[PATCH] riscv: dts: spacemit: k3: fix IMSIC guest parameters

[Guo Ren <guoren@kernel.org>]

From: "GUO Ren (XuanTie)" <guoren@kernel.org>

The initial K3 device tree used generic/placeholder values for the
IMSIC guest configuration:

  riscv,guest-index-bits = <6>;
  riscv,num-guest-ids    = <511>;

According to the SpacemiT K3 User Manual [1] these values are
incorrect for the X100 cores:

 - Hypervisor Extension: RVH 1.0, GEILEN = 8
 - Advanced Interrupt Architecture (AIA):
    - M-mode MSI: 512
    - S-mode MSI: 512
    - VS-mode MSI: 64

Therefore:

- S-mode IMSIC (simsic) only needs guest-index-bits = 3 (to cover
  GEILEN = 8) and num-guest-ids = 63.
- M-mode IMSIC (mimsic) does not implement guest interrupt files at
  all, so the guest-related properties must be omitted.

Although the KVM AIA driver will re-detect the actual number of guest
interrupt files via hgeie and correct guest-index-bits at runtime, the
device tree should still describe the correct hardware parameters.

Update the device tree to match the silicon.

[1] https://www.spacemit.com/community/document/info?lang=en&nodepath=hardware/key_stone/k3/k3_docs/k3_usermanual/08_cpu.md

Fixes: 56f37e391a62 ("riscv: dts: spacemit: add initial support for K3 SoC")
Cc: stable@vger.kernel.org
Cc: Guodong Xu <docular.xu@gmail.com>
Cc: Yixun Lan <dlan@kernel.org>
Signed-off-by: GUO Ren (XuanTie) <guoren@kernel.org>
---
 arch/riscv/boot/dts/spacemit/k3.dtsi | 6 ++----
 1 file changed, 2 insertions(+), 4 deletions(-)

diff --git a/arch/riscv/boot/dts/spacemit/k3.dtsi b/arch/riscv/boot/dts/spacemit/k3.dtsi
index 19fc9b49668e..4120eb0c4083 100644
--- a/arch/riscv/boot/dts/spacemit/k3.dtsi
+++ b/arch/riscv/boot/dts/spacemit/k3.dtsi
@@ -1127,9 +1127,9 @@ simsic: interrupt-controller@e0400000 {
 					      <&cpu4_intc 9>, <&cpu5_intc 9>,
 					      <&cpu6_intc 9>, <&cpu7_intc 9>;
 			msi-controller;
-			riscv,guest-index-bits = <6>;
+			riscv,guest-index-bits = <3>;
 			riscv,hart-index-bits = <4>;
-			riscv,num-guest-ids = <511>;
+			riscv,num-guest-ids = <63>;
 			riscv,num-ids = <511>;
 		};
 
@@ -1168,9 +1168,7 @@ mimsic: interrupt-controller@f1000000 {
 					      <&cpu4_intc 11>, <&cpu5_intc 11>,
 					      <&cpu6_intc 11>, <&cpu7_intc 11>;
 			msi-controller;
-			riscv,guest-index-bits = <6>;
 			riscv,hart-index-bits = <4>;
-			riscv,num-guest-ids = <511>;
 			riscv,num-ids = <511>;
 			status = "reserved";
 		};
-- 
2.43.0


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