hw/intc/armv7m_nvic: Implement M profile cache maintenance ops

For M profile cores, cache maintenance operations are done by
writing to special registers in the system register space.
For QEMU, cache operations are always NOPs, since we don't
implement the cache. Implementing these explicitly avoids
a spurious LOG_GUEST_ERROR when the guest uses them.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20180209165810.6668-4-peter.maydell@linaro.org

diff --git a/hw/intc/armv7m_nvic.c b/hw/intc/armv7m_nvic.c
index 06b9598..74b25ce 100644 (file)
--- a/hw/intc/armv7m_nvic.c
+++ b/hw/intc/armv7m_nvic.c
@@ -1594,6 +1594,18 @@ static void nvic_writel(NVICState *s, uint32_t offset, uint32_t value,
         }
         break;
     }
+    case 0xf50: /* ICIALLU */
+    case 0xf58: /* ICIMVAU */
+    case 0xf5c: /* DCIMVAC */
+    case 0xf60: /* DCISW */
+    case 0xf64: /* DCCMVAU */
+    case 0xf68: /* DCCMVAC */
+    case 0xf6c: /* DCCSW */
+    case 0xf70: /* DCCIMVAC */
+    case 0xf74: /* DCCISW */
+    case 0xf78: /* BPIALL */
+        /* Cache and branch predictor maintenance: for QEMU these always NOP */
+        break;
     default:
     bad_offset:
         qemu_log_mask(LOG_GUEST_ERROR,