linuxdebug/arch/riscv/errata/thead/errata.c

96 lines
2.3 KiB
C

// 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();
}