--- /dev/null
+// SPDX-License-Identifier: GPL-2.0
+// Copyright (C) 2022-2023 Microchip Technology Inc.
+// PCI1xxxx OTP/EEPROM driver
+
+#include <linux/auxiliary_bus.h>
+#include <linux/device.h>
+#include <linux/iopoll.h>
+#include <linux/module.h>
+#include <linux/nvmem-provider.h>
+
+#include "mchp_pci1xxxx_gp.h"
+
+#define AUX_DRIVER_NAME "PCI1xxxxOTPE2P"
+#define OTP_NAME "pci1xxxx_otp"
+
+#define PERI_PF3_SYSTEM_REG_ADDR_BASE 0x2000
+#define PERI_PF3_SYSTEM_REG_LENGTH 0x4000
+
+#define OTP_SIZE_BYTES 8192
+
+#define CONFIG_REG_ADDR_BASE 0
+#define OTP_REG_ADDR_BASE 0x1000
+
+#define MMAP_OTP_OFFSET(x) (OTP_REG_ADDR_BASE + (x))
+#define MMAP_CFG_OFFSET(x) (CONFIG_REG_ADDR_BASE + (x))
+
+#define STATUS_READ_DELAY_US 1
+#define STATUS_READ_TIMEOUT_US 20000
+
+#define OTP_ADDR_HIGH_OFFSET 0x04
+#define OTP_ADDR_LOW_OFFSET 0x08
+#define OTP_PRGM_DATA_OFFSET 0x10
+#define OTP_PRGM_MODE_OFFSET 0x14
+#define OTP_RD_DATA_OFFSET 0x18
+#define OTP_FUNC_CMD_OFFSET 0x20
+#define OTP_CMD_GO_OFFSET 0x28
+#define OTP_PASS_FAIL_OFFSET 0x2C
+#define OTP_STATUS_OFFSET 0x30
+
+#define OTP_FUNC_RD_BIT BIT(0)
+#define OTP_FUNC_PGM_BIT BIT(1)
+#define OTP_CMD_GO_BIT BIT(0)
+#define OTP_STATUS_BUSY_BIT BIT(0)
+#define OTP_PGM_MODE_BYTE_BIT BIT(0)
+#define OTP_FAIL_BIT BIT(0)
+
+#define OTP_PWR_DN_BIT BIT(0)
+#define OTP_PWR_DN_OFFSET 0x00
+
+#define CFG_SYS_LOCK_OFFSET 0xA0
+#define CFG_SYS_LOCK_PF3 BIT(5)
+
+#define BYTE_LOW (GENMASK(7, 0))
+#define BYTE_HIGH (GENMASK(12, 8))
+
+struct pci1xxxx_otp_eeprom_device {
+ struct auxiliary_device *pdev;
+ void __iomem *reg_base;
+ struct nvmem_config nvmem_config_otp;
+ struct nvmem_device *nvmem_otp;
+};
+
+static int set_sys_lock(struct pci1xxxx_otp_eeprom_device *priv)
+{
+ void __iomem *sys_lock = priv->reg_base +
+ MMAP_CFG_OFFSET(CFG_SYS_LOCK_OFFSET);
+ u8 data;
+
+ writel(CFG_SYS_LOCK_PF3, sys_lock);
+ data = readl(sys_lock);
+ if (data != CFG_SYS_LOCK_PF3)
+ return -EPERM;
+
+ return 0;
+}
+
+static void release_sys_lock(struct pci1xxxx_otp_eeprom_device *priv)
+{
+ void __iomem *sys_lock = priv->reg_base +
+ MMAP_CFG_OFFSET(CFG_SYS_LOCK_OFFSET);
+ writel(0, sys_lock);
+}
+
+static void otp_device_set_address(struct pci1xxxx_otp_eeprom_device *priv,
+ u16 address)
+{
+ u16 lo, hi;
+
+ lo = address & BYTE_LOW;
+ hi = (address & BYTE_HIGH) >> 8;
+ writew(lo, priv->reg_base + MMAP_OTP_OFFSET(OTP_ADDR_LOW_OFFSET));
+ writew(hi, priv->reg_base + MMAP_OTP_OFFSET(OTP_ADDR_HIGH_OFFSET));
+}
+
+static int pci1xxxx_otp_read(void *priv_t, unsigned int off,
+ void *buf_t, size_t count)
+{
+ struct pci1xxxx_otp_eeprom_device *priv = priv_t;
+ void __iomem *rb = priv->reg_base;
+ char *buf = buf_t;
+ u32 regval;
+ u32 byte;
+ int ret;
+ u8 data;
+
+ if (off >= priv->nvmem_config_otp.size)
+ return -EFAULT;
+
+ if ((off + count) > priv->nvmem_config_otp.size)
