linux-stable/drivers/nvmem/imx-ocotp-scu.c

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// SPDX-License-Identifier: GPL-2.0+
/*
* i.MX8 OCOTP fusebox driver
*
* Copyright 2019 NXP
*
* Peng Fan <peng.fan@nxp.com>
*/
#include <linux/arm-smccc.h>
#include <linux/firmware/imx/sci.h>
#include <linux/module.h>
#include <linux/nvmem-provider.h>
#include <linux/of.h>
#include <linux/platform_device.h>
#include <linux/slab.h>
#define IMX_SIP_OTP_WRITE 0xc200000B
enum ocotp_devtype {
IMX8QXP,
IMX8QM,
};
#define ECC_REGION BIT(0)
#define HOLE_REGION BIT(1)
struct ocotp_region {
u32 start;
u32 end;
u32 flag;
};
struct ocotp_devtype_data {
int devtype;
int nregs;
u32 num_region;
struct ocotp_region region[];
};
struct ocotp_priv {
struct device *dev;
const struct ocotp_devtype_data *data;
struct imx_sc_ipc *nvmem_ipc;
};
struct imx_sc_msg_misc_fuse_read {
struct imx_sc_rpc_msg hdr;
u32 word;
} __packed;
static DEFINE_MUTEX(scu_ocotp_mutex);
static struct ocotp_devtype_data imx8qxp_data = {
.devtype = IMX8QXP,
.nregs = 800,
.num_region = 3,
.region = {
{0x10, 0x10f, ECC_REGION},
{0x110, 0x21F, HOLE_REGION},
{0x220, 0x31F, ECC_REGION},
},
};
static struct ocotp_devtype_data imx8qm_data = {
.devtype = IMX8QM,
.nregs = 800,
.num_region = 2,
.region = {
{0x10, 0x10f, ECC_REGION},
{0x1a0, 0x1ff, ECC_REGION},
},
};
static bool in_hole(void *context, u32 index)
{
struct ocotp_priv *priv = context;
const struct ocotp_devtype_data *data = priv->data;
int i;
for (i = 0; i < data->num_region; i++) {
if (data->region[i].flag & HOLE_REGION) {
if ((index >= data->region[i].start) &&
(index <= data->region[i].end))
return true;
}
}
return false;
}
static bool in_ecc(void *context, u32 index)
{
struct ocotp_priv *priv = context;
const struct ocotp_devtype_data *data = priv->data;
int i;
for (i = 0; i < data->num_region; i++) {
if (data->region[i].flag & ECC_REGION) {
if ((index >= data->region[i].start) &&
(index <= data->region[i].end))
return true;
}
}
return false;
}
static int imx_sc_misc_otp_fuse_read(struct imx_sc_ipc *ipc, u32 word,
u32 *val)
{
struct imx_sc_msg_misc_fuse_read msg;
struct imx_sc_rpc_msg *hdr = &msg.hdr;
int ret;
hdr->ver = IMX_SC_RPC_VERSION;
hdr->svc = IMX_SC_RPC_SVC_MISC;
hdr->func = IMX_SC_MISC_FUNC_OTP_FUSE_READ;
hdr->size = 2;
msg.word = word;
ret = imx_scu_call_rpc(ipc, &msg, true);
if (ret)
return ret;
*val = msg.word;
return 0;
}
static int imx_scu_ocotp_read(void *context, unsigned int offset,
void *val, size_t bytes)
{
struct ocotp_priv *priv = context;
u32 count, index, num_bytes;
u32 *buf;
void *p;
int i, ret;
index = offset;
num_bytes = round_up(bytes, 4);
count = num_bytes >> 2;
if (count > (priv->data->nregs - index))
count = priv->data->nregs - index;
p = kzalloc(num_bytes, GFP_KERNEL);
if (!p)
return -ENOMEM;
mutex_lock(&scu_ocotp_mutex);
buf = p;
for (i = index; i < (index + count); i++) {
if (in_hole(context, i)) {
*buf++ = 0;
continue;
}
ret = imx_sc_misc_otp_fuse_read(priv->nvmem_ipc, i, buf);
if (ret) {
mutex_unlock(&scu_ocotp_mutex);
kfree(p);
return ret;
}
buf++;
}
memcpy(val, (u8 *)p, bytes);
mutex_unlock(&scu_ocotp_mutex);
kfree(p);
return 0;
}
static int imx_scu_ocotp_write(void *context, unsigned int offset,
void *val, size_t bytes)
{
struct ocotp_priv *priv = context;
struct arm_smccc_res res;
u32 *buf = val;
u32 tmp;
u32 index;
int ret;
/* allow only writing one complete OTP word at a time */
if (bytes != 4)
return -EINVAL;
