3 files changed, 48 insertions, 25 deletions

diff --git a/arch/sparc/prom/console_32.c b/arch/sparc/prom/console_32.c
index 157019e29fd4..48863108a44c 100644
--- a/arch/sparc/prom/console_32.c
+++ b/arch/sparc/prom/console_32.c
@@ -43,12 +43,14 @@ static int prom_nbputchar(const char *buf)
 	return i; /* Ugh, we could spin forever on unsupported proms ;( */
 }
 
-/* Blocking version of put character routine above. */
-void prom_putchar(const char *buf)
+void prom_console_write_buf(const char *buf, int len)
 {
-	while (1) {
-		int err = prom_nbputchar(buf);
-		if (!err)
-			break;
+	while (len) {
+		int n = prom_nbputchar(buf);
+		if (n)
+			continue;
+		len--;
+		buf++;
 	}
 }
+
diff --git a/arch/sparc/prom/console_64.c b/arch/sparc/prom/console_64.c
index 0da88d10beff..ed39e75828bd 100644
--- a/arch/sparc/prom/console_64.c
+++ b/arch/sparc/prom/console_64.c
@@ -15,35 +15,34 @@
 
 extern int prom_stdin, prom_stdout;
 
-/* Non blocking put character to console device, returns -1 if
- * unsuccessful.
- */
-static int prom_nbputchar(const char *buf)
+static int __prom_console_write_buf(const char *buf, int len)
 {
 	unsigned long args[7];
+	int ret;
 
 	args[0] = (unsigned long) "write";
 	args[1] = 3;
 	args[2] = 1;
 	args[3] = (unsigned int) prom_stdout;
 	args[4] = (unsigned long) buf;
-	args[5] = 1;
+	args[5] = (unsigned int) len;
 	args[6] = (unsigned long) -1;
 
 	p1275_cmd_direct(args);
 
-	if (args[6] == 1)
-		return 0;
-	else
+	ret = (int) args[6];
+	if (ret < 0)
 		return -1;
+	return ret;
 }
 
-/* Blocking version of put character routine above. */
-void prom_putchar(const char *buf)
+void prom_console_write_buf(const char *buf, int len)
 {
-	while (1) {
-		int err = prom_nbputchar(buf);
-		if (!err)
-			break;
+	while (len) {
+		int n = __prom_console_write_buf(buf, len);
+		if (n < 0)
+			continue;
+		len -= n;
+		buf += len;
 	}
 }
diff --git a/arch/sparc/prom/printf.c b/arch/sparc/prom/printf.c
index 24031971f806..d9682f06b3b0 100644
--- a/arch/sparc/prom/printf.c
+++ b/arch/sparc/prom/printf.c
@@ -15,23 +15,45 @@
 
 #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;
+		char ch = *buf++;
 		if (ch == '\n') {
-			char tmp = '\r';
-			prom_putchar(&tmp);
+			*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;
 		}
-		prom_putchar(buf);
-		buf++;
 	}
+	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, ...)