ENGR00244769-1 [NOR FLASH]-Improve WEIM NOR speed

Increase the NOR flash read speed.
Added weimnor driver to use cached (and page mode) reads.

Signed-off-by: Oliver Brown <oliver.brown@freescale.com>

3 files changed, 309 insertions, 0 deletions

diff --git a/drivers/mtd/maps/Kconfig b/drivers/mtd/maps/Kconfig
index c0c328c5b133..96e6f186bf57 100644
--- a/drivers/mtd/maps/Kconfig
+++ b/drivers/mtd/maps/Kconfig
@@ -162,6 +162,15 @@ config MTD_PXA2XX
 	help
 	  This provides a driver for the NOR flash attached to a PXA2xx chip.
 
+config MTD_IMX6X_WEIMNOR
+	tristate "CFI Flash device mapped on iMX6x based boards"
+	depends on MTD_CFI || MTD_JEDECPROBE || MTD_ROM || MTD_LPDDR
+	help
+	  This provides a driver for the WEIM (Parallel) NOR flash attached to
+	  an iMX6x chip. This driver provides a cached read to take advantage
+	  of paged reads by using memcopy.  If you have a board such as the
+	  SabreAI select 'Y' to use the NOR flash chips on it.
+
 config MTD_OCTAGON
 	tristate "JEDEC Flash device mapped on Octagon 5066 SBC"
 	depends on X86 && MTD_JEDEC && MTD_COMPLEX_MAPPINGS
diff --git a/drivers/mtd/maps/Makefile b/drivers/mtd/maps/Makefile
index cb48b11affff..8f437a0b828d 100644
--- a/drivers/mtd/maps/Makefile
+++ b/drivers/mtd/maps/Makefile
@@ -18,6 +18,7 @@ obj-$(CONFIG_MTD_ICHXROM)	+= ichxrom.o
 obj-$(CONFIG_MTD_CK804XROM)	+= ck804xrom.o
 obj-$(CONFIG_MTD_TSUNAMI)	+= tsunami_flash.o
 obj-$(CONFIG_MTD_PXA2XX)	+= pxa2xx-flash.o
+obj-$(CONFIG_MTD_IMX6X_WEIMNOR) += imx6x-weimnor.o
 obj-$(CONFIG_MTD_MBX860)	+= mbx860.o
 obj-$(CONFIG_MTD_CEIVA)		+= ceiva.o
 obj-$(CONFIG_MTD_OCTAGON)	+= octagon-5066.o
diff --git a/drivers/mtd/maps/imx6x-weimnor.c b/drivers/mtd/maps/imx6x-weimnor.c
new file mode 100644
index 000000000000..60a96da32dcf
--- /dev/null
+++ b/drivers/mtd/maps/imx6x-weimnor.c
@@ -0,0 +1,299 @@
+/*
+ * Copyright (C) 2013 Freescale Semiconductor, Inc. All Rights Reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ */
+
+#include <linux/module.h>
+#include <linux/types.h>
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/slab.h>
+#include <linux/device.h>
+#include <linux/platform_device.h>
+#include <linux/mtd/mtd.h>
+#include <linux/mtd/map.h>
+#include <linux/mtd/partitions.h>
+#include <linux/mtd/physmap.h>
+#include <linux/mtd/concat.h>
+#include <linux/io.h>
+
+#include <asm/outercache.h>
+
+#define MAX_RESOURCES		4
+
+struct imx6x_weimnor_info {
+	struct mtd_info         *mtd[MAX_RESOURCES];
+	struct mtd_info         *cmtd;
+	struct map_info         map[MAX_RESOURCES];
+	int                     nr_parts;
+	struct mtd_partition    *parts;
+};
+
+static int imx6x_weimnor_remove(struct platform_device *dev)
+{
+	struct imx6x_weimnor_info *info;
+	int i;
+
+	info = platform_get_drvdata(dev);
+
+	if (info == NULL)
+		return 0;
+
+	platform_set_drvdata(dev, NULL);
+
+	if (info->cmtd) {
+		mtd_device_unregister(info->cmtd);
+		if (info->nr_parts)
+			kfree(info->parts);
