rockchip: Implement spl_gpio in the GPIO driver

Allow rockchip boards to use GPIOs before driver model is ready. This is
really only useful for setting GPIOs to enable the early debug console, if
needed on some platforms.

Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Philipp Tomsich <philipp.tomsich@theobroma-systems.com>

2 files changed, 69 insertions, 0 deletions

diff --git a/arch/arm/include/asm/arch-rockchip/gpio.h b/arch/arm/include/asm/arch-rockchip/gpio.h
index 0e3b57d0ef1..1aaec5faecc 100644
--- a/arch/arm/include/asm/arch-rockchip/gpio.h
+++ b/arch/arm/include/asm/arch-rockchip/gpio.h
@@ -31,4 +31,27 @@ enum gpio_pu_pd {
 	GPIO_PULL_REPEAT,
 };
 
+/* These defines are only used by spl_gpio.h */
+enum {
+	/* Banks have 8 GPIOs, so 3 bits, and there are 4 banks, so 2 bits */
+	GPIO_BANK_SHIFT		= 3,
+	GPIO_BANK_MASK		= 3 << GPIO_BANK_SHIFT,
+
+	GPIO_OFFSET_MASK	= 0x1f,
+};
+
+#define GPIO(bank, offset)	((bank) << GPIO_BANK_SHIFT | (offset))
+
+enum gpio_bank_t {
+	BANK_A = 0,
+	BANK_B,
+	BANK_C,
+	BANK_D,
+};
+
+enum gpio_dir_t {
+	GPIO_INPUT = 0,
+	GPIO_OUTPUT,
+};
+
 #endif
diff --git a/drivers/gpio/rk_gpio.c b/drivers/gpio/rk_gpio.c
index a8f311bbd67..21df2277176 100644
--- a/drivers/gpio/rk_gpio.c
+++ b/drivers/gpio/rk_gpio.c
@@ -91,6 +91,52 @@ static int rockchip_gpio_get_function(struct udevice *dev, unsigned offset)
 #endif
 }
 
+/* Simple SPL interface to GPIOs */
+#ifdef CONFIG_SPL_BUILD
+
+enum {
+	PULL_NONE_1V8 = 0,
+	PULL_DOWN_1V8 = 1,
+	PULL_UP_1V8 = 3,
+};
+
+int spl_gpio_set_pull(void *vregs, uint gpio, int pull)
+{
+	u32 *regs = vregs;
+	uint val;
+
+	regs += gpio >> GPIO_BANK_SHIFT;
+	gpio &= GPIO_OFFSET_MASK;
+	switch (pull) {
+	case GPIO_PULL_UP:
+		val = PULL_UP_1V8;
+		break;
+	case GPIO_PULL_DOWN:
+		val = PULL_DOWN_1V8;
+		break;
+	case GPIO_PULL_NORMAL:
+	default:
+		val = PULL_NONE_1V8;
+		break;
+	}
+	clrsetbits_le32(regs, 3 << (gpio * 2), val << (gpio * 2));
+
+	return 0;
+}
+
+int spl_gpio_output(void *vregs, uint gpio, int value)
+{
+	struct rockchip_gpio_regs * const regs = vregs;
+
+	clrsetbits_le32(&regs->swport_dr, 1 << gpio, value << gpio);
+
+	/* Set direction */
+	clrsetbits_le32(&regs->swport_ddr, 1 << gpio, 1 << gpio);
+
+	return 0;
+}
+#endif /* CONFIG_SPL_BUILD */
+
 static int rockchip_gpio_probe(struct udevice *dev)
 {
 	struct gpio_dev_priv *uc_priv = dev_get_uclass_priv(dev);