MIPS: ath25: add board configuration detection

All boards based on AR5312/AR2315 SoC have a special structure located
at the end of flash. This structure contains board-specific data such as
Ethernet and Wireless MAC addresses. The flash is mapped to the memmory
at predefined location.

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/8243/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

arch/mips/ath25/ar2315.c

@@ -160,6 +160,12 @@ void __init ar2315_arch_init_irq(void)
 	ar2315_misc_irq_domain = domain;
 }
 
+void __init ar2315_init_devices(void)
+{
+	/* Find board configuration */
+	ath25_find_config(AR2315_SPI_READ_BASE, AR2315_SPI_READ_SIZE);
+}
+
 static void ar2315_restart(char *command)
 {
 	void (*mips_reset_vec)(void) = (void *)0xbfc00000;