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da0a5f0c65
This patch adds a new generic device tree processing function that retrieves virtual reg addresses from the device tree to the bootwrapper code. It also updates the bootwrapper code to use the new function. dt_get_virtual_reg() retrieves the virtual reg addresses from the "virtual-reg" property. If the property can't be found, it uses the "reg" property and walks the tree to translate it to absolute addresses. Signed-off-by: Laurent Pinchart <laurentp@cse-semaphore.com> Acked-by: Scott Wood <scottwood@freescale.com> Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
74 lines
1.8 KiB
C
74 lines
1.8 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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if (dt_get_virtual_reg(devp, (void **)®_base, 1) < 1)
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return -1;
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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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