2 * (C) Copyright 2013-2016 Freescale Semiconductor, Inc.
4 * SPDX-License-Identifier: GPL-2.0+
13 #include <linux/compiler.h>
14 #include <asm/arch/imx-regs.h>
15 #include <asm/arch/clock.h>
17 #define US1_TDRE (1 << 7)
18 #define US1_RDRF (1 << 5)
19 #define UC2_TE (1 << 3)
20 #define LINCR1_INIT (1 << 0)
21 #define LINCR1_MME (1 << 4)
22 #define LINCR1_BF (1 << 7)
23 #define LINSR_LINS_INITMODE (0x00001000)
24 #define LINSR_LINS_MASK (0x0000F000)
25 #define UARTCR_UART (1 << 0)
26 #define UARTCR_WL0 (1 << 1)
27 #define UARTCR_PCE (1 << 2)
28 #define UARTCR_PC0 (1 << 3)
29 #define UARTCR_TXEN (1 << 4)
30 #define UARTCR_RXEN (1 << 5)
31 #define UARTCR_PC1 (1 << 6)
32 #define UARTSR_DTF (1 << 1)
33 #define UARTSR_DRF (1 << 2)
34 #define UARTSR_RMB (1 << 9)
36 DECLARE_GLOBAL_DATA_PTR;
38 static void _linflex_serial_setbrg(struct linflex_fsl *base, int baudrate)
40 u32 clk = mxc_get_clock(MXC_UART_CLK);
44 baudrate = CONFIG_BAUDRATE;
46 ibr = (u32) (clk / (16 * gd->baudrate));
47 fbr = (u32) (clk % (16 * gd->baudrate)) * 16;
49 __raw_writel(ibr, &base->linibrr);
50 __raw_writel(fbr, &base->linfbrr);
53 static int _linflex_serial_getc(struct linflex_fsl *base)
57 if (!(__raw_readb(&base->uartsr) & UARTSR_DRF))
60 if (!(__raw_readl(&base->uartsr) & UARTSR_RMB))
63 c = __raw_readl(&base->bdrm);
64 __raw_writeb((__raw_readb(&base->uartsr) | (UARTSR_DRF | UARTSR_RMB)),
69 static int _linflex_serial_putc(struct linflex_fsl *base, const char c)
71 __raw_writeb(c, &base->bdrl);
74 if (!(__raw_readb(&base->uartsr) & UARTSR_DTF))
77 __raw_writeb((__raw_readb(&base->uartsr) | UARTSR_DTF), &base->uartsr);
83 * Initialise the serial port with the given baudrate. The settings
84 * are always 8 data bits, no parity, 1 stop bit, no start bits.
86 static int _linflex_serial_init(struct linflex_fsl *base)
90 /* set the Linflex in master mode amd activate by-pass filter */
91 ctrl = LINCR1_BF | LINCR1_MME;
92 __raw_writel(ctrl, &base->lincr1);
96 __raw_writel(ctrl, &base->lincr1);
98 /* waiting for init mode entry - TODO: add a timeout */
99 while ((__raw_readl(&base->linsr) & LINSR_LINS_MASK) !=
100 LINSR_LINS_INITMODE);
102 /* set UART bit to allow writing other bits */
103 __raw_writel(UARTCR_UART, &base->uartcr);
105 /* provide data bits, parity, stop bit, etc */
108 /* 8 bit data, no parity, Tx and Rx enabled, UART mode */
109 __raw_writel(UARTCR_PC1 | UARTCR_RXEN | UARTCR_TXEN | UARTCR_PC0
110 | UARTCR_WL0 | UARTCR_UART, &base->uartcr);
112 ctrl = __raw_readl(&base->lincr1);
113 ctrl &= ~LINCR1_INIT;
114 __raw_writel(ctrl, &base->lincr1); /* end init mode */
119 struct linflex_serial_platdata {
120 struct linflex_fsl *base_addr;
121 u8 port_id; /* do we need this? */
124 struct linflex_serial_priv {
125 struct linflex_fsl *lfuart;
128 int linflex_serial_setbrg(struct udevice *dev, int baudrate)
130 struct linflex_serial_priv *priv = dev_get_priv(dev);
132 _linflex_serial_setbrg(priv->lfuart, baudrate);
137 static int linflex_serial_getc(struct udevice *dev)
139 struct linflex_serial_priv *priv = dev_get_priv(dev);
141 return _linflex_serial_getc(priv->lfuart);
144 static int linflex_serial_putc(struct udevice *dev, const char ch)
147 struct linflex_serial_priv *priv = dev_get_priv(dev);
149 return _linflex_serial_putc(priv->lfuart, ch);
152 static int linflex_serial_pending(struct udevice *dev, bool input)
154 struct linflex_serial_priv *priv = dev_get_priv(dev);
155 uint32_t uartsr = __raw_readl(&priv->lfuart->uartsr);
158 return ((uartsr & UARTSR_DRF) && (uartsr & UARTSR_RMB)) ? 1 : 0;
160 return uartsr & UARTSR_DTF ? 0 : 1;
163 static void linflex_serial_init_internal(struct linflex_fsl *lfuart)
165 _linflex_serial_init(lfuart);
166 _linflex_serial_setbrg(lfuart, CONFIG_BAUDRATE);
170 static int linflex_serial_probe(struct udevice *dev)
172 struct linflex_serial_platdata *plat = dev->platdata;
173 struct linflex_serial_priv *priv = dev_get_priv(dev);
175 priv->lfuart = (struct linflex_fsl *)plat->base_addr;
176 linflex_serial_init_internal(priv->lfuart);
181 static const struct dm_serial_ops linflex_serial_ops = {
182 .putc = linflex_serial_putc,
183 .pending = linflex_serial_pending,
184 .getc = linflex_serial_getc,
185 .setbrg = linflex_serial_setbrg,
188 U_BOOT_DRIVER(serial_linflex) = {
189 .name = "serial_linflex",
191 .probe = linflex_serial_probe,
192 .ops = &linflex_serial_ops,
193 .flags = DM_FLAG_PRE_RELOC,
194 .priv_auto_alloc_size = sizeof(struct linflex_serial_priv),
197 #ifdef CONFIG_DEBUG_UART_LINFLEXUART
199 #include <debug_uart.h>
202 static inline void _debug_uart_init(void)
204 struct linflex_fsl *base = (struct linflex_fsl *)CONFIG_DEBUG_UART_BASE;
206 linflex_serial_init_internal(base);
209 static inline void _debug_uart_putc(int ch)
211 struct linflex_fsl *base = (struct linflex_fsl *)CONFIG_DEBUG_UART_BASE;
213 /* XXX: Is this OK? Should this use the non-DM version? */
214 _linflex_serial_putc(base, ch);
219 #endif /* CONFIG_DEBUG_UART_LINFLEXUART */