linux/drivers/nvmem/vf610-ocotp.c
Thomas Gleixner 97fb5e8d9b treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 284
Based on 1 normalized pattern(s):

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public license version 2 and
  only version 2 as published by the free software foundation this
  program is distributed in the hope that 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

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-only

has been chosen to replace the boilerplate/reference in 294 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Alexios Zavras <alexios.zavras@intel.com>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190529141900.825281744@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-06-05 17:36:37 +02:00

256 lines
6.0 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
/*
* Copyright (C) 2015 Toradex AG.
*
* Author: Sanchayan Maity <sanchayan.maity@toradex.com>
*
* Based on the barebox ocotp driver,
* Copyright (c) 2010 Baruch Siach <baruch@tkos.co.il>
* Orex Computed Radiography
*/
#include <linux/clk.h>
#include <linux/delay.h>
#include <linux/device.h>
#include <linux/io.h>
#include <linux/module.h>
#include <linux/nvmem-provider.h>
#include <linux/of.h>
#include <linux/platform_device.h>
#include <linux/slab.h>
/* OCOTP Register Offsets */
#define OCOTP_CTRL_REG 0x00
#define OCOTP_CTRL_SET 0x04
#define OCOTP_CTRL_CLR 0x08
#define OCOTP_TIMING 0x10
#define OCOTP_DATA 0x20
#define OCOTP_READ_CTRL_REG 0x30
#define OCOTP_READ_FUSE_DATA 0x40
/* OCOTP Register bits and masks */
#define OCOTP_CTRL_WR_UNLOCK 16
#define OCOTP_CTRL_WR_UNLOCK_KEY 0x3E77
#define OCOTP_CTRL_WR_UNLOCK_MASK GENMASK(31, 16)
#define OCOTP_CTRL_ADDR 0
#define OCOTP_CTRL_ADDR_MASK GENMASK(6, 0)
#define OCOTP_CTRL_RELOAD_SHADOWS BIT(10)
#define OCOTP_CTRL_ERR BIT(9)
#define OCOTP_CTRL_BUSY BIT(8)
#define OCOTP_TIMING_STROBE_READ 16
#define OCOTP_TIMING_STROBE_READ_MASK GENMASK(21, 16)
#define OCOTP_TIMING_RELAX 12
#define OCOTP_TIMING_RELAX_MASK GENMASK(15, 12)
#define OCOTP_TIMING_STROBE_PROG 0
#define OCOTP_TIMING_STROBE_PROG_MASK GENMASK(11, 0)
#define OCOTP_READ_CTRL_READ_FUSE 0x1
#define VF610_OCOTP_TIMEOUT 100000
#define BF(value, field) (((value) << field) & field##_MASK)
#define DEF_RELAX 20
static const int base_to_fuse_addr_mappings[][2] = {
{0x400, 0x00},
{0x410, 0x01},
{0x420, 0x02},
{0x450, 0x05},
{0x4F0, 0x0F},
{0x600, 0x20},
{0x610, 0x21},
{0x620, 0x22},
{0x630, 0x23},
{0x640, 0x24},
{0x650, 0x25},
{0x660, 0x26},
{0x670, 0x27},
{0x6F0, 0x2F},
{0x880, 0x38},
{0x890, 0x39},
{0x8A0, 0x3A},
{0x8B0, 0x3B},
{0x8C0, 0x3C},
{0x8D0, 0x3D},
{0x8E0, 0x3E},
{0x8F0, 0x3F},
{0xC80, 0x78},
{0xC90, 0x79},
{0xCA0, 0x7A},
{0xCB0, 0x7B},
{0xCC0, 0x7C},
{0xCD0, 0x7D},
{0xCE0, 0x7E},
{0xCF0, 0x7F},
};
struct vf610_ocotp {
void __iomem *base;
struct clk *clk;
struct device *dev;
struct nvmem_device *nvmem;
int timing;
};
static int vf610_ocotp_wait_busy(void __iomem *base)
{
int timeout = VF610_OCOTP_TIMEOUT;
while ((readl(base) & OCOTP_CTRL_BUSY) && --timeout)
udelay(10);
if (!timeout) {
writel(OCOTP_CTRL_ERR, base + OCOTP_CTRL_CLR);
return -ETIMEDOUT;
}
udelay(10);
return 0;
}
static int vf610_ocotp_calculate_timing(struct vf610_ocotp *ocotp_dev)
{
u32 clk_rate;
u32 relax, strobe_read, strobe_prog;
u32 timing;
