From 1a0e5dbd3723e1194cc549def69fe7b557d4c72b Mon Sep 17 00:00:00 2001 From: Vincent Chen Date: Mon, 22 Mar 2021 22:26:04 +0800 Subject: riscv: sifive: Add SiFive alternative ports Add required ports of the Alternative scheme for SiFive. Signed-off-by: Vincent Chen Reviewed-by: Anup Patel Signed-off-by: Palmer Dabbelt --- arch/riscv/Kconfig.erratas | 10 ++++++ arch/riscv/Kconfig.socs | 1 + arch/riscv/errata/Makefile | 1 + arch/riscv/errata/alternative.c | 5 +++ arch/riscv/errata/sifive/Makefile | 1 + arch/riscv/errata/sifive/errata.c | 68 ++++++++++++++++++++++++++++++++++++ arch/riscv/include/asm/alternative.h | 3 ++ 7 files changed, 89 insertions(+) create mode 100644 arch/riscv/errata/sifive/Makefile create mode 100644 arch/riscv/errata/sifive/errata.c (limited to 'arch/riscv') diff --git a/arch/riscv/Kconfig.erratas b/arch/riscv/Kconfig.erratas index 4d0bafc536df..302e7467f302 100644 --- a/arch/riscv/Kconfig.erratas +++ b/arch/riscv/Kconfig.erratas @@ -9,4 +9,14 @@ config RISCV_ERRATA_ALTERNATIVE code patching is performed once in the boot stages. It means that the overhead from this mechanism is just taken once. +config ERRATA_SIFIVE + bool "SiFive errata" + depends on RISCV_ERRATA_ALTERNATIVE + help + All SiFive errata Kconfig depend on this Kconfig. Disabling + this Kconfig will disable all SiFive errata. Please say "Y" + here if your platform uses SiFive CPU cores. + + Otherwise, please say "N" here to avoid unnecessary overhead. + endmenu diff --git a/arch/riscv/Kconfig.socs b/arch/riscv/Kconfig.socs index 7efcece8896c..b9eda857fc87 100644 --- a/arch/riscv/Kconfig.socs +++ b/arch/riscv/Kconfig.socs @@ -7,6 +7,7 @@ config SOC_SIFIVE select CLK_SIFIVE select CLK_SIFIVE_PRCI select SIFIVE_PLIC + select ERRATA_SIFIVE help This enables support for SiFive SoC platform hardware. diff --git a/arch/riscv/errata/Makefile b/arch/riscv/errata/Makefile index 43e6d5424367..b8f8740a3e44 100644 --- a/arch/riscv/errata/Makefile +++ b/arch/riscv/errata/Makefile @@ -1 +1,2 @@ obj-y += alternative.o +obj-$(CONFIG_ERRATA_SIFIVE) += sifive/ diff --git a/arch/riscv/errata/alternative.c b/arch/riscv/errata/alternative.c index 8efa60ad69b7..3b15885db70b 100644 --- a/arch/riscv/errata/alternative.c +++ b/arch/riscv/errata/alternative.c @@ -42,6 +42,11 @@ static void __init init_alternative(void) riscv_fill_cpu_mfr_info(); switch (cpu_mfr_info.vendor_id) { +#ifdef CONFIG_ERRATA_SIFIVE + case SIFIVE_VENDOR_ID: + vendor_patch_func = sifive_errata_patch_func; + break; +#endif default: vendor_patch_func = NULL; } diff --git a/arch/riscv/errata/sifive/Makefile b/arch/riscv/errata/sifive/Makefile new file mode 100644 index 000000000000..2d644e19caef --- /dev/null +++ b/arch/riscv/errata/sifive/Makefile @@ -0,0 +1 @@ +obj-y += errata.o diff --git a/arch/riscv/errata/sifive/errata.c b/arch/riscv/errata/sifive/errata.c new file mode 100644 index 000000000000..826cd391fc55 --- /dev/null +++ b/arch/riscv/errata/sifive/errata.c @@ -0,0 +1,68 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright (C) 2021 Sifive. + */ + +#include +#include +#include +#include +#include +#include +#include + +struct errata_info_t { + char name[ERRATA_STRING_LENGTH_MAX]; + bool (*check_func)(unsigned long arch_id, unsigned long impid); +}; + +static u32 __init sifive_errata_probe(unsigned long archid, unsigned long impid) +{ + int idx; + u32 cpu_req_errata = 0; + + for (idx = 0; idx < ERRATA_SIFIVE_NUMBER; idx++) + if (errata_list[idx].check_func(archid, impid)) + cpu_req_errata |= (1U << idx); + + return cpu_req_errata; +} + +static void __init warn_miss_errata(u32 miss_errata) +{ + int i; + + pr_warn("----------------------------------------------------------------\n"); + pr_warn("WARNING: Missing the following errata may cause potential issues\n"); + for (i = 0; i < ERRATA_SIFIVE_NUMBER; i++) + if (miss_errata & 0x1 << i) + pr_warn("\tSiFive Errata[%d]:%s\n", i, errata_list[i].name); + pr_warn("Please enable the corresponding Kconfig to apply them\n"); + pr_warn("----------------------------------------------------------------\n"); +} + +void __init sifive_errata_patch_func(struct alt_entry *begin, struct alt_entry *end, + unsigned long archid, unsigned long impid) +{ + struct alt_entry *alt; + u32 cpu_req_errata = sifive_errata_probe(archid, impid); + u32 cpu_apply_errata = 0; + u32 tmp; + + for (alt = begin; alt < end; alt++) { + if (alt->vendor_id != SIFIVE_VENDOR_ID) + continue; + if (alt->errata_id >= ERRATA_SIFIVE_NUMBER) { + WARN(1, "This errata id:%d is not in kernel errata list", alt->errata_id); + continue; + } + + tmp = (1U << alt->errata_id); + if (cpu_req_errata & tmp) { + patch_text_nosync(alt->old_ptr, alt->alt_ptr, alt->alt_len); + cpu_apply_errata |= tmp; + } + } + if (cpu_apply_errata != cpu_req_errata) + warn_miss_errata(cpu_req_errata - cpu_apply_errata); +} diff --git a/arch/riscv/include/asm/alternative.h b/arch/riscv/include/asm/alternative.h index 430bc4fea133..e625d3cafbed 100644 --- a/arch/riscv/include/asm/alternative.h +++ b/arch/riscv/include/asm/alternative.h @@ -32,5 +32,8 @@ struct errata_checkfunc_id { bool (*func)(struct alt_entry *alt); }; +void sifive_errata_patch_func(struct alt_entry *begin, struct alt_entry *end, + unsigned long archid, unsigned long impid); + #endif #endif -- cgit v1.2.3