From 111738090c6cdf2d852717b3ad15b65e2085d237 Mon Sep 17 00:00:00 2001
From: Andrew Waterman <andrew@sifive.com>
Date: Thu, 27 Nov 2025 16:51:21 +0530
Subject: [PATCH] lib: sbi: Flush TLBs upon FWFT ADUE change

A clarification has been added to the RISC-V privileged specification
regarding synchronization requirements when xenvcfg.ADUE changes.
(Refer, the following commit in the RISC-V Privileged ISA spec
https://github.com/riscv/riscv-isa-manual/commit/4e540263db8ae3a27d132a1752cc0fad222facd8)

As-per these requirements, the SBI FWFT ADUE implementation must
flush TLBs upon changes in ADUE state on a hart.

Signed-off-by: Andrew Waterman <andrew@sifive.com>
Signed-off-by: Anup Patel <apatel@ventanamicro.com>
Link: https://lore.kernel.org/r/20251127112121.334023-3-apatel@ventanamicro.com
Signed-off-by: Anup Patel <anup@brainfault.org>
---
 lib/sbi/sbi_fwft.c | 13 ++++++++++++-
 1 file changed, 12 insertions(+), 1 deletion(-)

diff --git a/lib/sbi/sbi_fwft.c b/lib/sbi/sbi_fwft.c
index a2aefb9a..373140b7 100644
--- a/lib/sbi/sbi_fwft.c
+++ b/lib/sbi/sbi_fwft.c
@@ -13,8 +13,10 @@
 #include <sbi/sbi_error.h>
 #include <sbi/sbi_hart.h>
 #include <sbi/sbi_heap.h>
+#include <sbi/sbi_hfence.h>
 #include <sbi/sbi_scratch.h>
 #include <sbi/sbi_string.h>
+#include <sbi/sbi_tlb.h>
 #include <sbi/sbi_types.h>
 
 #include <sbi/riscv_asm.h>
@@ -167,7 +169,16 @@ static int fwft_adue_supported(struct fwft_config *conf)
 
 static int fwft_set_adue(struct fwft_config *conf, unsigned long value)
 {
-	return fwft_menvcfg_set_bit(value, ENVCFG_ADUE_SHIFT);
+	int res = fwft_menvcfg_set_bit(value, ENVCFG_ADUE_SHIFT);
+
+	if (res == SBI_OK) {
+		__sbi_sfence_vma_all();
+
+		if (misa_extension('H'))
+			__sbi_hfence_gvma_all();
+	}
+
+	return res;
 }
 
 static int fwft_get_adue(struct fwft_config *conf, unsigned long *value)