3 files changed, 145 insertions, 0 deletions
diff --git a/drivers/soc/rockchip/Kconfig b/drivers/soc/rockchip/Kconfig
index 7140ff825598..20da55d9cbb1 100644
--- a/drivers/soc/rockchip/Kconfig
+++ b/drivers/soc/rockchip/Kconfig
@@ -3,6 +3,16 @@ if ARCH_ROCKCHIP || COMPILE_TEST
 #
 # Rockchip Soc drivers
 #
+
+config ROCKCHIP_GRF
+	bool
+	default y
+	help
+	  The General Register Files are a central component providing
+	  special additional settings registers for a lot of soc-components.
+	  In a lot of cases there also need to be default settings initialized
+	  to make some of them conform to expectations of the kernel.
+
 config ROCKCHIP_PM_DOMAINS
         bool "Rockchip generic power domain"
         depends on PM
diff --git a/drivers/soc/rockchip/Makefile b/drivers/soc/rockchip/Makefile
index 3d73d0672d22..c851fa0056d0 100644
--- a/drivers/soc/rockchip/Makefile
+++ b/drivers/soc/rockchip/Makefile
@@ -1,4 +1,5 @@
 #
 # Rockchip Soc drivers
 #
+obj-$(CONFIG_ROCKCHIP_GRF) += grf.o
 obj-$(CONFIG_ROCKCHIP_PM_DOMAINS) += pm_domains.o
diff --git a/drivers/soc/rockchip/grf.c b/drivers/soc/rockchip/grf.c
new file mode 100644
index 000000000000..d61db34ad6dd
--- /dev/null
+++ b/drivers/soc/rockchip/grf.c
@@ -0,0 +1,134 @@
+/*
+ * Rockchip Generic Register Files setup
+ *
+ * Copyright (c) 2016 Heiko Stuebner <heiko@sntech.de>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/err.h>
+#include <linux/mfd/syscon.h>
+#include <linux/of_device.h>
+#include <linux/platform_device.h>
+#include <linux/regmap.h>
+
+#define HIWORD_UPDATE(val, mask, shift) \
+		((val) << (shift) | (mask) << ((shift) + 16))
+
+struct rockchip_grf_value {
+	const char *desc;
+	u32 reg;
+	u32 val;
+};
+
+struct rockchip_grf_info {
+	const struct rockchip_grf_value *values;
+	int num_values;
+};
+
+#define RK3036_GRF_SOC_CON0		0x140
+
+static const struct rockchip_grf_value rk3036_defaults[] __initconst = {
+	/*
+	 * Disable auto jtag/sdmmc switching that causes issues with the
+	 * clock-framework and the mmc controllers making them unreliable.
+	 */
+	{ "jtag switching", RK3036_GRF_SOC_CON0, HIWORD_UPDATE(0, 1, 11) },
+};
+
+static const struct rockchip_grf_info rk3036_grf __initconst = {
+	.values = rk3036_defaults,
+	.num_values = ARRAY_SIZE(rk3036_defaults),
+};
+
+#define RK3288_GRF_SOC_CON0		0x244
+
+static const struct rockchip_grf_value rk3288_defaults[] __initconst = {
+	{ "jtag switching", RK3288_GRF_SOC_CON0, HIWORD_UPDATE(0, 1, 12) },
+};
+
+static const struct rockchip_grf_info rk3288_grf __initconst = {
+	.values = rk3288_defaults,
+	.num_values = ARRAY_SIZE(rk3288_defaults),
+};
+
+#define RK3368_GRF_SOC_CON15		0x43c
+
+static const struct rockchip_grf_value rk3368_defaults[] __initconst = {
+	{ "jtag switching", RK3368_GRF_SOC_CON15, HIWORD_UPDATE(0, 1, 13) },
+};
+
+static const struct rockchip_grf_info rk3368_grf __initconst = {
+	.values = rk3368_defaults,
+	.num_values = ARRAY_SIZE(rk3368_defaults),
+};
+
+#define RK3399_GRF_SOC_CON7		0xe21c
+
+static const struct rockchip_grf_value rk3399_defaults[] __initconst = {
+	{ "jtag switching", RK3399_GRF_SOC_CON7, HIWORD_UPDATE(0, 1, 12) },
+};
+
+static const struct rockchip_grf_info rk3399_grf __initconst = {
+	.values = rk3399_defaults,
+	.num_values = ARRAY_SIZE(rk3399_defaults),
+};
+
+static const struct of_device_id rockchip_grf_dt_match[] __initconst = {
+	{
+		.compatible = "rockchip,rk3036-grf",
+		.data = (void *)&rk3036_grf,
+	}, {
+		.compatible = "rockchip,rk3288-grf",
+		.data = (void *)&rk3288_grf,
+	}, {
+		.compatible = "rockchip,rk3368-grf",
+		.data = (void *)&rk3368_grf,
+	}, {
+		.compatible = "rockchip,rk3399-grf",
+		.data = (void *)&rk3399_grf,
+	},
+	{ /* sentinel */ },
+};
+
+static int __init rockchip_grf_init(void)
+{
+	const struct rockchip_grf_info *grf_info;
+	const struct of_device_id *match;
+	struct device_node *np;
+	struct regmap *grf;
+	int ret, i;
+
+	np = of_find_matching_node_and_match(NULL, rockchip_grf_dt_match,
+					     &match);
+	if (!np)
+		return -ENODEV;
+	if (!match || !match->data) {
+		pr_err("%s: missing grf data\n", __func__);
+		return -EINVAL;
+	}
+
+	grf_info = match->data;
+
+	grf = syscon_node_to_regmap(np);
+	if (IS_ERR(grf)) {
+		pr_err("%s: could not get grf syscon\n", __func__);
+		return PTR_ERR(grf);
+	}
+
+	for (i = 0; i < grf_info->num_values; i++) {
+		const struct rockchip_grf_value *val = &grf_info->values[i];
+
+		pr_debug("%s: adjusting %s in %#6x to %#10x\n", __func__,
+			val->desc, val->reg, val->val);
+		ret = regmap_write(grf, val->reg, val->val);
+		if (ret < 0)
+			pr_err("%s: write to %#6x failed with %d\n",
+			       __func__, val->reg, ret);
+	}
+
+	return 0;
+}
+postcore_initcall(rockchip_grf_init);