Commit 51fd1914 authored by Michael Walle's avatar Michael Walle Committed by Philipp Zabel
Browse files

reset: microchip-sparx5: issue a reset on startup 



Originally this was used in by the switch core driver to issue a reset.
But it turns out, this isn't just a switch core reset but instead it
will reset almost the complete SoC.

Instead of adding almost all devices of the SoC a shared reset line,
issue the reset once early on startup. Keep the reset controller for
backwards compatibility, but make the actual reset a noop.

Suggested-by: default avatarPhilipp Zabel <p.zabel@pengutronix.de>
Signed-off-by: default avatarMichael Walle <michael@walle.cc>
Tested-by: Steen Hegelund <Steen.Hegelund@microchip.com> on Sparx5
Signed-off-by: default avatarPhilipp Zabel <p.zabel@pengutronix.de>
Link: https://lore.kernel.org/r/20220826115607.1148489-2-michael@walle.cc
parent 051d9eb4

drivers/reset/reset-microchip-sparx5.c

+17 −5
Original line number Diff line number Diff line
@@ -33,11 +33,8 @@ static struct regmap_config sparx5_reset_regmap_config = { 
	.reg_stride	= 4,

};



static int sparx5_switch_reset(struct reset_controller_dev *rcdev,

			       unsigned long id)

static int sparx5_switch_reset(struct mchp_reset_context *ctx)

{

	struct mchp_reset_context *ctx =

		container_of(rcdev, struct mchp_reset_context, rcdev);

	u32 val;



	/* Make sure the core is PROTECTED from reset */
@@ -54,8 +51,14 @@ static int sparx5_switch_reset(struct reset_controller_dev *rcdev, 
					1, 100);

}



static int sparx5_reset_noop(struct reset_controller_dev *rcdev,

			     unsigned long id)

{

	return 0;

}



static const struct reset_control_ops sparx5_reset_ops = {

	.reset = sparx5_switch_reset,

	.reset = sparx5_reset_noop,

};



static int mchp_sparx5_map_syscon(struct platform_device *pdev, char *name,
@@ -122,6 +125,11 @@ static int mchp_sparx5_reset_probe(struct platform_device *pdev) 
	ctx->rcdev.of_node = dn;

	ctx->props = device_get_match_data(&pdev->dev);



	/* Issue the reset very early, our actual reset callback is a noop. */

	err = sparx5_switch_reset(ctx);

	if (err)

		return err;



	return devm_reset_controller_register(&pdev->dev, &ctx->rcdev);

}
@@ -163,6 +171,10 @@ static int __init mchp_sparx5_reset_init(void) 
	return platform_driver_register(&mchp_sparx5_reset_driver);

}



/*

 * Because this is a global reset, keep this postcore_initcall() to issue the

 * reset as early as possible during the kernel startup.

 */

postcore_initcall(mchp_sparx5_reset_init);



MODULE_DESCRIPTION("Microchip Sparx5 switch reset driver");