| Message ID | 1504036047-38848-1-git-send-email-matthew.weber@rockwellcollins.com |
|---|---|
| State | Changes Requested |
| Headers | show |
| Series | [v2] mtd: map: new driver for NXP IFC | expand |
Dear Matt, > -----Original Message----- > From: linux-mtd [mailto:linux-mtd-bounces@lists.infradead.org] On Behalf Of > Matt Weber > Sent: Wednesday, August 30, 2017 1:17 AM > To: linux-mtd@lists.infradead.org > Cc: Matt Weber <matthew.weber@rockwellcollins.com>; boris.brezillon@free- > electrons.com; Sanjay Tandel <sanjay.tandel@rockwellcollins.com>; > arnd@arndb.de > Subject: [PATCH v2] mtd: map: new driver for NXP IFC > > From: Sanjay Tandel <sanjay.tandel@rockwellcollins.com> > > This patch adds map driver for parallel flash chips interfaced over > a NXP Integrated Flash Controller (IFC). This driver allows either > 8-bit or 16-bit accesses, depending on bank-width, to parallel flash > chips(like Everspin MR0A16A), which are physically mapped to CPU's > memory space. For unaligned accesses, it performs read-modify-write > operations to keep access size same as bank-width. > IFC is configured as per Flash's width per Chip select via boot-loader. Can you please share more details about the driver requirement. What is not working with NXP IFC? --prabhakar
Hi Prabhakar, On Tue, Aug 29, 2017 at 7:37 PM, Prabhakar Kushwaha <prabhakar.kushwaha@nxp.com> wrote: > Dear Matt, > >> -----Original Message----- >> From: linux-mtd [mailto:linux-mtd-bounces@lists.infradead.org] On Behalf Of >> Matt Weber >> Sent: Wednesday, August 30, 2017 1:17 AM >> To: linux-mtd@lists.infradead.org >> Cc: Matt Weber <matthew.weber@rockwellcollins.com>; boris.brezillon@free- >> electrons.com; Sanjay Tandel <sanjay.tandel@rockwellcollins.com>; >> arnd@arndb.de >> Subject: [PATCH v2] mtd: map: new driver for NXP IFC >> >> From: Sanjay Tandel <sanjay.tandel@rockwellcollins.com> >> >> This patch adds map driver for parallel flash chips interfaced over >> a NXP Integrated Flash Controller (IFC). This driver allows either >> 8-bit or 16-bit accesses, depending on bank-width, to parallel flash >> chips(like Everspin MR0A16A), which are physically mapped to CPU's >> memory space. For unaligned accesses, it performs read-modify-write >> operations to keep access size same as bank-width. >> > > > IFC is configured as per Flash's width per Chip select via boot-loader. That's right. We are configuring IFC from boot-loader. > > Can you please share more details about the driver requirement. > What is not working with NXP IFC? 8-bit accesses to 16-bit MRAM (through IFC) , using MTD map driver, seem to corrupt the data. We need this driver to limit all accesses to be bank-width size, For more details, please refer the discussion on following thread: https://patchwork.ozlabs.org/patch/797787/ > > --prabhakar > Regards, Sanjay
Hi, On Tue, 29 Aug 2017 14:47:27 -0500 Matt Weber <matthew.weber@rockwellcollins.com> wrote: > From: Sanjay Tandel <sanjay.tandel@rockwellcollins.com> > > This patch adds map driver for parallel flash chips interfaced over > a NXP Integrated Flash Controller (IFC). This driver allows either > 8-bit or 16-bit accesses, depending on bank-width, to parallel flash > chips(like Everspin MR0A16A), which are physically mapped to CPU's > memory space. For unaligned accesses, it performs read-modify-write > operations to keep access size same as bank-width. > Did you consider re-using the physmap driver [1] and adjust it to your needs like the gemini [2] or versatile [3] drivers do? If you did, what prevents you from using this approach? Regards, Boris [1]http://elixir.free-electrons.com/linux/v4.13-rc7/source/drivers/mtd/maps/physmap_of_core.c [2]http://elixir.free-electrons.com/linux/v4.13-rc7/source/drivers/mtd/maps/physmap_of_gemini.c [3]http://elixir.free-electrons.com/linux/v4.13-rc7/source/drivers/mtd/maps/physmap_of_versatile.c > Signed-off-by: Sanjay Tandel <sanjay.tandel@rockwellcollins.com> > Signed-off-by: Matt Weber <matthew.weber@rockwellcollins.com> > --- > > Changes > v1 -> v2 > - Refactored driver to be custom for the IFC bus controllder > (Suggested by Boris) > - Updated patch name > - Cleaned up description to be specific about issue and behavior > - Version 1 - https://patchwork.ozlabs.org/patch/797787/ > --- > Documentation/devicetree/bindings/mtd/ifc-mram.txt | 34 ++ > drivers/mtd/maps/Kconfig | 13 + > drivers/mtd/maps/Makefile | 1 + > drivers/mtd/maps/ifc_mram.c | 343 +++++++++++++++++++++ > 4 files changed, 391 insertions(+) > create mode 100644 Documentation/devicetree/bindings/mtd/ifc-mram.txt > create mode 100644 drivers/mtd/maps/ifc_mram.c > > diff --git a/Documentation/devicetree/bindings/mtd/ifc-mram.txt b/Documentation/devicetree/bindings/mtd/ifc-mram.txt > new file mode 100644 > index 0000000..c5c3210 > --- /dev/null > +++ b/Documentation/devicetree/bindings/mtd/ifc-mram.txt > @@ -0,0 +1,34 @@ > +Integrated Flash Controller based physically-mapped parallel MRAM, > +NOR flash, MTD-RAM (NVRAM...) > + > + - compatible : should contain the specific model of mtd chip(s) > + used, if known, followed by "ifc-mram". > + - reg : Address range(s) of the mtd chip(s) > + It's possible to (optionally) define multiple "reg" tuples so that > + non-identical chips can be described in one node. > + - bank-width : Width (in bytes) of the bank. Equal to the > + device width times the number of interleaved chips. > + - device-width : (optional) Width of a single mtd chip. If > + omitted, assumed to be equal to 'bank-width'. > + - #address-cells, #size-cells : Must be present if the device has > + sub-nodes representing partitions (see below). In this case > + both #address-cells and #size-cells must be equal to 1. > + - linux,mtd-name: allow to specify the mtd name. > + > +The device tree may optionally contain sub-nodes describing partitions of the > +address space. See partition.txt for more detail. > + > +Example: > + > + mram@1,0 { > + #address-cells = <1>; > + #size-cells = <1>; > + compatible = "everspin,mram", "ifc-mram"; > + reg = <0x1 0x0 0x10000 0x1 0x10000 0x10000>; > + bank-width = <2>; > + > + partition@0 { > + reg = <0 0x00020000>; > + label = "MRAM Data 0"; > + }; > + }; > diff --git a/drivers/mtd/maps/Kconfig b/drivers/mtd/maps/Kconfig > index 542fdf8..95bd44e 100644 > --- a/drivers/mtd/maps/Kconfig > +++ b/drivers/mtd/maps/Kconfig > @@ -419,4 +419,17 @@ config MTD_LATCH_ADDR > > If compiled as a module, it will be called latch-addr-flash. > > +config MTD_IFC_MRAM > + tristate "Map driver for Integrated Flash Controller" > + depends on MTD_COMPLEX_MAPPINGS > + help > + Map driver for chips connected parallely to Integrated Flash > + Controller. This driver allows either 8-bit or 16-bit accesses, > + depending on bank-width, to parallel flash chips, which are > + physically mapped to CPU's memory space. For unaligned accesses, > + it does read-modify-write. > + Example: Everspin MR0A16A. > + > + If compiled as a module, it will be called ifc-mram. > + > endmenu > diff --git a/drivers/mtd/maps/Makefile b/drivers/mtd/maps/Makefile > index 5a09a72..0ab793e 100644 > --- a/drivers/mtd/maps/Makefile > +++ b/drivers/mtd/maps/Makefile > @@ -47,3 +47,4 @@ obj-$(CONFIG_MTD_VMU) += vmu-flash.o > obj-$(CONFIG_MTD_GPIO_ADDR) += gpio-addr-flash.o > obj-$(CONFIG_MTD_LATCH_ADDR) += latch-addr-flash.o > obj-$(CONFIG_MTD_LANTIQ) += lantiq-flash.o > +obj-$(CONFIG_MTD_IFC_MRAM) += ifc_mram.o > diff --git a/drivers/mtd/maps/ifc_mram.c b/drivers/mtd/maps/ifc_mram.c > new file mode 100644 > index 0000000..1341e0a > --- /dev/null > +++ b/drivers/mtd/maps/ifc_mram.c > @@ -0,0 +1,343 @@ > +/* > + * Integrated Flash Controlller Map Driver > + * > + * Copyright 2017 Rockwell Collins > + * > + * Aug 18 2017 Sanjay Tandel <sanjay.tandel@rockwellcollins.com> > + * > + * Based on: > + * Flash mappings described by the OF (or flattened) device tree > + * > + * Copyright (C) 2006 MontaVista Software Inc. > + * Author: Vitaly Wool <vwool@ru.mvista.com> > + * > + * Revised to handle newer style flash binding by: > + * Copyright (C) 2007 David Gibson, IBM Corporation. > + * > + */ > + > +#include <linux/module.h> > +#include <linux/types.h> > +#include <linux/device.h> > +#include <linux/mtd/mtd.h> > +#include <linux/mtd/map.h> > +#include <linux/mtd/partitions.h> > +#include <linux/mtd/concat.h> > +#include <linux/of.h> > +#include <linux/of_address.h> > +#include <linux/of_platform.h> > +#include <linux/slab.h> > + > +static const struct of_device_id ifc_mram_match[] = { > + { > + .compatible = "ifc-mram", > + }, > + {} > +}; > +MODULE_DEVICE_TABLE(of, ifc_mram_match); > +struct ifc_mram_list { > + struct mtd_info *mtd; > + struct map_info map; > + struct resource *res; > +}; > + > +struct ifc_mram { > + struct mtd_info *cmtd; > + int list_size; /* number of elements in ifc_mram_list */ > + struct ifc_mram_list list[0]; > +}; > + > + > +static void ifc_mram_copy_from8(void *to, void __iomem *from, size_t count) > +{ > + u8 *t = to; > + > + while (count > 0) { > + *t = (u8)readb_relaxed(from); > + t++; > + from++; > + count--; > + } > +} > + > +static void ifc_mram_copy_from16(void *to, void __iomem *from, size_t count) > +{ > + u8 *t = to; > + > + if (!(IS_ALIGNED((unsigned long)from, 2))) { > + from = (void __iomem *)ALIGN((unsigned long)from, 2) - 2; > + *(u8 *)t = (u8)((cpu_to_le16(readw_relaxed(from)) & 0xff00) > + >> 8); > + count--; > + t++; > + from += 2; > + } > + while (count >= 2) { > + *(u16 *)t = cpu_to_le16(readw_relaxed(from)); > + count -= 2; > + t += 2; > + from += 2; > + }; > + while (count > 0) { > + *(u8 *)t = (u8)(cpu_to_le16(readw_relaxed(from)) & 0x00ff); > + count--; > + t++; > + from++; > + } > +} > + > +static void ifc_mram_copy_from(struct map_info *map, void *to, > + unsigned long from, ssize_t len) > +{ > + if (map->cached) > + memcpy(to, (char *)map->cached + from, len); > + else if (map_bankwidth_is_1(map)) > + ifc_mram_copy_from8(to, map->virt + from, len); > + else if (map_bankwidth_is_2(map)) > + ifc_mram_copy_from16(to, map->virt + from, len); > + else > + memcpy_fromio(to, map->virt + from, len); > +} > + > +static void ifc_mram_copy_to8(void __iomem *to, const void *from, size_t count) > +{ > + const unsigned char *f = from; > + > + while (count > 0) { > + writeb_relaxed(*f, to); > + count--; > + to++; > + f++; > + } > +} > + > +static void ifc_mram_copy_to16(void __iomem *to, const void *from, size_t count) > +{ > + const unsigned char *f = from; > + u16 d; > + > + if (!