diff options
| -rw-r--r-- | drivers/mtd/maps/Kconfig | 11 | ||||
| -rw-r--r-- | drivers/mtd/maps/Makefile | 1 | ||||
| -rw-r--r-- | drivers/mtd/maps/physmap-bt1-rom.c | 126 | ||||
| -rw-r--r-- | drivers/mtd/maps/physmap-bt1-rom.h | 17 | ||||
| -rw-r--r-- | drivers/mtd/maps/physmap-core.c | 5 |
5 files changed, 160 insertions, 0 deletions
diff --git a/drivers/mtd/maps/Kconfig b/drivers/mtd/maps/Kconfig index fd37553f1b07..6650acbc961e 100644 --- a/drivers/mtd/maps/Kconfig +++ b/drivers/mtd/maps/Kconfig @@ -75,6 +75,17 @@ config MTD_PHYSMAP_OF physically into the CPU's memory. The mapping description here is taken from OF device tree. +config MTD_PHYSMAP_BT1_ROM + bool "Baikal-T1 Boot ROMs OF-based physical memory map handling" + depends on MTD_PHYSMAP_OF + depends on MIPS_BAIKAL_T1 || COMPILE_TEST + select MTD_COMPLEX_MAPPINGS + select MULTIPLEXER + select MUX_MMIO + help + This provides some extra DT physmap parsing for the Baikal-T1 + platforms, some detection and setting up ROMs-specific accessors. + config MTD_PHYSMAP_VERSATILE bool "ARM Versatile OF-based physical memory map handling" depends on MTD_PHYSMAP_OF diff --git a/drivers/mtd/maps/Makefile b/drivers/mtd/maps/Makefile index c0da86a5d26f..79f018cf412f 100644 --- a/drivers/mtd/maps/Makefile +++ b/drivers/mtd/maps/Makefile @@ -18,6 +18,7 @@ obj-$(CONFIG_MTD_CK804XROM) += ck804xrom.o obj-$(CONFIG_MTD_TSUNAMI) += tsunami_flash.o obj-$(CONFIG_MTD_PXA2XX) += pxa2xx-flash.o physmap-objs-y += physmap-core.o +physmap-objs-$(CONFIG_MTD_PHYSMAP_BT1_ROM) += physmap-bt1-rom.o physmap-objs-$(CONFIG_MTD_PHYSMAP_VERSATILE) += physmap-versatile.o physmap-objs-$(CONFIG_MTD_PHYSMAP_GEMINI) += physmap-gemini.o physmap-objs-$(CONFIG_MTD_PHYSMAP_IXP4XX) += physmap-ixp4xx.o diff --git a/drivers/mtd/maps/physmap-bt1-rom.c b/drivers/mtd/maps/physmap-bt1-rom.c new file mode 100644 index 000000000000..27cfe1c63a2e --- /dev/null +++ b/drivers/mtd/maps/physmap-bt1-rom.c @@ -0,0 +1,126 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright (C) 2020 BAIKAL ELECTRONICS, JSC + * + * Authors: + * Serge Semin <Sergey.Semin@baikalelectronics.ru> + * + * Baikal-T1 Physically Mapped Internal ROM driver + */ +#include <linux/bits.h> +#include <linux/device.h> +#include <linux/kernel.h> +#include <linux/mtd/map.h> +#include <linux/mtd/xip.h> +#include <linux/mux/consumer.h> +#include <linux/of.h> +#include <linux/of_device.h> +#include <linux/platform_device.h> +#include <linux/string.h> +#include <linux/types.h> + +#include "physmap-bt1-rom.h" + +/* + * Baikal-T1 SoC ROMs are only accessible by the dword-aligned instructions. + * We have to take this into account when implementing the data read-methods. + * Note there is no need in bothering with endianness, since both Baikal-T1 + * CPU and MMIO are LE. + */ +static map_word __xipram bt1_rom_map_read(struct map_info *map, + unsigned long ofs) +{ + void __iomem *src = map->virt + ofs; + unsigned long shift; + map_word ret; + u32 data; + + /* Read data within offset dword. */ + shift = (unsigned long)src & 0x3; + data = readl_relaxed(src - shift); + if (!shift) { + ret.x[0] = data; + return ret; + } + ret.x[0] = data >> (shift * BITS_PER_BYTE); + + /* Read data from the next dword. */ + shift = 4 - shift; + if (ofs + shift >= map->size) + return ret; + + data = readl_relaxed(src + shift); + ret.x[0] |= data << (shift * BITS_PER_BYTE); + + return ret; +} + +static void __xipram bt1_rom_map_copy_from(struct map_info *map, + void *to, unsigned long from, + ssize_t len) +{ + void __iomem *src = map->virt + from; + ssize_t shift, chunk; + u32 data; + + if (len <= 0 || from >= map->size) + return; + + /* Make sure we don't go over the map limit. */ + len = min_t(ssize_t, map->size - from, len); + + /* + * Since requested data size can be pretty big we have to implement + * the copy procedure as optimal as possible. That's why it's split + * up into the next three stages: unaligned head, aligned body, + * unaligned tail. + */ + shift = (ssize_t)src & 0x3; + if (shift) { + chunk = min_t(ssize_t, 4 - shift, len); + data = readl_relaxed(src - shift); + memcpy(to, &data + shift, chunk); + src += chunk; + to += chunk; + len -= chunk; + } + + while (len >= 4) { + data = readl_relaxed(src); + memcpy(to, &data, 4); + src += 4; + to += 4; + len -= 4; + } + + if (len) { + data = readl_relaxed(src); + memcpy(to, &data, len); + } +} + +int of_flash_probe_bt1_rom(struct platform_device *pdev, + struct device_node *np, + struct map_info *map) +{ + struct device *dev = &pdev->dev; + + /* It's supposed to be read-only MTD. */ + if (!of_device_is_compatible(np, "mtd-rom")) { + dev_info(dev, "No mtd-rom compatible string\n"); + return 0; + } + + /* Multiplatform guard. */ + if (!of_device_is_compatible(np, "baikal,bt1-int-rom")) + return 0; + + /* Sanity check the device parameters retrieved from DTB. */ + if (map->bankwidth != 4) + dev_warn(dev, "Bank width is supposed to be 32 bits wide\n"); + + map->read = bt1_rom_map_read; + map->copy_from = bt1_rom_map_copy_from; + + return 0; +} diff --git a/drivers/mtd/maps/physmap-bt1-rom.h b/drivers/mtd/maps/physmap-bt1-rom.h new file mode 100644 index 000000000000..6782899598a4 --- /dev/null +++ b/drivers/mtd/maps/physmap-bt1-rom.h @@ -0,0 +1,17 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +#include <linux/mtd/map.h> +#include <linux/of.h> + +#ifdef CONFIG_MTD_PHYSMAP_BT1_ROM +int of_flash_probe_bt1_rom(struct platform_device *pdev, + struct device_node *np, + struct map_info *map); +#else +static inline +int of_flash_probe_bt1_rom(struct platform_device *pdev, + struct device_node *np, + struct map_info *map) +{ + return 0; +} +#endif diff --git a/drivers/mtd/maps/physmap-core.c b/drivers/mtd/maps/physmap-core.c index 6372197ad865..001ed5deb622 100644 --- a/drivers/mtd/maps/physmap-core.c +++ b/drivers/mtd/maps/physmap-core.c @@ -41,6 +41,7 @@ #include <linux/pm_runtime.h> #include <linux/gpio/consumer.h> +#include "physmap-bt1-rom.h" #include "physmap-gemini.h" #include "physmap-ixp4xx.h" #include "physmap-versatile.h" @@ -371,6 +372,10 @@ static int physmap_flash_of_init(struct platform_device *dev) info->maps[i].bankwidth = bankwidth; info->maps[i].device_node = dp; + err = of_flash_probe_bt1_rom(dev, dp, &info->maps[i]); + if (err) + return err; + err = of_flash_probe_gemini(dev, dp, &info->maps[i]); if (err) return err; |