Commit 2e3c22f5 authored by Mike Frysinger's avatar Mike Frysinger Committed by David Woodhouse
Browse files

[MTD] [MAPS] Blackfin Async Flash Maps 



Handle the case where flash memory and ethernet mac/phy are mapped onto
the same async bank

[try #4]
 - drop superfluous casts
 - drop SSYNC() when reading from the flash and rewrite
   bfin_copy_from() to be like bfin_copy_to() so that
   we dont have to handle all the aligned/unaligned cases

[try #3] rename bf5xx-flash to bfin-async-flash
 - move all kconfig board settings into board resources
 - fixup casting style according to lkml feedback
 - rewrite driver so that it can handle arbitrary of
   instances according to the declared platform resources

[try #2]
Remove useless SSYNC() as Will said

[try #1]
The BF533-STAMP does this for example.
All board-specific configuration goes in your board resources file.

Signed-off-by: default avatarMike Frysinger <vapier.adi@gmail.com>
Acked-By: default avatarJörn Engel <joern@logfs.org>
Signed-off-by: default avatarBryan Wu <cooloney@kernel.org>
Signed-off-by: default avatarDavid Woodhouse <dwmw2@infradead.org>
parent 71a928c0

drivers/mtd/maps/Kconfig

+11 −0
Original line number Diff line number Diff line
@@ -523,6 +523,17 @@ config MTD_PCMCIA_ANONYMOUS 


	  If unsure, say N.



config MTD_BFIN_ASYNC

	tristate "Blackfin BF533-STAMP Flash Chip Support"

	depends on BFIN533_STAMP && MTD_CFI

	select MTD_PARTITIONS

	default y

	help

	  Map driver which allows for simultaneous utilization of

	  ethernet and CFI parallel flash.



	  If compiled as a module, it will be called bfin-async-flash.



config MTD_UCLINUX

	tristate "Generic uClinux RAM/ROM filesystem support"

	depends on MTD_PARTITIONS && !MMU

drivers/mtd/maps/Makefile

+1 −0
Original line number Diff line number Diff line
@@ -67,3 +67,4 @@ obj-$(CONFIG_MTD_PLATRAM) += plat-ram.o 
obj-$(CONFIG_MTD_OMAP_NOR)	+= omap_nor.o

obj-$(CONFIG_MTD_MTX1)		+= mtx-1_flash.o

obj-$(CONFIG_MTD_INTEL_VR_NOR)	+= intel_vr_nor.o

obj-$(CONFIG_MTD_BFIN_ASYNC)	+= bfin-async-flash.o

drivers/mtd/maps/bfin-async-flash.c

0 → 100644
+219 −0
Original line number Diff line number Diff line 
/*

 * drivers/mtd/maps/bfin-async-flash.c

 *

 * Handle the case where flash memory and ethernet mac/phy are

 * mapped onto the same async bank.  The BF533-STAMP does this

 * for example.  All board-specific configuration goes in your

 * board resources file.

 *

 * Copyright 2000 Nicolas Pitre <nico@cam.org>

 * Copyright 2005-2008 Analog Devices Inc.

 *

 * Enter bugs at http://blackfin.uclinux.org/

 *

 * Licensed under the GPL-2 or later.

 */



#include <linux/init.h>

#include <linux/kernel.h>

#include <linux/module.h>

#include <linux/mtd/mtd.h>

#include <linux/mtd/map.h>

#include <linux/mtd/partitions.h>

#include <linux/mtd/physmap.h>

#include <linux/platform_device.h>

#include <linux/types.h>



#include <asm/blackfin.h>

#include <linux/gpio.h>

#include <linux/io.h>

#include <asm/unaligned.h>



#define pr_devinit(fmt, args...) ({ static const __devinitconst char __fmt[] = fmt; printk(__fmt, ## args); })



#define DRIVER_NAME "bfin-async-flash"



struct async_state {

	struct mtd_info *mtd;

	struct map_info map;

	int enet_flash_pin;

	uint32_t flash_ambctl0, flash_ambctl1;

	uint32_t save_ambctl0, save_ambctl1;

	unsigned long irq_flags;

};



static void switch_to_flash(struct async_state *state)

{

	local_irq_save(state->irq_flags);



	gpio_set_value(state->enet_flash_pin, 0);



	state->save_ambctl0 = bfin_read_EBIU_AMBCTL0();

	state->save_ambctl1 = bfin_read_EBIU_AMBCTL1();

	bfin_write_EBIU_AMBCTL0(state->flash_ambctl0);

	bfin_write_EBIU_AMBCTL1(state->flash_ambctl1);

	SSYNC();

}



static void switch_back(struct async_state *state)

{

	bfin_write_EBIU_AMBCTL0(state->save_ambctl0);

	bfin_write_EBIU_AMBCTL1(state->save_ambctl1);

	SSYNC();



	gpio_set_value(state->enet_flash_pin, 1);



	local_irq_restore(state->irq_flags);

