| Message ID | 1294257379-417-7-git-send-email-blogic@openwrt.org |
|---|---|
| State | Superseded, archived |
| Headers | show |
Hi John, the EBU doesn't allow unaligned read or write access thus Lantiq added this alignment hack directly in hardware. The addr^=2 is only needed during CFI probe because odd addresses are accessed. A simple solution is inside your patch. The spin_lock_irqsave(&ebu_lock, flags); is actually not needed because the EBU does access arbitration and protection already in hardware. Daniel On 01/05/2011 08:56 PM, John Crispin wrote: > NOR flash is attached to the same EBU (External Bus Unit) as PCI. As described > in the PCI patch, the EBU is a little obscure, resulting in the upper and lower > 16 bit of the data on a 32 bit read are swapped. (essentially we have a addr^=2) > This only happens on the read of data. In order to not have to high an impact > on the read performance from the EBU we store all data on the flash with > addr^=2. This allows us to do generic reads without having to do any swapping. > For the write to now work we need to swizzle the the 0x2 bit of the addr. > However this write swizzle needs to only happen when doing a CMD and not a DATA > write. > > As the MTD layer currently makes no difference between a CMD and DATA read when > using complex maps, the map driver does not know when the swizzle and when not > to swizzle. The next patch in the series adds a hack to the MTD to workaround > this problem. I am sending these 2 patches to the mtd list aswell. There are > several ways to solve this generically in the mtd layer in a much better way. > This will have minor impact on the actual map code provided in this patch. > > Signed-off-by: John Crispin<blogic@openwrt.org> > Signed-off-by: Ralph Hempel<ralph.hempel@lantiq.com> > Cc: David Woodhouse<dwmw2@infradead.org> > Cc: linux-mips@linux-mips.org > Cc: linux-mtd@lists.infradead.org > --- > drivers/mtd/maps/Kconfig | 7 ++ > drivers/mtd/maps/Makefile | 1 + > drivers/mtd/maps/lantiq.c | 169 +++++++++++++++++++++++++++++++++++++++++++++ > 3 files changed, 177 insertions(+), 0 deletions(-) > create mode 100644 drivers/mtd/maps/lantiq.c > > diff --git a/drivers/mtd/maps/Kconfig b/drivers/mtd/maps/Kconfig > index a0dd7bb..ca69a7f 100644 > --- a/drivers/mtd/maps/Kconfig > +++ b/drivers/mtd/maps/Kconfig > @@ -260,6 +260,13 @@ config MTD_BCM963XX > Support for parsing CFE image tag and creating MTD partitions on > Broadcom BCM63xx boards. > > +config MTD_LANTIQ > + bool "Lantiq SoC NOR support" > + depends on LANTIQ&& MTD_PARTITIONS > + help > + Support for NOR flash chips on Lantiq SoC. The Chips are connected > + to the SoCs EBU (External Bus Unit) > + > config MTD_DILNETPC > tristate "CFI Flash device mapped on DIL/Net PC" > depends on X86&& MTD_CONCAT&& MTD_PARTITIONS&& MTD_CFI_INTELEXT&& BROKEN > diff --git a/drivers/mtd/maps/Makefile b/drivers/mtd/maps/Makefile > index c7869c7..bb2ce2f 100644 > --- a/drivers/mtd/maps/Makefile > +++ b/drivers/mtd/maps/Makefile > @@ -59,3 +59,4 @@ obj-$(CONFIG_MTD_RBTX4939) += rbtx4939-flash.o > obj-$(CONFIG_MTD_VMU) += vmu-flash.o > obj-$(CONFIG_MTD_GPIO_ADDR) += gpio-addr-flash.o > obj-$(CONFIG_MTD_BCM963XX) += bcm963xx-flash.o > +obj-$(CONFIG_MTD_LANTIQ) += lantiq.o > diff --git a/drivers/mtd/maps/lantiq.c b/drivers/mtd/maps/lantiq.c > new file mode 100644 > index 0000000..e5a361e > --- /dev/null > +++ b/drivers/mtd/maps/lantiq.c > @@ -0,0 +1,169 @@ > +/* > + * This program is free software; you can