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	Allow the ns16550 debug UART to be used without the full driver. Signed-off-by: Simon Glass <sjg@chromium.org> Reviewed-by: Thomas Chou <thomas@wytron.com.tw>
		
			
				
	
	
		
			458 lines
		
	
	
		
			12 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			458 lines
		
	
	
		
			12 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /*
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|  * COM1 NS16550 support
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|  * originally from linux source (arch/powerpc/boot/ns16550.c)
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|  * modified to use CONFIG_SYS_ISA_MEM and new defines
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|  */
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| 
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| #include <common.h>
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| #include <dm.h>
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| #include <errno.h>
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| #include <fdtdec.h>
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| #include <ns16550.h>
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| #include <serial.h>
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| #include <watchdog.h>
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| #include <linux/types.h>
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| #include <asm/io.h>
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| 
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| DECLARE_GLOBAL_DATA_PTR;
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| 
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| #define UART_LCRVAL UART_LCR_8N1		/* 8 data, 1 stop, no parity */
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| #define UART_MCRVAL (UART_MCR_DTR | \
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| 		     UART_MCR_RTS)		/* RTS/DTR */
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| #define UART_FCRVAL (UART_FCR_FIFO_EN |	\
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| 		     UART_FCR_RXSR |	\
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| 		     UART_FCR_TXSR)		/* Clear & enable FIFOs */
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| 
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| #ifndef CONFIG_DM_SERIAL
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| #ifdef CONFIG_SYS_NS16550_PORT_MAPPED
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| #define serial_out(x, y)	outb(x, (ulong)y)
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| #define serial_in(y)		inb((ulong)y)
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| #elif defined(CONFIG_SYS_NS16550_MEM32) && (CONFIG_SYS_NS16550_REG_SIZE > 0)
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| #define serial_out(x, y)	out_be32(y, x)
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| #define serial_in(y)		in_be32(y)
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| #elif defined(CONFIG_SYS_NS16550_MEM32) && (CONFIG_SYS_NS16550_REG_SIZE < 0)
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| #define serial_out(x, y)	out_le32(y, x)
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| #define serial_in(y)		in_le32(y)
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| #else
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| #define serial_out(x, y)	writeb(x, y)
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| #define serial_in(y)		readb(y)
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| #endif
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| #endif /* !CONFIG_DM_SERIAL */
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| 
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| #if defined(CONFIG_SOC_KEYSTONE)
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| #define UART_REG_VAL_PWREMU_MGMT_UART_DISABLE   0
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| #define UART_REG_VAL_PWREMU_MGMT_UART_ENABLE ((1 << 14) | (1 << 13) | (1 << 0))
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| #undef UART_MCRVAL
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| #ifdef CONFIG_SERIAL_HW_FLOW_CONTROL
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| #define UART_MCRVAL             (UART_MCR_RTS | UART_MCR_AFE)
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| #else
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| #define UART_MCRVAL             (UART_MCR_RTS)
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| #endif
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| #endif
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| 
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| #ifndef CONFIG_SYS_NS16550_IER
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| #define CONFIG_SYS_NS16550_IER  0x00
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| #endif /* CONFIG_SYS_NS16550_IER */
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| 
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| #ifdef CONFIG_DM_SERIAL
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| 
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| #ifndef CONFIG_SYS_NS16550_CLK
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| #define CONFIG_SYS_NS16550_CLK  0
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| #endif
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| 
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| static inline void serial_out_shift(void *addr, int shift, int value)
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| {
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| #ifdef CONFIG_SYS_NS16550_PORT_MAPPED
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| 	outb(value, (ulong)addr);
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| #elif defined(CONFIG_SYS_NS16550_MEM32) && !defined(CONFIG_SYS_BIG_ENDIAN)
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| 	out_le32(addr, value);
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| #elif defined(CONFIG_SYS_NS16550_MEM32) && defined(CONFIG_SYS_BIG_ENDIAN)
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| 	out_be32(addr, value);
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| #elif defined(CONFIG_SYS_NS16550_MEM32)
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| 	writel(value, addr);
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| #elif defined(CONFIG_SYS_BIG_ENDIAN)
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| 	writeb(value, addr + (1 << shift) - 1);
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| #else
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| 	writeb(value, addr);
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| #endif
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| }
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| 
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| static inline int serial_in_shift(void *addr, int shift)
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| {
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| #ifdef CONFIG_SYS_NS16550_PORT_MAPPED
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| 	return inb((ulong)addr);
