inmates: arm: make uart drivers runtime selectable

Without additional cmdline arguments, inmates will use an empty debug
output driver. Following cmdline arguments can be used to select a
specific driver:

con-type
  "8250" or "PL011"

con-base
  UART-MMIO base address

con-divider
  Optional: UART divider. Zero value means to skip initialisation.
            Defaults to 0.

con-clock_reg
con-gate_nr
  Optional: Clock Register and Gate Nr

Signed-off-by: Ralf Ramsauer <ralf.ramsauer@oth-regensburg.de>
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>

inmates/lib/arm/Makefile

@@ -16,9 +16,8 @@ always := lib.a
 
 ccflags-y := -ffunction-sections
 
-lib-y				:= header.o gic.o printk.o timer.o
+lib-y				:= header.o gic.o printk.o timer.o \
+				   uart-pl011.o uart-8250.o
 lib-y				+= ../string.o ../cmdline.o
 lib-$(CONFIG_ARM_GIC_V2)	+= gic-v2.o
 lib-$(CONFIG_ARM_GIC_V3)	+= gic-v3.o
-lib-$(CONFIG_SERIAL_AMBA_PL011)	+= uart-pl011.o
-lib-$(CONFIG_SERIAL_8250)	+= uart-8250.o

inmates/lib/arm/printk.c

@@ -15,7 +15,9 @@
 #include <uart.h>
 #include <mach/uart.h>
 
-extern struct uart_chip uart_ops;
+static struct uart_chip *chip = NULL;
+
+extern struct uart_chip uart_8250_ops, uart_pl011_ops;
 
 static void console_write(const char *msg)
 {
@@ -29,11 +31,34 @@ static void console_write(const char *msg)
 		if (!c)
 			break;
 
-		uart_ops.wait(&uart_ops);
-		uart_ops.write(&uart_ops, c);
+		chip->wait(chip);
+		chip->write(chip, c);
 	}
 }
 
+static void console_init(void)
+{
+	char buf[32];
+	const char *type;
+
+	type = cmdline_parse_str("con-type", buf, sizeof(buf), "none");
+	if (!strncmp(type, "8250", 4))
+		chip = &uart_8250_ops;
+	else if (!strncmp(type, "PL011", 5))
+		chip = &uart_pl011_ops;
+
+	if (!chip)
+		return;
+
+	chip->base = (void *)(unsigned long) cmdline_parse_int("con-base", 0);
+	chip->divider = cmdline_parse_int("con-divider", 0);
+	chip->gate_nr = cmdline_parse_int("con-gate_nr", 0);
+	chip->clock_reg = (void *)(unsigned long)
+		cmdline_parse_int("con-clock_reg", 0);
+
+	chip->init(chip);
+}
+
 #include "../../../hypervisor/printk-core.c"
 
 void printk(const char *fmt, ...)
@@ -42,11 +67,13 @@ void printk(const char *fmt, ...)
 	va_list ap;
 
 	if (!inited) {
-		uart_ops.base = UART_BASE;
-		uart_ops.init(&uart_ops);
+		console_init();
 		inited = true;
 	}
 
+	if (!chip)
+		return;
+
 	va_start(ap, fmt);
 
 	__vprintk(fmt, ap);

inmates/lib/arm/uart-8250.c

@@ -51,7 +51,7 @@ static void uart_write(struct uart_chip *chip, char c)
 	mmio_write32(chip->base + UART_TX, c);
 }
 
-struct uart_chip uart_ops = {
+struct uart_chip uart_8250_ops = {
 	.init = uart_init,
 	.wait = uart_wait,
 	.write = uart_write,

inmates/lib/arm/uart-pl011.c

@@ -66,7 +66,7 @@ static void uart_write(struct uart_chip *chip, char c)
 	mmio_write32(chip->base + UARTDR, c);
 }
 
-struct uart_chip uart_ops = {
+struct uart_chip uart_pl011_ops = {
 	.init = uart_init,
 	.wait = uart_wait,
 	.write = uart_write,

inmates/lib/arm64/Makefile

@@ -17,6 +17,5 @@ always := lib.a
 lib-y				:= header.o
 lib-y				+= ../arm/gic.o ../arm/printk.o ../arm/timer.o
 lib-y				+= ../string.o ../cmdline.o
+lib-y				+= ../arm/uart-pl011.o ../arm/uart-8250.o
 lib-$(CONFIG_ARM_GIC_V2)	+= ../arm/gic-v2.o
-lib-$(CONFIG_SERIAL_AMBA_PL011)	+= ../arm/uart-pl011.o
-lib-$(CONFIG_SERIAL_8250)	+= ../arm/uart-8250.o