}



static map_word bfin_read(struct map_info *map, unsigned long ofs)

{

	struct async_state *state = (struct async_state *)map->map_priv_1;

	uint16_t word;

	map_word test;



	switch_to_flash(state);



	word = readw(map->virt + ofs);



	switch_back(state);



	test.x[0] = word;

	return test;

}



static void bfin_copy_from(struct map_info *map, void *to, unsigned long from, ssize_t len)

{

	struct async_state *state = (struct async_state *)map->map_priv_1;



	switch_to_flash(state);



	memcpy(to, map->virt + from, len);



	switch_back(state);

}



static void bfin_write(struct map_info *map, map_word d1, unsigned long ofs)

{

	struct async_state *state = (struct async_state *)map->map_priv_1;

	uint16_t d;



	d = d1.x[0];



	switch_to_flash(state);



	writew(d, map->virt + ofs);

	SSYNC();



	switch_back(state);

}



static void bfin_copy_to(struct map_info *map, unsigned long to, const void *from, ssize_t len)

{

	struct async_state *state = (struct async_state *)map->map_priv_1;



	switch_to_flash(state);



	memcpy(map->virt + to, from, len);

	SSYNC();



	switch_back(state);

}



#ifdef CONFIG_MTD_PARTITIONS

static const char *part_probe_types[] = { "cmdlinepart", "RedBoot", NULL };

#endif



static int __devinit bfin_flash_probe(struct platform_device *pdev)

{

	int ret;

	struct physmap_flash_data *pdata = pdev->dev.platform_data;

	struct resource *memory = platform_get_resource(pdev, IORESOURCE_MEM, 0);

	struct resource *flash_ambctl = platform_get_resource(pdev, IORESOURCE_MEM, 1);

	struct async_state *state;



	state = kzalloc(sizeof(*state), GFP_KERNEL);

	if (!state)

		return -ENOMEM;



	state->map.name       = DRIVER_NAME;

	state->map.read       = bfin_read;

	state->map.copy_from  = bfin_copy_from;

	state->map.write      = bfin_write;

	state->map.copy_to    = bfin_copy_to;

	state->map.bankwidth  = pdata->width;

	state->map.size       = memory->end - memory->start + 1;

	state->map.virt       = (void __iomem *)memory->start;

	state->map.phys       = memory->start;

	state->map.map_priv_1 = (unsigned long)state;

	state->enet_flash_pin = platform_get_irq(pdev, 0);

	state->flash_ambctl0  = flash_ambctl->start;

	state->flash_ambctl1  = flash_ambctl->end;



	if (gpio_request(state->enet_flash_pin, DRIVER_NAME)) {

		pr_devinit(KERN_ERR DRIVER_NAME ": Failed to request gpio %d\n", state->enet_flash_pin);

		return -EBUSY;

	}

	gpio_direction_output(state->enet_flash_pin, 1);



	pr_devinit(KERN_NOTICE DRIVER_NAME ": probing %d-bit flash bus\n", state->map.bankwidth * 8);

	state->mtd = do_map_probe(memory->name, &state->map);

	if (!state->mtd)

		return -ENXIO;



#ifdef CONFIG_MTD_PARTITIONS

	ret = parse_mtd_partitions(state->mtd, part_probe_types, &pdata->parts, 0);

	if (ret > 0) {

		pr_devinit(KERN_NOTICE DRIVER_NAME ": Using commandline partition definition\n");

		add_mtd_partitions(state->mtd, pdata->parts, ret);



	} else if (pdata->nr_parts) {

		pr_devinit(KERN_NOTICE DRIVER_NAME ": Using board partition definition\n");

		add_mtd_partitions(state->mtd, pdata->parts, pdata->nr_parts);



	} else

#endif

	{

		pr_devinit(KERN_NOTICE DRIVER_NAME ": no partition info available, registering whole flash at once\n");

		add_mtd_device(state->mtd);

	}



	platform_set_drvdata(pdev, state);



	return 0;

}



static int __devexit bfin_flash_remove(struct platform_device *pdev)

{

	struct async_state *state = platform_get_drvdata(pdev);

	gpio_free(state->enet_flash_pin);

#ifdef CONFIG_MTD_PARTITIONS

	del_mtd_partitions(state->mtd);

#endif

	map_destroy(state->mtd);

	kfree(state);

	return 0;

}



static struct platform_driver bfin_flash_driver = {

	.probe		= bfin_flash_probe,

	.remove		= __devexit_p(bfin_flash_remove),

	.driver		= {

		.name	= DRIVER_NAME,

	},

};



static int __init bfin_flash_init(void)

{

	return platform_driver_register(&bfin_flash_driver);

}

module_init(bfin_flash_init);



static void __exit bfin_flash_exit(void)

{

	platform_driver_unregister(&bfin_flash_driver);

}

module_exit(bfin_flash_exit);



MODULE_LICENSE("GPL");

MODULE_DESCRIPTION("MTD map driver for Blackfins with flash/ethernet on same async bank");

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