1 // SPDX-License-Identifier: GPL-2.0+
3 * (C) Copyright 2013-2016 Freescale Semiconductor, Inc.
12 #include <linux/compiler.h>
13 #include <asm/arch/imx-regs.h>
14 #include <asm/arch/clock.h>
16 #define US1_TDRE (1 << 7)
17 #define US1_RDRF (1 << 5)
18 #define UC2_TE (1 << 3)
19 #define LINCR1_INIT (1 << 0)
20 #define LINCR1_MME (1 << 4)
21 #define LINCR1_BF (1 << 7)
22 #define LINSR_LINS_INITMODE (0x00001000)
23 #define LINSR_LINS_MASK (0x0000F000)
24 #define UARTCR_UART (1 << 0)
25 #define UARTCR_WL0 (1 << 1)
26 #define UARTCR_PCE (1 << 2)
27 #define UARTCR_PC0 (1 << 3)
28 #define UARTCR_TXEN (1 << 4)
29 #define UARTCR_RXEN (1 << 5)
30 #define UARTCR_PC1 (1 << 6)
31 #define UARTSR_DTF (1 << 1)
32 #define UARTSR_DRF (1 << 2)
33 #define UARTSR_RMB (1 << 9)
35 DECLARE_GLOBAL_DATA_PTR;
37 static void _linflex_serial_setbrg(struct linflex_fsl *base, int baudrate)
39 u32 clk = mxc_get_clock(MXC_UART_CLK);
43 baudrate = CONFIG_BAUDRATE;
45 ibr = (u32) (clk / (16 * gd->baudrate));
46 fbr = (u32) (clk % (16 * gd->baudrate)) * 16;
48 __raw_writel(ibr, &base->linibrr);
49 __raw_writel(fbr, &base->linfbrr);
52 static int _linflex_serial_getc(struct linflex_fsl *base)
56 if (!(__raw_readb(&base->uartsr) & UARTSR_DRF))
59 if (!(__raw_readl(&base->uartsr) & UARTSR_RMB))
62 c = __raw_readl(&base->bdrm);
63 __raw_writeb((__raw_readb(&base->uartsr) | (UARTSR_DRF | UARTSR_RMB)),
68 static int _linflex_serial_putc(struct linflex_fsl *base, const char c)
70 __raw_writeb(c, &base->bdrl);
73 if (!(__raw_readb(&base->uartsr) & UARTSR_DTF))
76 __raw_writeb((__raw_readb(&base->uartsr) | UARTSR_DTF), &base->uartsr);
82 * Initialise the serial port with the given baudrate. The settings
83 * are always 8 data bits, no parity, 1 stop bit, no start bits.
85 static int _linflex_serial_init(struct linflex_fsl *base)
89 /* set the Linflex in master mode amd activate by-pass filter */
90 ctrl = LINCR1_BF | LINCR1_MME;
91 __raw_writel(ctrl, &base->lincr1);
95 __raw_writel(ctrl, &base->lincr1);
97 /* waiting for init mode entry - TODO: add a timeout */
98 while ((__raw_readl(&base->linsr) & LINSR_LINS_MASK) !=
101 /* set UART bit to allow writing other bits */
102 __raw_writel(UARTCR_UART, &base->uartcr);
104 /* provide data bits, parity, stop bit, etc */
107 /* 8 bit data, no parity, Tx and Rx enabled, UART mode */
108 __raw_writel(UARTCR_PC1 | UARTCR_RXEN | UARTCR_TXEN | UARTCR_PC0
109 | UARTCR_WL0 | UARTCR_UART, &base->uartcr);
111 ctrl = __raw_readl(&base->lincr1);
112 ctrl &= ~LINCR1_INIT;
113 __raw_writel(ctrl, &base->lincr1); /* end init mode */
118 struct linflex_serial_platdata {
119 struct linflex_fsl *base_addr;
120 u8 port_id; /* do we need this? */
123 struct linflex_serial_priv {
124 struct linflex_fsl *lfuart;
127 int linflex_serial_setbrg(struct udevice *dev, int baudrate)
129 struct linflex_serial_priv *priv = dev_get_priv(dev);
131 _linflex_serial_setbrg(priv->lfuart, baudrate);
136 static int linflex_serial_getc(struct udevice *dev)
138 struct linflex_serial_priv *priv = dev_get_priv(dev);
140 return _linflex_serial_getc(priv->lfuart);
143 static int linflex_serial_putc(struct udevice *dev, const char ch)
146 struct linflex_serial_priv *priv = dev_get_priv(dev);
148 return _linflex_serial_putc(priv->lfuart, ch);
151 static int linflex_serial_pending(struct udevice *dev, bool input)
153 struct linflex_serial_priv *priv = dev_get_priv(dev);
154 uint32_t uartsr = __raw_readl(&priv->lfuart->uartsr);
157 return ((uartsr & UARTSR_DRF) && (uartsr & UARTSR_RMB)) ? 1 : 0;
159 return uartsr & UARTSR_DTF ? 0 : 1;
162 static void linflex_serial_init_internal(struct linflex_fsl *lfuart)
164 _linflex_serial_init(lfuart);
165 _linflex_serial_setbrg(lfuart, CONFIG_BAUDRATE);
169 static int linflex_serial_probe(struct udevice *dev)
171 struct linflex_serial_platdata *plat = dev->platdata;
172 struct linflex_serial_priv *priv = dev_get_priv(dev);
174 priv->lfuart = (struct linflex_fsl *)plat->base_addr;
175 linflex_serial_init_internal(priv->lfuart);
180 static const struct dm_serial_ops linflex_serial_ops = {
181 .putc = linflex_serial_putc,
182 .pending = linflex_serial_pending,
183 .getc = linflex_serial_getc,
184 .setbrg = linflex_serial_setbrg,
187 U_BOOT_DRIVER(serial_linflex) = {
188 .name = "serial_linflex",
190 .probe = linflex_serial_probe,
191 .ops = &linflex_serial_ops,
192 .flags = DM_FLAG_PRE_RELOC,
193 .priv_auto_alloc_size = sizeof(struct linflex_serial_priv),
196 #ifdef CONFIG_DEBUG_UART_LINFLEXUART
198 #include <debug_uart.h>
201 static inline void _debug_uart_init(void)
203 struct linflex_fsl *base = (struct linflex_fsl *)CONFIG_DEBUG_UART_BASE;
205 linflex_serial_init_internal(base);
208 static inline void _debug_uart_putc(int ch)
210 struct linflex_fsl *base = (struct linflex_fsl *)CONFIG_DEBUG_UART_BASE;
212 /* XXX: Is this OK? Should this use the non-DM version? */
213 _linflex_serial_putc(base, ch);
218 #endif /* CONFIG_DEBUG_UART_LINFLEXUART */