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author | huang lin <hl@rock-chips.com> | 2015-11-17 14:20:25 +0800 |
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committer | Simon Glass <sjg@chromium.org> | 2015-12-01 08:07:22 -0700 |
commit | 07d8d35a612b30e37256179fc6fd40158bcb528e (patch) | |
tree | fb247c1bfd8287336b504ee7616038ca7c19994e /arch/arm/mach-rockchip/rk_early_print.c | |
parent | 2863724831a37b7ef84ba7490c4d41e678191b03 (diff) | |
download | u-boot-imx-07d8d35a612b30e37256179fc6fd40158bcb528e.zip u-boot-imx-07d8d35a612b30e37256179fc6fd40158bcb528e.tar.gz u-boot-imx-07d8d35a612b30e37256179fc6fd40158bcb528e.tar.bz2 |
rockchip: add early uart driver
add early uart driver so we can print debug message in
SPL stage
Signed-off-by: Lin Huang <hl@rock-chips.com>
Acked-by: Simon Glass <sjg@chromium.org>
Diffstat (limited to 'arch/arm/mach-rockchip/rk_early_print.c')
-rw-r--r-- | arch/arm/mach-rockchip/rk_early_print.c | 63 |
1 files changed, 63 insertions, 0 deletions
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..a1c14b0 --- /dev/null +++ b/arch/arm/mach-rockchip/rk_early_print.c @@ -0,0 +1,63 @@ +/* + * (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); +} |