+		if (info->cmtd != info->mtd[0])
+			mtd_concat_destroy(info->cmtd);
+	}
+
+	for (i = 0; i < MAX_RESOURCES; i++) {
+		if (info->mtd[i] != NULL)
+			map_destroy(info->mtd[i]);
+		if (info->map[i].cached)
+			iounmap(info->map[i].cached);
+	}
+
+	kfree(info);
+
+	return 0;
+}
+
+static void imx6x_set_vpp(struct map_info *map, int state)
+{
+	struct platform_device *pdev;
+	struct physmap_flash_data *flash;
+
+	pdev = (struct platform_device *)map->map_priv_1;
+	flash = pdev->dev.platform_data;
+
+	if (flash->set_vpp)
+		flash->set_vpp(pdev, state);
+}
+
+#define CACHELINESIZE 32
+static void imx6x_map_inval_cache(struct map_info *map, unsigned long from,
+ssize_t len)
+{
+	unsigned long start;
+	unsigned long end;
+	unsigned long phys_start;
+	unsigned long phys_end;
+
+	if (from > map->size) {
+		start = (unsigned long)map->cached + map->size;
+		phys_start = (unsigned long)map->phys +  map->size;
+	} else {
+		start = (unsigned long)map->cached + from;
+		phys_start = (unsigned long)map->phys + from;
+	}
+
+	if ((from + len)  > map->size) {
+		end = start + map->size;
+		phys_end = phys_start + map->size;
+	} else {
+		end = start + len;
+		phys_end = phys_start + len;
+	}
+
+	start &= ~(CACHELINESIZE - 1);
+	while (start < end) {
+		/* invalidate D cache line */
+		asm volatile ("mcr p15, 0, %0, c7, c6, 1" : : "r" (start));
+		start += CACHELINESIZE;
+	}
+	outer_inv_range(phys_start, phys_end);
+}
+
+static const char *rom_probe_types[] = {
+	"cfi_probe",
+	"jedec_probe",
+	"qinfo_probe",
+	"map_rom",
+	NULL};
+
+static const char *part_probe_types[] = { "cmdlinepart", "RedBoot", "afs",
+	NULL};
+
+static int imx6x_weimnor_probe(struct platform_device *dev)
+{
+	struct physmap_flash_data *flash;
+	struct imx6x_weimnor_info *info;
+	const char **probe_type;
+	int err = 0;
+	int i;
+	int devices_found = 0;
+
+	flash = dev->dev.platform_data;
+	if (flash == NULL)
+		return -ENODEV;
+
+	info = devm_kzalloc(&dev->dev, sizeof(struct imx6x_weimnor_info),
+	       GFP_KERNEL);
+	if (info == NULL) {
+		err = -ENOMEM;
+		goto err_out;
+	}
+
+	if (flash->init) {
+		err = flash->init(dev);
+		if (err)
+			goto err_out;
+	}
+
+	platform_set_drvdata(dev, info);
+
+	for (i = 0; i < dev->num_resources; i++) {
+		printk(KERN_NOTICE
+		       "imx6x-flash (physmap) platform "
+		       "flash device: %.8llx at %.8llx\n",
+		(unsigned long long)resource_size(&dev->resource[i]),
+		(unsigned long long)dev->resource[i].start);
+
+		if (!devm_request_mem_region(&dev->dev,
+		dev->resource[i].start,
+		resource_size(&dev->resource[i]),
+		dev_name(&dev->dev))) {
+			dev_err(&dev->dev, "Could not reserve memory region\n");
+			err = -ENOMEM;
+			goto err_out;
+		}
+
+		info->map[i].name = dev_name(&dev->dev);
+		info->map[i].phys = dev->resource[i].start;
+		info->map[i].size = resource_size(&dev->resource[i]);
+		info->map[i].bankwidth = flash->width;
+		info->map[i].set_vpp = imx6x_set_vpp;
+		info->map[i].pfow_base = 0;
