Commit 781f60e4 authored by Conor Dooley's avatar Conor Dooley
Browse files

reset: mpfs: add non-auxiliary bus probing 



While the auxiliary bus was a nice bandaid, and meant that re-writing
the representation of the clock regions in devicetree was not required,
it has run its course. The "mss_top_sysreg" region that contains the
clock and reset regions, also contains pinctrl and an interrupt
controller, so the time has come rewrite the devicetree and probe the
reset controller from an mfd devicetree node, rather than implement
those drivers using the auxiliary bus. Wanting to avoid propagating this
naive/incorrect description of the hardware to the new pic64gx SoC is a
major motivating factor here.

Reviewed-by: default avatarPhilipp Zabel <p.zabel@pengutronix.de>
Acked-by: default avatarPhilipp Zabel <p.zabel@pengutronix.de>
Signed-off-by: default avatarConor Dooley <conor.dooley@microchip.com>
parent bab55c25

drivers/clk/microchip/clk-mpfs.c

+2 −2
Original line number Diff line number Diff line
@@ -38,7 +38,7 @@ static const struct regmap_config mpfs_clk_regmap_config = { 
	.reg_stride = 4,

	.val_bits = 32,

	.val_format_endian = REGMAP_ENDIAN_LITTLE,

	.max_register = REG_SUBBLK_CLOCK_CR,

	.max_register = REG_SUBBLK_RESET_CR,

};



/*
@@ -502,7 +502,7 @@ static inline int mpfs_clk_old_format_probe(struct mpfs_clock_data *clk_data, 
	if (IS_ERR(clk_data->regmap))

		return PTR_ERR(clk_data->regmap);



	return mpfs_reset_controller_register(dev, clk_data->base + REG_SUBBLK_RESET_CR);

	return mpfs_reset_controller_register(dev, clk_data->regmap);

}



static int mpfs_clk_probe(struct platform_device *pdev)

drivers/reset/Kconfig

+1 −0
Original line number Diff line number Diff line
@@ -200,6 +200,7 @@ config RESET_PISTACHIO 
config RESET_POLARFIRE_SOC

	bool "Microchip PolarFire SoC (MPFS) Reset Driver"

	depends on MCHP_CLK_MPFS

	depends on MFD_SYSCON

	select AUXILIARY_BUS

	default MCHP_CLK_MPFS

	help

drivers/reset/reset-mpfs.c

+55 −36
Original line number Diff line number Diff line
@@ -9,11 +9,13 @@ 
#include <linux/auxiliary_bus.h>

#include <linux/delay.h>

#include <linux/io.h>

#include <linux/mfd/syscon.h>

#include <linux/module.h>

#include <linux/of.h>

#include <linux/platform_device.h>

#include <linux/slab.h>

#include <linux/regmap.h>

#include <linux/reset-controller.h>

#include <linux/slab.h>

#include <dt-bindings/clock/microchip,mpfs-clock.h>

#include <soc/microchip/mpfs.h>
@@ -27,11 +29,10 @@ 
#define MPFS_SLEEP_MIN_US	100

#define MPFS_SLEEP_MAX_US	200



/* block concurrent access to the soft reset register */

static DEFINE_SPINLOCK(mpfs_reset_lock);

#define REG_SUBBLK_RESET_CR	0x88u



struct mpfs_reset {

	void __iomem *base;

	struct regmap *regmap;

	struct reset_controller_dev rcdev;

};
@@ -46,41 +47,25 @@ static inline struct mpfs_reset *to_mpfs_reset(struct reset_controller_dev *rcde 
static int mpfs_assert(struct reset_controller_dev *rcdev, unsigned long id)

{

	struct mpfs_reset *rst = to_mpfs_reset(rcdev);

	unsigned long flags;

	u32 reg;



	spin_lock_irqsave(&mpfs_reset_lock, flags);



	reg = readl(rst->base);

	reg |= BIT(id);

	writel(reg, rst->base);



	spin_unlock_irqrestore(&mpfs_reset_lock, flags);

	return regmap_set_bits(rst->regmap, REG_SUBBLK_RESET_CR, BIT(id));



	return 0;

}



static int mpfs_deassert(struct reset_controller_dev *rcdev, unsigned long id)

{

	struct mpfs_reset *rst = to_mpfs_reset(rcdev);

	unsigned long flags;

	u32 reg;



	spin_lock_irqsave(&mpfs_reset_lock, flags);



	reg = readl(rst->base);

	reg &= ~BIT(id);

	writel(reg, rst->base);

	return regmap_clear_bits(rst->regmap, REG_SUBBLK_RESET_CR, BIT(id));



	spin_unlock_irqrestore(&mpfs_reset_lock, flags);



	return 0;

}



static int mpfs_status(struct reset_controller_dev *rcdev, unsigned long id)

{

	struct mpfs_reset *rst = to_mpfs_reset(rcdev);

	u32 reg = readl(rst->base);

	u32 reg;



	regmap_read(rst->regmap, REG_SUBBLK_RESET_CR, &reg);



