ipq8064: prepare UART driver for use in coreboot

These driver needs to be in src/lib, and the include file needs to be
renamed to avoid collision with the top level uart.h.

BUG=chrome-os-partner:27784
TEST=emerge-storm coreboot still works

Original-Change-Id: Ie12f44e055bbef0eb8b1a3ffc8d6742e7a446942
Original-Signed-off-by: Vadim Bendebury <vbendeb@chromium.org>
Original-Reviewed-on: https://chromium-review.googlesource.com/196393
(cherry picked from commit c5618fd418642f5b009582f5f6bc51f7c9d54bec)
Signed-off-by: Marc Jones <marc.jones@se-eng.com>

Change-Id: I5e25ae350ac5e71b47a0daef078b03cc5ac35401
Reviewed-on: http://review.coreboot.org/7270
Tested-by: build bot (Jenkins)
Reviewed-by: Stefan Reinauer <stefan.reinauer@coreboot.org>

1 files changed, 440 insertions, 0 deletions

diff --git a/src/lib/uart_ipq806.c b/src/lib/uart_ipq806.c
new file mode 100644
index 0000000000..c65f876821
--- /dev/null
+++ b/src/lib/uart_ipq806.c
@@ -0,0 +1,440 @@
+/*
+ * Copyright (c) 2012 The Linux Foundation. All rights reserved.
+ * Source : APQ8064 LK boot
+ *
+ * Copyright (c) 2011-2012, Code Aurora Forum. All rights reserved.
+ *
+ * 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 Google, Inc. 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 BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE 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 <common.h>
+#include <asm/arch-ipq806x/gsbi.h>
+#include <asm/arch-ipq806x/clock.h>
+#include <asm/arch-ipq806x/uart.h>
+#include <serial.h>
+
+#define FIFO_DATA_SIZE	4
+
+extern board_ipq806x_params_t *gboard_param;
+
+static unsigned int msm_boot_uart_dm_init(unsigned int  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_init_rx_transfer - Init Rx transfer
+ * @uart_dm_base: UART controller base address
+ */
+static unsigned int msm_boot_uart_dm_init_rx_transfer(unsigned int uart_dm_base)
+{
+	/* Reset receiver */
+	writel(MSM_BOOT_UART_DM_CMD_RESET_RX,
+		MSM_BOOT_UART_DM_CR(uart_dm_base));
+
+	/* Enable receiver */
+	writel(MSM_BOOT_UART_DM_CR_RX_ENABLE,
+		MSM_BOOT_UART_DM_CR(uart_dm_base));
+	writel(MSM_BOOT_UART_DM_DMRX_DEF_VALUE,
+		MSM_BOOT_UART_DM_DMRX(uart_dm_base));
+
+	/* Clear stale event */
+	writel(MSM_BOOT_UART_DM_CMD_RES_STALE_INT,
+		MSM_BOOT_UART_DM_CR(uart_dm_base));
+
+	/* Enable stale event */
+	writel(MSM_BOOT_UART_DM_GCMD_ENA_STALE_EVT,
+		MSM_BOOT_UART_DM_CR(uart_dm_base));
+
+	return MSM_BOOT_UART_DM_E_SUCCESS;
+}
+
+/**
+ * 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.
+ */
+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;
+	unsigned int  base = 0;
+	uint32_t status_reg;
+
+	base = gboard_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;
+}
+
+/**
+ * msm_boot_uart_replace_lr_with_cr - replaces "\n" with "\r\n"
+ * @data_in:      characters to be converted
+ * @num_of_chars: no. of characters
+ * @data_out:     location where converted chars are stored
+ *
+ * Replace linefeed char "\n" with carriage return + linefeed
+ * "\r\n". Currently keeping it simple than efficient.
+ */
+static unsigned int
+msm_boot_uart_replace_lr_with_cr(char *data_in,
+                                 int num_of_chars,
+                                 char *data_out, int *num_of_chars_out)
+{
+        int i = 0, j = 0;
+
+        if ((data_in == NULL) || (data_out == NULL) || (num_of_chars < 0))
+                return MSM_BOOT_UART_DM_E_INVAL;
+
+        for (i = 0, j = 0; i < num_of_chars; i++, j++) {
+                if (data_in[i] == '\n')
+                        data_out[j++] = '\r';
