diff options
Diffstat (limited to 'kernel/arch/mips/ralink/early_printk.c')
| -rw-r--r-- | kernel/arch/mips/ralink/early_printk.c | 26 |
1 files changed, 26 insertions, 0 deletions
diff --git a/kernel/arch/mips/ralink/early_printk.c b/kernel/arch/mips/ralink/early_printk.c index 255d695ec..3c59ffe5f 100644 --- 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) |