add early uart driver so we can print debug message in
SPL stage

Signed-off-by: Lin Huang <h...@rock-chips.com>
---
 arch/arm/include/asm/arch-rockchip/uart.h | 39 ++++++++++++++++++++++
 arch/arm/mach-rockchip/Makefile           |  1 +
 arch/arm/mach-rockchip/rk_early_print.c   | 55 +++++++++++++++++++++++++++++++
 3 files changed, 95 insertions(+)
 create mode 100644 arch/arm/include/asm/arch-rockchip/uart.h
 create mode 100644 arch/arm/mach-rockchip/rk_early_print.c

diff --git a/arch/arm/include/asm/arch-rockchip/uart.h 
b/arch/arm/include/asm/arch-rockchip/uart.h
new file mode 100644
index 0000000..db45f9a
--- /dev/null
+++ b/arch/arm/include/asm/arch-rockchip/uart.h
@@ -0,0 +1,39 @@
+#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);
+void print_hex(unsigned int n);
+void print(char *s);
+#endif
+
diff --git a/arch/arm/mach-rockchip/Makefile b/arch/arm/mach-rockchip/Makefile
index 902235b..a29675d 100644
--- a/arch/arm/mach-rockchip/Makefile
+++ b/arch/arm/mach-rockchip/Makefile
@@ -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/
diff --git a/arch/arm/mach-rockchip/rk_early_print.c 
b/arch/arm/mach-rockchip/rk_early_print.c
new file mode 100644
index 0000000..e712016
--- /dev/null
+++ b/arch/arm/mach-rockchip/rk_early_print.c
@@ -0,0 +1,55 @@
+/*
+ * (C) Copyright 2015 Google, Inc
+ *
+ * SPDX-License-Identifier:     GPL-2.0+
+ */
+
+#include <asm/io.h>
+#include <asm/arch/uart.h>
+#include <common.h>
+
+static struct rk_uart * const uart_ptr = (void *)CONFIG_DEBUG_UART_BASE;
+
+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');
+}
+
+void rk_uart_init(void)
+{
+       writel(0x83, &uart_ptr->lcr);
+       writel(0x0d, &uart_ptr->rbr);
+       writel(0x03, &uart_ptr->lcr);
+       writel(0x01, &uart_ptr->sfe);
+}
-- 
1.9.1

_______________________________________________
U-Boot mailing list
U-Boot@lists.denx.de
http://lists.denx.de/mailman/listinfo/u-boot

Reply via email to