Added a misc driver to handle OTP memory in SiFive SoCs.
Signed-off-by: Pragnesh Patel pragnesh.patel@sifive.com Reviewed-by: Bin Meng bmeng.cn@gmail.com Tested-by: Bin Meng bmeng.cn@gmail.com Reviewed-by: Jagan Teki jagan@amarulasolutions.com Tested-by: Jagan Teki jagan@amarulasolutions.com --- drivers/misc/Kconfig | 7 + drivers/misc/Makefile | 1 + drivers/misc/sifive-otp.c | 275 ++++++++++++++++++++++++++++++++++++++ 3 files changed, 283 insertions(+) create mode 100644 drivers/misc/sifive-otp.c
diff --git a/drivers/misc/Kconfig b/drivers/misc/Kconfig index 81ed9eb209..6bb5bc77e9 100644 --- a/drivers/misc/Kconfig +++ b/drivers/misc/Kconfig @@ -68,6 +68,13 @@ config ROCKCHIP_OTP addressing and a length or through child-nodes that are generated based on the e-fuse map retrieved from the DTS.
+config SIFIVE_OTP + bool "SiFive eMemory OTP driver" + depends on MISC + help + Enable support for reading and writing the eMemory OTP on the + SiFive SoCs. + config VEXPRESS_CONFIG bool "Enable support for Arm Versatile Express config bus" depends on MISC diff --git a/drivers/misc/Makefile b/drivers/misc/Makefile index 68e0e7ad17..947bd3a647 100644 --- a/drivers/misc/Makefile +++ b/drivers/misc/Makefile @@ -59,6 +59,7 @@ obj-$(CONFIG_QFW) += qfw.o obj-$(CONFIG_ROCKCHIP_EFUSE) += rockchip-efuse.o obj-$(CONFIG_ROCKCHIP_OTP) += rockchip-otp.o obj-$(CONFIG_SANDBOX) += syscon_sandbox.o misc_sandbox.o +obj-$(CONFIG_SIFIVE_OTP) += sifive-otp.o obj-$(CONFIG_SMSC_LPC47M) += smsc_lpc47m.o obj-$(CONFIG_SMSC_SIO1007) += smsc_sio1007.o obj-$(CONFIG_STM32MP_FUSE) += stm32mp_fuse.o diff --git a/drivers/misc/sifive-otp.c b/drivers/misc/sifive-otp.c new file mode 100644 index 0000000000..92f08dde01 --- /dev/null +++ b/drivers/misc/sifive-otp.c @@ -0,0 +1,275 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * This is a driver for the eMemory EG004K32TQ028XW01 NeoFuse + * One-Time-Programmable (OTP) memory used within the SiFive FU540. + * It is documented in the FU540 manual here: + * https://www.sifive.com/documentation/chips/freedom-u540-c000-manual/ + * + * Copyright (C) 2018 Philipp Hug philipp@hug.cx + * Copyright (C) 2018 Joey Hewitt joey@joeyhewitt.com + * + * Copyright (C) 2020 SiFive, Inc + */ + +/* + * The FU540 stores 4096x32 bit (16KiB) values. + * Index 0x00-0xff are reserved for SiFive internal use. (first 1KiB) + * Right now first 1KiB is used to store only serial number. + */ + +#include <common.h> +#include <dm/device.h> +#include <dm/read.h> +#include <linux/bitops.h> +#include <linux/delay.h> +#include <linux/io.h> +#include <misc.h> + +#define BYTES_PER_FUSE 4 + +#define PA_RESET_VAL 0x00 +#define PAS_RESET_VAL 0x00 +#define PAIO_RESET_VAL 0x00 +#define PDIN_RESET_VAL 0x00 +#define PTM_RESET_VAL 0x00 + +#define PCLK_ENABLE_VAL BIT(0) +#define PCLK_DISABLE_VAL 0x00 + +#define PWE_WRITE_ENABLE BIT(0) +#define PWE_WRITE_DISABLE 0x00 + +#define PTM_FUSE_PROGRAM_VAL BIT(1) + +#define PCE_ENABLE_INPUT BIT(0) +#define PCE_DISABLE_INPUT 0x00 + +#define PPROG_ENABLE_INPUT BIT(0) +#define PPROG_DISABLE_INPUT 0x00 + +#define PTRIM_ENABLE_INPUT BIT(0) +#define PTRIM_DISABLE_INPUT 0x00 + +#define PDSTB_DEEP_STANDBY_ENABLE BIT(0) +#define PDSTB_DEEP_STANDBY_DISABLE 0x00 + +/* Tpw - Program Pulse width delay */ +#define TPW_DELAY 20 + +/* Tpwi - Program Pulse interval delay */ +#define TPWI_DELAY 5 + +/* Tasp - Program address setup delay */ +#define TASP_DELAY 1 + +/* Tcd - read data access delay */ +#define TCD_DELAY 40 + +/* Tkl - clok pulse low delay */ +#define TKL_DELAY 10 + +/* Tms - PTM mode setup delay */ +#define TMS_DELAY 1 + +struct sifive_otp_regs { + u32 pa; /* Address input */ + u32 paio; /* Program address input */ + u32 pas; /* Program redundancy cell selection input */ + u32 pce; /* OTP Macro enable input */ + u32 pclk; /* Clock input */ + u32 pdin; /* Write data input */ + u32 pdout; /* Read data output */ + u32 pdstb; /* Deep standby mode enable input (active low) */ + u32 pprog; /* Program mode enable input */ + u32 ptc; /* Test column enable input */ + u32 ptm; /* Test mode enable input */ + u32 ptm_rep;/* Repair function test mode enable input */ + u32 ptr; /* Test row enable input */ + u32 ptrim; /* Repair function enable input */ + u32 pwe; /* Write enable input (defines program cycle) */ +}; + +struct sifive_otp_platdata { + struct sifive_otp_regs __iomem *regs; + u32 total_fuses; +}; + +/* + * offset and size are assumed aligned to the size of the fuses (32-bit). + */ +static int sifive_otp_read(struct udevice *dev, int offset, + void *buf, int size) +{ + struct sifive_otp_platdata *plat = dev_get_platdata(dev); + struct sifive_otp_regs *regs = (struct sifive_otp_regs *)plat->regs; + + /* Check if offset and size are multiple of BYTES_PER_FUSE */ + if ((size % BYTES_PER_FUSE) || (offset % BYTES_PER_FUSE)) { + printf("%s: size and offset must be multiple of 4.\n", + __func__); + return -EINVAL; + } + + int fuseidx = offset / BYTES_PER_FUSE; + int fusecount = size / BYTES_PER_FUSE; + + /* check bounds */ + if (offset < 0 || size < 0) + return -EINVAL; + if (fuseidx >= plat->total_fuses) + return -EINVAL; + if ((fuseidx + fusecount) > plat->total_fuses) + return -EINVAL; + + u32 fusebuf[fusecount]; + + /* init OTP */ + writel(PDSTB_DEEP_STANDBY_ENABLE, ®s->pdstb); + writel(PTRIM_ENABLE_INPUT, ®s->ptrim); + writel(PCE_ENABLE_INPUT, ®s->pce); + + /* read all requested fuses */ + for (unsigned int i = 0; i < fusecount; i++, fuseidx++) { + writel(fuseidx, ®s->pa); + + /* cycle clock to read */ + writel(PCLK_ENABLE_VAL, ®s->pclk); + ndelay(TCD_DELAY * 1000); + writel(PCLK_DISABLE_VAL, ®s->pclk); + ndelay(TKL_DELAY * 1000); + + /* read the value */ + fusebuf[i] = readl(®s->pdout); + } + + /* shut down */ + writel(PCE_DISABLE_INPUT, ®s->pce); + writel(PTRIM_DISABLE_INPUT, ®s->ptrim); + writel(PDSTB_DEEP_STANDBY_DISABLE, ®s->pdstb); + + /* copy out */ + memcpy(buf, fusebuf, size); + + return size; +} + +/* + * Caution: + * OTP can be written only once, so use