From: PrasannaKumar Muralidharan prasannatsmkumar@gmail.com

This patch brings support for the JZ4780 efuse. Currently it only exposes a read only access to the entire 8K bits efuse memory and nvmem cells.

Tested-by: Mathieu Malaterre malat@debian.org Signed-off-by: PrasannaKumar Muralidharan prasannatsmkumar@gmail.com Signed-off-by: Mathieu Malaterre malat@debian.org Signed-off-by: H. Nikolaus Schaller hns@goldelico.com Signed-off-by: Paul Cercueil paul@crapouillou.net --- drivers/nvmem/Kconfig | 10 ++ drivers/nvmem/Makefile | 2 + drivers/nvmem/jz4780-efuse.c | 229 +++++++++++++++++++++++++++++++++++ 3 files changed, 241 insertions(+) create mode 100644 drivers/nvmem/jz4780-efuse.c

diff --git a/drivers/nvmem/Kconfig b/drivers/nvmem/Kconfig index 35efab1ba8d9..8143e6e1dd82 100644 --- a/drivers/nvmem/Kconfig +++ b/drivers/nvmem/Kconfig @@ -55,6 +55,16 @@ config NVMEM_IMX_OCOTP_SCU This is a driver for the SCU On-Chip OTP Controller (OCOTP) available on i.MX8 SoCs.