redistribute it and/or modify it > + * under the terms of the GNU General Public License version 2 as published > + * by the Free Software Foundation. > + * > + * Copyright (C) 2004 Liu Peng Infineon IFAP DC COM CPE > + * Copyright (C) 2010 John Crispin<blogic@openwrt.org> > + */ > + > +#include<linux/module.h> > +#include<linux/types.h> > +#include<linux/kernel.h> > +#include<linux/io.h> > +#include<linux/init.h> > +#include<linux/mtd/mtd.h> > +#include<linux/mtd/map.h> > +#include<linux/mtd/partitions.h> > +#include<linux/mtd/cfi.h> > +#include<linux/magic.h> > +#include<linux/platform_device.h> > +#include<linux/mtd/physmap.h> > + > +#include<lantiq_soc.h> > +#include<lantiq_platform.h> > + static int ltq_probing = 0; > +static map_word > +ltq_read16(struct map_info *map, unsigned long adr) > +{ > + unsigned long flags; > + map_word temp; > + spin_lock_irqsave(&ebu_lock, flags); if (ltq_probing) adr ^= 2; > + temp.x[0] = *((__u16 *)(map->virt + adr)); > + spin_unlock_irqrestore(&ebu_lock, flags); > + return temp; > +} > + > +static void > +ltq_write16(struct map_info *map, map_word d, unsigned long adr) > +{ > + unsigned long flags; > + spin_lock_irqsave(&ebu_lock, flags); if (ltq_probing) adr ^= 2; > + *((__u16 *)(map->virt + adr)) = d.x[0]; > + spin_unlock_irqrestore(&ebu_lock, flags); > +} > + > +void > +ltq_copy_from(struct map_info *map, void *to, > + unsigned long from, ssize_t len) > +{ > + unsigned char *p; > + unsigned char *to_8; > + unsigned long flags; > + spin_lock_irqsave(&ebu_lock, flags); > + from = (unsigned long)(from + map->virt); > + p = (unsigned char *) from; > + to_8 = (unsigned char *) to; > + while (len--) > + *to_8++ = *p++; > + spin_unlock_irqrestore(&ebu_lock, flags); > +} > + > +void > +ltq_copy_to(struct map_info *map, unsigned long to, > + const void *from, ssize_t len) > +{ > + unsigned char *p = (unsigned char *)from; > + unsigned char *to_8; > + unsigned long flags; > + spin_lock_irqsave(&ebu_lock, flags); > + to += (unsigned long) map->virt; > + to_8 = (unsigned char *)to; > + while (len--) > + *p++ = *to_8++; > + spin_unlock_irqrestore(&ebu_lock, flags); > +} > + > +static const char * const part_probe_types[] = { > + "cmdlinepart", NULL }; > + > +static struct map_info ltq_map = { > + .name = "ltq_nor", > + .bankwidth = 2, > + .read = ltq_read16, > + .write = ltq_write16, > + .copy_from = ltq_copy_from, > + .copy_to = ltq_copy_to, > +}; > + > +static int > +ltq_mtd_probe(struct platform_device *pdev) > +{ > + struct physmap_flash_data *ltq_mtd_data = > + (struct physmap_flash_data *) dev_get_platdata(&pdev->dev); > + struct mtd_info *ltq_mtd = NULL; > + struct mtd_partition *parts = NULL; > + struct resource *res = 0; > + int nr_parts = 0; > + > +#ifdef CONFIG_SOC_TYPE_XWAY > + ltq_w32(ltq_r32(LTQ_EBU_BUSCON0)& ~EBU_WRDIS, LTQ_EBU_BUSCON0); > +#endif > + > + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); > + if (!res) { > + dev_err(&pdev->dev, "failed to get memory resource"); > + return -ENOENT; > + } > + res = request_mem_region(res->start, resource_size(res), > + dev_name(&pdev->dev)); > + if (!res) { > + dev_err(&pdev->dev, "failed to request mem resource"); > + return -EBUSY; > + } > + > + ltq_map.phys = res->start; > + ltq_map.size = resource_size(res); > + ltq_map.virt = ioremap_nocache(ltq_map.phys, ltq_map.size); > + > + if (!ltq_map.virt) { > + dev_err(&pdev->dev, "failed to ioremap!