pnv/mpipl: Set thread entry size to be allocated by firmware
Set the "Thread Register State Entry Size" that is required by firmware (OPAL), to know size of memory to allocate to capture CPU state, in the event of a crash Reviewed-by: Hari Bathini <hbathini@linux.ibm.com> Reviewed-by: Sourabh Jain <sourabhjain@linux.ibm.com> Signed-off-by: Aditya Gupta <adityag@linux.ibm.com> Tested-by: Shivang Upadhyay <shivangu@linux.ibm.com> Link: https://lore.kernel.org/qemu-devel/20260424083837.214947-7-adityag@linux.ibm.com Signed-off-by: Harsh Prateek Bora <harshpb@linux.ibm.com>
Aditya Gupta committed
Apr 24, 2026 at 14:08 UTC
4cb8c9d6a3998fb51659ce8de623c152eaf9e53c
1 file changed
+25
hw/ppc/pnv.c
+25
@@ -748,10 +748,35 @@ static void pnv_powerdown_notify(Notifier *n, void *opaque)
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static void pnv_reset(MachineState *machine, ResetType type)
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{
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+ PnvMachineState *pnv = PNV_MACHINE(machine);
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void *fdt;
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qemu_devices_reset(type);
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+ if (!pnv->mpipl_state.is_next_boot_mpipl) {
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+ /*
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+ * Set the "Thread Register State Entry Size", so that firmware can
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+ * allocate enough memory to capture CPU state in the event of a
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+ * crash
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+ */
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+
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+ MpiplProcDumpArea proc_area;
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+
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+ proc_area.version = PROC_DUMP_AREA_VERSION_P9;
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+ proc_area.thread_size = cpu_to_be32(sizeof(MpiplPreservedCPUState));
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+
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+ /* These are to be allocated & assigned by the firmware */
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+ proc_area.alloc_addr = 0;
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+ proc_area.alloc_size = 0;
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+
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+ /* These get assigned after crash, when QEMU preserves the registers */
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+ proc_area.dest_addr = 0;
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+ proc_area.act_size = 0;
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+
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+ cpu_physical_memory_write(PROC_DUMP_AREA_OFF, &proc_area,
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+ sizeof(proc_area));
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+ }
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+
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fdt = machine->fdt;
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cpu_physical_memory_write(PNV_FDT_ADDR, fdt, fdt_totalsize(fdt));
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}