diff options
Diffstat (limited to 'drivers/soc/tegra/fuse/fuse-tegra.c')
-rw-r--r-- | drivers/soc/tegra/fuse/fuse-tegra.c | 156 |
1 files changed, 156 insertions, 0 deletions
diff --git a/drivers/soc/tegra/fuse/fuse-tegra.c b/drivers/soc/tegra/fuse/fuse-tegra.c new file mode 100644 index 000000000000..03742edcfe83 --- /dev/null +++ b/drivers/soc/tegra/fuse/fuse-tegra.c @@ -0,0 +1,156 @@ +/* + * Copyright (c) 2013-2014, NVIDIA CORPORATION. All rights reserved. + * + * This program is free software; you can redistribute it and/or modify it + * under the terms and conditions of the GNU General Public License, + * version 2, as published by the Free Software Foundation. + * + * This program is distributed in the hope 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, see <http://www.gnu.org/licenses/>. + * + */ + +#include <linux/device.h> +#include <linux/kobject.h> +#include <linux/kernel.h> +#include <linux/platform_device.h> +#include <linux/of.h> +#include <linux/of_address.h> +#include <linux/io.h> + +#include <soc/tegra/fuse.h> + +#include "fuse.h" + +static u32 (*fuse_readl)(const unsigned int offset); +static int fuse_size; +struct tegra_sku_info tegra_sku_info; + +static const char *tegra_revision_name[TEGRA_REVISION_MAX] = { + [TEGRA_REVISION_UNKNOWN] = "unknown", + [TEGRA_REVISION_A01] = "A01", + [TEGRA_REVISION_A02] = "A02", + [TEGRA_REVISION_A03] = "A03", + [TEGRA_REVISION_A03p] = "A03 prime", + [TEGRA_REVISION_A04] = "A04", +}; + +static u8 fuse_readb(const unsigned int offset) +{ + u32 val; + + val = fuse_readl(round_down(offset, 4)); + val >>= (offset % 4) * 8; + val &= 0xff; + + return val; +} + +static ssize_t fuse_read(struct file *fd, struct kobject *kobj, + struct bin_attribute *attr, char *buf, + loff_t pos, size_t size) +{ + int i; + + if (pos < 0 || pos >= fuse_size) + return 0; + + if (size > fuse_size - pos) + size = fuse_size - pos; + + for (i = 0; i < size; i++) + buf[i] = fuse_readb(pos + i); + + return i; +} + +static struct bin_attribute fuse_bin_attr = { + .attr = { .name = "fuse", .mode = S_IRUGO, }, + .read = fuse_read, +}; + +static const struct of_device_id car_match[] __initconst = { + { .compatible = "nvidia,tegra20-car", }, + { .compatible = "nvidia,tegra30-car", }, + { .compatible = "nvidia,tegra114-car", }, + { .compatible = "nvidia,tegra124-car", }, + {}, +}; + +static void tegra_enable_fuse_clk(void __iomem *base) +{ + u32 reg; + + reg = readl_relaxed(base + 0x48); + reg |= 1 << 28; + writel(reg, base + 0x48); + + /* + * Enable FUSE clock. This needs to be hardcoded because the clock + * subsystem is not active during early boot. + */ + reg = readl(base + 0x14); + reg |= 1 << 7; + writel(reg, base + 0x14); +} + +int tegra_fuse_readl(unsigned long offset, u32 *value) +{ + if (!fuse_readl) + return -EPROBE_DEFER; + + *value = fuse_readl(offset); + + return 0; +} +EXPORT_SYMBOL(tegra_fuse_readl); + +int tegra_fuse_create_sysfs(struct device *dev, int size, + u32 (*readl)(const unsigned int offset)) +{ + if (fuse_size) + return -ENODEV; + + fuse_bin_attr.size = size; + fuse_bin_attr.read = fuse_read; + + fuse_size = size; + fuse_readl = readl; + + return device_create_bin_file(dev, &fuse_bin_attr); +} + +void __init tegra_init_fuse(void) +{ + struct device_node *np; + void __iomem *car_base; + + tegra_init_apbmisc(); + + np = of_find_matching_node(NULL, car_match); + car_base = of_iomap(np, 0); + if (car_base) { + tegra_enable_fuse_clk(car_base); + iounmap(car_base); + } else { + pr_err("Could not enable fuse clk. ioremap tegra car failed.\n"); + return; + } + + if (tegra_get_chip_id() == TEGRA20) + tegra20_init_fuse_early(); + else + tegra30_init_fuse_early(); + + pr_info("Tegra Revision: %s SKU: %d CPU Process: %d Core Process: %d\n", + tegra_revision_name[tegra_sku_info.revision], + tegra_sku_info.sku_id, tegra_sku_info.cpu_process_id, + tegra_sku_info.core_process_id); + pr_debug("Tegra CPU Speedo ID %d, Soc Speedo ID %d\n", + tegra_sku_info.cpu_speedo_id, tegra_sku_info.soc_speedo_id); +} |