index = offset;
if (in_hole(context, index))
return -EINVAL;
if (in_ecc(context, index)) {
pr_warn("ECC region, only program once\n");
mutex_lock(&scu_ocotp_mutex);
ret = imx_sc_misc_otp_fuse_read(priv->nvmem_ipc, index, &tmp);
mutex_unlock(&scu_ocotp_mutex);
if (ret)
return ret;
if (tmp) {
pr_warn("ECC region, already has value: %x\n", tmp);
return -EIO;
}
}
mutex_lock(&scu_ocotp_mutex);
arm_smccc_smc(IMX_SIP_OTP_WRITE, index, *buf, 0, 0, 0, 0, 0, &res);
mutex_unlock(&scu_ocotp_mutex);
return res.a0;
}
static struct nvmem_config imx_scu_ocotp_nvmem_config = {
.name = "imx-scu-ocotp",
nvmem: add explicit config option to read old syntax fixed OF cells Binding for fixed NVMEM cells defined directly as NVMEM device subnodes has been deprecated. It has been replaced by the "fixed-layout" NVMEM layout binding. New syntax is meant to be clearer and should help avoiding imprecise bindings. NVMEM subsystem already supports the new binding. It should be a good idea to limit support for old syntax to existing drivers that actually support & use it (we can't break backward compatibility!). That way we additionally encourage new bindings & drivers to ignore deprecated binding. It wasn't clear (to me) if rtc and w1 code actually uses old syntax fixed cells. I enabled them to don't risk any breakage. Signed-off-by: Rafał Miłecki <rafal@milecki.pl> [for meson-{efuse,mx-efuse}.c] Acked-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> [for mtk-efuse.c, nvmem/core.c, nvmem-provider.h] Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com> [MT8192, MT8195 Chromebooks] Tested-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com> [for microchip-otpc.c] Reviewed-by: Claudiu Beznea <claudiu.beznea@microchip.com> [SAMA7G5-EK] Tested-by: Claudiu Beznea <claudiu.beznea@microchip.com> Acked-by: Jernej Skrabec <jernej.skrabec@gmail.com> Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org> Link: https://lore.kernel.org/r/20231020105545.216052-3-srinivas.kandagatla@linaro.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-10-20 10:55:41 +00:00
.add_legacy_fixed_of_cells = true,
.read_only = false,
.word_size = 4,
.stride = 1,
.owner = THIS_MODULE,
.reg_read = imx_scu_ocotp_read,
.reg_write = imx_scu_ocotp_write,
};
static const struct of_device_id imx_scu_ocotp_dt_ids[] = {
{ .compatible = "fsl,imx8qxp-scu-ocotp", (void *)&imx8qxp_data },
{ .compatible = "fsl,imx8qm-scu-ocotp", (void *)&imx8qm_data },
{ },
};
MODULE_DEVICE_TABLE(of, imx_scu_ocotp_dt_ids);
static int imx_scu_ocotp_probe(struct platform_device *pdev)
{
struct device *dev = &pdev->dev;
struct ocotp_priv *priv;
struct nvmem_device *nvmem;
int ret;
priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
if (!priv)
return -ENOMEM;
ret = imx_scu_get_handle(&priv->nvmem_ipc);
if (ret)
return ret;
priv->data = of_device_get_match_data(dev);
priv->dev = dev;
imx_scu_ocotp_nvmem_config.size = 4 * priv->data->nregs;
imx_scu_ocotp_nvmem_config.dev = dev;
imx_scu_ocotp_nvmem_config.priv = priv;
nvmem = devm_nvmem_register(dev, &imx_scu_ocotp_nvmem_config);
return PTR_ERR_OR_ZERO(nvmem);
}
static struct platform_driver imx_scu_ocotp_driver = {
.probe = imx_scu_ocotp_probe,
.driver = {
.name = "imx_scu_ocotp",
.of_match_table = imx_scu_ocotp_dt_ids,
},
};
module_platform_driver(imx_scu_ocotp_driver);
MODULE_AUTHOR("Peng Fan <peng.fan@nxp.com>");
MODULE_DESCRIPTION("i.MX8 SCU OCOTP fuse box driver");
MODULE_LICENSE("GPL v2");