ppc/pnv: Add POWER9/10 chiptod model

The ChipTOD (for Time-Of-Day) is a chip pervasive facility in IBM POWER
(powernv) processors that keeps a time of day clock.

In particular for this model are facilities that initialise and start
the time of day clock, and that synchronise that clock to cores on the
chip, and to other chips. In this way, all cores on all chips can
synchronise timebase (TB).

This model implements functionality sufficient to run the skiboot
chiptod synchronisation procedure (with the following core timebase
state machine implementation). It does not modify the TB in the cores
where the real hardware would, because the QEMU ppc timebase
implementation is always synchronised acros all cores.

Reviewed-by: Cédric Le Goater <clg@kaod.org>
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>

2 files changed, 58 insertions, 0 deletions

diff --git a/include/hw/ppc/pnv_chiptod.h b/include/hw/ppc/pnv_chiptod.h
new file mode 100644
index 0000000000..ca770525d9
--- /dev/null
+++ b/include/hw/ppc/pnv_chiptod.h
@@ -0,0 +1,49 @@
+/*
+ * QEMU PowerPC PowerNV Emulation of some CHIPTOD behaviour
+ *
+ * Copyright (c) 2022-2023, IBM Corporation.
+ *
+ * SPDX-License-Identifier: GPL-2.0-or-later
+ */
+
+#ifndef PPC_PNV_CHIPTOD_H
+#define PPC_PNV_CHIPTOD_H
+
+#include "qom/object.h"
+
+#define TYPE_PNV_CHIPTOD "pnv-chiptod"
+OBJECT_DECLARE_TYPE(PnvChipTOD, PnvChipTODClass, PNV_CHIPTOD)
+#define TYPE_PNV9_CHIPTOD TYPE_PNV_CHIPTOD "-POWER9"
+DECLARE_INSTANCE_CHECKER(PnvChipTOD, PNV9_CHIPTOD, TYPE_PNV9_CHIPTOD)
+#define TYPE_PNV10_CHIPTOD TYPE_PNV_CHIPTOD "-POWER10"
+DECLARE_INSTANCE_CHECKER(PnvChipTOD, PNV10_CHIPTOD, TYPE_PNV10_CHIPTOD)
+
+enum tod_state {
+    tod_error = 0,
+    tod_not_set = 7,
+    tod_running = 2,
+    tod_stopped = 1,
+};
+
+struct PnvChipTOD {
+    DeviceState xd;
+
+    PnvChip *chip;
+    MemoryRegion xscom_regs;
+
+    bool primary;
+    bool secondary;
+    enum tod_state tod_state;
+    uint64_t tod_error;
+    uint64_t pss_mss_ctrl_reg;
+};
+
+struct PnvChipTODClass {
+    DeviceClass parent_class;
+
+    void (*broadcast_ttype)(PnvChipTOD *sender, uint32_t trigger);
+
+    int xscom_size;
+};
+
+#endif /* PPC_PNV_CHIPTOD_H */
diff --git a/include/hw/ppc/pnv_xscom.h b/include/hw/ppc/pnv_xscom.h
index 535ae1dab0..6209e18492 100644
--- a/include/hw/ppc/pnv_xscom.h
+++ b/include/hw/ppc/pnv_xscom.h
@@ -64,6 +64,9 @@ struct PnvXScomInterfaceClass {
 #define PNV_XSCOM_PSIHB_BASE      0x2010900
 #define PNV_XSCOM_PSIHB_SIZE      0x20
 
+#define PNV_XSCOM_CHIPTOD_BASE    0x0040000
+#define PNV_XSCOM_CHIPTOD_SIZE    0x31
+
 #define PNV_XSCOM_OCC_BASE        0x0066000
 #define PNV_XSCOM_OCC_SIZE        0x6000
 
@@ -93,6 +96,9 @@ struct PnvXScomInterfaceClass {
 #define PNV9_XSCOM_I2CM_BASE      0xa0000
 #define PNV9_XSCOM_I2CM_SIZE      0x1000
 
+#define PNV9_XSCOM_CHIPTOD_BASE   PNV_XSCOM_CHIPTOD_BASE
+#define PNV9_XSCOM_CHIPTOD_SIZE   PNV_XSCOM_CHIPTOD_SIZE
+
 #define PNV9_XSCOM_OCC_BASE       PNV_XSCOM_OCC_BASE
 #define PNV9_XSCOM_OCC_SIZE       0x8000
 
@@ -155,6 +161,9 @@ struct PnvXScomInterfaceClass {
 #define PNV10_XSCOM_I2CM_BASE      PNV9_XSCOM_I2CM_BASE
 #define PNV10_XSCOM_I2CM_SIZE      PNV9_XSCOM_I2CM_SIZE
 
+#define PNV10_XSCOM_CHIPTOD_BASE   PNV9_XSCOM_CHIPTOD_BASE
+#define PNV10_XSCOM_CHIPTOD_SIZE   PNV9_XSCOM_CHIPTOD_SIZE
+
 #define PNV10_XSCOM_OCC_BASE       PNV9_XSCOM_OCC_BASE
 #define PNV10_XSCOM_OCC_SIZE       PNV9_XSCOM_OCC_SIZE