(IS_ALIGNED((unsigned long)to, 2))) { > + to = (void __iomem *)ALIGN((unsigned long)to, 2) - 2; > + d = (cpu_to_le16(readw_relaxed(to)) & 0x00ff) > + | ((u16)(*(const u8 *)f) << 8); > + writew_relaxed(le16_to_cpu(d), to); > + count--; > + to += 2; > + f++; > + } > + while (count >= 2) { > + writew_relaxed(le16_to_cpu(*(const u16 *)f), to); > + count -= 2; > + to += 2; > + f += 2; > + }; > + while (count > 0) { > + d = (cpu_to_le16(readw_relaxed(to)) & 0xff00) > + | (u16)(*(const u8 *)f); > + writew_relaxed(le16_to_cpu(d), to); > + count--; > + to++; > + f++; > + } > +} > + > +static void ifc_mram_copy_to(struct map_info *map, unsigned long to, > + const void *from, ssize_t len) > +{ > + if (map_bankwidth_is_1(map)) > + ifc_mram_copy_to8(map->virt + to, from, len); > + else if (map_bankwidth_is_2(map)) > + ifc_mram_copy_to16(map->virt + to, from, len); > + else > + memcpy_toio(map->virt + to, from, len); > +} > +static int ifc_mram_remove(struct platform_device *dev) > +{ > + struct ifc_mram *info; > + int i; > + > + info = dev_get_drvdata(&dev->dev); > + if (!info) > + return 0; > + dev_set_drvdata(&dev->dev, NULL); > + > + if (info->cmtd) { > + mtd_device_unregister(info->cmtd); > + if (info->cmtd != info->list[0].mtd) > + mtd_concat_destroy(info->cmtd); > + } > + > + for (i = 0; i < info->list_size; i++) { > + if (info->list[i].mtd) > + map_destroy(info->list[i].mtd); > + > + if (info->list[i].map.virt) > + iounmap(info->list[i].map.virt); > + > + if (info->list[i].res) { > + release_resource(info->list[i].res); > + kfree(info->list[i].res); > + } > + } > + return 0; > +} > + > +static int ifc_mram_probe(struct platform_device *dev) > +{ > + const struct of_device_id *match; > + struct device_node *dp = dev->dev.of_node; > + struct resource res; > + struct ifc_mram *info; > + const __be32 *width; > + int err; > + int i; > + int count; > + const __be32 *p; > + int reg_tuple_size; > + struct mtd_info **mtd_list = NULL; > + resource_size_t res_size; > + struct mtd_part_parser_data ppdata; > + bool map_indirect; > + const char *mtd_name = NULL; > + > + match = of_match_device(ifc_mram_match, &dev->dev); > + if (!match) { > + pr_info("%s: compatible string not matched\n", __func__); > + return -EINVAL; > + } > + reg_tuple_size = > + (of_n_addr_cells(dp) + of_n_size_cells(dp)) * sizeof(u32); > + > + of_property_read_string(dp, "linux,mtd-name", &mtd_name); > + > + p = of_get_property(dp, "reg", &count); > + if (count % reg_tuple_size != 0) { > + dev_err(&dev->dev, "Malformed reg property on %s\n", > + dev->dev.of_node->full_name); > + err = -EINVAL; > + goto err_flash_remove; > + } > + count /= reg_tuple_size; > + > + err = -ENOMEM; > + info = devm_kzalloc(&dev->dev, > + sizeof(struct ifc_mram) + > + sizeof(struct ifc_mram_list) * count, GFP_KERNEL); > + if (!info) > + goto err_flash_remove; > + > + dev_set_drvdata(&dev->dev, info); > + > + mtd_list = kcalloc(count, sizeof(*mtd_list), GFP_KERNEL); > + if (!mtd_list) > + goto err_flash_remove; > + > + for (i = 0; i < count; i++) { > + err = -ENXIO; > + if (of_address_to_resource(dp, i, &res)) { > + /* > + * Continue with next register tuple if this > + * one is not mappable > + */ > + continue; > + } > + > + dev_dbg(&dev->dev, "ifc_mram device: %pR\n", &res); > + > + err = -EBUSY; > + res_size = resource_size(&res); > + info->list[i].res = request_mem_region(res.start, res_size, > + dev_name(&dev->dev)); > + if (!info->list[i].res) > + goto err_out; > + > + err = -ENXIO; > + width = of_get_property(dp, "bank-width", NULL); > + if (!width) { > + dev_err(&dev->dev, > + "Can't get bank width from device tree\n"); > + goto err_out; > + } > + > + info->list[i].map.name = mtd_name ?: dev_name(&dev->dev); > + info->list[i].map.phys = res.start; > + info->list[i].map.size = res_size; > + info->list[i].map.bankwidth = be32_to_cpup(width); > + info->list[i].map.device_node = dp; > + > + err = -ENOMEM; > + info->list[i].map.virt = ioremap(info->list[i].map.phys, > + info->list[i].map.size); > + if (!info->list[i].map.virt) { > + dev_err(&dev->dev, > + "Failed to ioremap() flash region\n"); > + goto err_out; > + } > + > + simple_map_init(&info->list[i].map); > +#ifdef CONFIG_MTD_COMPLEX_MAPPINGS > + info->list[i].map.copy_from = ifc_mram_copy_from; > + info->list[i].map.copy_to = ifc_mram_copy_to; > +#endif > + > + > + info->list[i].mtd = do_map_probe("map_ram", > + &info->list[i].map); > + mtd_list[i] = info->list[i].mtd; > + > + err = -ENXIO; > + if (!info->list[i].mtd) { > + dev_err(&dev->dev, "do_map_probe() failed\n"); > + goto err_out; > + } else { > + info->list_size++; > + } > + info->list[i].mtd->owner = THIS_MODULE; > + info->list[i].mtd->dev.parent = &dev->dev; > + } > + > + err = 0; > + info->cmtd = NULL; > + if (info->list_size == 1) { > + info->cmtd = info->list[0].mtd; > + } else if (info->list_size > 1) { > + /* > + * We detected multiple devices. Concatenate them together. > + */ > + info->cmtd = mtd_concat_create(mtd_list, info->list_size, > + dev_name(&dev->dev)); > + } > + if (info->cmtd == NULL) > + err = -ENXIO; > + > + if (err) > + goto err_out; > + > + ppdata.of_node = dp; > + mtd_device_parse_register(info->cmtd, NULL, &ppdata, NULL, 0); > + kfree(mtd_list); > + return 0; > + > +err_out: > + kfree(mtd_list); > +err_flash_remove: > + ifc_mram_remove(dev); > + > + return err; > +} > + > + > +static struct platform_driver ifc_mram_driver = { > + .driver = { > + .name = "ifc-mram", > + .of_match_table = ifc_mram_match, > + }, > + .probe = ifc_mram_probe, > + .remove = ifc_mram_remove, > +}; > + > +module_platform_driver(ifc_mram_driver); > + > +MODULE_LICENSE("GPL v2"); > +MODULE_AUTHOR("Sanjay Tandel"); > +MODULE_DESCRIPTION("IFC MRAM Map Driver");
