diff options
Diffstat (limited to 'arch/arm64/kernel/early_printk.c')
-rw-r--r-- | arch/arm64/kernel/early_printk.c | 156 |
1 files changed, 0 insertions, 156 deletions
diff --git a/arch/arm64/kernel/early_printk.c b/arch/arm64/kernel/early_printk.c deleted file mode 100644 index 2dc36d00addf..000000000000 --- a/arch/arm64/kernel/early_printk.c +++ /dev/null @@ -1,156 +0,0 @@ -/* - * Earlyprintk support. - * - * Copyright (C) 2012 ARM Ltd. - * Author: Catalin Marinas <catalin.marinas@arm.com> - * - * This program is free software: you can redistribute 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 that 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. - * - * You should have received a copy of the GNU General Public License - * along with this program. If not, see <http://www.gnu.org/licenses/>. - */ -#include <linux/kernel.h> -#include <linux/console.h> -#include <linux/init.h> -#include <linux/string.h> -#include <linux/mm.h> -#include <linux/io.h> - -#include <linux/amba/serial.h> -#include <linux/serial_reg.h> - -#include <asm/fixmap.h> - -static void __iomem *early_base; -static void (*printch)(char ch); - -/* - * PL011 single character TX. - */ -static void pl011_printch(char ch) -{ - while (readl_relaxed(early_base + UART01x_FR) & UART01x_FR_TXFF) - ; - writeb_relaxed(ch, early_base + UART01x_DR); - while (readl_relaxed(early_base + UART01x_FR) & UART01x_FR_BUSY) - ; -} - -/* - * Semihosting-based debug console - */ -static void smh_printch(char ch) -{ - asm volatile("mov x1, %0\n" - "mov x0, #3\n" - "hlt 0xf000\n" - : : "r" (&ch) : "x0", "x1", "memory"); -} - -/* - * 8250/16550 (8-bit aligned registers) single character TX. - */ -static void uart8250_8bit_printch(char ch) -{ - while (!(readb_relaxed(early_base + UART_LSR) & UART_LSR_THRE)) - ; - writeb_relaxed(ch, early_base + UART_TX); -} - -/* - * 8250/16550 (32-bit aligned registers) single character TX. - */ -static void uart8250_32bit_printch(char ch) -{ - while (!(readl_relaxed(early_base + (UART_LSR << 2)) & UART_LSR_THRE)) - ; - writel_relaxed(ch, early_base + (UART_TX << 2)); -} - -struct earlycon_match { - const char *name; - void (*printch)(char ch); -}; - -static const struct earlycon_match earlycon_match[] __initconst = { - { .name = "pl011", .printch = pl011_printch, }, - { .name = "smh", .printch = smh_printch, }, - { .name = "uart8250-8bit", .printch = uart8250_8bit_printch, }, - { .name = "uart8250-32bit", .printch = uart8250_32bit_printch, }, - {} -}; - -static void early_write(struct console *con, const char *s, unsigned n) -{ - while (n-- > 0) { - if (*s == '\n') - printch('\r'); - printch(*s); - s++; - } -} - -static struct console early_console_dev = { - .name = "earlycon", - .write = early_write, - .flags = CON_PRINTBUFFER | CON_BOOT, - .index = -1, -}; - -/* - * Parse earlyprintk=... parameter in the format: - * - * <name>[,<addr>][,<options>] - * - * and register the early console. It is assumed that the UART has been - * initialised by the bootloader already. - */ -static int __init setup_early_printk(char *buf) -{ - const struct earlycon_match *match = earlycon_match; - phys_addr_t paddr = 0; - - if (!buf) { - pr_warning("No earlyprintk arguments passed.\n"); - return 0; - } - - while (match->name) { - size_t len = strlen(match->name); - if (!strncmp(buf, match->name, len)) { - buf += len; - break; - } - match++; - } - if (!match->name) { - pr_warning("Unknown earlyprintk arguments: %s\n", buf); - return 0; - } - - /* I/O address */ - if (!strncmp(buf, ",0x", 3)) { - char *e; - paddr = simple_strtoul(buf + 1, &e, 16); - buf = e; - } - /* no options parsing yet */ - - if (paddr) - early_base = (void __iomem *)set_fixmap_offset_io(FIX_EARLYCON_MEM_BASE, paddr); - - printch = match->printch; - early_console = &early_console_dev; - register_console(&early_console_dev); - - return 0; -} - -early_param("earlyprintk", setup_early_printk); |