diff options
Diffstat (limited to 'target/linux/bcm53xx/files')
| -rw-r--r-- | target/linux/bcm53xx/files/drivers/misc/bcm47xx-nvram.c | 215 |
1 files changed, 215 insertions, 0 deletions
diff --git a/target/linux/bcm53xx/files/drivers/misc/bcm47xx-nvram.c b/target/linux/bcm53xx/files/drivers/misc/bcm47xx-nvram.c new file mode 100644 index 0000000..6ea715c --- /dev/null +++ b/target/linux/bcm53xx/files/drivers/misc/bcm47xx-nvram.c @@ -0,0 +1,215 @@ +/* + * BCM947xx nvram variable access + * + * Copyright (C) 2005 Broadcom Corporation + * Copyright (C) 2006 Felix Fietkau <nbd@openwrt.org> + * Copyright (C) 2010-2014 Hauke Mehrtens <hauke@hauke-m.de> + * + * 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. + */ + +#include <linux/types.h> +#include <linux/module.h> +#include <linux/kernel.h> +#include <linux/string.h> +#include <linux/of_address.h> +#include <linux/device.h> +#include <linux/platform_device.h> +#include <linux/io.h> +#include <linux/bcm47xx_nvram.h> + +struct bcm47xx_nvram { + size_t nvram_len; + char *nvram_buf; +}; + +static const u32 nvram_sizes[] = {0x8000, 0xF000, 0x10000}; + +static u32 find_nvram_size(void __iomem *end) +{ + struct nvram_header __iomem *header; + int i; + + for (i = 0; i < ARRAY_SIZE(nvram_sizes); i++) { + header = (struct nvram_header __iomem *)(end - nvram_sizes[i]); + if (__raw_readl(&header->magic) == NVRAM_HEADER) + return nvram_sizes[i]; + } + + return 0; +} + +/* Probe for NVRAM header */ +static int nvram_find_and_copy(struct device *dev, void __iomem *base, + size_t len, char **nvram_buf, + size_t *nvram_len) +{ + struct nvram_header __iomem *header; + int i; + u32 off; + u32 *dst; + __le32 __iomem *src; + u32 size; + + /* TODO: when nvram is on nand flash check for bad blocks first. */ + off = FLASH_MIN; + while (off <= len) { + /* Windowed flash access */ + size = find_nvram_size(base + off); + if (size) { + header = (struct nvram_header __iomem *) + (base + off - size); + goto found; + } + off += 0x10000; + } + + /* Try embedded NVRAM at 4 KB and 1 KB as last resorts */ + header = (struct nvram_header __iomem *)(base + 4096); + if (__raw_readl(&header->magic) == NVRAM_HEADER) { + size = NVRAM_SPACE; + goto found; + } + + header = (struct nvram_header __iomem *)(base + 1024); + if (__raw_readl(&header->magic) == NVRAM_HEADER) { + size = NVRAM_SPACE; + goto found; + } + + *nvram_buf = NULL; + *nvram_len = 0; + pr_err("no nvram found\n"); + return -ENXIO; + +found: + if (readl(&header->len) > size) + pr_err("The nvram size accoridng to the header seems to be bigger than the partition on flash\n"); + *nvram_len = min_t(u32, readl(&header->len), size); + + *nvram_buf = devm_kzalloc(dev, *nvram_len, GFP_KERNEL); + if (!*nvram_buf) + return -ENOMEM; + + src = (__le32 __iomem *) header; + dst = (u32 *) *nvram_buf; + for (i = 0; i < sizeof(struct nvram_header); i += 4) + *dst++ = __raw_readl(src++); + for (; i < *nvram_len; i += 4) + *dst++ = readl(src++); + + return 0; +} + +int bcm47xx_nvram_getenv(const struct device *dev, const char *name, char *val, + size_t val_len) +{ + char *var, *value, *end, *eq; + struct bcm47xx_nvram *nvram; + + if (!dev) + return -ENODEV; + + nvram = dev_get_drvdata(dev); + + if (!name || !nvram || !nvram->nvram_len) + return -EINVAL; + + /* Look for name=value and return value */ + var = nvram->nvram_buf + sizeof(struct nvram_header); + end = nvram->nvram_buf + nvram->nvram_len - 2; + end[0] = end[1] = '\0'; + for (; *var; var = value + strlen(value) + 1) { + eq = strchr(var, '='); + if (!eq) + break; + value = eq + 1; + if ((eq - var) == strlen(name) && + strncmp(var, name, (eq - var)) == 0) { + return snprintf(val, val_len, "%s", value); + } + } + return -ENOENT; +} +EXPORT_SYMBOL(bcm47xx_nvram_getenv); + +int bcm47xx_nvram_gpio_pin(const struct device *dev, const char *name) +{ + int i, err; + char nvram_var[10]; + char buf[30]; + + if (!dev) + return -ENODEV; + + for (i = 0; i < 32; i++) { + err = snprintf(nvram_var, sizeof(nvram_var), "gpio%i", i); + if (err <= 0) + continue; + err = bcm47xx_nvram_getenv(dev, nvram_var, buf, sizeof(buf)); + if (err <= 0) + continue; + if (!strcmp(name, buf)) + return i; + } + return -ENOENT; +} +EXPORT_SYMBOL(bcm47xx_nvram_gpio_pin); + +static int bcm47xx_nvram_probe(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + struct device_node *np = dev->of_node; + struct bcm47xx_nvram *nvram; + int err; + struct resource flash_mem; + void __iomem *mmio; + + /* Alloc */ + nvram = devm_kzalloc(dev, sizeof(*nvram), GFP_KERNEL); + if (!nvram) + return -ENOMEM; + + err = of_address_to_resource(np, 0, &flash_mem); + if (err) + return err; + + mmio = ioremap_nocache(flash_mem.start, resource_size(&flash_mem)); + if (!mmio) + return -ENOMEM; + + err = nvram_find_and_copy(dev, mmio, resource_size(&flash_mem), + &nvram->nvram_buf, &nvram->nvram_len); + if (err) + goto err_unmap_mmio; + + platform_set_drvdata(pdev, nvram); + +err_unmap_mmio: + iounmap(mmio); + return err; +} + +static const struct of_device_id bcm47xx_nvram_of_match_table[] = { + { .compatible = "brcm,bcm47xx-nvram", }, + {}, +}; +MODULE_DEVICE_TABLE(of, mvebu_pcie_of_match_table); + +static struct platform_driver bcm47xx_nvram_driver = { + .driver = { + .owner = THIS_MODULE, + .name = "bcm47xx-nvram", + .of_match_table = bcm47xx_nvram_of_match_table, + /* driver unloading/unbinding currently not supported */ + .suppress_bind_attrs = true, + }, + .probe = bcm47xx_nvram_probe, +}; +module_platform_driver(bcm47xx_nvram_driver); + +MODULE_AUTHOR("Hauke Mehrtens <hauke@hauke-m.de>"); +MODULE_LICENSE("GPLv2"); |