diff options
Diffstat (limited to 'src/soc/sifive/fu540')
| -rw-r--r-- | src/soc/sifive/fu540/Makefile.inc | 2 | ||||
| -rw-r--r-- | src/soc/sifive/fu540/include/soc/otp.h | 22 | ||||
| -rw-r--r-- | src/soc/sifive/fu540/otp.c | 105 |
3 files changed, 129 insertions, 0 deletions
diff --git a/src/soc/sifive/fu540/Makefile.inc b/src/soc/sifive/fu540/Makefile.inc index 677731a8af..12b814a6f7 100644 --- a/src/soc/sifive/fu540/Makefile.inc +++ b/src/soc/sifive/fu540/Makefile.inc @@ -21,11 +21,13 @@ bootblock-y += bootblock.c romstage-y += uart.c romstage-y += media.c romstage-y += sdram.c +romstage-y += otp.c ramstage-y += uart.c ramstage-y += media.c ramstage-y += sdram.c ramstage-y += cbmem.c +ramstage-y += otp.c CPPFLAGS_common += -Isrc/soc/sifive/fu540/include diff --git a/src/soc/sifive/fu540/include/soc/otp.h b/src/soc/sifive/fu540/include/soc/otp.h new file mode 100644 index 0000000000..a5b4ca8792 --- /dev/null +++ b/src/soc/sifive/fu540/include/soc/otp.h @@ -0,0 +1,22 @@ +/* + * This file is part of the coreboot project. + * + * Copyright 2018 Philipp Hug <philipp@hug.cx> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; version 2 of the License. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + */ + +#ifndef __SOC_SIFIVE_HIFIVE_U_OTP_H__ +#define __SOC_SIFIVE_HIFIVE_U_OTP_H__ + +u32 otp_read_word(u16 idx); +u32 otp_read_serial(void); + +#endif /* __SOC_SIFIVE_HIFIFE_U_OTP_H__ */ diff --git a/src/soc/sifive/fu540/otp.c b/src/soc/sifive/fu540/otp.c new file mode 100644 index 0000000000..e6900fe1c1 --- /dev/null +++ b/src/soc/sifive/fu540/otp.c @@ -0,0 +1,105 @@ +/* + * This file is part of the coreboot project. + * + * Copyright (C) 2018 Philipp Hug <philipp@hug.cx> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; version 2 of the License. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + */ + +#include <stddef.h> +#include <delay.h> +#include <arch/barrier.h> +#include <arch/io.h> +#include <console/console.h> +#include <console/uart.h> +#include <soc/addressmap.h> +#include <soc/otp.h> + +/* + * 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/ + */ + +typedef struct sifive_otp_registers { + 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) */ +} __packed; + +/* + * Read a 32 bit value addressed by its index from the OTP. + * The FU540 stores 4096x32 bit (16KiB) values. + * Index 0x00-0xff are reserved for SiFive internal use. (first 1KiB) + */ + +u32 otp_read_word(u16 idx) +{ + u32 w; + + if (idx >= 0x1000) + die("otp: idx out of bounds"); + + struct sifive_otp_registers *regs = (void *)(FU540_OTP); + + // wake up from stand-by + write32(®s->pdstb, 0x01); + + // enable repair function + write32(®s->ptrim, 0x01); + + // enable input + write32(®s->pce, 0x01); + + // address to read + write32(®s->pa, idx); + + // cycle clock to read + write32(®s->pclk, 0x01); + mdelay(1); + + write32(®s->pclk, 0x00); + mdelay(1); + + w = read32(®s->pdout); + + // shut down + write32(®s->pce, 0x00); + write32(®s->ptrim, 0x00); + write32(®s->pdstb, 0x00); + + return w; +} + +u32 otp_read_serial(void) +{ + u32 serial = 0; + u32 serial_n = 0; + for (int i = 0xfe; i > 0; i -= 2) { + serial = otp_read_word(i); + serial_n = otp_read_word(i+1); + if (serial == ~serial_n) + break; + } + return serial; +} |