#include <linux/clk.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>
#include <linux/delay.h>
#define IMX_OCOTP_OFFSET_B0W0 0x400 /* Offset from base address of the
* OTP Bank0 Word0
*/
#define IMX_OCOTP_OFFSET_PER_WORD 0x10 /* Offset between the start addr
* of two consecutive OTP words.
*/
#define IMX_OCOTP_ADDR_CTRL 0x0000
#define IMX_OCOTP_ADDR_CTRL_SET 0x0004
#define IMX_OCOTP_ADDR_CTRL_CLR 0x0008
#define IMX_OCOTP_ADDR_TIMING 0x0010
#define IMX_OCOTP_ADDR_DATA0 0x0020
#define IMX_OCOTP_ADDR_DATA1 0x0030
#define IMX_OCOTP_ADDR_DATA2 0x0040
#define IMX_OCOTP_ADDR_DATA3 0x0050
#define IMX_OCOTP_BM_CTRL_ADDR 0x000000FF
#define IMX_OCOTP_BM_CTRL_BUSY 0x00000100
#define IMX_OCOTP_BM_CTRL_ERROR 0x00000200
#define IMX_OCOTP_BM_CTRL_REL_SHADOWS 0x00000400
#define IMX_OCOTP_BM_CTRL_ADDR_8MP 0x000001FF
#define IMX_OCOTP_BM_CTRL_BUSY_8MP 0x00000200
#define IMX_OCOTP_BM_CTRL_ERROR_8MP 0x00000400
#define IMX_OCOTP_BM_CTRL_REL_SHADOWS_8MP 0x00000800
#define IMX_OCOTP_BM_CTRL_DEFAULT \
{ \
.bm_addr = IMX_OCOTP_BM_CTRL_ADDR, \
.bm_busy = IMX_OCOTP_BM_CTRL_BUSY, \
.bm_error = IMX_OCOTP_BM_CTRL_ERROR, \
.bm_rel_shadows = IMX_OCOTP_BM_CTRL_REL_SHADOWS,\
}
#define IMX_OCOTP_BM_CTRL_8MP \
{ \
.bm_addr = IMX_OCOTP_BM_CTRL_ADDR_8MP, \
.bm_busy = IMX_OCOTP_BM_CTRL_BUSY_8MP, \
.bm_error = IMX_OCOTP_BM_CTRL_ERROR_8MP, \
.bm_rel_shadows = IMX_OCOTP_BM_CTRL_REL_SHADOWS_8MP,\
}
#define TIMING_STROBE_PROG_US 10 /* Min time to blow a fuse */
#define TIMING_STROBE_READ_NS 37 /* Min time before read */
#define TIMING_RELAX_NS 17
#define DEF_FSOURCE 1001 /* > 1000 ns */
#define DEF_STROBE_PROG 10000 /* IPG clocks */
#define IMX_OCOTP_WR_UNLOCK 0x3E770000
#define IMX_OCOTP_READ_LOCKED_VAL 0xBADABADA
static DEFINE_MUTEX(ocotp_mutex);
struct ocotp_priv {
struct device *dev;
struct clk *clk;
void __iomem *base;
const struct ocotp_params *params;
struct nvmem_config *config;
};
struct ocotp_ctrl_reg {
u32 bm_addr;
u32 bm_busy;
u32 bm_error;
u32 bm_rel_shadows;
};
struct ocotp_params {
unsigned int nregs;
unsigned int bank_address_words;
void (*set_timing)(struct ocotp_priv *priv);
struct ocotp_ctrl_reg ctrl;
};
static int imx_ocotp_wait_for_busy(struct ocotp_priv *priv, u32 flags)
{
int count;
u32 c, mask;
u32 bm_ctrl_busy, bm_ctrl_error;
void __iomem *base = priv->base;
bm_ctrl_busy = priv->params->ctrl.bm_busy;
bm_ctrl_error = priv->params->ctrl.bm_error;
mask = bm_ctrl_busy | bm_ctrl_error | flags;
for (count = 10000; count >= 0; count--) {
c = readl(base + IMX_OCOTP_ADDR_CTRL);
if (!(c & mask))
break;
cpu_relax();
}
if (count < 0) {
if (c & bm_ctrl_error)
return -EPERM;
return -ETIMEDOUT;
}
return 0;
}
static void imx_ocotp_clr_err_if_set(struct ocotp_priv *priv)
{
u32 c, bm_ctrl_error;
void __iomem *base = priv->base;
bm_ctrl_error = priv->params->ctrl.bm_error;
c = readl(base + IMX_OCOTP_ADDR_CTRL);
if (!(c & bm_ctrl_error))
return;
writel(bm_ctrl_error, base + IMX_OCOTP_ADDR_CTRL_CLR);
}
static int imx_ocotp_read(void *context, unsigned int offset,
void *val, size_t bytes)
{
struct ocotp_priv *priv = context;
unsigned int count;
u8 *buf, *p;
int i, ret;
u32 index, num_bytes;
index = offset >> 2;