+
+                data_out[j] = data_in[i];
+        }
+
+        *num_of_chars_out = j;
+
+        return MSM_BOOT_UART_DM_E_SUCCESS;
+}
+
+/**
+ * msm_boot_uart_dm_write - transmit data
+ * @data:          data to transmit
+ * @num_of_chars:  no. of bytes to transmit
+ *
+ * Writes the data to the TX FIFO. If no space is available blocks
+ * till space becomes available.
+ */
+static unsigned int
+msm_boot_uart_dm_write(char *data, unsigned int num_of_chars)
+{
+	unsigned int tx_word_count = 0;
+	unsigned int tx_char_left = 0, tx_char = 0;
+	unsigned int tx_word = 0;
+	int i = 0;
+	char *tx_data = NULL;
+	char new_data[1024];
+	unsigned int base = gboard_param->uart_dm_base;
+
+        if ((data == NULL) || (num_of_chars <= 0))
+                return MSM_BOOT_UART_DM_E_INVAL;
+
+        /* Replace line-feed (/n) with carriage-return + line-feed (/r/n) */
+        msm_boot_uart_replace_lr_with_cr(data, num_of_chars, new_data, &i);
+
+        tx_data = new_data;
+        num_of_chars = i;
+
+        /* Write to NO_CHARS_FOR_TX register number of characters
+        * to be transmitted. However, before writing TX_FIFO must
+        * be empty as indicated by TX_READY interrupt in IMR register
+        */
+        /* Check if transmit FIFO is empty.
+        * If not we'll wait for TX_READY interrupt. */
+
+        if (!(readl(MSM_BOOT_UART_DM_SR(base)) & MSM_BOOT_UART_DM_SR_TXEMT)) {
+                while (!(readl(MSM_BOOT_UART_DM_ISR(base)) & MSM_BOOT_UART_DM_TX_READY))
+                        __udelay(1);
+        }
+
+        /* We are here. FIFO is ready to be written. */
+        /* Write number of characters to be written */
+        writel(num_of_chars, MSM_BOOT_UART_DM_NO_CHARS_FOR_TX(base));
+
+        /* Clear TX_READY interrupt */
+        writel(MSM_BOOT_UART_DM_GCMD_RES_TX_RDY_INT, MSM_BOOT_UART_DM_CR(base));
+
+        /* We use four-character word FIFO. So we need to divide data into
+        * four characters and write in UART_DM_TF register */
+        tx_word_count = (num_of_chars % 4) ? ((num_of_chars / 4) + 1) :
+                        (num_of_chars / 4);
+        tx_char_left = num_of_chars;
+
+        for (i = 0; i < (int)tx_word_count; i++) {
+                tx_char = (tx_char_left < 4) ? tx_char_left : 4;
+                PACK_CHARS_INTO_WORDS(tx_data, tx_char, tx_word);
+
+                /* Wait till TX FIFO has space */
+                while (!(readl(MSM_BOOT_UART_DM_SR(base)) & MSM_BOOT_UART_DM_SR_TXRDY))
+                        __udelay(1);
+
+                /* TX FIFO has space. Write the chars */
+                writel(tx_word, MSM_BOOT_UART_DM_TF(base, 0));
+                tx_char_left = num_of_chars - (i + 1) * 4;
+                tx_data = tx_data + 4;
+        }
+
+        return MSM_BOOT_UART_DM_E_SUCCESS;
+}
+
+/*
+ * msm_boot_uart_dm_reset - resets UART controller
+ * @base: UART controller base address
+ */
+static unsigned int msm_boot_uart_dm_reset(unsigned int base)
+{
+	writel(MSM_BOOT_UART_DM_CMD_RESET_RX, MSM_BOOT_UART_DM_CR(base));
+	writel(MSM_BOOT_UART_DM_CMD_RESET_TX, MSM_BOOT_UART_DM_CR(base));
+	writel(MSM_BOOT_UART_DM_CMD_RESET_ERR_STAT, MSM_BOOT_UART_DM_CR(base));
+	writel(MSM_BOOT_UART_DM_CMD_RES_TX_ERR, MSM_BOOT_UART_DM_CR(base));
+	writel(MSM_BOOT_UART_DM_CMD_RES_STALE_INT, MSM_BOOT_UART_DM_CR(base));
+
+	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(unsigned int  uart_dm_base)
+{
+	/* Configure UART mode registers MR1 and MR2 */
+	/* Hardware flow control isn't supported */
