Adding upstream version 2.8.0+dfsg.upstream/2.8.0+dfsgupstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 181 insertions, 0 deletions

diff --git a/drivers/imx/uart/imx_uart.c b/drivers/imx/uart/imx_uart.c
new file mode 100644
index 0000000..dfe2e92
--- /dev/null
+++ b/drivers/imx/uart/imx_uart.c
@@ -0,0 +1,181 @@
+/*
+ * Copyright (c) Linaro 2018 Limited and Contributors. All rights reserved.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+#include <stdint.h>
+
+#include <platform_def.h>
+
+#include <arch.h>
+#include <lib/mmio.h>
+
+#include <imx_uart.h>
+
+/* TX/RX FIFO threshold */
+#define TX_RX_THRESH 2
+
+struct clk_div_factors {
+	uint32_t fcr_div;
+	uint32_t bmr_div;
+};
+
+static struct clk_div_factors clk_div[] = {
+	{
+		.fcr_div = IMX_UART_FCR_RFDIV1,
+		.bmr_div = 1,
+	},
+	{
+		.fcr_div = IMX_UART_FCR_RFDIV2,
+		.bmr_div = 2,
+	},
+	{
+		.fcr_div = IMX_UART_FCR_RFDIV3,
+		.bmr_div = 3,
+	},
+	{
+		.fcr_div = IMX_UART_FCR_RFDIV4,
+		.bmr_div = 4,
+	},
+	{
+		.fcr_div = IMX_UART_FCR_RFDIV5,
+		.bmr_div = 5,
+	},
+	{
+		.fcr_div = IMX_UART_FCR_RFDIV6,
+		.bmr_div = 6,
+	},
+	{
+		.fcr_div = IMX_UART_FCR_RFDIV7,
+		.bmr_div = 7,
+	},
+};
+
+static void write_reg(uintptr_t base, uint32_t offset, uint32_t val)
+{
+	mmio_write_32(base + offset, val);
+}
+
+static uint32_t read_reg(uintptr_t base, uint32_t offset)
+{
+	return mmio_read_32(base + offset);
+}
+
+int console_imx_uart_core_init(uintptr_t base_addr, unsigned int uart_clk,
+			       unsigned int baud_rate)
+{
+	uint32_t val;
+	uint8_t clk_idx = 1;
+
+	/* Reset UART */
+	write_reg(base_addr, IMX_UART_CR2_OFFSET, 0);
+	do {
+		val = read_reg(base_addr, IMX_UART_CR2_OFFSET);
+	} while (!(val & IMX_UART_CR2_SRST));
+
+	/* Enable UART */
+	write_reg(base_addr, IMX_UART_CR1_OFFSET, IMX_UART_CR1_UARTEN);
+
+	/* Ignore RTS, 8N1, enable tx/rx, disable reset */
+	val = (IMX_UART_CR2_IRTS | IMX_UART_CR2_WS | IMX_UART_CR2_TXEN |
+	       IMX_UART_CR2_RXEN | IMX_UART_CR2_SRST);
+	write_reg(base_addr, IMX_UART_CR2_OFFSET, val);
+
+	/* No parity, autobaud detect-old, rxdmuxsel=1 (fixed i.mx7) */
+	val = IMX_UART_CR3_ADNIMP | IMX_UART_CR3_RXDMUXSEL;
+	write_reg(base_addr, IMX_UART_CR3_OFFSET, val);
+
+	/* Set CTS FIFO trigger to 32 bytes bits 15:10 */
+	write_reg(base_addr, IMX_UART_CR4_OFFSET, 0x8000);
+
+	/* TX/RX-thresh = 2 bytes, DTE (bit6 = 0), refclk @24MHz / 4 */
+	val = IMX_UART_FCR_TXTL(TX_RX_THRESH) | IMX_UART_FCR_RXTL(TX_RX_THRESH) |
+	      clk_div[clk_idx].fcr_div;
+	#ifdef IMX_UART_DTE
+		/* Set DTE (bit6 = 1) */
+		val |= IMX_UART_FCR_DCEDTE;
+	#endif
+	write_reg(base_addr, IMX_UART_FCR_OFFSET, val);
+
+	/*
+	 * The equation for BAUD rate calculation is
+	 * RefClk = Supplied clock / FCR_DIVx
+	 *
+	 * BAUD  =    Refclk
+	 *         ------------
+	 *       16 x (UBMR + 1/ UBIR + 1)
+	 *
+	 * We write 0x0f into UBIR to remove the 16 mult
+	 * BAUD  =    6000000
+	 *         ------------
+	 *       16 x (UBMR + 1/ 15 + 1)
+	 */
+
+	write_reg(base_addr, IMX_UART_BIR_OFFSET, 0x0f);
+	val = ((uart_clk / clk_div[clk_idx].bmr_div) / baud_rate) - 1;
+	write_reg(base_addr, IMX_UART_BMR_OFFSET, val);
+
+	return 0;
+}
+
+/* --------------------------------------------------------
+ * int console_core_putc(int c, uintptr_t base_addr)
+ * Function to output a character over the console. It
+ * returns the character printed on success or -1 on error.
+ * In : r0 - character to be printed
+ *      r1 - console base address
+ * Out : return -1 on error else return character.
+ * Clobber list : r2
+ * --------------------------------------------------------
+ */
+int console_imx_uart_core_putc(int c, uintptr_t base_addr)
+{
+	uint32_t val;
+
+	if (c == '\n')
+		console_imx_uart_core_putc('\r', base_addr);
+
+	/* Write data */
+	write_reg(base_addr, IMX_UART_TXD_OFFSET, c);
+
+	/* Wait for transmit */
+	do {
+		val = read_reg(base_addr, IMX_UART_STAT2_OFFSET);
+	} while (!(val & IMX_UART_STAT2_TXDC));
+
+	return 0;
+}
+
+/*
+ * Function to get a character from the console.
+ * It returns the character grabbed on success
+ * or -1 on error.
+ * In : r0 - console base address
+ * Clobber list : r0, r1
+ * ---------------------------------------------
+ */
+int console_imx_uart_core_getc(uintptr_t base_addr)
+{
+	uint32_t val;
+
+	val = read_reg(base_addr, IMX_UART_TS_OFFSET);
+	if (val & IMX_UART_TS_RXEMPTY)
+		return -1;
+
+	val = read_reg(base_addr, IMX_UART_RXD_OFFSET);
+	return (int)(val & 0x000000FF);
+}
+
+/*
+ * Function to force a write of all buffered
+ * data that hasn't been output.
+ * In : r0 - console base address
+ * Out : void
+ * Clobber list : r0, r1
+ * ---------------------------------------------
+ */
+void console_imx_uart_core_flush(uintptr_t base_addr)
+{
+}
+