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 <[email protected]> --- --- 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