+	writel(0x0, MSM_BOOT_UART_DM_MR1(uart_dm_base));
+
+	/* 8-N-1 configuration: 8 data bits - No parity - 1 stop bit */
+	writel(MSM_BOOT_UART_DM_8_N_1_MODE, MSM_BOOT_UART_DM_MR2(uart_dm_base));
+
+	/* Configure Interrupt Mask register IMR */
+	writel(MSM_BOOT_UART_DM_IMR_ENABLED, MSM_BOOT_UART_DM_IMR(uart_dm_base));
+
+	/*
+	 * 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
+	 */
+	writel(MSM_BOOT_UART_DM_TFW_VALUE, MSM_BOOT_UART_DM_TFWR(uart_dm_base));
+
+	/* RX watermark value */
+	writel(MSM_BOOT_UART_DM_RFW_VALUE, MSM_BOOT_UART_DM_RFWR(uart_dm_base));
+
+	/* Configure Interrupt Programming Register */
+	/* Set initial Stale timeout value */
+	writel(MSM_BOOT_UART_DM_STALE_TIMEOUT_LSB,
+		MSM_BOOT_UART_DM_IPR(uart_dm_base));
+
+	/* Configure IRDA if required */
+	/* Disabling IRDA mode */
+	writel(0x0, MSM_BOOT_UART_DM_IRDA(uart_dm_base));
+
+	/* Configure hunt character value in HCR register */
+	/* Keep it in reset state */
+	writel(0x0, MSM_BOOT_UART_DM_HCR(uart_dm_base));
+
+	/*
+	 * 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. */
+	writel(0x0, MSM_BOOT_UART_DM_DMEN(uart_dm_base));
+
+	/* Enable transmitter */
+	writel(MSM_BOOT_UART_DM_CR_TX_ENABLE,
+		MSM_BOOT_UART_DM_CR(uart_dm_base));
+
+	/* Initialize Receive Path */
+	msm_boot_uart_dm_init_rx_transfer(uart_dm_base);
+
+	return 0;
+}
+
+/**
+ * uart_dm_init - initializes UART
+ *
+ * Initializes clocks, GPIO and UART controller.
+ */
+static int uart_dm_init(void)
+{
+	unsigned int dm_base, gsbi_base;
+
+	dm_base = gboard_param->uart_dm_base;
+	gsbi_base = gboard_param->uart_gsbi_base;
+	ipq_configure_gpio(gboard_param->dbg_uart_gpio, NO_OF_DBG_UART_GPIOS);
+
+	/* Configure the uart clock */
+        uart_clock_config(gboard_param->uart_gsbi,
+		gboard_param->mnd_value.m_value,
+		gboard_param->mnd_value.n_value,
+		gboard_param->mnd_value.d_value,
+		gboard_param->clk_dummy);
+
+	writel(GSBI_PROTOCOL_CODE_I2C_UART <<
+		GSBI_CTRL_REG_PROTOCOL_CODE_S,
+		GSBI_CTRL_REG(gsbi_base));
+        writel(UART_DM_CLK_RX_TX_BIT_RATE, MSM_BOOT_UART_DM_CSR(dm_base));
+	/* Intialize UART_DM */
+	msm_boot_uart_dm_init(dm_base);
+
+	return 0;
+}
+
+/**
+ * ipq806x_serial_putc - transmits a character
+ * @c: character to transmit
+ */
+static void ipq806x_serial_putc(char c)
+{
+        msm_boot_uart_dm_write(&c, 1);
+}
+
+/**
+ * ipq806x_serial_puts - transmits a string of data
+ * @s: string to transmit
+ */
+static void ipq806x_serial_puts(const char *s)
+{
+        while (*s != '\0')
+                serial_putc(*s++);
+}
+
+/**
+ * ipq806x_serial_tstc - checks if data available for reading
+ *
+ * Returns 1 if data available, 0 otherwise
+ */
+static int ipq806x_serial_tstc(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;
+}
+
+/**
+ * ipq806x_serial_getc - reads a character
+ *
+ * Returns the character read from serial port.
+ */
+static int ipq806x_serial_getc(void)
+{
+	int byte;
+
+	while (!serial_tstc()) {
+		/* wait for incoming data */
+	}
+
+	byte = (int)word & 0xff;
+	word = word >> 8;
+	valid_data--;
+
+	return byte;
+}
+
+static struct serial_device ipq_serial_device = {
+	.name = "ipq_serial",
+	.start = uart_dm_init,
+	.getc = ipq806x_serial_getc,
+	.tstc = ipq806x_serial_tstc,
+	.putc = ipq806x_serial_putc,
+	.puts = ipq806x_serial_puts,
+};
+
+__weak struct serial_device *default_serial_console(void)
+{
+	return &ipq_serial_device;
+}
+
+/**
+ * ipq806x_serial_init - initializes serial controller
+ */
+void ipq806x_serial_initialize(void)
+{
+	serial_register(&ipq_serial_device);
+}