diff options
Diffstat (limited to 'arch/riscv/errata/thead/errata.c')
| -rw-r--r-- | arch/riscv/errata/thead/errata.c | 187 |
1 files changed, 187 insertions, 0 deletions
diff --git a/arch/riscv/errata/thead/errata.c b/arch/riscv/errata/thead/errata.c new file mode 100644 index 000000000000..b1c410bbc1ae --- /dev/null +++ b/arch/riscv/errata/thead/errata.c @@ -0,0 +1,187 @@ +// 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/cpufeature.h> +#include <asm/dma-noncoherent.h> +#include <asm/errata_list.h> +#include <asm/hwprobe.h> +#include <asm/io.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; +} + +/* + * th.dcache.ipa rs1 (invalidate, physical address) + * | 31 - 25 | 24 - 20 | 19 - 15 | 14 - 12 | 11 - 7 | 6 - 0 | + * 0000001 01010 rs1 000 00000 0001011 + * th.dcache.iva rs1 (invalidate, virtual address) + * 0000001 00110 rs1 000 00000 0001011 + * + * th.dcache.cpa rs1 (clean, physical address) + * | 31 - 25 | 24 - 20 | 19 - 15 | 14 - 12 | 11 - 7 | 6 - 0 | + * 0000001 01001 rs1 000 00000 0001011 + * th.dcache.cva rs1 (clean, virtual address) + * 0000001 00101 rs1 000 00000 0001011 + * + * th.dcache.cipa rs1 (clean then invalidate, physical address) + * | 31 - 25 | 24 - 20 | 19 - 15 | 14 - 12 | 11 - 7 | 6 - 0 | + * 0000001 01011 rs1 000 00000 0001011 + * th.dcache.civa rs1 (clean then invalidate, virtual address) + * 0000001 00111 rs1 000 00000 0001011 + * + * th.sync.s (make sure all cache operations finished) + * | 31 - 25 | 24 - 20 | 19 - 15 | 14 - 12 | 11 - 7 | 6 - 0 | + * 0000000 11001 00000 000 00000 0001011 + */ +#define THEAD_INVAL_A0 ".long 0x02a5000b" +#define THEAD_CLEAN_A0 ".long 0x0295000b" +#define THEAD_FLUSH_A0 ".long 0x02b5000b" +#define THEAD_SYNC_S ".long 0x0190000b" + +#define THEAD_CMO_OP(_op, _start, _size, _cachesize) \ +asm volatile("mv a0, %1\n\t" \ + "j 2f\n\t" \ + "3:\n\t" \ + THEAD_##_op##_A0 "\n\t" \ + "add a0, a0, %0\n\t" \ + "2:\n\t" \ + "bltu a0, %2, 3b\n\t" \ + THEAD_SYNC_S \ + : : "r"(_cachesize), \ + "r"((unsigned long)(_start) & ~((_cachesize) - 1UL)), \ + "r"((unsigned long)(_start) + (_size)) \ + : "a0") + +static void thead_errata_cache_inv(phys_addr_t paddr, size_t size) +{ + THEAD_CMO_OP(INVAL, paddr, size, riscv_cbom_block_size); +} + +static void thead_errata_cache_wback(phys_addr_t paddr, size_t size) +{ + THEAD_CMO_OP(CLEAN, paddr, size, riscv_cbom_block_size); +} + +static void thead_errata_cache_wback_inv(phys_addr_t paddr, size_t size) +{ + THEAD_CMO_OP(FLUSH, paddr, size, riscv_cbom_block_size); +} + +static const struct riscv_nonstd_cache_ops thead_errata_cmo_ops = { + .wback = &thead_errata_cache_wback, + .inv = &thead_errata_cache_inv, + .wback_inv = &thead_errata_cache_wback_inv, +}; + +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; + + if (stage == RISCV_ALTERNATIVES_BOOT) { + riscv_cbom_block_size = L1_CACHE_BYTES; + riscv_noncoherent_supported(); + riscv_noncoherent_register_cache_ops(&thead_errata_cmo_ops); + } + + return true; +} + +static bool errata_probe_pmu(unsigned int stage, + unsigned long arch_id, unsigned long impid) +{ + if (!IS_ENABLED(CONFIG_ERRATA_THEAD_PMU)) + return false; + + /* target-c9xx cores report arch_id and impid as 0 */ + if (arch_id != 0 || impid != 0) + return false; + + if (stage == RISCV_ALTERNATIVES_EARLY_BOOT) + return false; + + 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); + + errata_probe_cmo(stage, archid, impid); + + if (errata_probe_pmu(stage, archid, impid)) + cpu_req_errata |= BIT(ERRATA_THEAD_PMU); + + return cpu_req_errata; +} + +void 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; + void *oldptr, *altptr; + + for (alt = begin; alt < end; alt++) { + if (alt->vendor_id != THEAD_VENDOR_ID) + continue; + if (alt->patch_id >= ERRATA_THEAD_NUMBER) + continue; + + tmp = (1U << alt->patch_id); + if (cpu_req_errata & tmp) { + oldptr = ALT_OLD_PTR(alt); + altptr = ALT_ALT_PTR(alt); + + /* On vm-alternatives, the mmu isn't running yet */ + if (stage == RISCV_ALTERNATIVES_EARLY_BOOT) { + memcpy(oldptr, altptr, alt->alt_len); + } else { + mutex_lock(&text_mutex); + patch_text_nosync(oldptr, altptr, alt->alt_len); + mutex_unlock(&text_mutex); + } + } + } + + if (stage == RISCV_ALTERNATIVES_EARLY_BOOT) + local_flush_icache_all(); +} |