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path: root/drivers/power/reset/ocelot-reset.c
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Diffstat (limited to 'drivers/power/reset/ocelot-reset.c')
-rw-r--r--drivers/power/reset/ocelot-reset.c152
1 files changed, 152 insertions, 0 deletions
diff --git a/drivers/power/reset/ocelot-reset.c b/drivers/power/reset/ocelot-reset.c
new file mode 100644
index 0000000000..56be64decf
--- /dev/null
+++ b/drivers/power/reset/ocelot-reset.c
@@ -0,0 +1,152 @@
+// SPDX-License-Identifier: (GPL-2.0 OR MIT)
+/*
+ * Microsemi MIPS SoC reset driver
+ *
+ * License: Dual MIT/GPL
+ * Copyright (c) 2017 Microsemi Corporation
+ */
+#include <linux/delay.h>
+#include <linux/io.h>
+#include <linux/notifier.h>
+#include <linux/mod_devicetable.h>
+#include <linux/mfd/syscon.h>
+#include <linux/platform_device.h>
+#include <linux/property.h>
+#include <linux/reboot.h>
+#include <linux/regmap.h>
+
+struct reset_props {
+ const char *syscon;
+ u32 protect_reg;
+ u32 vcore_protect;
+ u32 if_si_owner_bit;
+};
+
+struct ocelot_reset_context {
+ void __iomem *base;
+ struct regmap *cpu_ctrl;
+ const struct reset_props *props;
+ struct notifier_block restart_handler;
+};
+
+#define BIT_OFF_INVALID 32
+
+#define SOFT_CHIP_RST BIT(0)
+
+#define ICPU_CFG_CPU_SYSTEM_CTRL_GENERAL_CTRL 0x24
+#define IF_SI_OWNER_MASK GENMASK(1, 0)
+#define IF_SI_OWNER_SISL 0
+#define IF_SI_OWNER_SIBM 1
+#define IF_SI_OWNER_SIMC 2
+
+static int ocelot_restart_handle(struct notifier_block *this,
+ unsigned long mode, void *cmd)
+{
+ struct ocelot_reset_context *ctx = container_of(this, struct
+ ocelot_reset_context,
+ restart_handler);
+ u32 if_si_owner_bit = ctx->props->if_si_owner_bit;
+
+ /* Make sure the core is not protected from reset */
+ regmap_update_bits(ctx->cpu_ctrl, ctx->props->protect_reg,
+ ctx->props->vcore_protect, 0);
+
+ /* Make the SI back to boot mode */
+ if (if_si_owner_bit != BIT_OFF_INVALID)
+ regmap_update_bits(ctx->cpu_ctrl,
+ ICPU_CFG_CPU_SYSTEM_CTRL_GENERAL_CTRL,
+ IF_SI_OWNER_MASK << if_si_owner_bit,
+ IF_SI_OWNER_SIBM << if_si_owner_bit);
+
+ pr_emerg("Resetting SoC\n");
+
+ writel(SOFT_CHIP_RST, ctx->base);
+
+ pr_emerg("Unable to restart system\n");
+ return NOTIFY_DONE;
+}
+
+static int ocelot_reset_probe(struct platform_device *pdev)
+{
+ struct ocelot_reset_context *ctx;
+ struct device *dev = &pdev->dev;
+ int err;
+
+ ctx = devm_kzalloc(&pdev->dev, sizeof(*ctx), GFP_KERNEL);
+ if (!ctx)
+ return -ENOMEM;
+
+ ctx->base = devm_platform_ioremap_resource(pdev, 0);
+ if (IS_ERR(ctx->base))
+ return PTR_ERR(ctx->base);
+
+ ctx->props = device_get_match_data(dev);
+
+ ctx->cpu_ctrl = syscon_regmap_lookup_by_compatible(ctx->props->syscon);
+ if (IS_ERR(ctx->cpu_ctrl)) {
+ dev_err(dev, "No syscon map: %s\n", ctx->props->syscon);
+ return PTR_ERR(ctx->cpu_ctrl);
+ }
+
+ ctx->restart_handler.notifier_call = ocelot_restart_handle;
+ ctx->restart_handler.priority = 192;
+ err = register_restart_handler(&ctx->restart_handler);
+ if (err)
+ dev_err(dev, "can't register restart notifier (err=%d)\n", err);
+
+ return err;
+}
+
+static const struct reset_props reset_props_jaguar2 = {
+ .syscon = "mscc,ocelot-cpu-syscon",
+ .protect_reg = 0x20,
+ .vcore_protect = BIT(2),
+ .if_si_owner_bit = 6,
+};
+
+static const struct reset_props reset_props_luton = {
+ .syscon = "mscc,ocelot-cpu-syscon",
+ .protect_reg = 0x20,
+ .vcore_protect = BIT(2),
+ .if_si_owner_bit = BIT_OFF_INVALID, /* n/a */
+};
+
+static const struct reset_props reset_props_ocelot = {
+ .syscon = "mscc,ocelot-cpu-syscon",
+ .protect_reg = 0x20,
+ .vcore_protect = BIT(2),
+ .if_si_owner_bit = 4,
+};
+
+static const struct reset_props reset_props_sparx5 = {
+ .syscon = "microchip,sparx5-cpu-syscon",
+ .protect_reg = 0x84,
+ .vcore_protect = BIT(10),
+ .if_si_owner_bit = 6,
+};
+
+static const struct of_device_id ocelot_reset_of_match[] = {
+ {
+ .compatible = "mscc,jaguar2-chip-reset",
+ .data = &reset_props_jaguar2
+ }, {
+ .compatible = "mscc,luton-chip-reset",
+ .data = &reset_props_luton
+ }, {
+ .compatible = "mscc,ocelot-chip-reset",
+ .data = &reset_props_ocelot
+ }, {
+ .compatible = "microchip,sparx5-chip-reset",
+ .data = &reset_props_sparx5
+ },
+ { /*sentinel*/ }
+};
+
+static struct platform_driver ocelot_reset_driver = {
+ .probe = ocelot_reset_probe,
+ .driver = {
+ .name = "ocelot-chip-reset",
+ .of_match_table = ocelot_reset_of_match,
+ },
+};
+builtin_platform_driver(ocelot_reset_driver);