hw/intc: sifive_plic: Cleanup the write function

Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
Message-Id: <20220105213937.1113508-3-alistair.francis@opensource.wdc.com>

1 files changed, 27 insertions, 49 deletions

diff --git a/hw/intc/sifive_plic.c b/hw/intc/sifive_plic.c
index a9f7a1b..698492c 100644
--- a/hw/intc/sifive_plic.c
+++ b/hw/intc/sifive_plic.c
@@ -33,6 +33,11 @@
 
 #define RISCV_DEBUG_PLIC 0
 
+static bool addr_between(uint32_t addr, uint32_t base, uint32_t num)
+{
+    return addr >= base && addr - base < num;
+}
+
 static PLICMode char_to_mode(char c)
 {
     switch (c) {
@@ -269,80 +274,53 @@ static void sifive_plic_write(void *opaque, hwaddr addr, uint64_t value,
 {
     SiFivePLICState *plic = opaque;
 
-    /* writes must be 4 byte words */
-    if ((addr & 0x3) != 0) {
-        goto err;
-    }
-
-    if (addr >= plic->priority_base && /* 4 bytes per source */
-        addr < plic->priority_base + (plic->num_sources << 2))
-    {
+    if (addr_between(addr, plic->priority_base, plic->num_sources << 2)) {
         uint32_t irq = ((addr - plic->priority_base) >> 2) + 1;
+
         plic->source_priority[irq] = value & 7;
-        if (RISCV_DEBUG_PLIC) {
-            qemu_log("plic: write priority: irq=%d priority=%d\n",
-                irq, plic->source_priority[irq]);
-        }
         sifive_plic_update(plic);
-        return;
-    } else if (addr >= plic->pending_base && /* 1 bit per source */
-               addr < plic->pending_base + (plic->num_sources >> 3))
-    {
+    } else if (addr_between(addr, plic->pending_base,
+                            plic->num_sources >> 3)) {
         qemu_log_mask(LOG_GUEST_ERROR,
                       "%s: invalid pending write: 0x%" HWADDR_PRIx "",
                       __func__, addr);
-        return;
-    } else if (addr >= plic->enable_base && /* 1 bit per source */
-        addr < plic->enable_base + plic->num_addrs * plic->enable_stride)
-    {
+    } else if (addr_between(addr, plic->enable_base,
+                            plic->num_addrs * plic->enable_stride)) {
         uint32_t addrid = (addr - plic->enable_base) / plic->enable_stride;
         uint32_t wordid = (addr & (plic->enable_stride - 1)) >> 2;
+
         if (wordid < plic->bitfield_words) {
             plic->enable[addrid * plic->bitfield_words + wordid] = value;
-            if (RISCV_DEBUG_PLIC) {
-                qemu_log("plic: write enable: hart%d-%c word=%d value=%x\n",
-                    plic->addr_config[addrid].hartid,
-                    mode_to_char(plic->addr_config[addrid].mode), wordid,
-                    plic->enable[addrid * plic->bitfield_words + wordid]);
-            }
-            return;
+        } else {
+            qemu_log_mask(LOG_GUEST_ERROR,
+                          "%s: Invalid enable write 0x%" HWADDR_PRIx "\n",
+                          __func__, addr);
         }
-    } else if (addr >= plic->context_base && /* 4 bytes per reg */
-        addr < plic->context_base + plic->num_addrs * plic->context_stride)
-    {
+    } else if (addr_between(addr, plic->context_base,
+                            plic->num_addrs * plic->context_stride)) {
         uint32_t addrid = (addr - plic->context_base) / plic->context_stride;
         uint32_t contextid = (addr & (plic->context_stride - 1));
+
         if (contextid == 0) {
-            if (RISCV_DEBUG_PLIC) {
-                qemu_log("plic: write priority: hart%d-%c priority=%x\n",
-                    plic->addr_config[addrid].hartid,
-                    mode_to_char(plic->addr_config[addrid].mode),
-                    plic->target_priority[addrid]);
-            }
             if (value <= plic->num_priorities) {
                 plic->target_priority[addrid] = value;
                 sifive_plic_update(plic);
             }
-            return;
         } else if (contextid == 4) {
-            if (RISCV_DEBUG_PLIC) {
-                qemu_log("plic: write claim: hart%d-%c irq=%x\n",
-                    plic->addr_config[addrid].hartid,
-                    mode_to_char(plic->addr_config[addrid].mode),
-                    (uint32_t)value);
-            }
             if (value < plic->num_sources) {
                 sifive_plic_set_claimed(plic, value, false);
                 sifive_plic_update(plic);
             }
-            return;
+        } else {
+            qemu_log_mask(LOG_GUEST_ERROR,
+                          "%s: Invalid context write 0x%" HWADDR_PRIx "\n",
+                          __func__, addr);
         }
+    } else {
+        qemu_log_mask(LOG_GUEST_ERROR,
+                      "%s: Invalid register write 0x%" HWADDR_PRIx "\n",
+                      __func__, addr);
     }
-
-err:
-    qemu_log_mask(LOG_GUEST_ERROR,
-                  "%s: Invalid register write 0x%" HWADDR_PRIx "\n",
-                  __func__, addr);
 }
 
 static const MemoryRegionOps sifive_plic_ops = {