From 2aa8e37596933a43fc3e46e1e385045635674429 Mon Sep 17 00:00:00 2001
From: Michal Simek <monstr@monstr.eu>
Date: Thu, 14 Apr 2011 11:48:43 +0200
Subject: microblaze: Simplify early console binding from DT

Recognize early Linux console from chosen - linux,stdout-path
instead of detecting the first console with appropriate
compatible strings.
This patch solved the problem on system with multiple
consoles.

Signed-off-by: Michal Simek <monstr@monstr.eu>
---
 arch/microblaze/kernel/prom.c | 96 +++++++++++++++++++------------------------
 1 file changed, 42 insertions(+), 54 deletions(-)

(limited to 'arch/microblaze/kernel/prom.c')

diff --git a/arch/microblaze/kernel/prom.c b/arch/microblaze/kernel/prom.c
index b15cc219b1d9..18d9371d9b26 100644
--- a/arch/microblaze/kernel/prom.c
+++ b/arch/microblaze/kernel/prom.c
@@ -53,69 +53,57 @@ void * __init early_init_dt_alloc_memory_arch(u64 size, u64 align)
 }
 
 #ifdef CONFIG_EARLY_PRINTK
-/* MS this is Microblaze specifig function */
-static int __init early_init_dt_scan_serial(unsigned long node,
-				const char *uname, int depth, void *data)
-{
-	unsigned long l;
-	char *p;
-	const __be32 *addr;
-
-	pr_debug("search \"serial\", depth: %d, uname: %s\n", depth, uname);
-
-/* find all serial nodes */
-	if (strncmp(uname, "serial", 6) != 0)
-		return 0;
-
-/* find compatible node with uartlite */
-	p = of_get_flat_dt_prop(node, "compatible", &l);
-	if ((strncmp(p, "xlnx,xps-uartlite", 17) != 0) &&
-			(strncmp(p, "xlnx,opb-uartlite", 17) != 0) &&
-			(strncmp(p, "xlnx,axi-uartlite", 17) != 0))
-		return 0;
-
-	addr = of_get_flat_dt_prop(node, "reg", &l);
-	return be32_to_cpup(addr); /* return address */
-}
+char *stdout;
 
-/* this function is looking for early uartlite console - Microblaze specific */
-int __init early_uartlite_console(void)
-{
-	return of_scan_flat_dt(early_init_dt_scan_serial, NULL);
-}
-
-/* MS this is Microblaze specifig function */
-static int __init early_init_dt_scan_serial_full(unsigned long node,
+int __init early_init_dt_scan_chosen_serial(unsigned long node,
 				const char *uname, int depth, void *data)
 {
 	unsigned long l;
 	char *p;
-	unsigned int addr;
-
-	pr_debug("search \"chosen\", depth: %d, uname: %s\n", depth, uname);
-
-/* find all serial nodes */
-	if (strncmp(uname, "serial", 6) != 0)
-		return 0;
 
-	early_init_dt_check_for_initrd(node);
-
-/* find compatible node with uartlite */
-	p = of_get_flat_dt_prop(node, "compatible", &l);
-
-	if ((strncmp(p, "xlnx,xps-uart16550", 18) != 0) &&
-		(strncmp(p, "xlnx,axi-uart16550", 18) != 0))
-		return 0;
-
-	addr = *(u32 *)of_get_flat_dt_prop(node, "reg", &l);
-	addr += *(u32 *)of_get_flat_dt_prop(node, "reg-offset", &l);
-	return be32_to_cpu(addr); /* return address */
+	pr_debug("%s: depth: %d, uname: %s\n", __func__, depth, uname);
+
+	if (depth == 1 && (strcmp(uname, "chosen") == 0 ||
+				strcmp(uname, "chosen@0") == 0)) {
+		p = of_get_flat_dt_prop(node, "linux,stdout-path", &l);
+		if (p != NULL && l > 0)
+			stdout = p; /* store pointer to stdout-path */
+	}
+
+	if (stdout && strstr(stdout, uname)) {
+		p = of_get_flat_dt_prop(node, "compatible", &l);
+		pr_debug("Compatible string: %s\n", p);
+
+		if ((strncmp(p, "xlnx,xps-uart16550", 18) == 0) ||
+			(strncmp(p, "xlnx,axi-uart16550", 18) == 0)) {
+			unsigned int addr;
+
+			*(u32 *)data = UART16550;
+
+			addr = *(u32 *)of_get_flat_dt_prop(node, "reg", &l);
+			addr += *(u32 *)of_get_flat_dt_prop(node,
+							"reg-offset", &l);
+			/* clear register offset */
+			return be32_to_cpu(addr) & ~3;
+		}
+		if ((strncmp(p, "xlnx,xps-uartlite", 17) == 0) ||
+				(strncmp(p, "xlnx,opb-uartlite", 17) == 0) ||
+				(strncmp(p, "xlnx,axi-uartlite", 17) == 0)) {
+			unsigned int *addrp;
+
+			*(u32 *)data = UARTLITE;
+
+			addrp = of_get_flat_dt_prop(node, "reg", &l);
+			return be32_to_cpup(addrp); /* return address */
+		}
+	}
+	return 0;
 }
 
-/* this function is looking for early uartlite console - Microblaze specific */
-int __init early_uart16550_console(void)
+/* this function is looking for early console - Microblaze specific */
+int __init of_early_console(void *version)
 {
-	return of_scan_flat_dt(early_init_dt_scan_serial_full, NULL);
+	return of_scan_flat_dt(early_init_dt_scan_chosen_serial, version);
 }
 #endif
 
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