rockchip: rk3308: Add support for ROC-RK3308-CC board

ROC-RK3308-CC is a rk3308 based board designed by
Firelfy, with eMMC and 256MB DDR3 and RTL8188 Wifi
on board.

Signed-off-by: Andy Yan <andy.yan@rock-chips.com>
Reviewed-by: Kever Yang <kever.yang@rock-chips.com>
diff --git a/board/firefly/firefly-rk3308/roc_cc_rk3308.c b/board/firefly/firefly-rk3308/roc_cc_rk3308.c
new file mode 100644
index 0000000..5f0a659
--- /dev/null
+++ b/board/firefly/firefly-rk3308/roc_cc_rk3308.c
@@ -0,0 +1,81 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * (C) Copyright 2019 Rockchip Electronics Co., Ltd
+ */
+
+#include <common.h>
+#include <adc.h>
+#include <asm/io.h>
+#include <asm/arch/grf_rk3308.h>
+#include <asm/arch-rockchip/hardware.h>
+
+#if defined(CONFIG_DEBUG_UART)
+#define GRF_BASE	0xff000000
+
+enum {
+	GPIO1C7_SHIFT		= 8,
+	GPIO1C7_MASK		= GENMASK(11, 8),
+	GPIO1C7_GPIO		= 0,
+	GPIO1C7_UART1_RTSN,
+	GPIO1C7_UART2_TX_M0,
+	GPIO1C7_SPI2_MOSI,
+	GPIO1C7_JTAG_TMS,
+
+	GPIO1C6_SHIFT		= 4,
+	GPIO1C6_MASK		= GENMASK(7, 4),
+	GPIO1C6_GPIO		= 0,
+	GPIO1C6_UART1_CTSN,
+	GPIO1C6_UART2_RX_M0,
+	GPIO1C6_SPI2_MISO,
+	GPIO1C6_JTAG_TCLK,
+
+	GPIO4D3_SHIFT           = 6,
+	GPIO4D3_MASK            = GENMASK(7, 6),
+	GPIO4D3_GPIO            = 0,
+	GPIO4D3_SDMMC_D3,
+	GPIO4D3_UART2_TX_M1,
+
+	GPIO4D2_SHIFT           = 4,
+	GPIO4D2_MASK            = GENMASK(5, 4),
+	GPIO4D2_GPIO            = 0,
+	GPIO4D2_SDMMC_D2,
+	GPIO4D2_UART2_RX_M1,
+
+	UART2_IO_SEL_SHIFT	= 2,
+	UART2_IO_SEL_MASK	= GENMASK(3, 2),
+	UART2_IO_SEL_M0		= 0,
+	UART2_IO_SEL_M1,
+	UART2_IO_SEL_USB,
+};
+
+void board_debug_uart_init(void)
+{
+	static struct rk3308_grf * const grf = (void *)GRF_BASE;
+
+	/* Enable early UART2 channel m0 on the rk3308 */
+	rk_clrsetreg(&grf->soc_con5, UART2_IO_SEL_MASK,
+		     UART2_IO_SEL_M0 << UART2_IO_SEL_SHIFT);
+	rk_clrsetreg(&grf->gpio1ch_iomux,
+		     GPIO1C6_MASK | GPIO1C7_MASK,
+		     GPIO1C6_UART2_RX_M0 << GPIO1C6_SHIFT |
+		     GPIO1C7_UART2_TX_M0 << GPIO1C7_SHIFT);
+}
+#endif
+
+#define KEY_DOWN_MIN_VAL        0
+#define KEY_DOWN_MAX_VAL        30
+
+int rockchip_dnl_key_pressed(void)
+{
+	unsigned int val;
+
+	if (adc_channel_single_shot("saradc", 1, &val)) {
+		printf("%s read adc key val failed\n", __func__);
+		return false;
+	}
+
+	if (val >= KEY_DOWN_MIN_VAL && val <= KEY_DOWN_MAX_VAL)
+		return true;
+	else
+		return false;
+}