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Diffstat (limited to 'arch/arm64/kernel/early_printk.c')
-rw-r--r--arch/arm64/kernel/early_printk.c158
1 files changed, 0 insertions, 158 deletions
diff --git a/arch/arm64/kernel/early_printk.c b/arch/arm64/kernel/early_printk.c
deleted file mode 100644
index ffbbdde7aba1..000000000000
--- a/arch/arm64/kernel/early_printk.c
+++ /dev/null
@@ -1,158 +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) {
- set_fixmap_io(FIX_EARLYCON_MEM_BASE, paddr);
- early_base = (void __iomem *)fix_to_virt(FIX_EARLYCON_MEM_BASE);
- }
-
- printch = match->printch;
- early_console = &early_console_dev;
- register_console(&early_console_dev);
-
- return 0;
-}
-
-early_param("earlyprintk", setup_early_printk);