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| #elif defined(CONFIG_SYS_NS16550_MEM32) && !defined(CONFIG_SYS_BIG_ENDIAN)
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| 	return in_le32(addr);
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| #elif defined(CONFIG_SYS_NS16550_MEM32) && defined(CONFIG_SYS_BIG_ENDIAN)
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| 	return in_be32(addr);
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| #elif defined(CONFIG_SYS_NS16550_MEM32)
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| 	return readl(addr);
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| #elif defined(CONFIG_SYS_BIG_ENDIAN)
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| 	return readb(addr + (1 << shift) - 1);
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| #else
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| 	return readb(addr);
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| #endif
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| }
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| 
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| static void ns16550_writeb(NS16550_t port, int offset, int value)
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| {
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| 	struct ns16550_platdata *plat = port->plat;
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| 	unsigned char *addr;
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| 
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| 	offset *= 1 << plat->reg_shift;
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| 	addr = map_physmem(plat->base, 0, MAP_NOCACHE) + offset;
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| 	/*
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| 	 * As far as we know it doesn't make sense to support selection of
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| 	 * these options at run-time, so use the existing CONFIG options.
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| 	 */
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| 	serial_out_shift(addr, plat->reg_shift, value);
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| }
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| 
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| static int ns16550_readb(NS16550_t port, int offset)
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| {
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| 	struct ns16550_platdata *plat = port->plat;
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| 	unsigned char *addr;
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| 
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| 	offset *= 1 << plat->reg_shift;
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| 	addr = map_physmem(plat->base, 0, MAP_NOCACHE) + offset;
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| 
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| 	return serial_in_shift(addr, plat->reg_shift);
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| }
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| 
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| /* We can clean these up once everything is moved to driver model */
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| #define serial_out(value, addr)	\
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| 	ns16550_writeb(com_port, \
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| 		(unsigned char *)addr - (unsigned char *)com_port, value)
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| #define serial_in(addr) \
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| 	ns16550_readb(com_port, \
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| 		(unsigned char *)addr - (unsigned char *)com_port)
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| #endif
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| 
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| static inline int calc_divisor(NS16550_t port, int clock, int baudrate)
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| {
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| 	const unsigned int mode_x_div = 16;
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| 
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| 	return DIV_ROUND_CLOSEST(clock, mode_x_div * baudrate);
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| }
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| 
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| int ns16550_calc_divisor(NS16550_t port, int clock, int baudrate)
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| {
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| #ifdef CONFIG_OMAP1510
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| 	/* If can't cleanly clock 115200 set div to 1 */
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| 	if ((clock == 12000000) && (baudrate == 115200)) {
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| 		port->osc_12m_sel = OSC_12M_SEL;  /* enable 6.5 * divisor */
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| 		return 1;			/* return 1 for base divisor */
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| 	}
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| 	port->osc_12m_sel = 0;			/* clear if previsouly set */
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| #endif
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| 
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| 	return calc_divisor(port, clock, baudrate);
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| }
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| 
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| static void NS16550_setbrg(NS16550_t com_port, int baud_divisor)
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| {
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| 	serial_out(UART_LCR_BKSE | UART_LCRVAL, &com_port->lcr);
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| 	serial_out(baud_divisor & 0xff, &com_port->dll);
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| 	serial_out((baud_divisor >> 8) & 0xff, &com_port->dlm);
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| 	serial_out(UART_LCRVAL, &com_port->lcr);
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| }
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| 
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| void NS16550_init(NS16550_t com_port, int baud_divisor)
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| {
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| #if (defined(CONFIG_SPL_BUILD) && \
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| 		(defined(CONFIG_OMAP34XX) || defined(CONFIG_OMAP44XX)))
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| 	/*
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| 	 * On some OMAP3/OMAP4 devices when UART3 is configured for boot mode
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| 	 * before SPL starts only THRE bit is set. We have to empty the
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| 	 * transmitter before initialization starts.
