[PATCH for-8.1 v3 18/26] target/riscv: error out on priv failure for RVH

From: Daniel Henrique Barboza <dbarboza@ventanamicro.com>
To: qemu-devel@nongnu.org
Cc: qemu-riscv@nongnu.org, alistair.francis@wdc.com,
	bmeng@tinylab.org, liweiwei@iscas.ac.cn,
	zhiwei_liu@linux.alibaba.com, palmer@rivosinc.com,
	Daniel Henrique Barboza <dbarboza@ventanamicro.com>
Subject: [PATCH for-8.1 v3 18/26] target/riscv: error out on priv failure for RVH
Date: Sat, 18 Mar 2023 17:04:28 -0300	[thread overview]
Message-ID: <20230318200436.299464-19-dbarboza@ventanamicro.com> (raw)
In-Reply-To: <20230318200436.299464-1-dbarboza@ventanamicro.com>

riscv_cpu_disable_priv_spec_isa_exts(), at the end of
riscv_cpu_validate_set_extensions(), will disable cpu->cfg.ext_h and
cpu->cfg.ext_v if priv_ver check fails.

This check can be done in riscv_cpu_validate_misa_ext(). The difference
here is that we're not silently disable it: we'll error out. Silently
disabling a MISA extension after all the validation is completed can can
cause inconsistencies that we don't have to deal with. Verify ealier and
fail faster.

Note that we're ignoring RVV priv_ver validation since its minimal priv
is also the minimal value we support. RVH will error out if enabled
under priv_ver under 1_12_0.

Signed-off-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>
---
 target/riscv/cpu.c | 14 ++++++++++++++
 1 file changed, 14 insertions(+)

diff --git a/target/riscv/cpu.c b/target/riscv/cpu.c
index 1116686cd1..d8f2eca6ca 100644
--- a/target/riscv/cpu.c
+++ b/target/riscv/cpu.c
@@ -1064,6 +1064,20 @@ static void riscv_cpu_validate_misa_ext(RISCVCPU *cpu, Error **errp)
         return;
     }
 
+    /*
+     * Check for priv spec version. RVH is 1_12_0, RVV is 1_10_0.
+     * We don't support anything under 1_10_0 so skip checking
+     * priv for RVV.
+     *
+     * We're hardcoding it here to avoid looping into the
+     * 50+ entries of isa_edata_arr[] just to check the RVH
+     * entry.
+     */
+    if (cpu->cfg.ext_h && env->priv_ver < PRIV_VERSION_1_12_0) {
+        error_setg(errp, "H extension requires priv spec 1.12.0");
+        return;
+    }
+
     if (cpu->cfg.ext_v) {
         riscv_cpu_validate_v(env, &cpu->cfg, &local_err);
         if (local_err != NULL) {
-- 
2.39.2


