drivers/power/reset/ocelot-reset.c

Source file repositories/reference/linux-study-clean/drivers/power/reset/ocelot-reset.c

File Facts

System
Linux kernel
Corpus path
drivers/power/reset/ocelot-reset.c
Extension
.c
Size
3905 bytes
Lines
153
Domain
Driver Families
Bucket
drivers/power
Inferred role
Driver Families: implementation source
Status
source implementation candidate

Why This File Exists

Repeatable hardware-adapter layer. Deep compatibility for every driver is out of scope; this atlas records patterns, probe lifecycles, bus glue, IRQ/DMA usage, and links back to core abstractions.

Dependency Surface

Detected Declarations

Annotated Snippet

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 = {

Annotation

Implementation Notes