ppc/spapr: Move GPRs setup to one place

At the moment "pseries" starts in SLOF which only expects the FDT blob
pointer in r3. As we are going to introduce a OpenFirmware support in
QEMU, we will be booting OF clients directly and these expect a stack
pointer in r1, Linux looks at r3/r4 for the initramdisk location
(although vmlinux can find this from the device tree but zImage from
distro kernels cannot).

This extends spapr_cpu_set_entry_state() to take more registers. This
should cause no behavioral change.

Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Message-Id: <20200310050733.29805-2-aik@ozlabs.ru>
Reviewed-by: Greg Kurz <groug@kaod.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>

hw/ppc/spapr.c

@@ -1698,7 +1698,7 @@ static void spapr_machine_reset(MachineState *machine)
     spapr->fdt_blob = fdt;
 
     /* Set up the entry state */
-    spapr_cpu_set_entry_state(first_ppc_cpu, SPAPR_ENTRY_POINT, fdt_addr);
+    spapr_cpu_set_entry_state(first_ppc_cpu, SPAPR_ENTRY_POINT, 0, fdt_addr, 0);
     first_ppc_cpu->env.gpr[5] = 0;
 
     spapr->cas_reboot = false;

hw/ppc/spapr_cpu_core.c

@@ -76,13 +76,17 @@ static void spapr_reset_vcpu(PowerPCCPU *cpu)
     spapr_irq_cpu_intc_reset(spapr, cpu);
 }
 
-void spapr_cpu_set_entry_state(PowerPCCPU *cpu, target_ulong nip, target_ulong r3)
+void spapr_cpu_set_entry_state(PowerPCCPU *cpu, target_ulong nip,
+                               target_ulong r1, target_ulong r3,
+                               target_ulong r4)
 {
     PowerPCCPUClass *pcc = POWERPC_CPU_GET_CLASS(cpu);
     CPUPPCState *env = &cpu->env;
 
     env->nip = nip;
+    env->gpr[1] = r1;
     env->gpr[3] = r3;
+    env->gpr[4] = r4;
     kvmppc_set_reg_ppc_online(cpu, 1);
     CPU(cpu)->halted = 0;
     /* Enable Power-saving mode Exit Cause exceptions */

hw/ppc/spapr_rtas.c

@@ -190,7 +190,7 @@ static void rtas_start_cpu(PowerPCCPU *callcpu, SpaprMachineState *spapr,
      */
     newcpu->env.tb_env->tb_offset = callcpu->env.tb_env->tb_offset;
 
-    spapr_cpu_set_entry_state(newcpu, start, r3);
+    spapr_cpu_set_entry_state(newcpu, start, 0, r3, 0);
 
     qemu_cpu_kick(CPU(newcpu));
 

include/hw/ppc/spapr_cpu_core.h

@@ -40,7 +40,9 @@ typedef struct SpaprCpuCoreClass {
 } SpaprCpuCoreClass;
 
 const char *spapr_get_cpu_core_type(const char *cpu_type);
-void spapr_cpu_set_entry_state(PowerPCCPU *cpu, target_ulong nip, target_ulong r3);
+void spapr_cpu_set_entry_state(PowerPCCPU *cpu, target_ulong nip,
+                               target_ulong r1, target_ulong r3,
+                               target_ulong r4);
 
 typedef struct SpaprCpuState {
     uint64_t vpa_addr;