is available blocks if
+ * @wait is true, else returns %MSM_BOOT_UART_DM_E_RX_NOT_READY.
+ */
+ #if 0 /* Not used yet */
+static unsigned int
+msm_boot_uart_dm_read(unsigned int *data, int *count, int wait)
+{
+	static int total_rx_data = 0;
+	static int rx_data_read = 0;
+	void *base;
+	uint32_t status_reg;
+
+	base = uart_board_param.uart_dm_base;
+
+	if (data == NULL)
+		return MSM_BOOT_UART_DM_E_INVAL;
+
+	status_reg = readl(MSM_BOOT_UART_DM_MISR(base));
+
+	/* Check for DM_RXSTALE for RX transfer to finish */
+	while (!(status_reg & MSM_BOOT_UART_DM_RXSTALE)) {
+		status_reg = readl(MSM_BOOT_UART_DM_MISR(base));
+		if (!wait)
+			return MSM_BOOT_UART_DM_E_RX_NOT_READY;
+	}
+
+	/* Check for Overrun error. We'll just reset Error Status */
+	if (readl(MSM_BOOT_UART_DM_SR(base)) &
+			MSM_BOOT_UART_DM_SR_UART_OVERRUN) {
+		writel(MSM_BOOT_UART_DM_CMD_RESET_ERR_STAT,
+			MSM_BOOT_UART_DM_CR(base));
+		total_rx_data = rx_data_read = 0;
+		msm_boot_uart_dm_init(base);
+		return MSM_BOOT_UART_DM_E_RX_NOT_READY;
+	}
+
+	/* Read UART_DM_RX_TOTAL_SNAP for actual number of bytes received */
+	if (total_rx_data == 0)
+		total_rx_data =  readl(MSM_BOOT_UART_DM_RX_TOTAL_SNAP(base));
+
+	/* Data available in FIFO; read a word. */
+	*data = readl(MSM_BOOT_UART_DM_RF(base, 0));
+
+	/* WAR for http://prism/CR/548280 */
+	if (*data == 0)
+		return MSM_BOOT_UART_DM_E_RX_NOT_READY;
+
+	/* increment the total count of chars we've read so far */
+	rx_data_read += FIFO_DATA_SIZE;
+
+	/* actual count of valid data in word */
+	*count = ((total_rx_data < rx_data_read) ?
+			(FIFO_DATA_SIZE - (rx_data_read - total_rx_data)) :
+			FIFO_DATA_SIZE);
+
+	/* If there are still data left in FIFO we'll read them before
+	 * initializing RX Transfer again
+	 */
+	if (rx_data_read < total_rx_data)
+		return MSM_BOOT_UART_DM_E_SUCCESS;
+
+	msm_boot_uart_dm_init_rx_transfer(base);
+	total_rx_data = rx_data_read = 0;
+
+	return MSM_BOOT_UART_DM_E_SUCCESS;
+}
+#endif
+
+void uart_tx_byte(int idx, unsigned char data)
+{
+	int num_of_chars = 1;
+	unsigned tx_data = 0;
+	void *base = uart_board_param.uart_dm_base;
+
+	/* Wait until transmit FIFO is empty. */
+	while (!(read32(MSM_BOOT_UART_DM_SR(base)) &
+		 MSM_BOOT_UART_DM_SR_TXEMT))
+		udelay(1);
+	/*
+	 * TX FIFO is ready to accept new character(s). First write number of
+	 * characters to be transmitted.
+	 */
+	write32(MSM_BOOT_UART_DM_NO_CHARS_FOR_TX(base), num_of_chars);
+
+	/* And now write the character(s) */
+	write32(MSM_BOOT_UART_DM_TF(base, 0), tx_data);
+}
+#endif /* CONFIG_SERIAL_UART */
+
+/*
+ * msm_boot_uart_dm_reset - resets UART controller
+ * @base: UART controller base address
+ */
+static unsigned int msm_boot_uart_dm_reset(void *base)
+{
+	write32(MSM_BOOT_UART_DM_CR(base), MSM_BOOT_UART_DM_CMD_RESET_RX);
+	write32(MSM_BOOT_UART_DM_CR(base), MSM_BOOT_UART_DM_CMD_RESET_TX);
+	write32(MSM_BOOT_UART_DM_CR(base),
+		MSM_BOOT_UART_DM_CMD_RESET_ERR_STAT);
+	write32(MSM_BOOT_UART_DM_CR(base), MSM_BOOT_UART_DM_CMD_RES_TX_ERR);
+	write32(MSM_BOOT_UART_DM_CR(base), MSM_BOOT_UART_DM_CMD_RES_STALE_INT);
+
+	return MSM_BOOT_UART_DM_E_SUCCESS;
+}
+
+/*
+ * msm_boot_uart_dm_init - initilaizes UART controller
+ * @uart_dm_base: UART controller base address
+ */
+static unsigned int msm_boot_uart_dm_init(void  *uart_dm_base)
+{
+	/* Configure UART mode registers MR1 and MR2 */
+	/* Hardware flow control isn't supported */
+	write32(MSM_BOOT_UART_DM_MR1(uart_dm_base), 0x0);
+
+	/* 8-N-1 configuration: 8 data bits - No parity - 1 stop bit */
+	write32(MSM_BOOT_UART_DM_MR2(uart_dm_base),
+		MSM_BOOT_UART_DM_8_N_1_MODE);
+
+	/* Configure Interrupt Mask register IMR */
+	write32(MSM_BOOT_UART_DM_IMR(uart_dm_base),
+		MSM_BOOT_UART_DM_IMR_ENABLED);
+
+	/*
+	 * Configure Tx and Rx watermarks configuration registers
+	 * TX watermark value is set to 0 - interrupt is generated when
+	 * FIFO level is less than or equal to 0
+	 */
+	write32(MSM_BOOT_UART_DM_TFWR(uart_dm_base),
+		MSM_BOOT_UART_DM_TFW_VALUE);
+
+	/* RX watermark value */
+	write32(MSM_BOOT_UART_DM_RFWR(uart_dm_base),
+		MSM_BOOT_UART_DM_RFW_VALUE);
+
+	/* Configure Interrupt Programming Register */
+	/* Set initial Stale timeout value */
+	write32(MSM_BOOT_UART_DM_IPR(uart_dm_base),
+		MSM_BOOT_UART_DM_STALE_TIMEOUT_LSB);
+
+	/* Configure IRDA if required */
+	/* Disabling IRDA mode */
+	write32(MSM_BOOT_UART_DM_IRDA(uart_dm_base), 0x0);
+
+	/* Configure hunt character value in HCR register */
+	/* Keep it in reset state */
+	write32(MSM_BOOT_UART_DM_HCR(uart_dm_base), 0x0);
+
+	/*
+	 * Configure Rx FIFO base address
+	 * Both TX/RX shares same SRAM and default is half-n-half.
