Commit 07d8d35a authored by huang lin's avatar huang lin Committed by Simon Glass
Browse files

rockchip: add early uart driver



add early uart driver so we can print debug message in
SPL stage
Signed-off-by: default avatarLin Huang <hl@rock-chips.com>
Acked-by: Simon Glass's avatarSimon Glass <sjg@chromium.org>
parent 28637248
/*
* (C) Copyright 2015 Rockchip Electronics Co., Ltd
*
* SPDX-License-Identifier: GPL-2.0+
*/
#ifndef __ASM_ARCH_UART_H
#define __ASM_ARCH_UART_H
struct rk_uart {
unsigned int rbr; /* Receive buffer register. */
unsigned int ier; /* Interrupt enable register. */
unsigned int fcr; /* FIFO control register. */
unsigned int lcr; /* Line control register. */
unsigned int mcr; /* Modem control register. */
unsigned int lsr; /* Line status register. */
unsigned int msr; /* Modem status register. */
unsigned int scr;
unsigned int reserved1[(0x30 - 0x20) / 4];
unsigned int srbr[(0x70 - 0x30) / 4];
unsigned int far;
unsigned int tfr;
unsigned int rfw;
unsigned int usr;
unsigned int tfl;
unsigned int rfl;
unsigned int srr;
unsigned int srts;
unsigned int sbcr;
unsigned int sdmam;
unsigned int sfe;
unsigned int srt;
unsigned int stet;
unsigned int htx;
unsigned int dmasa;
unsigned int reserver2[(0xf4 - 0xac) / 4];
unsigned int cpr;
unsigned int ucv;
unsigned int ctr;
};
void rk_uart_init(void *base);
void print_hex(unsigned int n);
void print(char *s);
#endif
......@@ -10,5 +10,6 @@ else
obj-y += board.o
endif
obj-y += rk_timer.o
obj-y += rk_early_print.o
obj-$(CONFIG_$(SPL_)ROCKCHIP_COMMON) += common.o
obj-$(CONFIG_ROCKCHIP_RK3288) += rk3288/
/*
* (C) Copyright 2015 Rockchip Electronics Co., Ltd
*
* SPDX-License-Identifier: GPL-2.0+
*/
#include <asm/io.h>
#include <asm/arch/uart.h>
#include <common.h>
static struct rk_uart *uart_ptr;
static void uart_wrtie_byte(char byte)
{
writel(byte, &uart_ptr->rbr);
while (!(readl(&uart_ptr->lsr) & 0x40))
;
}
void print(char *s)
{
while (*s) {
if (*s == '\n')
uart_wrtie_byte('\r');
uart_wrtie_byte(*s);
s++;
}
}
void print_hex(unsigned int n)
{
int i;
int temp;
uart_wrtie_byte('0');
uart_wrtie_byte('x');
for (i = 8; i > 0; i--) {
temp = (n >> (i - 1) * 4) & 0x0f;
if (temp < 10)
uart_wrtie_byte((char)(temp + '0'));
else
uart_wrtie_byte((char)(temp - 10 + 'a'));
}
uart_wrtie_byte('\n');
uart_wrtie_byte('\r');
}
/*
* TODO: since rk3036 only 4K sram to use in SPL, for saving space,
* we implement uart driver this way, we should convert this to use
* ns16550 driver in future, which support DEBUG_UART in the standard way
*/
void rk_uart_init(void *base)
{
uart_ptr = (struct rk_uart *)base;
writel(0x83, &uart_ptr->lcr);
writel(0x0d, &uart_ptr->rbr);
writel(0x03, &uart_ptr->lcr);
/* fifo enable, sfe is shadow register of FCR[0] */
writel(0x01, &uart_ptr->sfe);
}
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