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diff --git a/src/lib/uart_ipq806.c b/src/lib/uart_ipq806.c
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+/*
+ * 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);
+}