\n"); > + return -EIO; > + } > + ltq_probing = 1; > + ltq_mtd = (struct mtd_info *) do_map_probe("cfi_probe",<q_map); ltq_probing = 0; > + if (!ltq_mtd) { > + iounmap(ltq_map.virt); > + dev_err(&pdev->dev, "probing failed\n"); > + return -ENXIO; > + } > + > + ltq_mtd->owner = THIS_MODULE; > + > + nr_parts = parse_mtd_partitions(ltq_mtd, part_probe_types,&parts, 0); > + if (nr_parts> 0) { > + dev_info(&pdev->dev, > + "using %d partitions from cmdline", nr_parts); > + } else { > + nr_parts = ltq_mtd_data->nr_parts; > + parts = ltq_mtd_data->parts; > + } > + > + add_mtd_partitions(ltq_mtd, parts, nr_parts); > + return 0; > +} > + > +static struct platform_driver ltq_mtd_driver = { > + .probe = ltq_mtd_probe, > + .driver = { > + .name = "ltq_nor", > + .owner = THIS_MODULE, > + }, > +}; > + > +int __init > +init_ltq_mtd(void) > +{ > + int ret = platform_driver_register(<q_mtd_driver); > + if (ret) > + printk(KERN_INFO "ltq_nor: error registering platfom driver"); > + return ret; > +} > + > +module_init(init_ltq_mtd); > + > +MODULE_LICENSE("GPL"); > +MODULE_AUTHOR("John Crispin<blogic@openwrt.org>"); > +MODULE_DESCRIPTION("Lantiq SoC NOR");
On 11/01/11 03:59, Daniel Schwierzeck wrote: > Hi John, > > the EBU doesn't allow unaligned read or write access thus Lantiq added > this alignment hack directly in hardware. The addr^=2 is only needed > during CFI probe because odd addresses are accessed. A simple solution > is inside your patch. > > The spin_lock_irqsave(&ebu_lock, flags); is actually not needed > because the EBU does access arbitration and protection already in > hardware. > > Daniel > Hi Daniel, thx, i will try it out later on and then merge it into v2 of the series. John
diff --git a/drivers/mtd/maps/Kconfig b/drivers/mtd/maps/Kconfig index a0dd7bb..ca69a7f 100644 --- a/drivers/mtd/maps/Kconfig +++ b/drivers/mtd/maps/Kconfig @@ -260,6 +260,13 @@ config MTD_BCM963XX Support for parsing CFE image tag and creating MTD partitions on Broadcom BCM63xx boards. +config MTD_LANTIQ + bool "Lantiq SoC NOR support" + depends on LANTIQ && MTD_PARTITIONS + help + Support for NOR flash chips on Lantiq SoC. The Chips are connected + to the SoCs EBU (External Bus Unit) + config MTD_DILNETPC tristate "CFI Flash device mapped on DIL/Net PC" depends on X86 && MTD_CONCAT && MTD_PARTITIONS && MTD_CFI_INTELEXT && BROKEN diff --git a/drivers/mtd/maps/Makefile b/drivers/mtd/maps/Makefile index c7869c7..bb2ce2f 100644 --- a/drivers/mtd/maps/Makefile +++ b/drivers/mtd/maps/Makefile @@ -59,3 +59,4 @@ obj-$(CONFIG_MTD_RBTX4939) += rbtx4939-flash.o obj-$(CONFIG_MTD_VMU) += vmu-flash.o obj-$(CONFIG_MTD_GPIO_ADDR) += gpio-addr-flash.o obj-$(CONFIG_MTD_BCM963XX) += bcm963xx-flash.o +obj-$(CONFIG_MTD_LANTIQ) += lantiq.o diff --git a/drivers/mtd/maps/lantiq.c b/drivers/mtd/maps/lantiq.c new file mode 100644 index 0000000..e5a361e --- /dev/null +++ b/drivers/mtd/maps/lantiq.c @@ -0,0 +1,169 @@ +/* + * This program is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License version 2 as published + * by the Free Software Foundation. + * + * Copyright (C) 2004 Liu Peng Infineon IFAP DC COM CPE + * Copyright (C) 2010 John Crispin <blogic@openwrt.org> + */ + +#include <linux/module.h> +#include <linux/types.h> +#include <linux/kernel.h> +#include <linux/io.h> +#include <linux/init.h> +#include <linux/mtd/mtd.h> +#include <linux/mtd/map.h> +#include <linux/mtd/partitions.h> +#include <linux/mtd/cfi.h> +#include <linux/magic.h> +#include <linux/platform_device.h> +#include <linux/mtd/physmap.h> + +#include <lantiq_soc.h> +#include <lantiq_platform.h> + +static