According to PAPR:
R1–7.3.30–3. When the platform receives an ibm,os-term RTAS call, or
on a system reset without an ibm,nmi-interlock RTAS call, if the
platform has a dump structure registered through the
ibm,configure-kernel-dump call, the platform must process each
registered kernel dump section as required and, when available,
present the dump structure information to the operating system
through the “ibm,kernel-dump” property, updated with status for each
dump section, until the dump has been invalidated through the
ibm,configure-kernel-dump RTAS call.
If Fadump has been registered, trigger an Fadump boot (memory preserving
boot), if QEMU recieves a 'ibm,os-term' rtas call.
Implementing the fadump boot as:
* pause all vcpus (will save registers later)
* preserve memory regions specified by fadump
* do a memory preserving reboot (GUEST_RESET in QEMU doesn't clear
the memory)
Memory regions registered by fadump will be handled in a later patch.
Signed-off-by: Aditya Gupta <[email protected]>
---
hw/ppc/spapr_rtas.c | 42 ++++++++++++++++++++++++++++++++++++++++++
1 file changed, 42 insertions(+)
diff --git a/hw/ppc/spapr_rtas.c b/hw/ppc/spapr_rtas.c
index eebdf13b1552..01c82375f03d 100644
--- a/hw/ppc/spapr_rtas.c
+++ b/hw/ppc/spapr_rtas.c
@@ -342,6 +342,43 @@ static void rtas_ibm_set_system_parameter(PowerPCCPU *cpu,
}
struct fadump_metadata fadump_metadata;
+bool is_next_boot_fadump;
+
+static void trigger_fadump_boot(target_ulong spapr_retcode)
+{
+ /*
+ * In PowerNV, SBE stops all clocks for cores, do similar to it
+ * QEMU's nearest equivalent is 'pause_all_vcpus'
+ * See 'stopClocksS0' in SBE source code for more info on SBE part
+ */
+ pause_all_vcpus();
+
+ if (true /* TODO: Preserve memory registered for fadump */) {
+ /* Failed to preserve the registered memory regions */
+ rtas_st(spapr_retcode, 0, RTAS_OUT_HW_ERROR);
+
+ /* Cause a reboot */
+ qemu_system_guest_panicked(NULL);
+ return;
+ }
+
+ /* Mark next boot as fadump boot */
+ is_next_boot_fadump = true;
+
+ /* Reset fadump_registered for next boot */
+ fadump_metadata.fadump_registered = false;
+ fadump_metadata.fadump_dump_active = true;
+
+ /* Then do a guest reset */
+ /*
+ * Requirement:
+ * This guest reset should not clear the memory (which is
+ * the case when this is merged)
+ */
+ qemu_system_reset_request(SHUTDOWN_CAUSE_GUEST_RESET);
+
+ rtas_st(spapr_retcode, 0, RTAS_OUT_SUCCESS);
+}
/* Papr Section 7.4.9 ibm,configure-kernel-dump RTAS call */
static __attribute((unused)) void rtas_configure_kernel_dump(PowerPCCPU *cpu,
@@ -449,6 +486,11 @@ static void rtas_ibm_os_term(PowerPCCPU *cpu,
target_ulong msgaddr = rtas_ld(args, 0);
char msg[512];
+ if (fadump_metadata.fadump_registered) {
+ /* If fadump boot works, control won't come back here */
+ return trigger_fadump_boot(rets);
+ }
+
cpu_physical_memory_read(msgaddr, msg, sizeof(msg) - 1);
msg[sizeof(msg) - 1] = 0;
--
2.48.1
