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Release 4.14 arch/mips/pic32/pic32mzda/early_console.c

/*
 * Joshua Henderson <joshua.henderson@microchip.com>
 * Copyright (C) 2015 Microchip Technology Inc.  All rights reserved.
 *
 *  This program is free software; you can distribute it and/or modify it
 *  under the terms of the GNU General Public License (Version 2) as
 *  published by the Free Software Foundation.
 *
 *  This program is distributed in the hope it will be useful, but WITHOUT
 *  ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 *  FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 *  for more details.
 */
#include <asm/mach-pic32/pic32.h>
#include <asm/fw/fw.h>

#include "pic32mzda.h"
#include "early_pin.h"

/* Default early console parameters */

#define EARLY_CONSOLE_PORT	1

#define EARLY_CONSOLE_BAUDRATE	115200


#define UART_ENABLE		BIT(15)

#define UART_ENABLE_RX		BIT(12)

#define UART_ENABLE_TX		BIT(10)

#define UART_TX_FULL		BIT(9)

/* UART1(x == 0) - UART6(x == 5) */

#define UART_BASE(x)	((x) * 0x0200)

#define U_MODE(x)	UART_BASE(x)

#define U_STA(x)	(UART_BASE(x) + 0x10)

#define U_TXR(x)	(UART_BASE(x) + 0x20)

#define U_BRG(x)	(UART_BASE(x) + 0x40)


static void __iomem *uart_base;

static char console_port = -1;


static int __init configure_uart_pins(int port) { switch (port) { case 1: pic32_pps_input(IN_FUNC_U2RX, IN_RPB0); pic32_pps_output(OUT_FUNC_U2TX, OUT_RPG9); break; case 5: pic32_pps_input(IN_FUNC_U6RX, IN_RPD0); pic32_pps_output(OUT_FUNC_U6TX, OUT_RPB8); break; default: return -1; } return 0; }

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static void __init configure_uart(char port, int baud) { u32 pbclk; pbclk = pic32_get_pbclk(2); __raw_writel(0, uart_base + U_MODE(port)); __raw_writel(((pbclk / baud) / 16) - 1, uart_base + U_BRG(port)); __raw_writel(UART_ENABLE, uart_base + U_MODE(port)); __raw_writel(UART_ENABLE_TX | UART_ENABLE_RX, uart_base + PIC32_SET(U_STA(port))); }

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Joshua Henderson86100.00%1100.00%
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static void __init setup_early_console(char port, int baud) { if (configure_uart_pins(port)) return; console_port = port; configure_uart(console_port, baud); }

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Joshua Henderson32100.00%1100.00%
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static char * __init pic32_getcmdline(void) { /* * arch_mem_init() has not been called yet, so we don't have a real * command line setup if using CONFIG_CMDLINE_BOOL. */ #ifdef CONFIG_CMDLINE_OVERRIDE return CONFIG_CMDLINE; #else return fw_getcmdline(); #endif }

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static int __init get_port_from_cmdline(char *arch_cmdline) { char *s; int port = -1; if (!arch_cmdline || *arch_cmdline == '\0') goto _out; s = strstr(arch_cmdline, "earlyprintk="); if (s) { s = strstr(s, "ttyS"); if (s) s += 4; else goto _out; port = (*s) - '0'; } _out: return port; }

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static int __init get_baud_from_cmdline(char *arch_cmdline) { char *s; int baud = -1; if (!arch_cmdline || *arch_cmdline == '\0') goto _out; s = strstr(arch_cmdline, "earlyprintk="); if (s) { s = strstr(s, "ttyS"); if (s) s += 6; else goto _out; baud = 0; while (*s >= '0' && *s <= '9') baud = baud * 10 + *s++ - '0'; } _out: return baud; }

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Joshua Henderson103100.00%1100.00%
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void __init fw_init_early_console(char port) { char *arch_cmdline = pic32_getcmdline(); int baud = -1; uart_base = ioremap_nocache(PIC32_BASE_UART, 0xc00); baud = get_baud_from_cmdline(arch_cmdline); if (port == -1) port = get_port_from_cmdline(arch_cmdline); if (port == -1) port = EARLY_CONSOLE_PORT; if (baud == -1) baud = EARLY_CONSOLE_BAUDRATE; setup_early_console(port, baud); }

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int prom_putchar(char c) { if (console_port >= 0) { while (__raw_readl( uart_base + U_STA(console_port)) & UART_TX_FULL) ; __raw_writel(c, uart_base + U_TXR(console_port)); } return 1; }

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Joshua Henderson46100.00%1100.00%
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Joshua Henderson604100.00%1100.00%
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