+ count = priv->nvmem_config_otp.size - off;
+
+ ret = set_sys_lock(priv);
+ if (ret)
+ return ret;
+
+ for (byte = 0; byte < count; byte++) {
+ otp_device_set_address(priv, (u16)(off + byte));
+ data = readl(rb + MMAP_OTP_OFFSET(OTP_FUNC_CMD_OFFSET));
+ writel(data | OTP_FUNC_RD_BIT,
+ rb + MMAP_OTP_OFFSET(OTP_FUNC_CMD_OFFSET));
+ data = readl(rb + MMAP_OTP_OFFSET(OTP_CMD_GO_OFFSET));
+ writel(data | OTP_CMD_GO_BIT,
+ rb + MMAP_OTP_OFFSET(OTP_CMD_GO_OFFSET));
+
+ ret = read_poll_timeout(readl, regval,
+ !(regval & OTP_STATUS_BUSY_BIT),
+ STATUS_READ_DELAY_US,
+ STATUS_READ_TIMEOUT_US, true,
+ rb + MMAP_OTP_OFFSET(OTP_STATUS_OFFSET));
+
+ data = readl(rb + MMAP_OTP_OFFSET(OTP_PASS_FAIL_OFFSET));
+ if (ret < 0 || data & OTP_FAIL_BIT) {
+ ret = -EIO;
+ goto error;
+ }
+
+ buf[byte] = readl(rb + MMAP_OTP_OFFSET(OTP_RD_DATA_OFFSET));
+ }
+ ret = byte;
+error:
+ release_sys_lock(priv);
+ return ret;
+}
+
+static int pci1xxxx_otp_write(void *priv_t, unsigned int off,
+ void *value_t, size_t count)
+{
+ struct pci1xxxx_otp_eeprom_device *priv = priv_t;
+ void __iomem *rb = priv->reg_base;
+ char *value = value_t;
+ u32 regval;
+ u32 byte;
+ int ret;
+ u8 data;
+
+ if (off >= priv->nvmem_config_otp.size)
+ return -EFAULT;
+
+ if ((off + count) > priv->nvmem_config_otp.size)
+ count = priv->nvmem_config_otp.size - off;
+
+ ret = set_sys_lock(priv);
+ if (ret)
+ return ret;
+
+ for (byte = 0; byte < count; byte++) {
+ otp_device_set_address(priv, (u16)(off + byte));
+
+ /*
+ * Set OTP_PGM_MODE_BYTE command bit in OTP_PRGM_MODE register
+ * to enable Byte programming
+ */
+ data = readl(rb + MMAP_OTP_OFFSET(OTP_PRGM_MODE_OFFSET));
+ writel(data | OTP_PGM_MODE_BYTE_BIT,
+ rb + MMAP_OTP_OFFSET(OTP_PRGM_MODE_OFFSET));
+ writel(*(value + byte), rb + MMAP_OTP_OFFSET(OTP_PRGM_DATA_OFFSET));
+ data = readl(rb + MMAP_OTP_OFFSET(OTP_FUNC_CMD_OFFSET));
+ writel(data | OTP_FUNC_PGM_BIT,
+ rb + MMAP_OTP_OFFSET(OTP_FUNC_CMD_OFFSET));
+ data = readl(rb + MMAP_OTP_OFFSET(OTP_CMD_GO_OFFSET));
+ writel(data | OTP_CMD_GO_BIT,
+ rb + MMAP_OTP_OFFSET(OTP_CMD_GO_OFFSET));
+
+ ret = read_poll_timeout(readl, regval,
+ !(regval & OTP_STATUS_BUSY_BIT),
+ STATUS_READ_DELAY_US,
+ STATUS_READ_TIMEOUT_US, true,
+ rb + MMAP_OTP_OFFSET(OTP_STATUS_OFFSET));
+
+ data = readl(rb + MMAP_OTP_OFFSET(OTP_PASS_FAIL_OFFSET));
+ if (ret < 0 || data & OTP_FAIL_BIT) {
+ ret = -EIO;
+ goto error;
+ }
+ }
+ ret = byte;
+error:
+ release_sys_lock(priv);
+ return ret;
+}
+
+static int pci1xxxx_otp_eeprom_probe(struct auxiliary_device *aux_dev,
+ const struct auxiliary_device_id *id)
+{
+ struct auxiliary_device_wrapper *aux_dev_wrapper;
+ struct pci1xxxx_otp_eeprom_device *priv;
+ struct gp_aux_data_type *pdata;
+ int ret;
+ u8 data;
+
+ aux_dev_wrapper = container_of(aux_dev, struct auxiliary_device_wrapper,
+ aux_dev);