num_bytes = round_up((offset % 4) + bytes, 4);
count = num_bytes >> 2;
if (count > (priv->params->nregs - index))
count = priv->params->nregs - index;
p = kzalloc(num_bytes, GFP_KERNEL);
if (!p)
return -ENOMEM;
mutex_lock(&ocotp_mutex);
buf = p;
ret = clk_prepare_enable(priv->clk);
if (ret < 0) {
mutex_unlock(&ocotp_mutex);
dev_err(priv->dev, "failed to prepare/enable ocotp clk\n");
kfree(p);
return ret;
}
ret = imx_ocotp_wait_for_busy(priv, 0);
if (ret < 0) {
dev_err(priv->dev, "timeout during read setup\n");
goto read_end;
}
for (i = index; i < (index + count); i++) {
*(u32 *)buf = readl(priv->base + IMX_OCOTP_OFFSET_B0W0 +
i * IMX_OCOTP_OFFSET_PER_WORD);
if (*((u32 *)buf) == IMX_OCOTP_READ_LOCKED_VAL)
imx_ocotp_clr_err_if_set(priv);
buf += 4;
}
index = offset % 4;
memcpy(val, &p[index], bytes);
read_end:
clk_disable_unprepare(priv->clk);
mutex_unlock(&ocotp_mutex);
kfree(p);
return ret;
}
static int imx_ocotp_cell_pp(void *context, const char *id, int index,
unsigned int offset, void *data, size_t bytes)
{
u8 *buf = data;
int i;
if (id && !strcmp(id, "mac-address"))
for (i = 0; i < bytes / 2; i++)
swap(buf[i], buf[bytes - i - 1]);
return 0;
}
static void imx_ocotp_set_imx6_timing(struct ocotp_priv *priv)
{
unsigned long clk_rate;
unsigned long strobe_read, relax, strobe_prog;
u32 timing;
clk_rate = clk_get_rate(priv->clk);
relax = DIV_ROUND_UP(clk_rate * TIMING_RELAX_NS, 1000000000) - 1;
strobe_read = DIV_ROUND_UP(clk_rate * TIMING_STROBE_READ_NS,
1000000000);
strobe_read += 2 * (relax + 1) - 1;
strobe_prog = DIV_ROUND_CLOSEST(clk_rate * TIMING_STROBE_PROG_US,
1000000);
strobe_prog += 2 * (relax + 1) - 1;
timing = readl(priv->base + IMX_OCOTP_ADDR_TIMING) & 0x0FC00000;
timing |= strobe_prog & 0x00000FFF;
timing |= (relax << 12) & 0x0000F000;
timing |= (strobe_read << 16) & 0x003F0000;
writel(timing, priv->base + IMX_OCOTP_ADDR_TIMING);
}
static void imx_ocotp_set_imx7_timing(struct ocotp_priv *priv)
{
unsigned long clk_rate;
u64 fsource, strobe_prog;
u32 timing;
clk_rate = clk_get_rate(priv->clk);
fsource = DIV_ROUND_UP_ULL((u64)clk_rate * DEF_FSOURCE,
NSEC_PER_SEC) + 1;
strobe_prog = DIV_ROUND_CLOSEST_ULL((u64)clk_rate * DEF_STROBE_PROG,
NSEC_PER_SEC) + 1;
timing = strobe_prog & 0x00000FFF;
timing |= (fsource << 12) & 0x000FF000;
writel(timing, priv->base + IMX_OCOTP_ADDR_TIMING);
}
static int imx_ocotp_write(void *context, unsigned int offset, void *val,
size_t bytes)
{
struct ocotp_priv *priv = context;
u32 *buf = val;
int ret;
u32 ctrl;
u8 waddr;
u8 word = 0;
if ((bytes != priv->config->word_size) ||
(offset % priv->config->word_size))
return -EINVAL;
mutex_lock(&ocotp_mutex);
ret = clk_prepare_enable(priv->clk);
if (ret < 0) {
mutex_unlock(&ocotp_mutex);
dev_err(priv->dev, "failed to prepare/enable ocotp clk\n");
return ret;
}
priv->params->set_timing(priv);
ret = imx_ocotp_wait_for_busy(priv, 0);
if (ret < 0) {
dev_err(priv->dev, "timeout during timing setup\n");
goto write_end;
}
if (priv->params->bank_address_words != 0) {
offset = offset / priv->config->word_size;
waddr = offset / priv->params->bank_address_words;
word = offset & (priv->params->bank_address_words - 1);
