1 files changed, 29 insertions, 6 deletions

diff --git a/arch/sparc/prom/printf.c b/arch/sparc/prom/printf.c
index ca869266b9f3..d9682f06b3b0 100644
--- a/arch/sparc/prom/printf.c
+++ b/arch/sparc/prom/printf.c
@@ -15,22 +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)
 {
-        char ch;
+        unsigned int dest_len;
+        unsigned long flags;
+        char *dest;
+
+        dest = console_write_buf;
+        raw_spin_lock_irqsave(&console_write_lock, flags);
 
-        while (n != 0) {
-                --n;
-                if ((ch = *buf++) == '\n')
-                        prom_putchar('\r');
-                prom_putchar(ch);
+        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, ...)