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authorAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
committerAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
commit57f0f512b273f60d52568b8c6b77e17f5636edc0 (patch)
tree5e910f0e82173f4ef4f51111366a3f1299037a7b /arch/sparc/prom/printf.c
Initial import
Diffstat (limited to 'arch/sparc/prom/printf.c')
-rw-r--r--arch/sparc/prom/printf.c69
1 files changed, 69 insertions, 0 deletions
diff --git a/arch/sparc/prom/printf.c b/arch/sparc/prom/printf.c
new file mode 100644
index 000000000..d9682f06b
--- /dev/null
+++ b/arch/sparc/prom/printf.c
@@ -0,0 +1,69 @@
+/*
+ * printf.c: Internal prom library printf facility.
+ *
+ * Copyright (C) 1995 David S. Miller (davem@caip.rutgers.edu)
+ * Copyright (C) 1997 Jakub Jelinek (jj@sunsite.mff.cuni.cz)
+ * Copyright (c) 2002 Pete Zaitcev (zaitcev@yahoo.com)
+ *
+ * We used to warn all over the code: DO NOT USE prom_printf(),
+ * and yet people do. Anton's banking code was outputting banks
+ * with prom_printf for most of the 2.4 lifetime. Since an effective
+ * stick is not available, we deployed a carrot: an early printk
+ * through PROM by means of -p boot option. This ought to fix it.
+ * USE printk; if you need, deploy -p.
+ */
+
+#include <linux/kernel.h>
+#include <linux/compiler.h>
+#include <linux/spinlock.h>
+
+#include <asm/openprom.h>
+#include <asm/oplib.h>
+
+#define CONSOLE_WRITE_BUF_SIZE 1024
+
+static char ppbuf[1024];
+static char console_write_buf[CONSOLE_WRITE_BUF_SIZE];
+static DEFINE_RAW_SPINLOCK(console_write_lock);
+
+void notrace prom_write(const char *buf, unsigned int n)
+{
+ unsigned int dest_len;
+ unsigned long flags;
+ char *dest;
+
+ dest = console_write_buf;
+ raw_spin_lock_irqsave(&console_write_lock, flags);
+
+ dest_len = 0;
+ while (n-- != 0) {
+ char ch = *buf++;
+ if (ch == '\n') {
+ *dest++ = '\r';
+ dest_len++;
+ }
+ *dest++ = ch;
+ dest_len++;
+ if (dest_len >= CONSOLE_WRITE_BUF_SIZE - 1) {
+ prom_console_write_buf(console_write_buf, dest_len);
+ dest = console_write_buf;
+ dest_len = 0;
+ }
+ }
+ if (dest_len)
+ prom_console_write_buf(console_write_buf, dest_len);
+
+ raw_spin_unlock_irqrestore(&console_write_lock, flags);
+}
+
+void notrace prom_printf(const char *fmt, ...)
+{
+ va_list args;
+ int i;
+
+ va_start(args, fmt);
+ i = vscnprintf(ppbuf, sizeof(ppbuf), fmt, args);
+ va_end(args);
+
+ prom_write(ppbuf, i);
+}