+	 * Sticking with default value now.
+	 * As such RAM size is (2^RAM_ADDR_WIDTH, 32-bit entries).
+	 * We have found RAM_ADDR_WIDTH = 0x7f
+	 */
+
+	/* Issue soft reset command */
+	msm_boot_uart_dm_reset(uart_dm_base);
+
+	/* Enable/Disable Rx/Tx DM interfaces */
+	/* Data Mover not currently utilized. */
+	write32(MSM_BOOT_UART_DM_DMEN(uart_dm_base), 0x0);
+
+	/* Enable transmitter */
+	write32(MSM_BOOT_UART_DM_CR(uart_dm_base),
+		MSM_BOOT_UART_DM_CR_TX_ENABLE);
+
+	/* Initialize Receive Path */
+	msm_boot_uart_dm_init_rx_transfer(uart_dm_base);
+
+	return 0;
+}
+
+/**
+ * ipq40xx_uart_init - initializes UART
+ *
+ * Initializes clocks, GPIO and UART controller.
+ */
+void uart_init(int idx)
+{
+	/* Note int idx isn't used in this driver. */
+	void *dm_base;
+	void *gsbi_base;
+
+	dm_base = uart_board_param.uart_dm_base;
+
+	if (read32(MSM_BOOT_UART_DM_CSR(dm_base)) == UART_DM_CLK_RX_TX_BIT_RATE)
+		return; /* UART must have been already initialized. */
+
+	gsbi_base = uart_board_param.uart_gsbi_base;
+	ipq_configure_gpio(uart_board_param.dbg_uart_gpio,
+			   NO_OF_DBG_UART_GPIOS);
+
+	/* Configure the uart clock */
+	uart_clock_config(uart_board_param.uart_gsbi,
+		uart_board_param.mnd_value.m_value,
+		uart_board_param.mnd_value.n_value,
+		uart_board_param.mnd_value.d_value,
+		0);
+
+	write32(GSBI_CTRL_REG(gsbi_base),
+		GSBI_PROTOCOL_CODE_I2C_UART << GSBI_CTRL_REG_PROTOCOL_CODE_S);
+	write32(MSM_BOOT_UART_DM_CSR(dm_base), UART_DM_CLK_RX_TX_BIT_RATE);
+
+	/* Initialize UART_DM */
+	msm_boot_uart_dm_init(dm_base);
+}
+
+/* for the benefit of non-console uart init */
+void ipq40xx_uart_init(void)
+{
+	uart_init(0);
+}
+
+#if 0 /* Not used yet */
+uint32_t uartmem_getbaseaddr(void)
+{
+	return (uint32_t)uart_board_param.uart_dm_base;
+}
+#endif
+
+/**
+ * uart_tx_flush - transmits a string of data
+ * @s: string to transmit
+ */
+void uart_tx_flush(int idx)
+{
+	void *base = uart_board_param.uart_dm_base;
+
+	while (!(read32(MSM_BOOT_UART_DM_SR(base)) &
+		 MSM_BOOT_UART_DM_SR_TXEMT))
+		;
+}
+
+/**
+ * uart_can_rx_byte - checks if data available for reading
+ *
+ * Returns 1 if data available, 0 otherwise
+ */
+ #if 0 /* Not used yet */
+int uart_can_rx_byte(void)
+{
+	/* Return if data is already read */
+	if (valid_data)
+		return 1;
+
+	/* Read data from the FIFO */
+	if (msm_boot_uart_dm_read(&word, &valid_data, 0) !=
+	    MSM_BOOT_UART_DM_E_SUCCESS)
+		return 0;
+
+	return 1;
+}
+#endif
+
+#if IS_ENABLED(CONFIG_DRIVERS_UART)
+/**
+ * ipq40xx_serial_getc - reads a character
+ *
+ * Returns the character read from serial port.
+ */
+uint8_t uart_rx_byte(int idx)
+{
+	uint8_t byte;
+
+#if 0 /* Not used yet */
+	while (!uart_can_rx_byte())
+		;	/* wait for incoming data */
+#endif
+	byte = (uint8_t)(word & 0xff);
+	word = word >> 8;
+	valid_data--;
+
+	return byte;
+}
+#endif
+
+#ifndef __PRE_RAM__
+/* TODO: Implement function */
+void uart_fill_lb(void *data)
+{
+}
+#endif