@@ -736,21 +736,27 @@ static void pnv_reset(MachineState *machine, ShutdownCause reason)
}
}
- fdt = pnv_dt_create(machine);
-
- /* Pack resulting tree */
- _FDT((fdt_pack(fdt)));
+ if (machine->fdt) {
+ fdt = machine->fdt;
+ } else {
+ fdt = pnv_dt_create(machine);
+ /* Pack resulting tree */
+ _FDT((fdt_pack(fdt)));
+ }
qemu_fdt_dumpdtb(fdt, fdt_totalsize(fdt));
cpu_physical_memory_write(PNV_FDT_ADDR, fdt, fdt_totalsize(fdt));
- /*
- * Set machine->fdt for 'dumpdtb' QMP/HMP command. Free
- * the existing machine->fdt to avoid leaking it during
- * a reset.
- */
- g_free(machine->fdt);
- machine->fdt = fdt;
+ /* Update machine->fdt with latest fdt */
+ if (machine->fdt != fdt) {
+ /*
+ * Set machine->fdt for 'dumpdtb' QMP/HMP command. Free
+ * the existing machine->fdt to avoid leaking it during
+ * a reset.
+ */
+ g_free(machine->fdt);
+ machine->fdt = fdt;
+ }
}
static ISABus *pnv_chip_power8_isa_create(PnvChip *chip, Error **errp)
@@ -952,6 +958,14 @@ static void pnv_init(MachineState *machine)
g_free(sz);
exit(EXIT_FAILURE);
}
+
+ /* checks for invalid option combinations */
+ if (machine->dtb && (strlen(machine->kernel_cmdline) != 0)) {
+ error_report("-append and -dtb cannot be used together, as passed"
+ " command line is ignored in case of custom dtb");
+ exit(EXIT_FAILURE);
+ }
+
memory_region_add_subregion(get_system_memory(), 0, machine->ram);
/*
@@ -1003,6 +1017,21 @@ static void pnv_init(MachineState *machine)
}
}
+ /* load dtb if passed */
+ if (machine->dtb) {
+ int fdt_size;
+
+ warn_report("with manually passed dtb, some options like '-append'"
+ " will get ignored and the dtb passed will be used as-is");
+
+ /* read the file 'machine->dtb', and load it into 'fdt' buffer */
+ machine->fdt = load_device_tree(machine->dtb, &fdt_size);
+ if (!machine->fdt) {
+ error_report("Could not load dtb '%s'", machine->dtb);
+ exit(1);
+ }
+ }
+
/* MSIs are supported on this platform */
msi_nonbroken = true;
Currently any device tree passed with -dtb option in QEMU, was ignored by the PowerNV code. Read and pass the passed -dtb to the kernel, thus enabling easier debugging with custom DTBs. The existing behaviour when -dtb is 'not' passed, is preserved as-is. But when a '-dtb' is passed, it completely overrides any dtb nodes or changes QEMU might have done, such as '-append' arguments to the kernel (which are mentioned in /chosen/bootargs in the dtb), hence add warning when -dtb is being used Signed-off-by: Aditya Gupta <adityag@linux.ibm.com> --- Changelog =========== v4: + use 'MachineState::fdt' instead of 'PnvMachineState::fdt' + added an 'if' check at end of pnv_reset, so we don't free the fdt we are using v3: + use 'load_device_tree' to read the device tree, instead of g_file_get_contents + tested that passed dtb does NOT get ignored on system_reset v2: + move reading dtb and warning to pnv_init v1: + use 'g_file_get_contents' and add check for -append & -dtb as suggested by Daniel --- --- hw/ppc/pnv.c | 51 ++++++++++++++++++++++++++++++++++++++++----------- 1 file changed, 40 insertions(+), 11 deletions(-)