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| 	 */
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| 	if ((serial_in(&com_port->lsr) & (UART_LSR_TEMT | UART_LSR_THRE))
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| 	     == UART_LSR_THRE) {
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| 		if (baud_divisor != -1)
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| 			NS16550_setbrg(com_port, baud_divisor);
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| 		serial_out(0, &com_port->mdr1);
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| 	}
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| #endif
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| 
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| 	while (!(serial_in(&com_port->lsr) & UART_LSR_TEMT))
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| 		;
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| 
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| 	serial_out(CONFIG_SYS_NS16550_IER, &com_port->ier);
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| #if defined(CONFIG_OMAP) || defined(CONFIG_AM33XX) || \
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| 			defined(CONFIG_TI81XX) || defined(CONFIG_AM43XX)
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| 	serial_out(0x7, &com_port->mdr1);	/* mode select reset TL16C750*/
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| #endif
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| 	serial_out(UART_MCRVAL, &com_port->mcr);
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| 	serial_out(UART_FCRVAL, &com_port->fcr);
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| 	if (baud_divisor != -1)
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| 		NS16550_setbrg(com_port, baud_divisor);
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| #if defined(CONFIG_OMAP) || \
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| 	defined(CONFIG_AM33XX) || defined(CONFIG_SOC_DA8XX) || \
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| 	defined(CONFIG_TI81XX) || defined(CONFIG_AM43XX)
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| 
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| 	/* /16 is proper to hit 115200 with 48MHz */
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| 	serial_out(0, &com_port->mdr1);
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| #endif /* CONFIG_OMAP */
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| #if defined(CONFIG_SOC_KEYSTONE)
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| 	serial_out(UART_REG_VAL_PWREMU_MGMT_UART_ENABLE, &com_port->regC);
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| #endif
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| }
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| 
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| #ifndef CONFIG_NS16550_MIN_FUNCTIONS
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| void NS16550_reinit(NS16550_t com_port, int baud_divisor)
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| {
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| 	serial_out(CONFIG_SYS_NS16550_IER, &com_port->ier);
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| 	NS16550_setbrg(com_port, 0);
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| 	serial_out(UART_MCRVAL, &com_port->mcr);
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| 	serial_out(UART_FCRVAL, &com_port->fcr);
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| 	NS16550_setbrg(com_port, baud_divisor);
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| }
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| #endif /* CONFIG_NS16550_MIN_FUNCTIONS */
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| 
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| void NS16550_putc(NS16550_t com_port, char c)
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| {
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| 	while ((serial_in(&com_port->lsr) & UART_LSR_THRE) == 0)
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| 		;
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| 	serial_out(c, &com_port->thr);
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| 
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| 	/*
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| 	 * Call watchdog_reset() upon newline. This is done here in putc
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| 	 * since the environment code uses a single puts() to print the complete
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| 	 * environment upon "printenv". So we can't put this watchdog call
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| 	 * in puts().
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| 	 */
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| 	if (c == '\n')
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| 		WATCHDOG_RESET();
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| }
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| 
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| #ifndef CONFIG_NS16550_MIN_FUNCTIONS
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| char NS16550_getc(NS16550_t com_port)
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| {
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| 	while ((serial_in(&com_port->lsr) & UART_LSR_DR) == 0) {
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| #if !defined(CONFIG_SPL_BUILD) && defined(CONFIG_USB_TTY)
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| 		extern void usbtty_poll(void);
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| 		usbtty_poll();
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| #endif
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| 		WATCHDOG_RESET();
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| 	}
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| 	return serial_in(&com_port->rbr);
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| }
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| 
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| int NS16550_tstc(NS16550_t com_port)
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| {
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| 	return (serial_in(&com_port->lsr) & UART_LSR_DR) != 0;
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| }
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| 
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| #endif /* CONFIG_NS16550_MIN_FUNCTIONS */
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| 
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| #ifdef CONFIG_DEBUG_UART_NS16550
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| 
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| #include <debug_uart.h>
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| 
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| #define serial_dout(reg, value)	\
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| 	serial_out_shift((char *)com_port + \
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| 		((char *)reg - (char *)com_port) * \
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| 			(1 << CONFIG_DEBUG_UART_SHIFT), \
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| 		CONFIG_DEBUG_UART_SHIFT, value)
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| #define serial_din(reg) \
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| 	serial_in_shift((char *)com_port + \
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| 		((char *)reg - (char *)com_port) * \
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| 			(1 << CONFIG_DEBUG_UART_SHIFT), \
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| 		CONFIG_DEBUG_UART_SHIFT)
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| 
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| static inline void _debug_uart_init(void)
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| {
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| 	struct NS16550 *com_port = (struct NS16550 *)CONFIG_DEBUG_UART_BASE;
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| 	int baud_divisor;
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| 
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| 	/*
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| 	 * We copy the code from above because it is already horribly messy.
