diff options
Diffstat (limited to '')
-rw-r--r-- | arch/riscv/errata/thead/errata.c | 95 |
1 files changed, 95 insertions, 0 deletions
diff --git a/arch/riscv/errata/thead/errata.c b/arch/riscv/errata/thead/errata.c new file mode 100644 index 000000000..32a34ed73 --- /dev/null +++ b/arch/riscv/errata/thead/errata.c @@ -0,0 +1,95 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright (C) 2021 Heiko Stuebner <heiko@sntech.de> + */ + +#include <linux/bug.h> +#include <linux/kernel.h> +#include <linux/memory.h> +#include <linux/module.h> +#include <linux/string.h> +#include <linux/uaccess.h> +#include <asm/alternative.h> +#include <asm/cacheflush.h> +#include <asm/errata_list.h> +#include <asm/patch.h> +#include <asm/vendorid_list.h> + +static bool errata_probe_pbmt(unsigned int stage, + unsigned long arch_id, unsigned long impid) +{ + if (!IS_ENABLED(CONFIG_ERRATA_THEAD_PBMT)) + return false; + + if (arch_id != 0 || impid != 0) + return false; + + if (stage == RISCV_ALTERNATIVES_EARLY_BOOT || + stage == RISCV_ALTERNATIVES_MODULE) + return true; + + return false; +} + +static bool errata_probe_cmo(unsigned int stage, + unsigned long arch_id, unsigned long impid) +{ + if (!IS_ENABLED(CONFIG_ERRATA_THEAD_CMO)) + return false; + + if (arch_id != 0 || impid != 0) + return false; + + if (stage == RISCV_ALTERNATIVES_EARLY_BOOT) + return false; + + riscv_cbom_block_size = L1_CACHE_BYTES; + riscv_noncoherent_supported(); + return true; +} + +static u32 thead_errata_probe(unsigned int stage, + unsigned long archid, unsigned long impid) +{ + u32 cpu_req_errata = 0; + + if (errata_probe_pbmt(stage, archid, impid)) + cpu_req_errata |= BIT(ERRATA_THEAD_PBMT); + + if (errata_probe_cmo(stage, archid, impid)) + cpu_req_errata |= BIT(ERRATA_THEAD_CMO); + + return cpu_req_errata; +} + +void __init_or_module thead_errata_patch_func(struct alt_entry *begin, struct alt_entry *end, + unsigned long archid, unsigned long impid, + unsigned int stage) +{ + struct alt_entry *alt; + u32 cpu_req_errata = thead_errata_probe(stage, archid, impid); + u32 tmp; + + for (alt = begin; alt < end; alt++) { + if (alt->vendor_id != THEAD_VENDOR_ID) + continue; + if (alt->errata_id >= ERRATA_THEAD_NUMBER) + continue; + + tmp = (1U << alt->errata_id); + if (cpu_req_errata & tmp) { + /* On vm-alternatives, the mmu isn't running yet */ + if (stage == RISCV_ALTERNATIVES_EARLY_BOOT) { + memcpy((void *)__pa_symbol(alt->old_ptr), + (void *)__pa_symbol(alt->alt_ptr), alt->alt_len); + } else { + mutex_lock(&text_mutex); + patch_text_nosync(alt->old_ptr, alt->alt_ptr, alt->alt_len); + mutex_unlock(&text_mutex); + } + } + } + + if (stage == RISCV_ALTERNATIVES_EARLY_BOOT) + local_flush_icache_all(); +} |