carefully. + * + * offset and size are assumed aligned to the size of the fuses (32-bit). + */ +static int sifive_otp_write(struct udevice *dev, int offset, + const void *buf, int size) +{ + struct sifive_otp_platdata *plat = dev_get_platdata(dev); + struct sifive_otp_regs *regs = (struct sifive_otp_regs *)plat->regs; + + /* Check if offset and size are multiple of BYTES_PER_FUSE */ + if ((size % BYTES_PER_FUSE) || (offset % BYTES_PER_FUSE)) { + printf("%s: size and offset must be multiple of 4.\n", + __func__); + return -EINVAL; + } + + int fuseidx = offset / BYTES_PER_FUSE; + int fusecount = size / BYTES_PER_FUSE; + u32 *write_buf = (u32 *)buf; + u32 write_data; + int i, pas, bit; + + /* check bounds */ + if (offset < 0 || size < 0) + return -EINVAL; + if (fuseidx >= plat->total_fuses) + return -EINVAL; + if ((fuseidx + fusecount) > plat->total_fuses) + return -EINVAL; + + /* init OTP */ + writel(PDSTB_DEEP_STANDBY_ENABLE, ®s->pdstb); + writel(PTRIM_ENABLE_INPUT, ®s->ptrim); + + /* reset registers */ + writel(PCLK_DISABLE_VAL, ®s->pclk); + writel(PA_RESET_VAL, ®s->pa); + writel(PAS_RESET_VAL, ®s->pas); + writel(PAIO_RESET_VAL, ®s->paio); + writel(PDIN_RESET_VAL, ®s->pdin); + writel(PWE_WRITE_DISABLE, ®s->pwe); + writel(PTM_FUSE_PROGRAM_VAL, ®s->ptm); + ndelay(TMS_DELAY * 1000); + + writel(PCE_ENABLE_INPUT, ®s->pce); + writel(PPROG_ENABLE_INPUT, ®s->pprog); + + /* write all requested fuses */ + for (i = 0; i < fusecount; i++, fuseidx++) { + writel(fuseidx, ®s->pa); + write_data = *(write_buf++); + + for (pas = 0; pas < 2; pas++) { + writel(pas, ®s->pas); + + for (bit = 0; bit < 32; bit++) { + writel(bit, ®s->paio); + writel(((write_data >> bit) & 1), + ®s->pdin); + ndelay(TASP_DELAY * 1000); + + writel(PWE_WRITE_ENABLE, ®s->pwe); + udelay(TPW_DELAY); + writel(PWE_WRITE_DISABLE, ®s->pwe); + udelay(TPWI_DELAY); + } + } + + writel(PAS_RESET_VAL, ®s->pas); + } + + /* shut down */ + writel(PWE_WRITE_DISABLE, ®s->pwe); + writel(PPROG_DISABLE_INPUT, ®s->pprog); + writel(PCE_DISABLE_INPUT, ®s->pce); + writel(PTM_RESET_VAL, ®s->ptm); + + writel(PTRIM_DISABLE_INPUT, ®s->ptrim); + writel(PDSTB_DEEP_STANDBY_DISABLE, ®s->pdstb); + + return size; +} + +static int sifive_otp_ofdata_to_platdata(struct udevice *dev) +{ + struct sifive_otp_platdata *plat = dev_get_platdata(dev); + int ret; + + plat->regs = dev_read_addr_ptr(dev); + + ret = dev_read_u32(dev, "fuse-count", &plat->total_fuses); + if (ret < 0) { + pr_err(""fuse-count" not found\n"); + return ret; + } + + return 0; +} + +static const struct misc_ops sifive_otp_ops = { + .read = sifive_otp_read, + .write = sifive_otp_write, +}; + +static const struct udevice_id sifive_otp_ids[] = { + { .compatible = "sifive,fu540-c000-otp" }, + {} +}; + +U_BOOT_DRIVER(sifive_otp) = { + .name = "sifive_otp", + .id = UCLASS_MISC, + .of_match = sifive_otp_ids, + .ofdata_to_platdata = sifive_otp_ofdata_to_platdata, + .platdata_auto_alloc_size = sizeof(struct sifive_otp_platdata), + .ops = &sifive_otp_ops, +};