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| 	 * Trying to refactor to nicely remove the duplication doesn't seem
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| 	 * feasible. The better fix is to move all users of this driver to
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| 	 * driver model.
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| 	 */
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| 	baud_divisor = calc_divisor(com_port, CONFIG_DEBUG_UART_CLOCK,
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| 				    CONFIG_BAUDRATE);
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| 	serial_dout(&com_port->ier, CONFIG_SYS_NS16550_IER);
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| 	serial_dout(&com_port->mcr, UART_MCRVAL);
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| 	serial_dout(&com_port->fcr, UART_FCRVAL);
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| 
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| 	serial_dout(&com_port->lcr, UART_LCR_BKSE | UART_LCRVAL);
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| 	serial_dout(&com_port->dll, baud_divisor & 0xff);
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| 	serial_dout(&com_port->dlm, (baud_divisor >> 8) & 0xff);
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| 	serial_dout(&com_port->lcr, UART_LCRVAL);
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| }
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| 
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| static inline void _debug_uart_putc(int ch)
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| {
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| 	struct NS16550 *com_port = (struct NS16550 *)CONFIG_DEBUG_UART_BASE;
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| 
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| 	while (!(serial_din(&com_port->lsr) & UART_LSR_THRE))
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| 		;
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| 	serial_dout(&com_port->thr, ch);
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| }
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| 
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| DEBUG_UART_FUNCS
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| 
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| #endif
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| 
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| #ifdef CONFIG_DM_SERIAL
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| static int ns16550_serial_putc(struct udevice *dev, const char ch)
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| {
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| 	struct NS16550 *const com_port = dev_get_priv(dev);
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| 
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| 	if (!(serial_in(&com_port->lsr) & UART_LSR_THRE))
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| 		return -EAGAIN;
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| 	serial_out(ch, &com_port->thr);
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| 
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| 	/*
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| 	 * Call watchdog_reset() upon newline. This is done here in putc
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| 	 * since the environment code uses a single puts() to print the complete
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| 	 * environment upon "printenv". So we can't put this watchdog call
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| 	 * in puts().
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| 	 */
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| 	if (ch == '\n')
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| 		WATCHDOG_RESET();
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| 
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| 	return 0;
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| }
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| 
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| static int ns16550_serial_pending(struct udevice *dev, bool input)
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| {
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| 	struct NS16550 *const com_port = dev_get_priv(dev);
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| 
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| 	if (input)
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| 		return serial_in(&com_port->lsr) & UART_LSR_DR ? 1 : 0;
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| 	else
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| 		return serial_in(&com_port->lsr) & UART_LSR_THRE ? 0 : 1;
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| }
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| 
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| static int ns16550_serial_getc(struct udevice *dev)
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| {
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| 	struct NS16550 *const com_port = dev_get_priv(dev);
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| 
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| 	if (!(serial_in(&com_port->lsr) & UART_LSR_DR))
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| 		return -EAGAIN;
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| 
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| 	return serial_in(&com_port->rbr);
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| }
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| 
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| static int ns16550_serial_setbrg(struct udevice *dev, int baudrate)
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| {
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| 	struct NS16550 *const com_port = dev_get_priv(dev);
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| 	struct ns16550_platdata *plat = com_port->plat;
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| 	int clock_divisor;
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| 
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| 	clock_divisor = ns16550_calc_divisor(com_port, plat->clock, baudrate);
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| 
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| 	NS16550_setbrg(com_port, clock_divisor);
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| 
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| 	return 0;
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| }
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| 
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| int ns16550_serial_probe(struct udevice *dev)
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| {
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| 	struct NS16550 *const com_port = dev_get_priv(dev);
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| 
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| 	com_port->plat = dev_get_platdata(dev);
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| 	NS16550_init(com_port, -1);
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| 
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| 	return 0;
