ppc/xive2: Update NVP save/restore for group attributes

If the 'H' attribute is set on the NVP structure, the hardware
automatically saves and restores some attributes from the TIMA in the
NVP structure.

The group-specific attributes LSMFB, LGS and T have an extra flag to
individually control what is saved/restored.

Signed-off-by: Frederic Barrat <fbarrat@linux.ibm.com>
Signed-off-by: Michael Kowal <kowal@linux.ibm.com>
Reviewed-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>

2 files changed, 25 insertions, 8 deletions

diff --git a/hw/intc/xive2.c b/hw/intc/xive2.c
index fc5aed3..cd075e4 100644
--- a/hw/intc/xive2.c
+++ b/hw/intc/xive2.c
@@ -1,10 +1,9 @@
 /*
  * QEMU PowerPC XIVE2 interrupt controller model (POWER10)
  *
- * Copyright (c) 2019-2022, IBM Corporation..
+ * Copyright (c) 2019-2024, IBM Corporation..
  *
- * This code is licensed under the GPL version 2 or later. See the
- * COPYING file in the top-level directory.
+ * SPDX-License-Identifier: GPL-2.0-or-later
  */
 
 #include "qemu/osdep.h"
@@ -313,7 +312,19 @@ static void xive2_tctx_save_ctx(Xive2Router *xrtr, XiveTCTX *tctx,
 
     nvp.w2 = xive_set_field32(NVP2_W2_IPB, nvp.w2, regs[TM_IPB]);
     nvp.w2 = xive_set_field32(NVP2_W2_CPPR, nvp.w2, regs[TM_CPPR]);
-    nvp.w2 = xive_set_field32(NVP2_W2_LSMFB, nvp.w2, regs[TM_LSMFB]);
+    if (nvp.w0 & NVP2_W0_L) {
+        /*
+         * Typically not used. If LSMFB is restored with 0, it will
+         * force a backlog rescan
+         */
+        nvp.w2 = xive_set_field32(NVP2_W2_LSMFB, nvp.w2, regs[TM_LSMFB]);
+    }
+    if (nvp.w0 & NVP2_W0_G) {
+        nvp.w2 = xive_set_field32(NVP2_W2_LGS, nvp.w2, regs[TM_LGS]);
+    }
+    if (nvp.w0 & NVP2_W0_T) {
+        nvp.w2 = xive_set_field32(NVP2_W2_T, nvp.w2, regs[TM_T]);
+    }
     xive2_router_write_nvp(xrtr, nvp_blk, nvp_idx, &nvp, 2);
 
     nvp.w1 = xive_set_field32(NVP2_W1_CO, nvp.w1, 0);
@@ -527,7 +538,9 @@ static uint8_t xive2_tctx_restore_os_ctx(Xive2Router *xrtr, XiveTCTX *tctx,
     xive2_router_write_nvp(xrtr, nvp_blk, nvp_idx, nvp, 2);
 
     tctx->regs[TM_QW1_OS + TM_CPPR] = cppr;
-    /* we don't model LSMFB */
+    tctx->regs[TM_QW1_OS + TM_LSMFB] = xive_get_field32(NVP2_W2_LSMFB, nvp->w2);
+    tctx->regs[TM_QW1_OS + TM_LGS] = xive_get_field32(NVP2_W2_LGS, nvp->w2);
+    tctx->regs[TM_QW1_OS + TM_T] = xive_get_field32(NVP2_W2_T, nvp->w2);
 
     nvp->w1 = xive_set_field32(NVP2_W1_CO, nvp->w1, 1);
     nvp->w1 = xive_set_field32(NVP2_W1_CO_THRID_VALID, nvp->w1, 1);
diff --git a/include/hw/ppc/xive2_regs.h b/include/hw/ppc/xive2_regs.h
index 1d00c8d..e88d6ea 100644
--- a/include/hw/ppc/xive2_regs.h
+++ b/include/hw/ppc/xive2_regs.h
@@ -1,10 +1,9 @@
 /*
  * QEMU PowerPC XIVE2 internal structure definitions (POWER10)
  *
- * Copyright (c) 2019-2022, IBM Corporation.
+ * Copyright (c) 2019-2024, IBM Corporation.
  *
- * This code is licensed under the GPL version 2 or later. See the
- * COPYING file in the top-level directory.
+ * SPDX-License-Identifier: GPL-2.0-or-later
  */
 
 #ifndef PPC_XIVE2_REGS_H
@@ -152,6 +151,9 @@ typedef struct Xive2Nvp {
         uint32_t       w0;
 #define NVP2_W0_VALID              PPC_BIT32(0)
 #define NVP2_W0_HW                 PPC_BIT32(7)
+#define NVP2_W0_L                  PPC_BIT32(8)
+#define NVP2_W0_G                  PPC_BIT32(9)
+#define NVP2_W0_T                  PPC_BIT32(10)
 #define NVP2_W0_ESC_END            PPC_BIT32(25) /* 'N' bit 0:ESB  1:END */
 #define NVP2_W0_PGOFIRST           PPC_BITMASK32(26, 31)
         uint32_t       w1;
@@ -163,6 +165,8 @@ typedef struct Xive2Nvp {
 #define NVP2_W2_CPPR               PPC_BITMASK32(0, 7)
 #define NVP2_W2_IPB                PPC_BITMASK32(8, 15)
 #define NVP2_W2_LSMFB              PPC_BITMASK32(16, 23)
+#define NVP2_W2_T                  PPC_BIT32(27)
+#define NVP2_W2_LGS                PPC_BITMASK32(28, 31)
         uint32_t       w3;
         uint32_t       w4;
 #define NVP2_W4_ESC_ESB_BLOCK      PPC_BITMASK32(0, 3)  /* N:0 */