[MIPS] TXx9: Support early_printk

Kill jmr3927-specific prom_putchar and add txx9-generic prom_putchar
to support early_printk.

Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

arch/mips/txx9/Kconfig

@@ -30,6 +30,7 @@ config SOC_TX3927
 	select IRQ_TXX9
 	select SWAP_IO_SPACE
 	select SYS_HAS_CPU_TX39XX
+	select SYS_HAS_EARLY_PRINTK
 	select SYS_SUPPORTS_32BIT_KERNEL
 	select SYS_SUPPORTS_LITTLE_ENDIAN
 	select SYS_SUPPORTS_BIG_ENDIAN
@@ -49,6 +50,7 @@ config SOC_TX4927
 	select PCI_TX4927
 	select SWAP_IO_SPACE
 	select SYS_HAS_CPU_TX49XX
+	select SYS_HAS_EARLY_PRINTK
 	select SYS_SUPPORTS_32BIT_KERNEL
 	select SYS_SUPPORTS_64BIT_KERNEL
 	select SYS_SUPPORTS_LITTLE_ENDIAN
@@ -70,6 +72,7 @@ config SOC_TX4938
 	select PCI_TX4927
 	select SWAP_IO_SPACE
 	select SYS_HAS_CPU_TX49XX
+	select SYS_HAS_EARLY_PRINTK
 	select SYS_SUPPORTS_32BIT_KERNEL
 	select SYS_SUPPORTS_64BIT_KERNEL
 	select SYS_SUPPORTS_LITTLE_ENDIAN

arch/mips/txx9/generic/setup.c

@@ -271,6 +271,37 @@ void __init txx9_sio_init(unsigned long baseaddr, int irq,
 #endif /* CONFIG_SERIAL_TXX9 */
 }
 
+#ifdef CONFIG_EARLY_PRINTK
+static void __init null_prom_putchar(char c)
+{
+}
+void (*txx9_prom_putchar)(char c) __initdata = null_prom_putchar;
+
+void __init prom_putchar(char c)
+{
+	txx9_prom_putchar(c);
+}
+
+static void __iomem *early_txx9_sio_port;
+
+static void __init early_txx9_sio_putchar(char c)
+{
+#define TXX9_SICISR	0x0c
+#define TXX9_SITFIFO	0x1c
+#define TXX9_SICISR_TXALS	0x00000002
+	while (!(__raw_readl(early_txx9_sio_port + TXX9_SICISR) &
+		 TXX9_SICISR_TXALS))
+		;
+	__raw_writel(c, early_txx9_sio_port + TXX9_SITFIFO);
+}
+
+void __init txx9_sio_putchar_init(unsigned long baseaddr)
+{
+	early_txx9_sio_port = ioremap(baseaddr, 0x24);
+	txx9_prom_putchar = early_txx9_sio_putchar;
+}
+#endif /* CONFIG_EARLY_PRINTK */
+
 /* wrappers */
 void __init plat_mem_setup(void)
 {

arch/mips/txx9/jmr3927/prom.c

@@ -41,22 +41,6 @@
 #include <asm/txx9/generic.h>
 #include <asm/txx9/jmr3927.h>
 
-#define TIMEOUT       0xffffff
-
-void
-prom_putchar(char c)
-{
-        int i = 0;
-
-        do {
-            i++;
-            if (i>TIMEOUT)
-                break;
-        } while (!(tx3927_sioptr(1)->cisr & TXx927_SICISR_TXALS));
-	tx3927_sioptr(1)->tfifo = c;
-	return;
-}
-
 void __init jmr3927_prom_init(void)
 {
 	/* CCFG */
@@ -65,4 +49,5 @@ void __init jmr3927_prom_init(void)
 
 	prom_init_cmdline();
 	add_memory_region(0, JMR3927_SDRAM_SIZE, BOOT_MEM_RAM);
+	txx9_sio_putchar_init(TX3927_SIO_REG(1));
 }

arch/mips/txx9/rbtx4927/prom.c

@@ -38,4 +38,5 @@ void __init rbtx4927_prom_init(void)
 {
 	prom_init_cmdline();
 	add_memory_region(0, tx4927_get_mem_size(), BOOT_MEM_RAM);
+	txx9_sio_putchar_init(TX4927_SIO_REG(0) & 0xfffffffffULL);
 }

arch/mips/txx9/rbtx4938/prom.c

@@ -22,4 +22,5 @@ void __init rbtx4938_prom_init(void)
 	prom_init_cmdline();
 #endif
 	add_memory_region(0, tx4938_get_mem_size(), BOOT_MEM_RAM);
+	txx9_sio_putchar_init(TX4938_SIO_REG(0) & 0xfffffffffULL);
 }

include/asm-mips/txx9/generic.h

@@ -49,5 +49,14 @@ void txx9_spi_init(int busid, unsigned long base, int irq);
 void txx9_ethaddr_init(unsigned int id, unsigned char *ethaddr);
 void txx9_sio_init(unsigned long baseaddr, int irq,
 		   unsigned int line, unsigned int sclk, int nocts);
+void prom_putchar(char c);
+#ifdef CONFIG_EARLY_PRINTK
+extern void (*txx9_prom_putchar)(char c);
+void txx9_sio_putchar_init(unsigned long baseaddr);
+#else
+static inline void txx9_sio_putchar_init(unsigned long baseaddr)
+{
+}
+#endif
 
 #endif /* __ASM_TXX9_GENERIC_H */