MIPS: ath25: add UART support

Signed-off-by: Sergey Ryazanov <ryazanov.s.a@gmail.com>
Cc: Linux MIPS <linux-mips@linux-mips.org>
Patchwork: https://patchwork.linux-mips.org/patch/8242/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

arch/mips/ath25/ar2315.c

@@ -267,3 +267,11 @@ void __init ar2315_plat_mem_setup(void)
 
 	_machine_restart = ar2315_restart;
 }
+
+void __init ar2315_arch_init(void)
+{
+	unsigned irq = irq_create_mapping(ar2315_misc_irq_domain,
+					  AR2315_MISC_IRQ_UART0);
+
+	ath25_serial_setup(AR2315_UART0_BASE, irq, ar2315_apb_frequency());
+}

arch/mips/ath25/ar2315.h

@@ -6,12 +6,14 @@
 void ar2315_arch_init_irq(void);
 void ar2315_plat_time_init(void);
 void ar2315_plat_mem_setup(void);
+void ar2315_arch_init(void);
 
 #else
 
 static inline void ar2315_arch_init_irq(void) {}
 static inline void ar2315_plat_time_init(void) {}
 static inline void ar2315_plat_mem_setup(void) {}
+static inline void ar2315_arch_init(void) {}
 
 #endif
 

arch/mips/ath25/ar5312.c

@@ -265,3 +265,11 @@ void __init ar5312_plat_mem_setup(void)
 
 	_machine_restart = ar5312_restart;
 }
+
+void __init ar5312_arch_init(void)
+{
+	unsigned irq = irq_create_mapping(ar5312_misc_irq_domain,
+					  AR5312_MISC_IRQ_UART0);
+
+	ath25_serial_setup(AR5312_UART0_BASE, irq, ar5312_sys_frequency());
+}

arch/mips/ath25/ar5312.h

@@ -6,12 +6,14 @@
 void ar5312_arch_init_irq(void);
 void ar5312_plat_time_init(void);
 void ar5312_plat_mem_setup(void);
+void ar5312_arch_init(void);
 
 #else
 
 static inline void ar5312_arch_init_irq(void) {}
 static inline void ar5312_plat_time_init(void) {}
 static inline void ar5312_plat_mem_setup(void) {}
+static inline void ar5312_arch_init(void) {}
 
 #endif
 

arch/mips/ath25/devices.c

@@ -1,10 +1,41 @@
 #include <linux/kernel.h>
 #include <linux/init.h>
+#include <linux/serial_8250.h>
 #include <asm/bootinfo.h>
 
 #include "devices.h"
+#include "ar5312.h"
+#include "ar2315.h"
 
 const char *get_system_type(void)
 {
 	return "Atheros (unknown)";
 }
+
+void __init ath25_serial_setup(u32 mapbase, int irq, unsigned int uartclk)
+{
+	struct uart_port s;
+
+	memset(&s, 0, sizeof(s));
+
+	s.flags = UPF_BOOT_AUTOCONF | UPF_SKIP_TEST | UPF_IOREMAP;
+	s.iotype = UPIO_MEM32;
+	s.irq = irq;
+	s.regshift = 2;
+	s.mapbase = mapbase;
+	s.uartclk = uartclk;
+
+	early_serial_setup(&s);
+}
+
+static int __init ath25_arch_init(void)
+{
+	if (is_ar5312())
+		ar5312_arch_init();
+	else
+		ar2315_arch_init();
+
+	return 0;
+}
+
+arch_initcall(ath25_arch_init);

arch/mips/ath25/devices.h

@@ -9,6 +9,8 @@
 
 extern void (*ath25_irq_dispatch)(void);
 
+void ath25_serial_setup(u32 mapbase, int irq, unsigned int uartclk);
+
 static inline bool is_ar2315(void)
 {
 	return (current_cpu_data.cputype == CPU_4KEC);