} else {
waddr = offset / 4;
}
ctrl = readl(priv->base + IMX_OCOTP_ADDR_CTRL);
ctrl &= ~priv->params->ctrl.bm_addr;
ctrl |= waddr & priv->params->ctrl.bm_addr;
ctrl |= IMX_OCOTP_WR_UNLOCK;
writel(ctrl, priv->base + IMX_OCOTP_ADDR_CTRL);
if (priv->params->bank_address_words != 0) {
switch (word) {
case 0:
writel(0, priv->base + IMX_OCOTP_ADDR_DATA1);
writel(0, priv->base + IMX_OCOTP_ADDR_DATA2);
writel(0, priv->base + IMX_OCOTP_ADDR_DATA3);
writel(*buf, priv->base + IMX_OCOTP_ADDR_DATA0);
break;
case 1:
writel(*buf, priv->base + IMX_OCOTP_ADDR_DATA1);
writel(0, priv->base + IMX_OCOTP_ADDR_DATA2);
writel(0, priv->base + IMX_OCOTP_ADDR_DATA3);
writel(0, priv->base + IMX_OCOTP_ADDR_DATA0);
break;
case 2:
writel(0, priv->base + IMX_OCOTP_ADDR_DATA1);
writel(*buf, priv->base + IMX_OCOTP_ADDR_DATA2);
writel(0, priv->base + IMX_OCOTP_ADDR_DATA3);
writel(0, priv->base + IMX_OCOTP_ADDR_DATA0);
break;
case 3:
writel(0, priv->base + IMX_OCOTP_ADDR_DATA1);
writel(0, priv->base + IMX_OCOTP_ADDR_DATA2);
writel(*buf, priv->base + IMX_OCOTP_ADDR_DATA3);
writel(0, priv->base + IMX_OCOTP_ADDR_DATA0);
break;
}
} else {
writel(*buf, priv->base + IMX_OCOTP_ADDR_DATA0);
}
ret = imx_ocotp_wait_for_busy(priv, 0);
if (ret < 0) {
if (ret == -EPERM) {
dev_err(priv->dev, "failed write to locked region");
imx_ocotp_clr_err_if_set(priv);
} else {
dev_err(priv->dev, "timeout during data write\n");
}
goto write_end;
}
udelay(2);
writel(priv->params->ctrl.bm_rel_shadows,
priv->base + IMX_OCOTP_ADDR_CTRL_SET);
ret = imx_ocotp_wait_for_busy(priv,
priv->params->ctrl.bm_rel_shadows);
if (ret < 0)
dev_err(priv->dev, "timeout during shadow register reload\n");
write_end:
clk_disable_unprepare(priv->clk);
mutex_unlock(&ocotp_mutex);
return ret < 0 ? ret : bytes;
}
static struct nvmem_config imx_ocotp_nvmem_config = {
.name = "imx-ocotp",
.read_only = false,
.word_size = 4,
.stride = 1,
.reg_read = imx_ocotp_read,
.reg_write = imx_ocotp_write,
};
static const struct ocotp_params imx6q_params = {
.nregs = 128,
.bank_address_words = 0,
.set_timing = imx_ocotp_set_imx6_timing,
.ctrl = IMX_OCOTP_BM_CTRL_DEFAULT,
};
static const struct ocotp_params imx6sl_params = {
.nregs = 64,
.bank_address_words = 0,
.set_timing = imx_ocotp_set_imx6_timing,
.ctrl = IMX_OCOTP_BM_CTRL_DEFAULT,
};
static const struct ocotp_params imx6sll_params = {
.nregs = 80,
.bank_address_words = 0,
.set_timing = imx_ocotp_set_imx6_timing,
.ctrl = IMX_OCOTP_BM_CTRL_DEFAULT,
};
static const struct ocotp_params imx6sx_params = {
.nregs = 128,
.bank_address_words = 0,
.set_timing = imx_ocotp_set_imx6_timing,
.ctrl = IMX_OCOTP_BM_CTRL_DEFAULT,
};
static const struct ocotp_params imx6ul_params = {
.nregs = 144,
.bank_address_words = 0,
.set_timing = imx_ocotp_set_imx6_timing,
.ctrl = IMX_OCOTP_BM_CTRL_DEFAULT,
};
static const struct ocotp_params imx6ull_params = {
.nregs = 80,
.bank_address_words = 0,
.set_timing = imx_ocotp_set_imx6_timing,
.ctrl = IMX_OCOTP_BM_CTRL_DEFAULT,
};
static const struct ocotp_params imx7d_params = {
.nregs = 64,
.bank_address_words = 4,
.set_timing = imx_ocotp_set_imx7_timing,
.ctrl = IMX_OCOTP_BM_CTRL_DEFAULT,
};