	/*

	 * It is safe to return here as MPFS_NUM_RESETS makes sure the sign bit
@@ -130,23 +115,58 @@ static int mpfs_reset_xlate(struct reset_controller_dev *rcdev, 
	return index - MPFS_PERIPH_OFFSET;

}



static int mpfs_reset_probe(struct auxiliary_device *adev,

static int mpfs_reset_mfd_probe(struct platform_device *pdev)

{

	struct reset_controller_dev *rcdev;

	struct device *dev = &pdev->dev;

	struct mpfs_reset *rst;



	rst = devm_kzalloc(dev, sizeof(*rst), GFP_KERNEL);

	if (!rst)

		return -ENOMEM;



	rcdev = &rst->rcdev;

	rcdev->dev = dev;

	rcdev->ops = &mpfs_reset_ops;



	rcdev->of_node = pdev->dev.parent->of_node;

	rcdev->of_reset_n_cells = 1;

	rcdev->of_xlate = mpfs_reset_xlate;

	rcdev->nr_resets = MPFS_NUM_RESETS;



	rst->regmap = device_node_to_regmap(pdev->dev.parent->of_node);

	if (IS_ERR(rst->regmap))

		return dev_err_probe(dev, PTR_ERR(rst->regmap),

				     "Failed to find syscon regmap\n");



	return devm_reset_controller_register(dev, rcdev);

}



static struct platform_driver mpfs_reset_mfd_driver = {

	.probe = mpfs_reset_mfd_probe,

	.driver = {

		.name = "mpfs-reset",

	},

};

module_platform_driver(mpfs_reset_mfd_driver);



static int mpfs_reset_adev_probe(struct auxiliary_device *adev,

				 const struct auxiliary_device_id *id)

{

	struct device *dev = &adev->dev;

	struct reset_controller_dev *rcdev;

	struct device *dev = &adev->dev;

	struct mpfs_reset *rst;



	rst = devm_kzalloc(dev, sizeof(*rst), GFP_KERNEL);

	if (!rst)

		return -ENOMEM;



	rst->base = (void __iomem *)adev->dev.platform_data;

	rst->regmap = (struct regmap *)adev->dev.platform_data;



	rcdev = &rst->rcdev;

	rcdev->dev = dev;

	rcdev->dev->parent = dev->parent;

	rcdev->ops = &mpfs_reset_ops;



	rcdev->of_node = dev->parent->of_node;

	rcdev->of_reset_n_cells = 1;

	rcdev->of_xlate = mpfs_reset_xlate;
@@ -155,12 +175,11 @@ static int mpfs_reset_probe(struct auxiliary_device *adev, 
	return devm_reset_controller_register(dev, rcdev);

}



int mpfs_reset_controller_register(struct device *clk_dev, void __iomem *base)

int mpfs_reset_controller_register(struct device *clk_dev, struct regmap *map)

{

	struct auxiliary_device *adev;



	adev = devm_auxiliary_device_create(clk_dev, "reset-mpfs",

					    (__force void *)base);

	adev = devm_auxiliary_device_create(clk_dev, "reset-mpfs", (void *)map);

	if (!adev)

		return -ENODEV;
@@ -176,12 +195,12 @@ static const struct auxiliary_device_id mpfs_reset_ids[] = { 
};

MODULE_DEVICE_TABLE(auxiliary, mpfs_reset_ids);



static struct auxiliary_driver mpfs_reset_driver = {

	.probe		= mpfs_reset_probe,

static struct auxiliary_driver mpfs_reset_aux_driver = {

	.probe		= mpfs_reset_adev_probe,

	.id_table	= mpfs_reset_ids,

};



module_auxiliary_driver(mpfs_reset_driver);

module_auxiliary_driver(mpfs_reset_aux_driver);



MODULE_DESCRIPTION("Microchip PolarFire SoC Reset Driver");

MODULE_AUTHOR("Conor Dooley <conor.dooley@microchip.com>");

include/soc/microchip/mpfs.h

+2 −1
Original line number Diff line number Diff line
@@ -14,6 +14,7 @@ 


#include <linux/types.h>

#include <linux/of_device.h>

#include <linux/regmap.h>



struct mpfs_sys_controller;
@@ -44,7 +45,7 @@ struct mtd_info *mpfs_sys_controller_get_flash(struct mpfs_sys_controller *mpfs_ 


#if IS_ENABLED(CONFIG_MCHP_CLK_MPFS)

#if IS_ENABLED(CONFIG_RESET_POLARFIRE_SOC)

int mpfs_reset_controller_register(struct device *clk_dev, void __iomem *base);

int mpfs_reset_controller_register(struct device *clk_dev, struct regmap *map);

#else

static inline int mpfs_reset_controller_register(struct device *clk_dev, void __iomem *base) { return 0; }

#endif /* if IS_ENABLED(CONFIG_RESET_POLARFIRE_SOC) */