[PATCH 1/1] mtd maps - Blackfin Async Flash Maps (try #4): Handle the case where flash memory and ethernet mac/phy are mapped onto the same async bank

From: Bryan Wu
Date: Mon May 19 2008 - 06:32:37 EST


From: Mike Frysinger <vapier.adi@xxxxxxxxx>

[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: Mike Frysinger <vapier.adi@xxxxxxxxx>
Cc: Joern Engel <joern@xxxxxxxxx>
Signed-off-by: Bryan Wu <cooloney@xxxxxxxxxx>
---
drivers/mtd/maps/Kconfig | 11 ++
drivers/mtd/maps/Makefile | 1 +
drivers/mtd/maps/bfin-async-flash.c | 219 +++++++++++++++++++++++++++++++++++
3 files changed, 231 insertions(+), 0 deletions(-)
create mode 100644 drivers/mtd/maps/bfin-async-flash.c

diff --git a/drivers/mtd/maps/Kconfig b/drivers/mtd/maps/Kconfig
index 17bc87a..d4878eb 100644
--- a/drivers/mtd/maps/Kconfig
+++ b/drivers/mtd/maps/Kconfig
@@ -517,6 +517,17 @@ 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
diff --git a/drivers/mtd/maps/Makefile b/drivers/mtd/maps/Makefile
index 957fb5f..4ed1672 100644
--- a/drivers/mtd/maps/Makefile
+++ b/drivers/mtd/maps/Makefile
@@ -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
diff --git a/drivers/mtd/maps/bfin-async-flash.c b/drivers/mtd/maps/bfin-async-flash.c
new file mode 100644
index 0000000..0d3f6e8
--- /dev/null
+++ b/drivers/mtd/maps/bfin-async-flash.c
@@ -0,0 +1,219 @@
+/*
+ * 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@xxxxxxx>
+ * 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 <asm/gpio.h>
+#include <asm/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;
+ u32 flash_ambctl0, flash_ambctl1;
+ u32 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;
+ u16 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;
+ u16 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");
--
1.5.5
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