+config JZ4780_EFUSE + tristate "JZ4780 EFUSE Memory Support" + depends on MACH_INGENIC || COMPILE_TEST + depends on HAS_IOMEM + help + Say Y here to include support for JZ4780 efuse memory found on + all JZ4780 SoC based devices. + To compile this driver as a module, choose M here: the module + will be called nvmem_jz4780_efuse. + config NVMEM_LPC18XX_EEPROM tristate "NXP LPC18XX EEPROM Memory Support" depends on ARCH_LPC18XX || COMPILE_TEST diff --git a/drivers/nvmem/Makefile b/drivers/nvmem/Makefile index 6b466cd1427b..65a268d17807 100644 --- a/drivers/nvmem/Makefile +++ b/drivers/nvmem/Makefile @@ -18,6 +18,8 @@ obj-$(CONFIG_NVMEM_IMX_OCOTP) += nvmem-imx-ocotp.o nvmem-imx-ocotp-y := imx-ocotp.o obj-$(CONFIG_NVMEM_IMX_OCOTP_SCU) += nvmem-imx-ocotp-scu.o nvmem-imx-ocotp-scu-y := imx-ocotp-scu.o +obj-$(CONFIG_JZ4780_EFUSE) += nvmem_jz4780_efuse.o +nvmem_jz4780_efuse-y := jz4780-efuse.o obj-$(CONFIG_NVMEM_LPC18XX_EEPROM) += nvmem_lpc18xx_eeprom.o nvmem_lpc18xx_eeprom-y := lpc18xx_eeprom.o obj-$(CONFIG_NVMEM_LPC18XX_OTP) += nvmem_lpc18xx_otp.o diff --git a/drivers/nvmem/jz4780-efuse.c b/drivers/nvmem/jz4780-efuse.c new file mode 100644 index 000000000000..08b63de0e9cc --- /dev/null +++ b/drivers/nvmem/jz4780-efuse.c @@ -0,0 +1,229 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * JZ4780 EFUSE Memory Support driver + * + * Copyright (c) 2017 PrasannaKumar Muralidharan prasannatsmkumar@gmail.com + * Copyright (c) 2020 H. Nikolaus Schaller hns@goldelico.com + */ + +/* + * Currently supports JZ4780 efuse which has 8K programmable bit. + * Efuse is separated into seven segments as below: + * + * ----------------------------------------------------------------------- + * | 64 bit | 128 bit | 128 bit | 3520 bit | 8 bit | 2296 bit | 2048 bit | + * ----------------------------------------------------------------------- + * + * The rom itself is accessed using a 9 bit address line and an 8 word wide bus + * which reads/writes based on strobes. The strobe is configured in the config + * register and is based on number of cycles of the bus clock. + * + * Driver supports read only as the writes are done in the Factory. + */ + +#include <linux/bitops.h> +#include <linux/clk.h> +#include <linux/module.h> +#include <linux/nvmem-provider.h> +#include <linux/of.h> +#include <linux/platform_device.h> +#include <linux/regmap.h> +#include <linux/timer.h> + +#define JZ_EFUCTRL (0x0) /* Control Register */ +#define JZ_EFUCFG (0x4) /* Configure Register*/ +#define JZ_EFUSTATE (0x8) /* Status Register */ +#define JZ_EFUDATA(n) (0xC + (n) * 4) + +#define EFUCTRL_ADDR_MASK 0x3FF +#define EFUCTRL_ADDR_SHIFT 21 +#define EFUCTRL_LEN_MASK 0x1F +#define EFUCTRL_LEN_SHIFT 16 +#define EFUCTRL_PG_EN BIT(15) +#define EFUCTRL_WR_EN BIT(1) +#define EFUCTRL_RD_EN BIT(0) + +#define EFUCFG_INT_EN BIT(31) +#define EFUCFG_RD_ADJ_MASK 0xF +#define EFUCFG_RD_ADJ_SHIFT 20 +#define EFUCFG_RD_STR_MASK 0xF +#define EFUCFG_RD_STR_SHIFT 16 +#define EFUCFG_WR_ADJ_MASK 0xF +#define EFUCFG_WR_ADJ_SHIFT 12 +#define EFUCFG_WR_STR_MASK 0xFFF +#define EFUCFG_WR_STR_SHIFT 0 + +#define EFUSTATE_WR_DONE BIT(1) +#define EFUSTATE_RD_DONE BIT(0) + +struct jz4780_efuse { + struct device *dev; + struct regmap *map; + struct clk *clk; + unsigned int rd_adj; + unsigned int rd_strobe; +}; + +/* We read 32 byte chunks to avoid complexity in the driver. */ +static int jz4780_efuse_read_32bytes(struct jz4780_efuse *efuse, char *buf, + unsigned int addr) +{ + unsigned int tmp; + u32 ctrl; + int ret; + const int size = 32; + + ctrl = (addr << EFUCTRL_ADDR_SHIFT) + | ((size - 1) << EFUCTRL_LEN_SHIFT) + | EFUCTRL_RD_EN; + + regmap_update_bits(efuse->map, JZ_EFUCTRL, + (EFUCTRL_ADDR_MASK << EFUCTRL_ADDR_SHIFT) | + (EFUCTRL_LEN_MASK << EFUCTRL_LEN_SHIFT) | + EFUCTRL_PG_EN | EFUCTRL_WR_EN | EFUCTRL_RD_EN, ctrl); + + ret = regmap_read_poll_timeout(efuse->map, JZ_EFUSTATE, + tmp, tmp & EFUSTATE_RD_DONE, + 1 * MSEC_PER_SEC, 50 * MSEC_PER_SEC); + if (ret < 0) { + dev_err(efuse->dev, "Time out while reading efuse data"); + return ret; + } + + return regmap_bulk_read(efuse->map, JZ_EFUDATA(0), + buf, size / sizeof(u32)); +} + +/* main entry point */ +static int jz4780_efuse_read(void *context, unsigned int offset, + void *val, size_t bytes) +{ + struct jz4780_efuse *efuse = context; + int ret; + const int size = 32; + + while (bytes > 0) { + unsigned int start = offset & ~(size - 1); + unsigned int chunk = min(bytes, (start + size) - offset); + + if (start == offset && chunk == size) { + ret = jz4780_efuse_read_32bytes(efuse, val, start); + if (ret < 0) + return ret; + + } else { + char buf[32]; + + ret = jz4780_efuse_read_32bytes(efuse, buf, start); + if (ret < 0) + return ret; + + memcpy(val, &buf[offset - start], chunk); + } + + val += chunk; + offset += chunk; + bytes -= chunk; + } + + return 0; +} + +static struct nvmem_config jz4780_efuse_nvmem_config __initdata = { + .name = "jz4780-efuse", + .size = 1024, + .word_size = 1, + .stride = 1, + .owner = THIS_MODULE, + .reg_read = jz4780_efuse_read, +}; + +static const struct regmap_config jz4780_efuse_regmap_config = { + .reg_bits = 32, + .val_bits = 32, + .reg_stride = 4, + .max_register = JZ_EFUDATA(7), +}; + +static int jz4780_efuse_probe(struct platform_device *pdev) +{ + struct nvmem_device *nvmem; + struct jz4780_efuse *efuse; + struct nvmem_config cfg; + unsigned long clk_rate; + struct device *dev = &pdev->dev; + void __iomem *regs; + + efuse = devm_kzalloc(dev, sizeof(*efuse), GFP_KERNEL); + if (!efuse) + return -ENOMEM; + + regs = devm_platform_ioremap_resource(pdev, 0); + if (IS_ERR(regs)) + return PTR_ERR(regs); + + efuse->map = devm_regmap_init_mmio(dev, regs, + &jz4780_efuse_regmap_config); + if (IS_ERR(efuse->map)) + return PTR_ERR(efuse->map); + + efuse->clk = devm_clk_get(&pdev->dev, NULL); + if (IS_ERR(efuse->clk)) + return PTR_ERR(efuse->clk); + + clk_rate = clk_get_rate(efuse->clk); + + efuse->dev = dev; + /* + * rd_adj and rd_strobe are 4 bit values + * bus clk period * (rd_adj + 1) > 6.5ns + * bus clk period * (rd_adj + 5 + rd_strobe) > 35ns + */ + efuse->rd_adj = (((6500 * (clk_rate / 1000000)) / 1000000) + 1) - 1; + efuse->rd_strobe = ((((35000 * (clk_rate / 1000000)) / 1000000) + 1) + - 5 - efuse->rd_adj); + + if (efuse->rd_adj > 0x1F || efuse->rd_strobe > 0x1F) { + dev_err(&pdev->dev, "Cannot set clock configuration\n"); + return -EINVAL; + } + + regmap_update_bits(efuse->map, JZ_EFUCFG, + (EFUCFG_RD_ADJ_MASK << EFUCFG_RD_ADJ_SHIFT) | + (EFUCFG_RD_STR_MASK << EFUCFG_RD_STR_SHIFT), + (efuse->rd_adj << EFUCFG_RD_ADJ_SHIFT) | + (efuse->rd_strobe << EFUCFG_RD_STR_SHIFT)); + + cfg = jz4780_efuse_nvmem_config; + cfg.dev = &pdev->dev; + cfg.priv = efuse; + + nvmem = devm_nvmem_register(dev, &cfg); + if (IS_ERR(nvmem)) + return PTR_ERR(nvmem); + + platform_set_drvdata(pdev, nvmem); + + return 0; +} + +static const struct of_device_id jz4780_efuse_match[] = { + { .compatible = "ingenic,jz4780-efuse" }, + { /* sentinel */ }, +}; +MODULE_DEVICE_TABLE(of, jz4780_efuse_match); + +static struct platform_driver jz4780_efuse_driver = { + .probe = jz4780_efuse_probe, + .driver = { + .name = "jz4780-efuse", + .of_match_table = jz4780_efuse_match, + }, +}; +module_platform_driver(jz4780_efuse_driver); + +MODULE_AUTHOR("PrasannaKumar Muralidharan prasannatsmkumar@gmail.com"); +MODULE_AUTHOR("H. Nikolaus Schaller hns@goldelico.com"); +MODULE_AUTHOR("Paul Cercueil paul@crapouillou.net"); +MODULE_DESCRIPTION("Ingenic JZ4780 efuse driver"); +MODULE_LICENSE("GPL v2");