Hi Boris, On Wed, Aug 30, 2017 at 2:34 PM, Boris Brezillon <boris.brezillon@free-electrons.com> wrote: > Hi, > > On Tue, 29 Aug 2017 14:47:27 -0500 > Matt Weber <matthew.weber@rockwellcollins.com> wrote: > >> From: Sanjay Tandel <sanjay.tandel@rockwellcollins.com> >> >> This patch adds map driver for parallel flash chips interfaced over >> a NXP Integrated Flash Controller (IFC). This driver allows either >> 8-bit or 16-bit accesses, depending on bank-width, to parallel flash >> chips(like Everspin MR0A16A), which are physically mapped to CPU's >> memory space. For unaligned accesses, it performs read-modify-write >> operations to keep access size same as bank-width. >> > > Did you consider re-using the physmap driver [1] and adjust it to your > needs like the gemini [2] or versatile [3] drivers do? If you did, what > prevents you from using this approach? That approach would have coupled my driver with physmap driver, which has been modified in newer version of kernel. So patch would not have been backward compatible. I intended to create independent driver without changing any existing driver code. > > Regards, > > Boris > > [1]http://elixir.free-electrons.com/linux/v4.13-rc7/source/drivers/mtd/maps/physmap_of_core.c > [2]http://elixir.free-electrons.com/linux/v4.13-rc7/source/drivers/mtd/maps/physmap_of_gemini.c > [3]http://elixir.free-electrons.com/linux/v4.13-rc7/source/drivers/mtd/maps/physmap_of_versatile.c > Regards, Sanjay >> Signed-off-by: Sanjay Tandel <sanjay.tandel@rockwellcollins.com> >> Signed-off-by: Matt Weber <matthew.weber@rockwellcollins.com> >> --- >> >> Changes >> v1 -> v2 >> - Refactored driver to be custom for the IFC bus controllder >> (Suggested by Boris) >> - Updated patch name >> - Cleaned up description to be specific about issue and behavior >> - Version 1 - https://patchwork.ozlabs.org/patch/797787/ >> --- >> Documentation/devicetree/bindings/mtd/ifc-mram.txt | 34 ++ >> drivers/mtd/maps/Kconfig | 13 + >> drivers/mtd/maps/Makefile | 1 + >> drivers/mtd/maps/ifc_mram.c | 343 +++++++++++++++++++++ >> 4 files changed, 391 insertions(+) >> create mode 100644 Documentation/devicetree/bindings/mtd/ifc-mram.txt >> create mode 100644 drivers/mtd/maps/ifc_mram.c >> >> diff --git a/Documentation/devicetree/bindings/mtd/ifc-mram.txt b/Documentation/devicetree/bindings/mtd/ifc-mram.txt >> new file mode 100644 >> index 0000000..c5c3210 >> --- /dev/null >> +++ b/Documentation/devicetree/bindings/mtd/ifc-mram.txt >> @@ -0,0 +1,34 @@ >> +Integrated Flash Controller based physically-mapped parallel MRAM, >> +NOR flash, MTD-RAM (NVRAM...) >> + >> + - compatible : should contain the specific model of mtd chip(s) >> + used, if known, followed by "ifc-mram". >> + - reg : Address range(s) of the mtd chip(s) >> + It's possible to (optionally) define multiple "reg" tuples so that >> + non-identical chips can be described in one node. >> + - bank-width : Width (in bytes) of the bank. Equal to the >> + device width times the number of interleaved chips. >> + - device-width : (optional) Width of a single mtd chip. If >> + omitted, assumed to be equal to 'bank-width'. >> + - #address-cells, #size-cells : Must be present if the device has >> + sub-nodes representing partitions (see below). In this case >> + both #address-cells and #size-cells must be equal to 1. >> + - linux,mtd-name: allow to specify the mtd name. >> + >> +The device tree may optionally contain sub-nodes describing partitions of the >> +address space. See partition.txt for more detail. >> + >> +Example: >> + >> + mram@1,0 { >> + #address-cells = <1>; >> + #size-cells = <1>; >> + compatible = "everspin,mram", "ifc-mram"; >> + reg = <0x1 0x0 0x10000 0x1 0x10000 0x10000>; >> + bank-width = <2>; >> + >> + partition@0 { >> + reg = <0 0x00020000>; >> + label = "MRAM Data 0"; >> + }; >> + }; >> diff --git a/drivers/mtd/maps/Kconfig b/drivers/mtd/maps/Kconfig >> index 542fdf8..95bd44e 100644 >> --- a/drivers/mtd/maps/Kconfig >> +++ b/drivers/mtd/maps/Kconfig >> @@ -419,4 +419,17 @@ config MTD_LATCH_ADDR >> >> If compiled as a module, it will be called latch-addr-flash. >> >> +config MTD_IFC_MRAM >> + tristate "Map driver for Integrated Flash Controller" >> + depends on MTD_COMPLEX_MAPPINGS >> + help >> + Map driver for chips connected parallely to Integrated Flash >> + Controller. This driver allows either 8-bit or 16-bit accesses, >> + depending on bank-width, to parallel flash chips, which are >> + physically mapped to CPU's memory space. For unaligned accesses, >> + it does read-modify-write. >> + Example: Everspin MR0A16A. >> + >> + If compiled as a module, it will be called ifc-mram. >> + >> endmenu >> diff --git a/drivers/mtd/maps/Makefile b/drivers/mtd/maps/Makefile >> index 5a09a72..0ab793e 100644 >> --- a/drivers/mtd/maps/Makefile >> +++ b/drivers/mtd/maps/Makefile >> @@ -47,3 +47,4 @@ obj-$(CONFIG_MTD_VMU) += vmu-flash.o >> obj-$(CONFIG_MTD_GPIO_ADDR) += gpio-addr-flash.o >> obj-$(CONFIG_MTD_LATCH_ADDR) += latch-addr-flash.o >> obj-$(CONFIG_MTD_LANTIQ) += lantiq-flash.o >> +obj-$(CONFIG_MTD_IFC_MRAM) += ifc_mram.o >> diff --git a/drivers/mtd/maps/ifc_mram.c b/drivers/mtd/maps/ifc_mram.c >> new file mode 100644 >> index 0000000..1341e0a >> --- /dev/null >> +++ b/drivers/mtd/maps/ifc_mram.c >> @@ -0,0 +1,343 @@ >> +/* >> + * Integrated Flash Controlller Map Driver >> + * >> + * Copyright 2017 Rockwell Collins >> + * >> + * Aug 18 2017 Sanjay Tandel <sanjay.tandel@rockwellcollins.com> >> + * >> + * Based on: >> + * Flash mappings described by the OF (or flattened) device tree >> + * >> + * Copyright (C) 2006 MontaVista Software Inc. >> + * Author: Vitaly Wool <vwool@ru.mvista.com> >> + * >> + * Revised to handle newer style flash binding by: >> + * Copyright (C) 2007 David Gibson, IBM Corporation. >> + * >> + */ >> + >> +#include <linux/module.h> >> +#include <linux/types.h> >> +#include <linux/device.h> >> +#include <linux/mtd/mtd.h> >> +#include <linux/mtd/map.h> >> +#include <linux/mtd/partitions.h> >> +#include <linux/mtd/concat.h> >> +#include <linux/of.h> >> +#include <linux/of_address.h> >> +#include <linux/of_platform.h> >> +#include <linux/slab.h> >> + >> +static const struct of_device_id ifc_mram_match[] = { >> + { >> + .compatible = "ifc-mram", >> + }, >> + {} >> +}; >> +MODULE_DEVICE_TABLE(of, ifc_mram_match); >> +struct ifc_mram_list { >> + struct mtd_info *mtd; >> + struct map_info map; >> + struct resource *res; >> +}; >> + >> +struct ifc_mram { >> + struct mtd_info *cmtd; >> + int list_size; /* number of elements in ifc_mram_list */ >> + struct ifc_mram_list list[0]; >> +}; >> + >> + >> +static void ifc_mram_copy_from8(void *to, void __iomem *from, size_t count) >> +{ >> + u8 *t = to; >> + >> + while (count > 0) { >> + *t = (u8)readb_relaxed(from); >> + t++; >> + from++; >> + count--; >> + } >> +} >> + >> +static void ifc_mram_copy_from16(void *to, void __iomem *from, size_t count) >> +{ >> + u8 *t = to; >> + >> + if (!