From: Stephen Warren swarren@nvidia.com
Currently, SPL console initialization on Tegra suffers from two problems:
1) It's a monolithic function that knows about all possibilities using tables and ifdefs set by board config.h, and contained in core files that are always built into U-Boot. Some of the code can't be ported to future SoCs since the clock APIs will be different. Equally, future SoCs don't need the code since earlier boot FW will always initialized the UART.
2) It's unnecessarily invoked twice, once by SPL and once by the main U-Boot binary.
This patch adds simpler APIs to initialize the UART from SPL. This code can be omitted from non-SPL builds.
A future patch will add the code to the Makefile when board files are converted. Adding it now would cause duplicate symbols for the UART device itself which will cause the link to fail. Even if that were resolved by changing the symbol name, duplicate UART devices would be registered, which would likely cause runtime problems.
Signed-off-by: Stephen Warren swarren@nvidia.com --- arch/arm/mach-tegra/include/mach/spl_uart.h | 20 +++++++++++++++ arch/arm/mach-tegra/spl_uart.c | 39 +++++++++++++++++++++++++++++ 2 files changed, 59 insertions(+) create mode 100644 arch/arm/mach-tegra/include/mach/spl_uart.h create mode 100644 arch/arm/mach-tegra/spl_uart.c
diff --git a/arch/arm/mach-tegra/include/mach/spl_uart.h b/arch/arm/mach-tegra/include/mach/spl_uart.h new file mode 100644 index 000000000000..28b14acce93b --- /dev/null +++ b/arch/arm/mach-tegra/include/mach/spl_uart.h @@ -0,0 +1,20 @@ +/* + * Copyright (c) 2016, NVIDIA CORPORATION. All rights reserved. + * + * SPDX-License-Identifier: GPL-2.0 + */ + +#ifndef _MACH_SPL_UART_H +#define _MACH_SPL_UART_H + +enum tegra_spl_uart { + TEGRA_SPL_UART_A, + TEGRA_SPL_UART_B, + TEGRA_SPL_UART_C, + TEGRA_SPL_UART_D, + TEGRA_SPL_UART_E, +}; + +void tegra_spl_setup_uart(enum tegra_spl_uart uart_id); + +#endif diff --git a/arch/arm/mach-tegra/spl_uart.c b/arch/arm/mach-tegra/spl_uart.c new file mode 100644 index 000000000000..2c1d237174fd --- /dev/null +++ b/arch/arm/mach-tegra/spl_uart.c @@ -0,0 +1,39 @@ +/* + * Copyright (c) 2014-2016, NVIDIA CORPORATION. All rights reserved. + * + * SPDX-License-Identifier: GPL-2.0 + */ + +#include <common.h> +#include <dm.h> +#include <ns16550.h> +#include <asm/arch/clock.h> +#include <mach/spl_uart.h> + +static struct ns16550_platdata ns16550_com1_pdata = { + .reg_shift = 2, + .clock = CONFIG_SYS_NS16550_CLK, +}; + +U_BOOT_DEVICE(ns16550_com1) = { + "ns16550_serial", &ns16550_com1_pdata +}; + +static const struct { + unsigned long addr; + enum periph_id periph_id; +} uart_info[] = { + { NV_PA_APB_UARTA_BASE, PERIPH_ID_UART1, }, + { NV_PA_APB_UARTB_BASE, PERIPH_ID_UART2, }, + { NV_PA_APB_UARTC_BASE, PERIPH_ID_UART3, }, + { NV_PA_APB_UARTD_BASE, PERIPH_ID_UART4, }, + { NV_PA_APB_UARTE_BASE, PERIPH_ID_UART5, }, +}; + +void tegra_spl_setup_uart(unsigned int uart_id) +{ + if (uart_id >= ARRAY_SIZE(uart_info)) + return; + clock_ll_start_uart(uart_info[uart_id].periph_id); + ns16550_com1_pdata.base = uart_info[uart_id].addr; +}