summary refs log tree commit diff stats
path: root/hw/intc
diff options
context:
space:
mode:
authorPeter Maydell <peter.maydell@linaro.org>2020-11-19 21:56:14 +0000
committerPeter Maydell <peter.maydell@linaro.org>2020-12-10 11:44:56 +0000
commit46f4976f22a4549322307b34272e053d38653243 (patch)
treebd3e19198ef044a4a60a3995512f98a3856d58c3 /hw/intc
parent194cde6df20d139dbb952ef6c8c011f2126d03a4 (diff)
downloadfocaccia-qemu-46f4976f22a4549322307b34272e053d38653243.tar.gz
focaccia-qemu-46f4976f22a4549322307b34272e053d38653243.zip
target/arm: Implement M-profile "minimal RAS implementation"
For v8.1M the architecture mandates that CPUs must provide at
least the "minimal RAS implementation" from the Reliability,
Availability and Serviceability extension. This consists of:
 * an ESB instruction which is a NOP
   -- since it is in the HINT space we need only add a comment
 * an RFSR register which will RAZ/WI
 * a RAZ/WI AIRCR.IESB bit
   -- the code which handles writes to AIRCR does not allow setting
      of RES0 bits, so we already treat this as RAZ/WI; add a comment
      noting that this is deliberate
 * minimal implementation of the RAS register block at 0xe0005000
   -- this will be in a subsequent commit
 * setting the ID_PFR0.RAS field to 0b0010
   -- we will do this when we add the Cortex-M55 CPU model

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20201119215617.29887-26-peter.maydell@linaro.org
Diffstat (limited to 'hw/intc')
-rw-r--r--hw/intc/armv7m_nvic.c13
1 files changed, 13 insertions, 0 deletions
diff --git a/hw/intc/armv7m_nvic.c b/hw/intc/armv7m_nvic.c
index cf233c0561..01e331ab1e 100644
--- a/hw/intc/armv7m_nvic.c
+++ b/hw/intc/armv7m_nvic.c
@@ -1483,6 +1483,12 @@ static uint32_t nvic_readl(NVICState *s, uint32_t offset, MemTxAttrs attrs)
             return 0;
         }
         return cpu->env.v7m.sfar;
+    case 0xf04: /* RFSR */
+        if (!cpu_isar_feature(aa32_ras, cpu)) {
+            goto bad_offset;
+        }
+        /* We provide minimal-RAS only: RFSR is RAZ/WI */
+        return 0;
     case 0xf34: /* FPCCR */
         if (!cpu_isar_feature(aa32_vfp_simd, cpu)) {
             return 0;
@@ -1611,6 +1617,7 @@ static void nvic_writel(NVICState *s, uint32_t offset, uint32_t value,
                               R_V7M_AIRCR_PRIGROUP_SHIFT,
                               R_V7M_AIRCR_PRIGROUP_LENGTH);
             }
+            /* AIRCR.IESB is RAZ/WI because we implement only minimal RAS */
             if (attrs.secure) {
                 /* These bits are only writable by secure */
                 cpu->env.v7m.aircr = value &
@@ -2026,6 +2033,12 @@ static void nvic_writel(NVICState *s, uint32_t offset, uint32_t value,
         }
         break;
     }
+    case 0xf04: /* RFSR */
+        if (!cpu_isar_feature(aa32_ras, cpu)) {
+            goto bad_offset;
+        }
+        /* We provide minimal-RAS only: RFSR is RAZ/WI */
+        break;
     case 0xf34: /* FPCCR */
         if (cpu_isar_feature(aa32_vfp_simd, cpu)) {
             /* Not all bits here are banked. */