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-rw-r--r--arch/riscv/errata/sifive/errata.c120
1 files changed, 120 insertions, 0 deletions
diff --git a/arch/riscv/errata/sifive/errata.c b/arch/riscv/errata/sifive/errata.c
new file mode 100644
index 000000000..c24a349dd
--- /dev/null
+++ b/arch/riscv/errata/sifive/errata.c
@@ -0,0 +1,120 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (C) 2021 Sifive.
+ */
+
+#include <linux/kernel.h>
+#include <linux/memory.h>
+#include <linux/module.h>
+#include <linux/string.h>
+#include <linux/bug.h>
+#include <asm/patch.h>
+#include <asm/alternative.h>
+#include <asm/vendorid_list.h>
+#include <asm/errata_list.h>
+
+struct errata_info_t {
+ char name[ERRATA_STRING_LENGTH_MAX];
+ bool (*check_func)(unsigned long arch_id, unsigned long impid);
+};
+
+static bool errata_cip_453_check_func(unsigned long arch_id, unsigned long impid)
+{
+ /*
+ * Affected cores:
+ * Architecture ID: 0x8000000000000007
+ * Implement ID: 0x20181004 <= impid <= 0x20191105
+ */
+ if (arch_id != 0x8000000000000007 ||
+ (impid < 0x20181004 || impid > 0x20191105))
+ return false;
+ return true;
+}
+
+static bool errata_cip_1200_check_func(unsigned long arch_id, unsigned long impid)
+{
+ /*
+ * Affected cores:
+ * Architecture ID: 0x8000000000000007 or 0x1
+ * Implement ID: mimpid[23:0] <= 0x200630 and mimpid != 0x01200626
+ */
+ if (arch_id != 0x8000000000000007 && arch_id != 0x1)
+ return false;
+ if ((impid & 0xffffff) > 0x200630 || impid == 0x1200626)
+ return false;
+ return true;
+}
+
+static struct errata_info_t errata_list[ERRATA_SIFIVE_NUMBER] = {
+ {
+ .name = "cip-453",
+ .check_func = errata_cip_453_check_func
+ },
+ {
+ .name = "cip-1200",
+ .check_func = errata_cip_1200_check_func
+ },
+};
+
+static u32 __init_or_module 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_or_module 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_or_module sifive_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;
+ u32 cpu_apply_errata = 0;
+ u32 tmp;
+
+ if (stage == RISCV_ALTERNATIVES_EARLY_BOOT)
+ return;
+
+ cpu_req_errata = sifive_errata_probe(archid, impid);
+
+ 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) {
+ mutex_lock(&text_mutex);
+ patch_text_nosync(alt->old_ptr, alt->alt_ptr, alt->alt_len);
+ mutex_unlock(&text_mutex);
+ cpu_apply_errata |= tmp;
+ }
+ }
+ if (stage != RISCV_ALTERNATIVES_MODULE &&
+ cpu_apply_errata != cpu_req_errata)
+ warn_miss_errata(cpu_req_errata - cpu_apply_errata);
+}