static const struct ocotp_params imx7ulp_params = {
.nregs = 256,
.bank_address_words = 0,
.ctrl = IMX_OCOTP_BM_CTRL_DEFAULT,
};
static const struct ocotp_params imx8mq_params = {
.nregs = 256,
.bank_address_words = 0,
.set_timing = imx_ocotp_set_imx6_timing,
.ctrl = IMX_OCOTP_BM_CTRL_DEFAULT,
};
static const struct ocotp_params imx8mm_params = {
.nregs = 256,
.bank_address_words = 0,
.set_timing = imx_ocotp_set_imx6_timing,
.ctrl = IMX_OCOTP_BM_CTRL_DEFAULT,
};
static const struct ocotp_params imx8mn_params = {
.nregs = 256,
.bank_address_words = 0,
.set_timing = imx_ocotp_set_imx6_timing,
.ctrl = IMX_OCOTP_BM_CTRL_DEFAULT,
};
static const struct ocotp_params imx8mp_params = {
.nregs = 384,
.bank_address_words = 0,
.set_timing = imx_ocotp_set_imx6_timing,
.ctrl = IMX_OCOTP_BM_CTRL_8MP,
};
static const struct of_device_id imx_ocotp_dt_ids[] = {
{ .compatible = "fsl,imx6q-ocotp", .data = &imx6q_params },
{ .compatible = "fsl,imx6sl-ocotp", .data = &imx6sl_params },
{ .compatible = "fsl,imx6sx-ocotp", .data = &imx6sx_params },
{ .compatible = "fsl,imx6ul-ocotp", .data = &imx6ul_params },
{ .compatible = "fsl,imx6ull-ocotp", .data = &imx6ull_params },
{ .compatible = "fsl,imx7d-ocotp", .data = &imx7d_params },
{ .compatible = "fsl,imx6sll-ocotp", .data = &imx6sll_params },
{ .compatible = "fsl,imx7ulp-ocotp", .data = &imx7ulp_params },
{ .compatible = "fsl,imx8mq-ocotp", .data = &imx8mq_params },
{ .compatible = "fsl,imx8mm-ocotp", .data = &imx8mm_params },
{ .compatible = "fsl,imx8mn-ocotp", .data = &imx8mn_params },
{ .compatible = "fsl,imx8mp-ocotp", .data = &imx8mp_params },
{ },
};
MODULE_DEVICE_TABLE(of, imx_ocotp_dt_ids);
static void imx_ocotp_fixup_cell_info(struct nvmem_device *nvmem,
struct nvmem_layout *layout,
struct nvmem_cell_info *cell)
{
cell->read_post_process = imx_ocotp_cell_pp;
}
static struct nvmem_layout imx_ocotp_layout = {
.fixup_cell_info = imx_ocotp_fixup_cell_info,
};
static int imx_ocotp_probe(struct platform_device *pdev)
{
struct device *dev = &pdev->dev;
struct ocotp_priv *priv;
struct nvmem_device *nvmem;
priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
if (!priv)
return -ENOMEM;
priv->dev = dev;
priv->base = devm_platform_ioremap_resource(pdev, 0);
if (IS_ERR(priv->base))
return PTR_ERR(priv->base);
priv->clk = devm_clk_get(dev, NULL);
if (IS_ERR(priv->clk))
return PTR_ERR(priv->clk);
priv->params = of_device_get_match_data(&pdev->dev);
imx_ocotp_nvmem_config.size = 4 * priv->params->nregs;
imx_ocotp_nvmem_config.dev = dev;
imx_ocotp_nvmem_config.priv = priv;
imx_ocotp_nvmem_config.layout = &imx_ocotp_layout;
priv->config = &imx_ocotp_nvmem_config;
clk_prepare_enable(priv->clk);
imx_ocotp_clr_err_if_set(priv);
clk_disable_unprepare(priv->clk);
nvmem = devm_nvmem_register(dev, &imx_ocotp_nvmem_config);
return PTR_ERR_OR_ZERO(nvmem);
}
static struct platform_driver imx_ocotp_driver = {
.probe = imx_ocotp_probe,
.driver = {
.name = "imx_ocotp",
.of_match_table = imx_ocotp_dt_ids,
},
};
module_platform_driver(imx_ocotp_driver);
MODULE_AUTHOR("Philipp Zabel <p.zabel@pengutronix.de>");
MODULE_DESCRIPTION("i.MX6/i.MX7 OCOTP fuse box driver");
MODULE_LICENSE("GPL v2"