(IS_ALIGNED((unsigned long)from, 2))) { >> + from = (void __iomem *)ALIGN((unsigned long)from, 2) - 2; >> + *(u8 *)t = (u8)((cpu_to_le16(readw_relaxed(from)) & 0xff00) >> + >> 8); >> + count--; >> + t++; >> + from += 2; >> + } >> + while (count >= 2) { >> + *(u16 *)t = cpu_to_le16(readw_relaxed(from)); >> + count -= 2; >> + t += 2; >> + from += 2; >> + }; >> + while (count > 0) { >> + *(u8 *)t = (u8)(cpu_to_le16(readw_relaxed(from)) & 0x00ff); >> + count--; >> + t++; >> + from++; >> + } >> +} >> + >> +static void ifc_mram_copy_from(struct map_info *map, void *to, >> + unsigned long from, ssize_t len) >> +{ >> + if (map->cached) >> + memcpy(to, (char *)map->cached + from, len); >> + else if (map_bankwidth_is_1(map)) >> + ifc_mram_copy_from8(to, map->virt + from, len); >> + else if (map_bankwidth_is_2(map)) >> + ifc_mram_copy_from16(to, map->virt + from, len); >> + else >> + memcpy_fromio(to, map->virt + from, len); >> +} >> + >> +static void ifc_mram_copy_to8(void __iomem *to, const void *from, size_t count) >> +{ >> + const unsigned char *f = from; >> + >> + while (count > 0) { >> + writeb_relaxed(*f, to); >> + count--; >> + to++; >> + f++; >> + } >> +} >> + >> +static void ifc_mram_copy_to16(void __iomem *to, const void *from, size_t count) >> +{ >> + const unsigned char *f = from; >> + u16 d; >> + >> + if (!(IS_ALIGNED((unsigned long)to, 2))) { >> + to = (void __iomem *)ALIGN((unsigned long)to, 2) - 2; >> + d = (cpu_to_le16(readw_relaxed(to)) & 0x00ff) >> + | ((u16)(*(const u8 *)f) << 8); >> + writew_relaxed(le16_to_cpu(d), to); >> + count--; >> + to += 2; >> + f++; >> + } >> + while (count >= 2) { >> + writew_relaxed(le16_to_cpu(*(const u16 *)f), to); >> + count -= 2; >> + to += 2; >> + f += 2; >> + }; >> + while (count > 0) { >> + d = (cpu_to_le16(readw_relaxed(to)) & 0xff00) >> + | (u16)(*(const u8 *)f); >> + writew_relaxed(le16_to_cpu(d), to); >> + count--; >> + to++; >> + f++; >> + } >> +} >> + >> +static void ifc_mram_copy_to(struct map_info *map, unsigned long to, >> + const void *from, ssize_t len) >> +{ >> + if (map_bankwidth_is_1(map)) >> + ifc_mram_copy_to8(map->virt + to, from, len); >> + else if (map_bankwidth_is_2(map)) >> + ifc_mram_copy_to16(map->virt + to, from, len); >> + else >> + memcpy_toio(map->virt + to, from, len); >> +} >> +static int ifc_mram_remove(struct platform_device *dev) >> +{ >> + struct ifc_mram *info; >> + int i; >> + >> + info = dev_get_drvdata(&dev->dev); >> + if (!info) >> + return 0; >> + dev_set_drvdata(&dev->dev, NULL); >> + >> + if (info->cmtd) { >> + mtd_device_unregister(info->cmtd); >> + if (info->cmtd != info->list[0].mtd) >> + mtd_concat_destroy(info->cmtd); >> + } >> + >> + for (i = 0; i < info->list_size; i++) { >> + if (info->list[i].mtd) >> + map_destroy(info->list[i].mtd); >> + >> + if (info->list[i].map.virt) >> + iounmap(info->list[i].map.virt); >> + >> + if (info->list[i].res) { >> + release_resource(info->list[i].res); >> + kfree(info->list[i].res); >> + } >> + } >> + return 0; >> +} >> + >> +static int ifc_mram_probe(struct platform_device *dev) >> +{ >> + const struct of_device_id *match; >> + struct device_node *dp = dev->dev.of_node; >> + struct resource res; >> + struct ifc_mram *info; >> + const __be32 *width; >> + int err; >> + int i; >> + int count; >> + const __be32 *p; >> + int reg_tuple_size; >> + struct mtd_info **mtd_list = NULL; >> + resource_size_t res_size; >> + struct mtd_part_parser_data ppdata; >> + bool map_indirect; >> + const char *mtd_name = NULL; >> + >> + match = of_match_device(ifc_mram_match, &dev->dev); >> + if (!match) { >> + pr_info("%s: compatible string not matched\n", __func__); >> + return -EINVAL; >> + } >> + reg_tuple_size = >> + (of_n_addr_cells(dp) + of_n_size_cells(dp)) * sizeof(u32); >> + >> + of_property_read_string(dp, "linux,mtd-name", &mtd_name); >> + >> + p = of_get_property(dp, "reg", &count); >> + if (count % reg_tuple_size != 0) { >> + dev_err(&dev->dev, "Malformed reg property on %s\n", >> + dev->dev.of_node->full_name); >> + err = -EINVAL; >> + goto err_flash_remove; >> + } >> + count /= reg_tuple_size; >> + >> + err = -ENOMEM; >> + info = devm_kzalloc(&dev->dev, >> + sizeof(struct ifc_mram) + >> + sizeof(struct ifc_mram_list) * count, GFP_KERNEL); >> + if (!info) >> + goto err_flash_remove; >> + >> + dev_set_drvdata(&dev->dev, info); >> + >> + mtd_list = kcalloc(count, sizeof(*mtd_list), GFP_KERNEL); >> + if (!mtd_list) >> + goto err_flash_remove; >> + >> + for (i = 0; i < count; i++) { >> + err = -ENXIO; >> + if (of_address_to_resource(dp, i, &res)) { >> + /* >> + * Continue with next register tuple if this >> + * one is not mappable >> + */ >> + continue; >> + } >> + >> + dev_dbg(&dev->dev, "ifc_mram device: %pR\n", &res); >> + >> + err = -EBUSY; >> + res_size = resource_size(&res); >> + info->list[i].res = request_mem_region(res.start, res_size, >> + dev_name(&dev->dev)); >> + if (!info->list[i].res) >> + goto err_out; >> + >> + err = -ENXIO; >> + width = of_get_property(dp, "bank-width", NULL); >> + if (!width) { >> + dev_err(&dev->dev, >> + "Can't get bank width from device tree\n"); >> + goto