clk_rate = clk_get_rate(ocotp_dev->clk);
/* Refer section OTP read/write timing parameters in TRM */
relax = clk_rate / (1000000000 / DEF_RELAX) - 1;
strobe_prog = clk_rate / (1000000000 / 10000) + 2 * (DEF_RELAX + 1) - 1;
strobe_read = clk_rate / (1000000000 / 40) + 2 * (DEF_RELAX + 1) - 1;
timing = BF(relax, OCOTP_TIMING_RELAX);
timing |= BF(strobe_read, OCOTP_TIMING_STROBE_READ);
timing |= BF(strobe_prog, OCOTP_TIMING_STROBE_PROG);
return timing;
}
static int vf610_get_fuse_address(int base_addr_offset)
{
int i;
for (i = 0; i < ARRAY_SIZE(base_to_fuse_addr_mappings); i++) {
if (base_to_fuse_addr_mappings[i][0] == base_addr_offset)
return base_to_fuse_addr_mappings[i][1];
}
return -EINVAL;
}
static int vf610_ocotp_read(void *context, unsigned int offset,
void *val, size_t bytes)
{
struct vf610_ocotp *ocotp = context;
void __iomem *base = ocotp->base;
u32 reg, *buf = val;
int fuse_addr;
int ret;
while (bytes > 0) {
fuse_addr = vf610_get_fuse_address(offset);
if (fuse_addr > 0) {
writel(ocotp->timing, base + OCOTP_TIMING);
ret = vf610_ocotp_wait_busy(base + OCOTP_CTRL_REG);
if (ret)
return ret;
reg = readl(base + OCOTP_CTRL_REG);
reg &= ~OCOTP_CTRL_ADDR_MASK;
reg &= ~OCOTP_CTRL_WR_UNLOCK_MASK;
reg |= BF(fuse_addr, OCOTP_CTRL_ADDR);
writel(reg, base + OCOTP_CTRL_REG);
writel(OCOTP_READ_CTRL_READ_FUSE,
base + OCOTP_READ_CTRL_REG);
ret = vf610_ocotp_wait_busy(base + OCOTP_CTRL_REG);
if (ret)
return ret;
if (readl(base) & OCOTP_CTRL_ERR) {
dev_dbg(ocotp->dev, "Error reading from fuse address %x\n",
fuse_addr);
writel(OCOTP_CTRL_ERR, base + OCOTP_CTRL_CLR);
}
/*
* In case of error, we do not abort and expect to read
* 0xBADABADA as mentioned by the TRM. We just read this
* value and return.
*/
*buf = readl(base + OCOTP_READ_FUSE_DATA);
} else {
*buf = 0;
}
buf++;
bytes -= 4;
offset += 4;
}
return 0;
}
static struct nvmem_config ocotp_config = {
.name = "ocotp",
.stride = 4,
.word_size = 4,
.reg_read = vf610_ocotp_read,
};
static const struct of_device_id ocotp_of_match[] = {
{ .compatible = "fsl,vf610-ocotp", },
{/* sentinel */},
};
MODULE_DEVICE_TABLE(of, ocotp_of_match);
static int vf610_ocotp_probe(struct platform_device *pdev)
{
struct device *dev = &pdev->dev;
struct resource *res;
struct vf610_ocotp *ocotp_dev;
ocotp_dev = devm_kzalloc(dev, sizeof(struct vf610_ocotp), GFP_KERNEL);
if (!ocotp_dev)
return -ENOMEM;
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
ocotp_dev->base = devm_ioremap_resource(dev, res);
if (IS_ERR(ocotp_dev->base))
return PTR_ERR(ocotp_dev->base);
ocotp_dev->clk = devm_clk_get(dev, NULL);
if (IS_ERR(ocotp_dev->clk)) {
dev_err(dev, "failed getting clock, err = %ld\n",
PTR_ERR(ocotp_dev->clk));
return PTR_ERR(ocotp_dev->clk);
}
ocotp_dev->dev = dev;
ocotp_dev->timing = vf610_ocotp_calculate_timing(ocotp_dev);
ocotp_config.size = resource_size(res);
ocotp_config.priv = ocotp_dev;
ocotp_config.dev = dev;
ocotp_dev->nvmem = devm_nvmem_register(dev, &ocotp_config);
return PTR_ERR_OR_ZERO(ocotp_dev->nvmem);
}
static struct platform_driver vf610_ocotp_driver = {
.probe = vf610_ocotp_probe,
.driver = {
.name = "vf610-ocotp",
.of_match_table = ocotp_of_match,
},
};
module_platform_driver(vf610_ocotp_driver);
MODULE_AUTHOR("Sanchayan Maity <sanchayan.maity@toradex.com>");
MODULE_DESCRIPTION("Vybrid OCOTP driver");
MODULE_LICENSE("GPL v2");