[mirror_ubuntu-jammy-kernel.git] / arch / mips / pic32 / pic32mzda / early_console.c

// SPDX-License-Identifier: GPL-2.0-only
/*
 * Joshua Henderson <joshua.henderson@microchip.com>
 * Copyright (C) 2015 Microchip Technology Inc.  All rights reserved.
 */
#include <asm/mach-pic32/pic32.h>
#include <asm/fw/fw.h>
#include <asm/setup.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;
}

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)));
}

static void __init setup_early_console(char port, int baud)
{
	if (configure_uart_pins(port))
		return;

	console_port = port;
	configure_uart(console_port, baud);
}

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
}

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;
}

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;
}

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);
}

void 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));
	}
}
Commit	Line	Data
04dc82e1	1	// SPDX-License-Identifier: GPL-2.0-only
2572f00d JH	2	/*
	3	* Joshua Henderson <joshua.henderson@microchip.com>
	4	* Copyright (C) 2015 Microchip Technology Inc. All rights reserved.
2572f00d JH	5	*/
	6	#include <asm/mach-pic32/pic32.h>
	7	#include <asm/fw/fw.h>
5c93316c	8	#include <asm/setup.h>
2572f00d JH	9
	10	#include "pic32mzda.h"
	11	#include "early_pin.h"
	12
	13	/* Default early console parameters */
	14	#define EARLY_CONSOLE_PORT 1
	15	#define EARLY_CONSOLE_BAUDRATE 115200
	16
	17	#define UART_ENABLE BIT(15)
	18	#define UART_ENABLE_RX BIT(12)
	19	#define UART_ENABLE_TX BIT(10)
	20	#define UART_TX_FULL BIT(9)
	21
	22	/* UART1(x == 0) - UART6(x == 5) */
	23	#define UART_BASE(x) ((x) * 0x0200)
	24	#define U_MODE(x) UART_BASE(x)
	25	#define U_STA(x) (UART_BASE(x) + 0x10)
	26	#define U_TXR(x) (UART_BASE(x) + 0x20)
	27	#define U_BRG(x) (UART_BASE(x) + 0x40)
	28
	29	static void __iomem *uart_base;
	30	static char console_port = -1;
	31
	32	static int __init configure_uart_pins(int port)
	33	{
	34	switch (port) {
	35	case 1:
	36	pic32_pps_input(IN_FUNC_U2RX, IN_RPB0);
	37	pic32_pps_output(OUT_FUNC_U2TX, OUT_RPG9);
	38	break;
	39	case 5:
	40	pic32_pps_input(IN_FUNC_U6RX, IN_RPD0);
	41	pic32_pps_output(OUT_FUNC_U6TX, OUT_RPB8);
	42	break;
	43	default:
	44	return -1;
	45	}
	46
	47	return 0;
	48	}
	49
	50	static void __init configure_uart(char port, int baud)
	51	{
	52	u32 pbclk;
	53
	54	pbclk = pic32_get_pbclk(2);
	55
	56	__raw_writel(0, uart_base + U_MODE(port));
	57	__raw_writel(((pbclk / baud) / 16) - 1, uart_base + U_BRG(port));
	58	__raw_writel(UART_ENABLE, uart_base + U_MODE(port));
	59	__raw_writel(UART_ENABLE_TX \| UART_ENABLE_RX,
	60	uart_base + PIC32_SET(U_STA(port)));
	61	}
	62
	63	static void __init setup_early_console(char port, int baud)
	64	{
	65	if (configure_uart_pins(port))
	66	return;
	67
	68	console_port = port;
	69	configure_uart(console_port, baud);
	70	}
	71
	72	static char * __init pic32_getcmdline(void)
73	{
74	/*
75	* arch_mem_init() has not been called yet, so we don't have a real
76	* command line setup if using CONFIG_CMDLINE_BOOL.
77	*/
78	#ifdef CONFIG_CMDLINE_OVERRIDE
79	return CONFIG_CMDLINE;
80	#else
81	return fw_getcmdline();
82	#endif
83	}
84
85	static int __init get_port_from_cmdline(char *arch_cmdline)
86	{
87	char *s;
88	int port = -1;
89
90	if (!arch_cmdline \|\| *arch_cmdline == '\0')
91	goto _out;
92
93	s = strstr(arch_cmdline, "earlyprintk=");
94	if (s) {
95	s = strstr(s, "ttyS");
96	if (s)
97	s += 4;
98	else
99	goto _out;
100
101	port = (*s) - '0';
102	}
103
104	_out:
105	return port;
106	}
107
108	static int __init get_baud_from_cmdline(char *arch_cmdline)
109	{
110	char *s;
111	int baud = -1;
112
113	if (!arch_cmdline \|\| *arch_cmdline == '\0')
114	goto _out;
115
116	s = strstr(arch_cmdline, "earlyprintk=");
117	if (s) {
118	s = strstr(s, "ttyS");
119	if (s)
120	s += 6;
121	else
122	goto _out;
123
124	baud = 0;
125	while (s >= '0' && s <= '9')
126	baud = baud * 10 + *s++ - '0';
127	}
128
129	_out:
130	return baud;
131	}
132
133	void __init fw_init_early_console(char port)
134	{
135	char *arch_cmdline = pic32_getcmdline();
136	int baud = -1;
137
138	uart_base = ioremap_nocache(PIC32_BASE_UART, 0xc00);
139
140	baud = get_baud_from_cmdline(arch_cmdline);
141	if (port == -1)
142	port = get_port_from_cmdline(arch_cmdline);
143
144	if (port == -1)
145	port = EARLY_CONSOLE_PORT;
146
147	if (baud == -1)
148	baud = EARLY_CONSOLE_BAUDRATE;
149
150	setup_early_console(port, baud);
151	}
152
5c93316c	153	void prom_putchar(char c)
2572f00d JH	154	{
	155	if (console_port >= 0) {
	156	while (__raw_readl(
	157	uart_base + U_STA(console_port)) & UART_TX_FULL)
	158	;
	159
	160	__raw_writel(c, uart_base + U_TXR(console_port));
	161	}
2572f00d	162	}