err_out; >> + } >> + >> + info->list[i].map.name = mtd_name ?: dev_name(&dev->dev); >> + info->list[i].map.phys = res.start; >> + info->list[i].map.size = res_size; >> + info->list[i].map.bankwidth = be32_to_cpup(width); >> + info->list[i].map.device_node = dp; >> + >> + err = -ENOMEM; >> + info->list[i].map.virt = ioremap(info->list[i].map.phys, >> + info->list[i].map.size); >> + if (!info->list[i].map.virt) { >> + dev_err(&dev->dev, >> + "Failed to ioremap() flash region\n"); >> + goto err_out; >> + } >> + >> + simple_map_init(&info->list[i].map); >> +#ifdef CONFIG_MTD_COMPLEX_MAPPINGS >> + info->list[i].map.copy_from = ifc_mram_copy_from; >> + info->list[i].map.copy_to = ifc_mram_copy_to; >> +#endif >> + >> + >> + info->list[i].mtd = do_map_probe("map_ram", >> + &info->list[i].map); >> + mtd_list[i] = info->list[i].mtd; >> + >> + err = -ENXIO; >> + if (!info->list[i].mtd) { >> + dev_err(&dev->dev, "do_map_probe() failed\n"); >> + goto err_out; >> + } else { >> + info->list_size++; >> + } >> + info->list[i].mtd->owner = THIS_MODULE; >> + info->list[i].mtd->dev.parent = &dev->dev; >> + } >> + >> + err = 0; >> + info->cmtd = NULL; >> + if (info->list_size == 1) { >> + info->cmtd = info->list[0].mtd; >> + } else if (info->list_size > 1) { >> + /* >> + * We detected multiple devices. Concatenate them together. >> + */ >> + info->cmtd = mtd_concat_create(mtd_list, info->list_size, >> + dev_name(&dev->dev)); >> + } >> + if (info->cmtd == NULL) >> + err = -ENXIO; >> + >> + if (err) >> + goto err_out; >> + >> + ppdata.of_node = dp; >> + mtd_device_parse_register(info->cmtd, NULL, &ppdata, NULL, 0); >> + kfree(mtd_list); >> + return 0; >> + >> +err_out: >> + kfree(mtd_list); >> +err_flash_remove: >> + ifc_mram_remove(dev); >> + >> + return err; >> +} >> + >> + >> +static struct platform_driver ifc_mram_driver = { >> + .driver = { >> + .name = "ifc-mram", >> + .of_match_table = ifc_mram_match, >> + }, >> + .probe = ifc_mram_probe, >> + .remove = ifc_mram_remove, >> +}; >> + >> +module_platform_driver(ifc_mram_driver); >> + >> +MODULE_LICENSE("GPL v2"); >> +MODULE_AUTHOR("Sanjay Tandel"); >> +MODULE_DESCRIPTION("IFC MRAM Map Driver"); >
On Wed, 30 Aug 2017 19:03:48 -0500 Sanjay Tandel <sanjay.tandel@rockwellcollins.com> wrote: > Hi Boris, > > On Wed, Aug 30, 2017 at 2:34 PM, Boris Brezillon > <boris.brezillon@free-electrons.com> wrote: > > Hi, > > > > On Tue, 29 Aug 2017 14:47:27 -0500 > > Matt Weber <matthew.weber@rockwellcollins.com> wrote: > > > >> From: Sanjay Tandel <sanjay.tandel@rockwellcollins.com> > >> > >> This patch adds map driver for parallel flash chips interfaced over > >> a NXP Integrated Flash Controller (IFC). This driver allows either > >> 8-bit or 16-bit accesses, depending on bank-width, to parallel flash > >> chips(like Everspin MR0A16A), which are physically mapped to CPU's > >> memory space. For unaligned accesses, it performs read-modify-write > >> operations to keep access size same as bank-width. > >> > > > > Did you consider re-using the physmap driver [1] and adjust it to your > > needs like the gemini [2] or versatile [3] drivers do? If you did, what > > prevents you from using this approach? > > That approach would have coupled my driver with physmap driver, which has been > modified in newer version of kernel. So patch would not have been backward > compatible. Backward compatible? I guess you meant backport-able, and I don't think this is a good argument. We want Fixes to be backportable if they impact several releases, not new drivers. If you want to backport your driver to previous versions of Linux you can do it but it will never be included in the official stable releases. > > I intended to create independent driver without changing any existing > driver code. Please look at the versatile and gemini driver, there's almost nothing to change in the physmap_of_core.c file, and you'll have your own source file (+ Kconfig option) where you can tweak the map hooks as you wish. Regards, Boris
On Thu, Aug 31, 2017 at 1:32 AM, Boris Brezillon <boris.brezillon@free-electrons.com> wrote: > On Wed, 30 Aug 2017 19:03:48 -0500 > Sanjay Tandel <sanjay.tandel@rockwellcollins.com> wrote: > >> Hi Boris, >> >> On Wed, Aug 30, 2017 at 2:34 PM, Boris Brezillon >> <boris.brezillon@free-electrons.com> wrote: >> > Hi, >> > >> > On Tue, 29 Aug 2017 14:47:27 -0500 >> > Matt Weber <matthew.weber@rockwellcollins.com> wrote: >> > >> >> From: Sanjay Tandel <sanjay.tandel@rockwellcollins.com> >> >> >> >> This patch adds map driver for parallel flash chips interfaced over >> >> a NXP Integrated Flash Controller (IFC). This driver allows either >> >> 8-bit or 16-bit accesses, depending on bank-width, to parallel flash >> >> chips(like Everspin MR0A16A), which are physically mapped to CPU's >> >> memory space. For unaligned accesses, it performs read-modify-write >> >> operations to keep access size same as bank-width. >> >> >> > >> > Did you consider re-using the physmap driver [1] and adjust it to your >> > needs like the gemini [2] or versatile [3] drivers do? If you did, what >> > prevents you from using this approach? >> >> That approach would have coupled my driver with physmap driver, which has been >> modified in newer version of kernel. So patch would not have been backward >> compatible. > > Backward compatible? I guess you meant backport-able, and I don't think > this is a good argument. We want Fixes to be backportable if they > impact several releases, not new drivers. If you want to backport your > driver to previous versions of Linux you can do it but it will never be > included in the official stable releases. We would leave the patch this way. It's okay if it is not included in official release. > >> >> I intended to create independent driver without changing any existing >> driver code. > > Please look at the versatile and gemini driver, there's almost nothing > to change in the physmap_of_core.c file, and you'll have your own > source file (+ Kconfig option) where you can tweak the map hooks as you > wish. I saw those drivers and they look pretty much simple to hook with physmap by just calling the probe function from physmap. Thanks for your inputs!!! > > Regards, > > Boris Regards, Sanjay
