Re: [PATCH v2 2/6] target/riscv: hardwire mstatus.FS to zero when enable

qemu-riscv

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: [PATCH v2 2/6] target/riscv: hardwire mstatus.FS to zero when enable

From:	Richard Henderson
Subject:	Re: [PATCH v2 2/6] target/riscv: hardwire mstatus.FS to zero when enable zfinx
Date:	Fri, 31 Dec 2021 11:56:22 -0800
User-agent:	Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.14.0

On 12/30/21 7:23 PM, Weiwei Li wrote:

@@ -363,6 +363,10 @@ static void riscv_cpu_reset(DeviceState *dev)
      env->misa_mxl = env->misa_mxl_max;
      env->priv = PRV_M;
      env->mstatus &= ~(MSTATUS_MIE | MSTATUS_MPRV);
+    /* hardwire mstatus.FS to zero when enable zfinx */
+    if (RISCV_CPU(env_cpu(env))->cfg.ext_zfinx) {
+        env->mstatus &= ~MSTATUS_FS;
+    }


This shouldn't be necessary because it should never have been set.

-    uint64_t mstatus_mask = MSTATUS_MXR | MSTATUS_SUM | MSTATUS_FS |
+    uint64_t mstatus_mask = MSTATUS_MXR | MSTATUS_SUM|
                              MSTATUS_SPP | MSTATUS_SPIE | MSTATUS_SIE |
                              MSTATUS64_UXL | MSTATUS_VS;
+    /* hardwire mstatus.FS to zero when enable zfinx */
+    if (!RISCV_CPU(env_cpu(env))->cfg.ext_zfinx) {
+        mstatus_mask |= MSTATUS_FS;
+    }

I would think it would be more correct to have a positive test for RVF, rather than anegative test for ZFINX?

r~

[Prev in Thread]

Current Thread

[Next in Thread]

Re: [PATCH v2 5/6] target/riscv: add support for zhinx/zhinxmin, (continued)
- [PATCH v2 1/6] target/riscv: add cfg properties for zfinx, zdinx and zhinx{min}, Weiwei Li, 2021/12/30
  - Re: [PATCH v2 1/6] target/riscv: add cfg properties for zfinx, zdinx and zhinx{min}, Bin Meng, 2021/12/31
- [PATCH v2 4/6] target/riscv: add support for zdinx, Weiwei Li, 2021/12/30
  - Re: [PATCH v2 4/6] target/riscv: add support for zdinx, Richard Henderson, 2021/12/31
- [PATCH v2 3/6] target/riscv: add support for zfinx, Weiwei Li, 2021/12/30
  - Re: [PATCH v2 3/6] target/riscv: add support for zfinx, Richard Henderson, 2021/12/31
  - Re: [PATCH v2 3/6] target/riscv: add support for zfinx, Richard Henderson, 2021/12/31
- [PATCH v2 6/6] target/riscv: expose zfinx, zdinx, zhinx{min} properties, Weiwei Li, 2021/12/30
- [PATCH v2 2/6] target/riscv: hardwire mstatus.FS to zero when enable zfinx, Weiwei Li, 2021/12/30
  - Re: [PATCH v2 2/6] target/riscv: hardwire mstatus.FS to zero when enable zfinx, Richard Henderson <=

Prev by Date: [PATCH v2 2/3] target/riscv: add support for svinval extension
Next by Date: Re: [PATCH v2 3/6] target/riscv: add support for zfinx
Previous by thread: [PATCH v2 2/6] target/riscv: hardwire mstatus.FS to zero when enable zfinx
Next by thread: [PATCH v2 0/3] support subsets of virtual memory extension
Index(es):
- Date
- Thread