[PATCH 2/2] target/riscv: Move Guest irqs out of the core local irqs range.

[Rajnesh Kanwal]

Qemu maps IRQs 0:15 for core interrupts and 16 onward for
guest interrupts which are later translated to hgiep in
`riscv_cpu_set_irq()` function.

With virtual IRQ support added, software now can fully
use the whole local interrupt range without any actual
hardware attached.

This change moves the guest interrupt range after the
core local interrupt range to avoid clash.

Fixes: 1697837ed9 ("target/riscv: Add M-mode virtual
interrupt and IRQ filtering support.")
Fixes: 40336d5b1d ("target/riscv: Add HS-mode virtual
interrupt and IRQ filtering support.")

Signed-off-by: Rajnesh Kanwal <rkanwal@rivosinc.com>
---
 target/riscv/cpu_bits.h | 3 ++-
 target/riscv/csr.c      | 7 ++++++-
 2 files changed, 8 insertions(+), 2 deletions(-)

diff --git a/target/riscv/cpu_bits.h b/target/riscv/cpu_bits.h
index 13ce2218d1..33f28bb115 100644
--- a/target/riscv/cpu_bits.h
+++ b/target/riscv/cpu_bits.h
@@ -664,7 +664,8 @@ typedef enum RISCVException {
 #define IRQ_M_EXT                          11
 #define IRQ_S_GEXT                         12
 #define IRQ_PMU_OVF                        13
-#define IRQ_LOCAL_MAX                      16
+#define IRQ_LOCAL_MAX                      64
+/* -1 is due to bit zero of hgeip and hgeie being ROZ. */
 #define IRQ_LOCAL_GUEST_MAX                (TARGET_LONG_BITS - 1)
 
 /* mip masks */
diff --git a/target/riscv/csr.c b/target/riscv/csr.c
index c9d685dcc5..78f42fcae5 100644
--- a/target/riscv/csr.c
+++ b/target/riscv/csr.c
@@ -1141,7 +1141,12 @@ static RISCVException write_stimecmph(CPURISCVState 
*env, int csrno,
 
 #define VSTOPI_NUM_SRCS 5
 
-#define LOCAL_INTERRUPTS (~0x1FFF)
+/* All core local interrupts except the fixed ones 0:12. This macro is for 
virtual
+ * interrupts logic so please don't change this to avoid messing up the whole 
support,
+ * For reference see AIA spec: `5.3 Interrupt filtering and virtual interrupts 
for
+ * supervisor level` and `6.3.2 Virtual interrupts for VS level`.
+ */
+#define LOCAL_INTERRUPTS   (~0x1FFFULL)
 
 static const uint64_t delegable_ints =
     S_MODE_INTERRUPTS | VS_MODE_INTERRUPTS | MIP_LCOFIP;
-- 
2.34.1