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-rw-r--r--drivers/soc/renesas/rcar-rst.c92
1 files changed, 92 insertions, 0 deletions
diff --git a/drivers/soc/renesas/rcar-rst.c b/drivers/soc/renesas/rcar-rst.c
new file mode 100644
index 000000000000..a6d1c26d3167
--- /dev/null
+++ b/drivers/soc/renesas/rcar-rst.c
@@ -0,0 +1,92 @@
+/*
+ * R-Car Gen1 RESET/WDT, R-Car Gen2, Gen3, and RZ/G RST Driver
+ *
+ * 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/io.h>
+#include <linux/of_address.h>
+#include <linux/soc/renesas/rcar-rst.h>
+
+struct rst_config {
+ unsigned int modemr; /* Mode Monitoring Register Offset */
+};
+
+static const struct rst_config rcar_rst_gen1 __initconst = {
+ .modemr = 0x20,
+};
+
+static const struct rst_config rcar_rst_gen2 __initconst = {
+ .modemr = 0x60,
+};
+
+static const struct of_device_id rcar_rst_matches[] __initconst = {
+ /* RZ/G is handled like R-Car Gen2 */
+ { .compatible = "renesas,r8a7743-rst", .data = &rcar_rst_gen2 },
+ { .compatible = "renesas,r8a7745-rst", .data = &rcar_rst_gen2 },
+ /* R-Car Gen1 */
+ { .compatible = "renesas,r8a7778-reset-wdt", .data = &rcar_rst_gen1 },
+ { .compatible = "renesas,r8a7779-reset-wdt", .data = &rcar_rst_gen1 },
+ /* R-Car Gen2 */
+ { .compatible = "renesas,r8a7790-rst", .data = &rcar_rst_gen2 },
+ { .compatible = "renesas,r8a7791-rst", .data = &rcar_rst_gen2 },
+ { .compatible = "renesas,r8a7792-rst", .data = &rcar_rst_gen2 },
+ { .compatible = "renesas,r8a7793-rst", .data = &rcar_rst_gen2 },
+ { .compatible = "renesas,r8a7794-rst", .data = &rcar_rst_gen2 },
+ /* R-Car Gen3 is handled like R-Car Gen2 */
+ { .compatible = "renesas,r8a7795-rst", .data = &rcar_rst_gen2 },
+ { .compatible = "renesas,r8a7796-rst", .data = &rcar_rst_gen2 },
+ { /* sentinel */ }
+};
+
+static void __iomem *rcar_rst_base __initdata;
+static u32 saved_mode __initdata;
+
+static int __init rcar_rst_init(void)
+{
+ const struct of_device_id *match;
+ const struct rst_config *cfg;
+ struct device_node *np;
+ void __iomem *base;
+ int error = 0;
+
+ np = of_find_matching_node_and_match(NULL, rcar_rst_matches, &match);
+ if (!np)
+ return -ENODEV;
+
+ base = of_iomap(np, 0);
+ if (!base) {
+ pr_warn("%s: Cannot map regs\n", np->full_name);
+ error = -ENOMEM;
+ goto out_put;
+ }
+
+ rcar_rst_base = base;
+ cfg = match->data;
+ saved_mode = ioread32(base + cfg->modemr);
+
+ pr_debug("%s: MODE = 0x%08x\n", np->full_name, saved_mode);
+
+out_put:
+ of_node_put(np);
+ return error;
+}
+
+int __init rcar_rst_read_mode_pins(u32 *mode)
+{
+ int error;
+
+ if (!rcar_rst_base) {
+ error = rcar_rst_init();
+ if (error)
+ return error;
+ }
+
+ *mode = saved_mode;
+ return 0;
+}