From: PrasannaKumar Muralidharan prasannatsmkumar@gmail.com

This patch brings support for the JZ4780 efuse. Currently it only expose a read only access to the entire 8K bits efuse memory.

Tested-by: Mathieu Malaterre malat@debian.org Signed-off-by: PrasannaKumar Muralidharan prasannatsmkumar@gmail.com Signed-off-by: Mathieu Malaterre malat@debian.org --- MAINTAINERS | 5 +++++ 1 file changed, 5 insertions(+)

diff --git a/MAINTAINERS b/MAINTAINERS index a0d86490c2c6..5bab216d8fe9 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -8270,6 +8270,11 @@ M: Zubair Lutfullah Kakakhel Zubair.Kakakhel@imgtec.com S: Maintained F: drivers/dma/dma-jz4780.c

+INGENIC JZ4780 EFUSE Driver +M: PrasannaKumar Muralidharan prasannatsmkumar@gmail.com +S: Maintained +F: drivers/nvmem/jz4780-efuse.c + INGENIC JZ4780 NAND DRIVER M: Harvey Hunt harveyhuntnexus@gmail.com L: linux-mtd@lists.infradead.org

There is a unique MAC address programmed into the eFuses of the JZ4780 chip in the CI20 factory. By using this for initializing the DM9000 Ethernet controller, every CI20 board has an individual - but stable - MAC address and DHCP can assign stable IP addresses.

Signed-off-by: H. Nikolaus Schaller hns@goldelico.com --- arch/mips/boot/dts/ingenic/ci20.dts | 3 +++ 1 file changed, 3 insertions(+)

diff --git a/arch/mips/boot/dts/ingenic/ci20.dts b/arch/mips/boot/dts/ingenic/ci20.dts index 37b93166bf22..6dc1f9eeff00 100644 --- a/arch/mips/boot/dts/ingenic/ci20.dts +++ b/arch/mips/boot/dts/ingenic/ci20.dts @@ -355,6 +355,9 @@

interrupt-parent = <&gpe>; interrupts = <19 4>; + + nvmem-cells = <&eth0_addr>; + nvmem-cell-names = "mac-address"; }; };