rockchip: rk3308: Add sdram driver

A dm based dram driver for rk3308 u-boot
to get capacity.

Signed-off-by: Andy Yan <andy.yan@rock-chips.com>
Reviewed-by: Kever Yang <kever.yang@rock-chips.com>
diff --git a/drivers/ram/rockchip/Makefile b/drivers/ram/rockchip/Makefile
index 217366b..c3ec89a 100644
--- a/drivers/ram/rockchip/Makefile
+++ b/drivers/ram/rockchip/Makefile
@@ -9,6 +9,7 @@
 obj-$(CONFIG_ROCKCHIP_RK3188) = sdram_rk3188.o
 obj-$(CONFIG_ROCKCHIP_RK322X) = sdram_rk322x.o
 obj-$(CONFIG_ROCKCHIP_RK3288) = sdram_rk3288.o
+obj-$(CONFIG_ROCKCHIP_RK3308) = sdram_rk3308.o
 obj-$(CONFIG_ROCKCHIP_RK3328) = sdram_rk3328.o sdram_pctl_px30.o sdram_phy_px30.o
 obj-$(CONFIG_ROCKCHIP_RK3399) += sdram_rk3399.o
 obj-$(CONFIG_ROCKCHIP_SDRAM_COMMON) += sdram_common.o
diff --git a/drivers/ram/rockchip/sdram_rk3308.c b/drivers/ram/rockchip/sdram_rk3308.c
new file mode 100644
index 0000000..310df79
--- /dev/null
+++ b/drivers/ram/rockchip/sdram_rk3308.c
@@ -0,0 +1,55 @@
+// SPDX-License-Identifier: GPL-2.0+ OR BSD-3-Clause
+/*
+ * (C) Copyright 2019 Rockchip Electronics Co., Ltd.
+ */
+
+#include <common.h>
+#include <dm.h>
+#include <ram.h>
+#include <syscon.h>
+#include <asm/arch/grf_rk3308.h>
+#include <asm/arch-rockchip/clock.h>
+#include <asm/arch-rockchip/sdram.h>
+
+struct dram_info {
+	struct ram_info info;
+	struct rk3308_grf *grf;
+};
+
+static int rk3308_dmc_probe(struct udevice *dev)
+{
+	struct dram_info *priv = dev_get_priv(dev);
+
+	priv->grf = syscon_get_first_range(ROCKCHIP_SYSCON_GRF);
+	priv->info.base = CONFIG_SYS_SDRAM_BASE;
+	priv->info.size = rockchip_sdram_size((phys_addr_t)&priv->grf->os_reg2);
+
+	return 0;
+}
+
+static int rk3308_dmc_get_info(struct udevice *dev, struct ram_info *info)
+{
+	struct dram_info *priv = dev_get_priv(dev);
+
+	*info = priv->info;
+
+	return 0;
+}
+
+static struct ram_ops rk3308_dmc_ops = {
+	.get_info = rk3308_dmc_get_info,
+};
+
+static const struct udevice_id rk3308_dmc_ids[] = {
+	{ .compatible = "rockchip,rk3308-dmc" },
+	{ }
+};
+
+U_BOOT_DRIVER(dmc_rk3308) = {
+	.name = "rockchip_rk3308_dmc",
+	.id = UCLASS_RAM,
+	.of_match = rk3308_dmc_ids,
+	.ops = &rk3308_dmc_ops,
+	.probe = rk3308_dmc_probe,
+	.priv_auto_alloc_size = sizeof(struct dram_info),
+};