map_word +ltq_read16(struct map_info *map, unsigned long adr) +{ + unsigned long flags; + map_word temp; + spin_lock_irqsave(&ebu_lock, flags); + adr ^= 2; + temp.x[0] = *((__u16 *)(map->virt + adr)); + spin_unlock_irqrestore(&ebu_lock, flags); + return temp; +} + +static void +ltq_write16(struct map_info *map, map_word d, unsigned long adr) +{ + unsigned long flags; + spin_lock_irqsave(&ebu_lock, flags); + adr ^= 2; + *((__u16 *)(map->virt + adr)) = d.x[0]; + spin_unlock_irqrestore(&ebu_lock, flags); +} + +void +ltq_copy_from(struct map_info *map, void *to, + unsigned long from, ssize_t len) +{ + unsigned char *p; + unsigned char *to_8; + unsigned long flags; + spin_lock_irqsave(&ebu_lock, flags); + from = (unsigned long)(from + map->virt); + p = (unsigned char *) from; + to_8 = (unsigned char *) to; + while (len--) + *to_8++ = *p++; + spin_unlock_irqrestore(&ebu_lock, flags); +} + +void +ltq_copy_to(struct map_info *map, unsigned long to, + const void *from, ssize_t len) +{ + unsigned char *p = (unsigned char *)from; + unsigned char *to_8; + unsigned long flags; + spin_lock_irqsave(&ebu_lock, flags); + to += (unsigned long) map->virt; + to_8 = (unsigned char *)to; + while (len--) + *p++ = *to_8++; + spin_unlock_irqrestore(&ebu_lock, flags); +} + +static const char * const part_probe_types[] = { + "cmdlinepart", NULL }; + +static struct map_info ltq_map = { + .name = "ltq_nor", + .bankwidth = 2, + .read = ltq_read16, + .write = ltq_write16, + .copy_from = ltq_copy_from, + .copy_to = ltq_copy_to, +}; + +static int +ltq_mtd_probe(struct platform_device *pdev) +{ + struct physmap_flash_data *ltq_mtd_data = + (struct physmap_flash_data *) dev_get_platdata(&pdev->dev); + struct mtd_info *ltq_mtd = NULL; + struct mtd_partition *parts = NULL; + struct resource *res = 0; + int nr_parts = 0; + +#ifdef CONFIG_SOC_TYPE_XWAY + ltq_w32(ltq_r32(LTQ_EBU_BUSCON0) & ~EBU_WRDIS, LTQ_EBU_BUSCON0); +#endif + + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + if (!res) { + dev_err(&pdev->dev, "failed to get memory resource"); + return -ENOENT; + } + res = request_mem_region(res->start, resource_size(res), + dev_name(&pdev->dev)); + if (!res) { + dev_err(&pdev->dev, "failed to request mem resource"); + return -EBUSY; + } + + ltq_map.phys = res->start; + ltq_map.size = resource_size(res); + ltq_map.virt = ioremap_nocache(ltq_map.phys, ltq_map.size); + + if (!ltq_map.virt) { + dev_err(&pdev->dev, "failed to ioremap!\n"); + return -EIO; + } + + ltq_mtd = (struct mtd_info *) do_map_probe("cfi_probe", <q_map); + if (!ltq_mtd) { + iounmap(ltq_map.virt); + dev_err(&pdev->dev, "probing failed\n"); + return -ENXIO; + } + + ltq_mtd->owner = THIS_MODULE; + + nr_parts = parse_mtd_partitions(ltq_mtd, part_probe_types, &parts, 0); + if (nr_parts > 0) { + dev_info(&pdev->dev, + "using %d partitions from cmdline", nr_parts); + } else { + nr_parts = ltq_mtd_data->nr_parts; + parts = ltq_mtd_data->parts; + } + + add_mtd_partitions(ltq_mtd, parts, nr_parts); + return 0; +} + +static struct platform_driver ltq_mtd_driver = { + .probe = ltq_mtd_probe, + .driver = { + .name = "ltq_nor", + .owner = THIS_MODULE, + }, +}; + +int __init +init_ltq_mtd(void) +{ + int ret = platform_driver_register(<q_mtd_driver); + if (ret) + printk(KERN_INFO "ltq_nor: error registering platfom driver"); + return ret; +} + +module_init(init_ltq_mtd); + +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("John Crispin <blogic@openwrt.org>"); +MODULE_DESCRIPTION("Lantiq SoC NOR");