These changes are the raw update to linux-4.4.6-rt14. Kernel sources

[kvmfornfv.git] / kernel / arch / mips / ralink / early_printk.c

diff --git a/kernel/arch/mips/ralink/early_printk.c b/kernel/arch/mips/ralink/early_printk.c
index 255d695..3c59ffe 100644 (file)
--- a/kernel/arch/mips/ralink/early_printk.c
+++ b/kernel/arch/mips/ralink/early_printk.c
@@ -25,11 +25,13 @@
 #define MT7628_CHIP_NAME1      0x20203832
 
 #define UART_REG_TX            0x04
+#define UART_REG_LCR           0x0c
 #define UART_REG_LSR           0x14
 #define UART_REG_LSR_RT2880    0x1c
 
 static __iomem void *uart_membase = (__iomem void *) KSEG1ADDR(EARLY_UART_BASE);
 static __iomem void *chipid_membase = (__iomem void *) KSEG1ADDR(CHIPID_BASE);
+static int init_complete;
 
 static inline void uart_w32(u32 val, unsigned reg)
 {
@@ -47,8 +49,32 @@ static inline int soc_is_mt7628(void)
                (__raw_readl(chipid_membase) == MT7628_CHIP_NAME1);
 }
 
+static void find_uart_base(void)
+{
+       int i;
+
+       if (!soc_is_mt7628())
+               return;
+
+       for (i = 0; i < 3; i++) {
+               u32 reg = uart_r32(UART_REG_LCR + (0x100 * i));
+
+               if (!reg)
+                       continue;
+
+               uart_membase = (__iomem void *) KSEG1ADDR(EARLY_UART_BASE +
+                                                         (0x100 * i));
+               break;
+       }
+}
+
 void prom_putchar(unsigned char ch)
 {
+       if (!init_complete) {
+               find_uart_base();
+               init_complete = 1;
+       }
+
        if (IS_ENABLED(CONFIG_SOC_MT7621) || soc_is_mt7628()) {
                uart_w32(ch, UART_TX);
                while ((uart_r32(UART_REG_LSR) & UART_LSR_THRE) == 0)