diff --git a/Documentation/devicetree/bindings/mtd/ifc-mram.txt b/Documentation/devicetree/bindings/mtd/ifc-mram.txt new file mode 100644 index 0000000..c5c3210 --- /dev/null +++ b/Documentation/devicetree/bindings/mtd/ifc-mram.txt @@ -0,0 +1,34 @@ +Integrated Flash Controller based physically-mapped parallel MRAM, +NOR flash, MTD-RAM (NVRAM...) + + - compatible : should contain the specific model of mtd chip(s) + used, if known, followed by "ifc-mram". + - reg : Address range(s) of the mtd chip(s) + It's possible to (optionally) define multiple "reg" tuples so that + non-identical chips can be described in one node. + - bank-width : Width (in bytes) of the bank. Equal to the + device width times the number of interleaved chips. + - device-width : (optional) Width of a single mtd chip. If + omitted, assumed to be equal to 'bank-width'. + - #address-cells, #size-cells : Must be present if the device has + sub-nodes representing partitions (see below). In this case + both #address-cells and #size-cells must be equal to 1. + - linux,mtd-name: allow to specify the mtd name. + +The device tree may optionally contain sub-nodes describing partitions of the +address space. See partition.txt for more detail. + +Example: + + mram@1,0 { + #address-cells = <1>; + #size-cells = <1>; + compatible = "everspin,mram", "ifc-mram"; + reg = <0x1 0x0 0x10000 0x1 0x10000 0x10000>; + bank-width = <2>; + + partition@0 { + reg = <0 0x00020000>; + label = "MRAM Data 0"; + }; + }; diff --git a/drivers/mtd/maps/Kconfig b/drivers/mtd/maps/Kconfig index 542fdf8..95bd44e 100644 --- a/drivers/mtd/maps/Kconfig +++ b/drivers/mtd/maps/Kconfig @@ -419,4 +419,17 @@ config MTD_LATCH_ADDR If compiled as a module, it will be called latch-addr-flash. +config MTD_IFC_MRAM + tristate "Map driver for Integrated Flash Controller" + depends on MTD_COMPLEX_MAPPINGS + help + Map driver for chips connected parallely to Integrated Flash + Controller. This driver allows either 8-bit or 16-bit accesses, + depending on bank-width, to parallel flash chips, which are + physically mapped to CPU's memory space. For unaligned accesses, + it does read-modify-write. + Example: Everspin MR0A16A. + + If compiled as a module, it will be called ifc-mram. + endmenu diff --git a/drivers/mtd/maps/Makefile b/drivers/mtd/maps/Makefile index 5a09a72..0ab793e 100644 --- a/drivers/mtd/maps/Makefile +++ b/drivers/mtd/maps/Makefile @@ -47,3 +47,4 @@ obj-$(CONFIG_MTD_VMU) += vmu-flash.o obj-$(CONFIG_MTD_GPIO_ADDR) += gpio-addr-flash.o obj-$(CONFIG_MTD_LATCH_ADDR) += latch-addr-flash.o obj-$(CONFIG_MTD_LANTIQ) += lantiq-flash.o +obj-$(CONFIG_MTD_IFC_MRAM) += ifc_mram.o diff --git a/drivers/mtd/maps/ifc_mram.c b/drivers/mtd/maps/ifc_mram.c new file mode 100644 index 0000000..1341e0a --- /dev/null +++ b/drivers/mtd/maps/ifc_mram.c @@ -0,0 +1,343 @@ +/* + * Integrated Flash Controlller Map Driver + * + * Copyright 2017 Rockwell Collins + * + * Aug 18 2017 Sanjay Tandel <sanjay.tandel@rockwellcollins.com> + * + * Based on: + * Flash mappings described by the OF (or flattened) device tree + * + * Copyright (C) 2006 MontaVista Software Inc. + * Author: Vitaly Wool <vwool@ru.mvista.com> + * + * Revised to handle newer style flash binding by: + * Copyright (C) 2007 David Gibson, IBM Corporation. + * + */ + +#include <linux/module.h> +#include <linux/types.h> +#include <linux/device.h> +#include <linux/mtd/mtd.h> +#include <linux/mtd/map.h> +#include <linux/mtd/partitions.h> +#include <linux/mtd/concat.h> +#include <linux/of.h> +#include <linux/of_address.h> +#include <linux/of_platform.h> +#include <linux/slab.h> + +static const struct of_device_id ifc_mram_match[] = { + { + .compatible = "ifc-mram", + }, + {} +}; +MODULE_DEVICE_TABLE(of, ifc_mram_match); +struct ifc_mram_list { + struct mtd_info *mtd; + struct map_info map; + struct resource *res; +}; + +struct ifc_mram { + struct mtd_info *cmtd; + int list_size; /* number of elements in ifc_mram_list */ + struct ifc_mram_list list[0]; +}; + + +static void ifc_mram_copy_from8(void *to, void __iomem *from, size_t count) +{ + u8 *t = to; + + while (count > 0) { + *t = (u8)readb_relaxed(from); + t++; + from++; + count--; + } +} + +static void ifc_mram_copy_from16(void *to, void __iomem *from, size_t count) +{ + u8 *t = to; + + if (!(IS_ALIGNED((unsigned long)from, 2))) { + from = (void __iomem *)ALIGN((unsigned long)from, 2) - 2; + *(u8 *)t = (u8)((cpu_to_le16(readw_relaxed(from)) & 0xff00) + >> 8); + count--; + t++; + from += 2; + } + while (count >= 2) { + *(u16 *)t = cpu_to_le16(readw_relaxed(from)); + count -= 2; + t += 2; + from += 2; + }; + while (count > 0) { + *(u8 *)t = (u8)(cpu_to_le16(readw_relaxed(from)) & 0x00ff); + count--; + t++; + from++; + } +} + +static void ifc_mram_copy_from(struct map_info *map, void *to, + unsigned long from, ssize_t len) +{ + if (map->cached) + memcpy(to, (char *)map->cached + from, len); + else if (map_bankwidth_is_1(map)) + ifc_mram_copy_from8(to, map->virt + from, len); + else if (map_bankwidth_is_2(map)) + ifc_mram_copy_from16(to, map->virt + from, len); + else + memcpy_fromio(to, map->virt + from, len); +} + +static void ifc_mram_copy_to8(void __iomem *to, const void *from, size_t count) +{ + const unsigned char *f = from; + + while (count > 0) { + writeb_relaxed(*f, to); + count--; + to++; + f++; + } +} + +static void ifc_mram_copy_to16(void __iomem *to, const void *from, size_t count) +{ + const unsigned char *f = from; + u16 d; + + if (!