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| }
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| 
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| #if CONFIG_IS_ENABLED(OF_CONTROL)
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| int ns16550_serial_ofdata_to_platdata(struct udevice *dev)
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| {
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| 	struct ns16550_platdata *plat = dev->platdata;
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| 	fdt_addr_t addr;
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| 
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| 	/* try Processor Local Bus device first */
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| 	addr = dev_get_addr(dev);
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| #if defined(CONFIG_PCI) && defined(CONFIG_DM_PCI)
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| 	if (addr == FDT_ADDR_T_NONE) {
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| 		/* then try pci device */
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| 		struct fdt_pci_addr pci_addr;
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| 		u32 bar;
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| 		int ret;
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| 
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| 		/* we prefer to use a memory-mapped register */
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| 		ret = fdtdec_get_pci_addr(gd->fdt_blob, dev->of_offset,
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| 					  FDT_PCI_SPACE_MEM32, "reg",
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| 					  &pci_addr);
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| 		if (ret) {
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| 			/* try if there is any i/o-mapped register */
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| 			ret = fdtdec_get_pci_addr(gd->fdt_blob,
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| 						  dev->of_offset,
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| 						  FDT_PCI_SPACE_IO,
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| 						  "reg", &pci_addr);
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| 			if (ret)
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| 				return ret;
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| 		}
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| 
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| 		ret = fdtdec_get_pci_bar32(dev, &pci_addr, &bar);
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| 		if (ret)
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| 			return ret;
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| 
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| 		addr = bar;
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| 	}
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| #endif
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| 
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| 	if (addr == FDT_ADDR_T_NONE)
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| 		return -EINVAL;
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| 
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| 	plat->base = addr;
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| 	plat->reg_shift = fdtdec_get_int(gd->fdt_blob, dev->of_offset,
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| 					 "reg-shift", 0);
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| 	plat->clock = fdtdec_get_int(gd->fdt_blob, dev->of_offset,
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| 				     "clock-frequency",
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| 				     CONFIG_SYS_NS16550_CLK);
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| 	if (!plat->clock) {
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| 		debug("ns16550 clock not defined\n");
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| 		return -EINVAL;
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| 	}
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| 
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| 	return 0;
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| }
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| #endif
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| 
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| const struct dm_serial_ops ns16550_serial_ops = {
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| 	.putc = ns16550_serial_putc,
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| 	.pending = ns16550_serial_pending,
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| 	.getc = ns16550_serial_getc,
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| 	.setbrg = ns16550_serial_setbrg,
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| };
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| 
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| #if CONFIG_IS_ENABLED(OF_CONTROL)
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| static const struct udevice_id ns16550_serial_ids[] = {
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| 	{ .compatible = "ns16550" },
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| 	{ .compatible = "ns16550a" },
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| 	{ .compatible = "nvidia,tegra20-uart" },
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| 	{ .compatible = "rockchip,rk3036-uart" },
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| 	{ .compatible = "snps,dw-apb-uart" },
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| 	{ .compatible = "ti,omap2-uart" },
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| 	{ .compatible = "ti,omap3-uart" },
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| 	{ .compatible = "ti,omap4-uart" },
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| 	{ .compatible = "ti,am3352-uart" },
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| 	{ .compatible = "ti,am4372-uart" },
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| 	{ .compatible = "ti,dra742-uart" },
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| 	{}
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| };
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| #endif
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| 
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| #if CONFIG_IS_ENABLED(SERIAL_PRESENT)
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| U_BOOT_DRIVER(ns16550_serial) = {
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| 	.name	= "ns16550_serial",
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| 	.id	= UCLASS_SERIAL,
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| #if CONFIG_IS_ENABLED(OF_CONTROL)
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| 	.of_match = ns16550_serial_ids,
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| 	.ofdata_to_platdata = ns16550_serial_ofdata_to_platdata,
 | |
| 	.platdata_auto_alloc_size = sizeof(struct ns16550_platdata),
 | |
| #endif
 | |
| 	.priv_auto_alloc_size = sizeof(struct NS16550),
 | |
| 	.probe = ns16550_serial_probe,
 | |
| 	.ops	= &ns16550_serial_ops,
 | |
| 	.flags	= DM_FLAG_PRE_RELOC,
 | |
| };
 | |
| #endif
 | |
| #endif /* CONFIG_DM_SERIAL */
 |