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Diffstat (limited to 'drivers/soc/renesas/rcar-rst.c')
-rw-r--r--drivers/soc/renesas/rcar-rst.c171
1 files changed, 171 insertions, 0 deletions
diff --git a/drivers/soc/renesas/rcar-rst.c b/drivers/soc/renesas/rcar-rst.c
new file mode 100644
index 000000000..e1c7e91f5
--- /dev/null
+++ b/drivers/soc/renesas/rcar-rst.c
@@ -0,0 +1,171 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * R-Car Gen1 RESET/WDT, R-Car Gen2, Gen3, and RZ/G RST Driver
+ *
+ * Copyright (C) 2016 Glider bvba
+ */
+
+#include <linux/err.h>
+#include <linux/io.h>
+#include <linux/of_address.h>
+#include <linux/soc/renesas/rcar-rst.h>
+
+#define WDTRSTCR_RESET 0xA55A0002
+#define WDTRSTCR 0x0054
+
+#define CR7BAR 0x0070
+#define CR7BAREN BIT(4)
+#define CR7BAR_MASK 0xFFFC0000
+
+static void __iomem *rcar_rst_base;
+static u32 saved_mode __initdata;
+static int (*rcar_rst_set_rproc_boot_addr_func)(u64 boot_addr);
+
+static int rcar_rst_enable_wdt_reset(void __iomem *base)
+{
+ iowrite32(WDTRSTCR_RESET, base + WDTRSTCR);
+ return 0;
+}
+
+/*
+ * Most of the R-Car Gen3 SoCs have an ARM Realtime Core.
+ * Firmware boot address has to be set in CR7BAR before
+ * starting the realtime core.
+ * Boot address must be aligned on a 256k boundary.
+ */
+static int rcar_rst_set_gen3_rproc_boot_addr(u64 boot_addr)
+{
+ if (boot_addr & ~(u64)CR7BAR_MASK) {
+ pr_err("Invalid boot address got %llx\n", boot_addr);
+ return -EINVAL;
+ }
+
+ iowrite32(boot_addr, rcar_rst_base + CR7BAR);
+ iowrite32(boot_addr | CR7BAREN, rcar_rst_base + CR7BAR);
+
+ return 0;
+}
+
+struct rst_config {
+ unsigned int modemr; /* Mode Monitoring Register Offset */
+ int (*configure)(void __iomem *base); /* Platform specific config */
+ int (*set_rproc_boot_addr)(u64 boot_addr);
+};
+
+static const struct rst_config rcar_rst_gen1 __initconst = {
+ .modemr = 0x20,
+};
+
+static const struct rst_config rcar_rst_gen2 __initconst = {
+ .modemr = 0x60,
+ .configure = rcar_rst_enable_wdt_reset,
+};
+
+static const struct rst_config rcar_rst_gen3 __initconst = {
+ .modemr = 0x60,
+ .set_rproc_boot_addr = rcar_rst_set_gen3_rproc_boot_addr,
+};
+
+static const struct rst_config rcar_rst_gen4 __initconst = {
+ .modemr = 0x00, /* MODEMR0 and it has CPG related bits */
+};
+
+static const struct of_device_id rcar_rst_matches[] __initconst = {
+ /* RZ/G1 is handled like R-Car Gen2 */
+ { .compatible = "renesas,r8a7742-rst", .data = &rcar_rst_gen2 },
+ { .compatible = "renesas,r8a7743-rst", .data = &rcar_rst_gen2 },
+ { .compatible = "renesas,r8a7744-rst", .data = &rcar_rst_gen2 },
+ { .compatible = "renesas,r8a7745-rst", .data = &rcar_rst_gen2 },
+ { .compatible = "renesas,r8a77470-rst", .data = &rcar_rst_gen2 },
+ /* RZ/G2 is handled like R-Car Gen3 */
+ { .compatible = "renesas,r8a774a1-rst", .data = &rcar_rst_gen3 },
+ { .compatible = "renesas,r8a774b1-rst", .data = &rcar_rst_gen3 },
+ { .compatible = "renesas,r8a774c0-rst", .data = &rcar_rst_gen3 },
+ { .compatible = "renesas,r8a774e1-rst", .data = &rcar_rst_gen3 },
+ /* 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 */
+ { .compatible = "renesas,r8a7795-rst", .data = &rcar_rst_gen3 },
+ { .compatible = "renesas,r8a7796-rst", .data = &rcar_rst_gen3 },
+ { .compatible = "renesas,r8a77961-rst", .data = &rcar_rst_gen3 },
+ { .compatible = "renesas,r8a77965-rst", .data = &rcar_rst_gen3 },
+ { .compatible = "renesas,r8a77970-rst", .data = &rcar_rst_gen3 },
+ { .compatible = "renesas,r8a77980-rst", .data = &rcar_rst_gen3 },
+ { .compatible = "renesas,r8a77990-rst", .data = &rcar_rst_gen3 },
+ { .compatible = "renesas,r8a77995-rst", .data = &rcar_rst_gen3 },
+ /* R-Car Gen4 */
+ { .compatible = "renesas,r8a779a0-rst", .data = &rcar_rst_gen4 },
+ { .compatible = "renesas,r8a779f0-rst", .data = &rcar_rst_gen4 },
+ { .compatible = "renesas,r8a779g0-rst", .data = &rcar_rst_gen4 },
+ { /* sentinel */ }
+};
+
+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("%pOF: Cannot map regs\n", np);
+ error = -ENOMEM;
+ goto out_put;
+ }
+
+ rcar_rst_base = base;
+ cfg = match->data;
+ rcar_rst_set_rproc_boot_addr_func = cfg->set_rproc_boot_addr;
+
+ saved_mode = ioread32(base + cfg->modemr);
+ if (cfg->configure) {
+ error = cfg->configure(base);
+ if (error) {
+ pr_warn("%pOF: Cannot run SoC specific configuration\n",
+ np);
+ goto out_put;
+ }
+ }
+
+ pr_debug("%pOF: MODE = 0x%08x\n", np, 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;
+}
+
+int rcar_rst_set_rproc_boot_addr(u64 boot_addr)
+{
+ if (!rcar_rst_set_rproc_boot_addr_func)
+ return -EIO;
+
+ return rcar_rst_set_rproc_boot_addr_func(boot_addr);
+}
+EXPORT_SYMBOL_GPL(rcar_rst_set_rproc_boot_addr);