(IS_ALIGNED((unsigned long)to, 2))) { + to = (void __iomem *)ALIGN((unsigned long)to, 2) - 2; + d = (cpu_to_le16(readw_relaxed(to)) & 0x00ff) + | ((u16)(*(const u8 *)f) << 8); + writew_relaxed(le16_to_cpu(d), to); + count--; + to += 2; + f++; + } + while (count >= 2) { + writew_relaxed(le16_to_cpu(*(const u16 *)f), to); + count -= 2; + to += 2; + f += 2; + }; + while (count > 0) { + d = (cpu_to_le16(readw_relaxed(to)) & 0xff00) + | (u16)(*(const u8 *)f); + writew_relaxed(le16_to_cpu(d), to); + count--; + to++; + f++; + } +} + +static void ifc_mram_copy_to(struct map_info *map, unsigned long to, + const void *from, ssize_t len) +{ + if (map_bankwidth_is_1(map)) + ifc_mram_copy_to8(map->virt + to, from, len); + else if (map_bankwidth_is_2(map)) + ifc_mram_copy_to16(map->virt + to, from, len); + else + memcpy_toio(map->virt + to, from, len); +} +static int ifc_mram_remove(struct platform_device *dev) +{ + struct ifc_mram *info; + int i; + + info = dev_get_drvdata(&dev->dev); + if (!info) + return 0; + dev_set_drvdata(&dev->dev, NULL); + + if (info->cmtd) { + mtd_device_unregister(info->cmtd); + if (info->cmtd != info->list[0].mtd) + mtd_concat_destroy(info->cmtd); + } + + for (i = 0; i < info->list_size; i++) { + if (info->list[i].mtd) + map_destroy(info->list[i].mtd); + + if (info->list[i].map.virt) + iounmap(info->list[i].map.virt); + + if (info->list[i].res) { + release_resource(info->list[i].res); + kfree(info->list[i].res); + } + } + return 0; +} + +static int ifc_mram_probe(struct platform_device *dev) +{ + const struct of_device_id *match; + struct device_node *dp = dev->dev.of_node; + struct resource res; + struct ifc_mram *info; + const __be32 *width; + int err; + int i; + int count; + const __be32 *p; + int reg_tuple_size; + struct mtd_info **mtd_list = NULL; + resource_size_t res_size; + struct mtd_part_parser_data ppdata; + bool map_indirect; + const char *mtd_name = NULL; + + match = of_match_device(ifc_mram_match, &dev->dev); + if (!match) { + pr_info("%s: compatible string not matched\n", __func__); + return -EINVAL; + } + reg_tuple_size = + (of_n_addr_cells(dp) + of_n_size_cells(dp)) * sizeof(u32); + + of_property_read_string(dp, "linux,mtd-name", &mtd_name); + + p = of_get_property(dp, "reg", &count); + if (count % reg_tuple_size != 0) { + dev_err(&dev->dev, "Malformed reg property on %s\n", + dev->dev.of_node->full_name); + err = -EINVAL; + goto err_flash_remove; + } + count /= reg_tuple_size; + + err = -ENOMEM; + info = devm_kzalloc(&dev->dev, + sizeof(struct ifc_mram) + + sizeof(struct ifc_mram_list) * count, GFP_KERNEL); + if (!info) + goto err_flash_remove; + + dev_set_drvdata(&dev->dev, info); + + mtd_list = kcalloc(count, sizeof(*mtd_list), GFP_KERNEL); + if (!mtd_list) + goto err_flash_remove; + + for (i = 0; i < count; i++) { + err = -ENXIO; + if (of_address_to_resource(dp, i, &res)) { + /* + * Continue with next register tuple if this + * one is not mappable + */ + continue; + } + + dev_dbg(&dev->dev, "ifc_mram device: %pR\n", &res); + + err = -EBUSY; + res_size = resource_size(&res); + info->list[i].res = request_mem_region(res.start, res_size, + dev_name(&dev->dev)); + if (!info->list[i].res) + goto err_out; + + err = -ENXIO; + width = of_get_property(dp, "bank-width", NULL); + if (!width) { + dev_err(&dev->dev, + "Can't get bank width from device tree\n"); + goto err_out; + } + + info->list[i].map.name = mtd_name ?: dev_name(&dev->dev); + info->list[i].map.phys = res.start; + info->list[i].map.size = res_size; + info->list[i].map.bankwidth = be32_to_cpup(width); + info->list[i].map.device_node = dp; + + err = -ENOMEM; + info->list[i].map.virt = ioremap(info->list[i].map.phys, + info->list[i].map.size); + if (!info->list[i].map.virt) { + dev_err(&dev->dev, + "Failed to ioremap() flash region\n"); + goto err_out; + } + + simple_map_init(&info->list[i].map); +#ifdef CONFIG_MTD_COMPLEX_MAPPINGS + info->list[i].map.copy_from = ifc_mram_copy_from; + info->list[i].map.copy_to = ifc_mram_copy_to; +#endif + + + info->list[i].mtd = do_map_probe("map_ram", + &info->list[i].map); + mtd_list[i] = info->list[i].mtd; + + err = -ENXIO; + if (!info->list[i].mtd) { + dev_err(&dev->dev, "do_map_probe() failed\n"); + goto err_out; + } else { + info->list_size++; + } + info->list[i].mtd->owner = THIS_MODULE; + info->list[i].mtd->dev.parent = &dev->dev; + } + + err = 0; + info->cmtd = NULL; + if (info->list_size == 1) { + info->cmtd = info->list[0].mtd; + } else if (info->list_size > 1) { + /* + * We detected multiple devices. Concatenate them together. + */ + info->cmtd = mtd_concat_create(mtd_list, info->list_size, + dev_name(&dev->dev)); + } + if (info->cmtd == NULL) + err = -ENXIO; + + if (err) + goto err_out; + + ppdata.of_node = dp; + mtd_device_parse_register(info->cmtd, NULL, &ppdata, NULL, 0); + kfree(mtd_list); + return 0; + +err_out: + kfree(mtd_list); +err_flash_remove: + ifc_mram_remove(dev); + + return err; +} + + +static struct platform_driver ifc_mram_driver = { + .driver = { + .name = "ifc-mram", + .of_match_table = ifc_mram_match, + }, + .probe = ifc_mram_probe, + .remove = ifc_mram_remove, +}; + +module_platform_driver(ifc_mram_driver); + +MODULE_LICENSE("GPL v2"); +MODULE_AUTHOR("Sanjay Tandel"); +MODULE_DESCRIPTION("IFC MRAM Map Driver");