+ pdata = &aux_dev_wrapper->gp_aux_data;
+ if (!pdata)
+ return -EINVAL;
+
+ priv = devm_kzalloc(&aux_dev->dev, sizeof(*priv), GFP_KERNEL);
+ if (!priv)
+ return -ENOMEM;
+
+ priv->pdev = aux_dev;
+
+ if (!devm_request_mem_region(&aux_dev->dev, pdata->region_start +
+ PERI_PF3_SYSTEM_REG_ADDR_BASE,
+ PERI_PF3_SYSTEM_REG_LENGTH,
+ aux_dev->name))
+ return -ENOMEM;
+
+ priv->reg_base = devm_ioremap(&aux_dev->dev, pdata->region_start +
+ PERI_PF3_SYSTEM_REG_ADDR_BASE,
+ PERI_PF3_SYSTEM_REG_LENGTH);
+ if (!priv->reg_base)
+ return -ENOMEM;
+
+ ret = set_sys_lock(priv);
+ if (ret)
+ return ret;
+
+ /* Set OTP_PWR_DN to 0 to make OTP Operational */
+ data = readl(priv->reg_base + MMAP_OTP_OFFSET(OTP_PWR_DN_OFFSET));
+ writel(data & ~OTP_PWR_DN_BIT,
+ priv->reg_base + MMAP_OTP_OFFSET(OTP_PWR_DN_OFFSET));
+
+ dev_set_drvdata(&aux_dev->dev, priv);
+
+ release_sys_lock(priv);
+
+ priv->nvmem_config_otp.type = NVMEM_TYPE_OTP;
+ priv->nvmem_config_otp.name = OTP_NAME;
+ priv->nvmem_config_otp.dev = &aux_dev->dev;
+ priv->nvmem_config_otp.owner = THIS_MODULE;
+ priv->nvmem_config_otp.reg_read = pci1xxxx_otp_read;
+ priv->nvmem_config_otp.reg_write = pci1xxxx_otp_write;
+ priv->nvmem_config_otp.priv = priv;
+ priv->nvmem_config_otp.stride = 1;
+ priv->nvmem_config_otp.word_size = 1;
+ priv->nvmem_config_otp.size = OTP_SIZE_BYTES;
+
+ priv->nvmem_otp = devm_nvmem_register(&aux_dev->dev,
+ &priv->nvmem_config_otp);
+ if (!priv->nvmem_otp)
+ return -ENOMEM;
+
+ return ret;
+}
+
+static void pci1xxxx_otp_eeprom_remove(struct auxiliary_device *aux_dev)
+{
+ struct pci1xxxx_otp_eeprom_device *priv;
+ void __iomem *sys_lock;
+
+ priv = dev_get_drvdata(&aux_dev->dev);
+ sys_lock = priv->reg_base + MMAP_CFG_OFFSET(CFG_SYS_LOCK_OFFSET);
+ writel(CFG_SYS_LOCK_PF3, sys_lock);
+
+ /* Shut down OTP */
+ writel(OTP_PWR_DN_BIT,
+ priv->reg_base + MMAP_OTP_OFFSET(OTP_PWR_DN_OFFSET));
+
+ writel(0, sys_lock);
+}
+
+static const struct auxiliary_device_id pci1xxxx_otp_eeprom_auxiliary_id_table[] = {
+ {.name = "mchp_pci1xxxx_gp.gp_otp_e2p"},
+ {},
+};
+MODULE_DEVICE_TABLE(auxiliary, pci1xxxx_otp_eeprom_auxiliary_id_table);
+
+static struct auxiliary_driver pci1xxxx_otp_eeprom_driver = {
+ .driver = {
+ .name = AUX_DRIVER_NAME,
+ },
+ .probe = pci1xxxx_otp_eeprom_probe,
+ .remove = pci1xxxx_otp_eeprom_remove,
+ .id_table = pci1xxxx_otp_eeprom_auxiliary_id_table
+};
+module_auxiliary_driver(pci1xxxx_otp_eeprom_driver);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Kumaravel Thiagarajan <kumaravel.thiagarajan@microchip.com>");
+MODULE_AUTHOR("Tharun Kumar P <tharunkumar.pasumarthi@microchip.com>");
+MODULE_AUTHOR("Vaibhaav Ram T.L <vaibhaavram.tl@microchip.com>");
+MODULE_DESCRIPTION("Microchip Technology Inc. PCI1xxxx OTP EEPROM Programmer");
projects / platform / kernel / linux-starfive.git / commitdiff