The Xilinx 16550 uart core is not a standard 16550 because it uses word-based addressing rather than byte-based adressing. With additional properties it is compatible with the open firmware 'ns16550' compatible binding. This code updates the ns16550 driver to use the reg-offset property so that the Xilinx UART 16550 can be used with it. The reg-shift was already being handled. Signed-off-by: John Linn <john.linn@xilinx.com> Acked-by: Grant Likely <grant.likely@secretlab.ca> Signed-off-by: Josh Boyer <jwboyer@linux.vnet.ibm.com>
		
			
				
	
	
		
			78 lines
		
	
	
	
		
			1.9 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			78 lines
		
	
	
	
		
			1.9 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
/*
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 * 16550 serial console support.
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 *
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 * Original copied from <file:arch/ppc/boot/common/ns16550.c>
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 * (which had no copyright)
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 * Modifications: 2006 (c) MontaVista Software, Inc.
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 *
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 * Modified by: Mark A. Greer <mgreer@mvista.com>
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 */
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#include <stdarg.h>
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#include <stddef.h>
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#include "types.h"
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#include "string.h"
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#include "stdio.h"
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#include "io.h"
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#include "ops.h"
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#define UART_DLL	0	/* Out: Divisor Latch Low */
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#define UART_DLM	1	/* Out: Divisor Latch High */
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#define UART_FCR	2	/* Out: FIFO Control Register */
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#define UART_LCR	3	/* Out: Line Control Register */
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#define UART_MCR	4	/* Out: Modem Control Register */
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#define UART_LSR	5	/* In:  Line Status Register */
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#define UART_LSR_THRE	0x20	/* Transmit-hold-register empty */
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#define UART_LSR_DR	0x01	/* Receiver data ready */
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#define UART_MSR	6	/* In:  Modem Status Register */
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#define UART_SCR	7	/* I/O: Scratch Register */
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static unsigned char *reg_base;
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static u32 reg_shift;
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static int ns16550_open(void)
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{
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	out_8(reg_base + (UART_FCR << reg_shift), 0x06);
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	return 0;
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}
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static void ns16550_putc(unsigned char c)
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{
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	while ((in_8(reg_base + (UART_LSR << reg_shift)) & UART_LSR_THRE) == 0);
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	out_8(reg_base, c);
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}
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static unsigned char ns16550_getc(void)
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{
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	while ((in_8(reg_base + (UART_LSR << reg_shift)) & UART_LSR_DR) == 0);
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	return in_8(reg_base);
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}
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static u8 ns16550_tstc(void)
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{
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	return ((in_8(reg_base + (UART_LSR << reg_shift)) & UART_LSR_DR) != 0);
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}
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int ns16550_console_init(void *devp, struct serial_console_data *scdp)
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{
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	int n;
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	u32 reg_offset;
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	if (dt_get_virtual_reg(devp, (void **)®_base, 1) < 1)
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		return -1;
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	n = getprop(devp, "reg-offset", ®_offset, sizeof(reg_offset));
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	if (n == sizeof(reg_offset))
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		reg_base += reg_offset;
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	n = getprop(devp, "reg-shift", ®_shift, sizeof(reg_shift));
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	if (n != sizeof(reg_shift))
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		reg_shift = 0;
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	scdp->open = ns16550_open;
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	scdp->putc = ns16550_putc;
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	scdp->getc = ns16550_getc;
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	scdp->tstc = ns16550_tstc;
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	scdp->close = NULL;
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	return 0;
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}
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