+		info->map[i].map_priv_1 = (unsigned long)dev;
+		info->map[i].virt = devm_ioremap(&dev->dev, info->map[i].phys,
+				    info->map[i].size);
+		if (info->map[i].virt == NULL) {
+			dev_err(&dev->dev, "Failed to ioremap flash region\n");
+			err = -EIO;
+			goto err_out;
+		}
+
+		info->map[i].cached =
+		ioremap_cached(info->map[i].phys, info->map[i].size);
+		if (!info->map[i].cached)
+			printk(KERN_WARNING "Failed to ioremap cached %s\n",
+			info->map[i].name);
+
+		info->map[i].inval_cache = imx6x_map_inval_cache;
+
+		simple_map_init(&info->map[i]);
+		probe_type = rom_probe_types;
+
+		for (; info->mtd[i] == NULL && *probe_type != NULL;
+		      probe_type++)
+			info->mtd[i] = do_map_probe(*probe_type, &info->map[i]);
+
+		if (info->mtd[i] == NULL) {
+			dev_err(&dev->dev, "map_probe failed\n");
+			err = -ENXIO;
+			goto err_out;
+		} else {
+			devices_found++;
+		}
+		info->mtd[i]->owner = THIS_MODULE;
+		info->mtd[i]->dev.parent = &dev->dev;
+	}
+
+	if (devices_found == 1) {
+		info->cmtd = info->mtd[0];
+	} else if (devices_found > 1) {
+		/*
+		 * We detected multiple devices. Concatenate them together.
+		 */
+		info->cmtd = mtd_concat_create(info->mtd, devices_found,
+					       dev_name(&dev->dev));
+		if (info->cmtd == NULL)
+			err = -ENXIO;
+	}
+	if (err)
+		goto err_out;
+
+	err = parse_mtd_partitions(info->cmtd, part_probe_types,
+	      &info->parts, 0);
+	if (err > 0) {
+		mtd_device_register(info->cmtd, info->parts, err);
+		info->nr_parts = err;
+		return 0;
+	}
+
+	if (flash->nr_parts) {
+		printk(KERN_NOTICE "Using physmap partition information\n");
+		mtd_device_register(info->cmtd, flash->parts,
+		flash->nr_parts);
+		return 0;
+	}
+
+	mtd_device_register(info->cmtd, NULL, 0);
+
+	return 0;
+
+err_out:
+	imx6x_weimnor_remove(dev);
+	return err;
+}
+
+#ifdef CONFIG_PM
+static void imx6x_weimnor_shutdown(struct platform_device *dev)
+{
+	struct imx6x_weimnor_info *info = platform_get_drvdata(dev);
+	int i;
+
+	for (i = 0; i < MAX_RESOURCES && info->mtd[i]; i++)
+		if (info->mtd[i]->suspend && info->mtd[i]->resume)
+			if (info->mtd[i]->suspend(info->mtd[i]) == 0)
+				info->mtd[i]->resume(info->mtd[i]);
+}
+#else
+#define imx6x_weimnor_shutdown NULL
+#endif
+
+static struct platform_driver imx6x_weimnor_driver = {
+	.probe          = imx6x_weimnor_probe,
+	.remove         = __devexit_p(imx6x_weimnor_remove),
+			  .shutdown       = imx6x_weimnor_shutdown,
+	.driver         = {
+		.name   = "imx6x-weimnor",
+		.owner  = THIS_MODULE,
+	},
+};
+
+static int __init imx6x_init(void)
+{
+	int err;
+	err = platform_driver_register(&imx6x_weimnor_driver);
+	return err;
+}
+
+static void __exit imx6x_exit(void)
+{
+	platform_driver_unregister(&imx6x_weimnor_driver);
+}
+
+module_init(imx6x_init);
+module_exit(imx6x_exit);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Oliver Brown <oliver.brown@freescale.com>");
+MODULE_DESCRIPTION("MTD map driver for Freescale iMX");
+