Add DT fixup code to add a reset-controller node for the r8a7791 RST
module if it's not yet present.
This allows the R-Car Gen2 clock driver to use the RST driver to obtain
the value of the mode pins, instead of reading from a hardcoded address
in rcar_gen2_read_mode_pins(), while providing backward compatibility
with old DTBs.
Signed-off-by: Geert Uytterhoeven <geert+renesas@xxxxxxxxx>
---
---
drivers/soc/renesas/Makefile | 4 +
drivers/soc/renesas/renesas-dt-fixup.c | 159 +++++++++++++++++++++++++++++++++
2 files changed, 163 insertions(+)
create mode 100644 drivers/soc/renesas/renesas-dt-fixup.c
diff --git a/drivers/soc/renesas/Makefile b/drivers/soc/renesas/Makefile
index 0d732ff893dd8fba..e5f4454821ca6f63 100644
--- a/drivers/soc/renesas/Makefile
+++ b/drivers/soc/renesas/Makefile
@@ -1,3 +1,7 @@
+# FIXME Depend on new Kconfig symbol CONFIG_ARCH_RENESAS_LEGACY
+# FIXME Needs OF_DYNAMIC
+obj-$(CONFIG_ARCH_RENESAS) += renesas-dt-fixup.o
+
obj-$(CONFIG_ARCH_RCAR_GEN1) += rcar-rst.o
obj-$(CONFIG_ARCH_RCAR_GEN2) += rcar-rst.o
obj-$(CONFIG_ARCH_R8A7795) += rcar-rst.o
diff --git a/drivers/soc/renesas/renesas-dt-fixup.c b/drivers/soc/renesas/renesas-dt-fixup.c
new file mode 100644
index 0000000000000000..83c9ca6b44f8136c
--- /dev/null
+++ b/drivers/soc/renesas/renesas-dt-fixup.c
@@ -0,0 +1,159 @@
+/*
+ * Renesas DT Fixup Code
+ *
+ * Provide backwards compatibility with old DTBs by updating the DT
+ *
+ * Copyright (C) 2016 Glider bvba
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License. See the file "COPYING" in the main directory of this archive
+ * for more details.
+ */
+
+#include <linux/err.h>
+#include <linux/init.h>
+#include <linux/io.h>
+#include <linux/kernel.h>
+#include <linux/of.h>
+#include <linux/slab.h>
+
+#define RST_BASE 0xe6160000
+#define RST_SIZE 0x0100 /* R-Car Gen2 */
+
+static struct property rst_compatible = {
+ .name = "compatible",
+};
+
+static __be32 rst_reg_values[4] = {
+ cpu_to_be32(0),
+ cpu_to_be32(RST_BASE),
+ cpu_to_be32(0),
+ cpu_to_be32(RST_SIZE),
+};
+
+static struct property rst_name = {
+ .name = "name",
+ .length = sizeof("reset-controller"),
+ .value = "reset-controller",
+};
+
+static struct property rst_reg = {
+ .name = "reg",
+ .length = sizeof(rst_reg_values),
+ .value = rst_reg_values,
+};
+
+static int __init add_rst(struct device_node *parent, const char *path,
+ char *compatible)
+{
+ struct property *prop[] = { &rst_compatible, &rst_name, &rst_reg };
+ struct device_node *np;
+ char *full_name;
+ unsigned int i;
+ int error;
+
+ pr_debug("Adding RST node %s\n", compatible);
+ np = kzalloc(sizeof(*np), GFP_KERNEL);
+ if (!np)
+ return -ENOMEM;
+
+ np->name = kasprintf(GFP_KERNEL, "%s@%x", (char *)rst_name.value,
+ RST_BASE);
+ full_name = kasprintf(GFP_KERNEL, "%s/%s", path, np->name);
+ np->full_name = full_name;
+ np->parent = parent;
+
+ of_node_set_flag(np, OF_DYNAMIC);
+ of_node_init(np);
+
+ error = of_attach_node(np);
+ if (error) {
+ pr_err("%s: of_attach_node() %s failed %d\n", __func__,
+ np->name, error);
+ kfree(np);
+ return error;
+ }
+
+ rst_compatible.value = compatible;
+ rst_compatible.length = strlen(rst_compatible.value) + 1;
+
+ for (i = 0; i < ARRAY_SIZE(prop); i++) {
+ error = of_add_property(np, prop[i]);
+ if (error)
+ pr_err("%s: of_add_property() %s/%s failed %d\n",
+ __func__, np->name, prop[i]->name, error);
+ }
+
+ return 0;
+}
+
+static int __init add_sysc(struct device_node *parent, const char *path,
+ char *compatible)
+{
+ pr_debug("NOT YET adding SYSC node %s\n", compatible);
+ return 0;
+}
+
+static const struct of_device_id renesas_matches[] __initconst = {
+ { .compatible = "renesas,r8a7791", },
+ { /* sentinel */ }
+};
+
+static int __init renesas_dt_fixup(void)
+{
+ const struct of_device_id *match;
+ struct device_node *np, *parent;
+ const char *parent_path;
+ char *compatible;
+
+ np = of_find_node_by_path("/");
+ if (!np)
+ return -ENODEV;
+
+ for (match = renesas_matches; match->compatible[0]; match++)
+ if (of_device_is_compatible(np, match->compatible))
+ break;
+ of_node_put(np);
+
+ if (!match->compatible[0])
+ return -ENODEV;
+
+ /* Find the main SoC bus node */
+ np = of_find_compatible_node(NULL, NULL, "arm,gic-400");
+ if (!np) {
+ pr_warn("%s: Cannot find %s\n", __func__, "arm,gic-400");
+ return -ENODEV;
+ }
+
+ parent = of_get_parent(np);
+ of_node_put(np);
+ if (!parent) {
+ pr_warn("%s: Cannot find GIC parent\n", __func__);
+ return -ENODEV;
+ }
+
+ parent_path = parent->full_name;
+ /* Prevent double leading slash */
+ if (!parent_path[1])
+ parent_path++;
+
+ compatible = kasprintf(GFP_KERNEL, "%s-rst", match->compatible);
+ if (of_find_compatible_node(NULL, NULL, compatible)) {
+ pr_debug("%s: RST node %s present\n", __func__, compatible);
+ kfree(compatible);
+ } else {
+ add_rst(parent, parent_path, compatible);
+ }
+
+ compatible = kasprintf(GFP_KERNEL, "%s-sysc", match->compatible);
+ if (of_find_compatible_node(NULL, NULL, compatible)) {
+ pr_debug("%s: SYSC node %s present\n", __func__, compatible);
+ kfree(compatible);
+ } else {
+ add_sysc(parent, parent_path, compatible);
+ }
+
+ of_node_put(parent);
+ return 0;
+}
+early_initcall(renesas_dt_fixup);
--
1.9.1
