Unverified Commit f6352424 authored by Mark Brown's avatar Mark Brown
Browse files

regmap: Add RAM backed register map 



Add a register map that is a simple array of memory, for use in
KUnit testing of the framework. This is not exposed in regmap.h
since I can't think of a non-test use case, it is purely for use
internally. To facilitate testing we track if registers have been
read or written to.

Signed-off-by: default avatarMark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20230324-regmap-kunit-v2-1-b208801dc2c8@kernel.org
parent 1e2bae6a

drivers/base/regmap/Kconfig

+3 −0
Original line number Diff line number Diff line
@@ -41,6 +41,9 @@ config REGMAP_MMIO 
config REGMAP_IRQ

	bool



config REGMAP_RAM

	tristate



config REGMAP_SOUNDWIRE

	tristate

	depends on SOUNDWIRE

drivers/base/regmap/Makefile

+1 −0
Original line number Diff line number Diff line
@@ -7,6 +7,7 @@ obj-$(CONFIG_REGMAP) += regcache-rbtree.o regcache-flat.o 
obj-$(CONFIG_DEBUG_FS) += regmap-debugfs.o

obj-$(CONFIG_REGMAP_AC97) += regmap-ac97.o

obj-$(CONFIG_REGMAP_I2C) += regmap-i2c.o

obj-$(CONFIG_REGMAP_RAM) += regmap-ram.o

obj-$(CONFIG_REGMAP_SLIMBUS) += regmap-slimbus.o

obj-$(CONFIG_REGMAP_SPI) += regmap-spi.o

obj-$(CONFIG_REGMAP_SPMI) += regmap-spmi.o

drivers/base/regmap/internal.h

+19 −0
Original line number Diff line number Diff line
@@ -306,4 +306,23 @@ static inline unsigned int regcache_get_index_by_order(const struct regmap *map, 
	return reg >> map->reg_stride_order;

}



struct regmap_ram_data {

	unsigned int *vals;  /* Allocatd by caller */

	bool *read;

	bool *written;

};



/*

 * Create a test register map with data stored in RAM, not intended

 * for practical use.

 */

struct regmap *__regmap_init_ram(const struct regmap_config *config,

				 struct regmap_ram_data *data,

				 struct lock_class_key *lock_key,

				 const char *lock_name);



#define regmap_init_ram(config, data)					\

	__regmap_lockdep_wrapper(__regmap_init_ram, #config, config, data)





#endif

drivers/base/regmap/regmap-ram.c

0 → 100644
+85 −0
Original line number Diff line number Diff line 
// SPDX-License-Identifier: GPL-2.0

//

// Register map access API - Memory region

//

// This is intended for testing only

//

// Copyright (c) 2023, Arm Ltd



#include <linux/clk.h>

#include <linux/err.h>

#include <linux/io.h>

#include <linux/module.h>

#include <linux/regmap.h>

#include <linux/slab.h>

#include <linux/swab.h>



#include "internal.h"



static int regmap_ram_write(void *context, unsigned int reg, unsigned int val)

{

	struct regmap_ram_data *data = context;



	data->vals[reg] = val;

	data->written[reg] = true;



	return 0;

}



static int regmap_ram_read(void *context, unsigned int reg, unsigned int *val)

{

	struct regmap_ram_data *data = context;



	*val = data->vals[reg];

	data->read[reg] = true;



	return 0;

}



static void regmap_ram_free_context(void *context)

{

	struct regmap_ram_data *data = context;



	kfree(data->vals);

	kfree(data->read);

	kfree(data->written);

	kfree(data);

}



static const struct regmap_bus regmap_ram = {

	.fast_io = true,

	.reg_write = regmap_ram_write,

	.reg_read = regmap_ram_read,

	.free_context = regmap_ram_free_context,

};



struct regmap *__regmap_init_ram(const struct regmap_config *config,

				 struct regmap_ram_data *data,

				 struct lock_class_key *lock_key,

				 const char *lock_name)

{

	struct regmap *map;



	if (!config->max_register) {

		pr_crit("No max_register specified for RAM regmap\n");

		return ERR_PTR(-EINVAL);

	}



	data->read = kcalloc(sizeof(bool), config->max_register + 1,

			     GFP_KERNEL);

	if (!data->read)

		return ERR_PTR(-ENOMEM);



	data->written = kcalloc(sizeof(bool), config->max_register + 1,

				GFP_KERNEL);

	if (!data->written)

		return ERR_PTR(-ENOMEM);



	map = __regmap_init(NULL, &regmap_ram, data, config,

			    lock_key, lock_name);



	return map;

}

EXPORT_SYMBOL_GPL(__regmap_init_ram);



MODULE_LICENSE("GPL v2");