ppc/pnv: Add support for "hostboot" mode

When the "hb-mode" option is activated on the powernv machine, the
firmware is mapped at 0x8000000 and the HRMOR of the HW threads are
set to the same address.

The PNOR mapping on the FW address space of the LPC bus is left enabled
to let the firmware load any other images required to boot the host.

Signed-off-by: Cédric Le Goater <clg@kaod.org>
Message-Id: <20200127144154.10170-4-clg@kaod.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>

hw/ppc/pnv.c

@@ -716,7 +716,7 @@ static void pnv_init(MachineState *machine)
         exit(1);
     }
 
-    fw_size = load_image_targphys(fw_filename, FW_LOAD_ADDR, FW_MAX_SIZE);
+    fw_size = load_image_targphys(fw_filename, pnv->fw_load_addr, FW_MAX_SIZE);
     if (fw_size < 0) {
         error_report("Could not load OPAL firmware '%s'", fw_filename);
         exit(1);
@@ -1533,6 +1533,7 @@ static void pnv_chip_core_realize(PnvChip *chip, Error **errp)
     PnvChipClass *pcc = PNV_CHIP_GET_CLASS(chip);
     const char *typename = pnv_chip_core_typename(chip);
     int i, core_hwid;
+    PnvMachineState *pnv = PNV_MACHINE(qdev_get_machine());
 
     if (!object_class_by_name(typename)) {
         error_setg(errp, "Unable to find PowerNV CPU Core '%s'", typename);
@@ -1571,6 +1572,8 @@ static void pnv_chip_core_realize(PnvChip *chip, Error **errp)
         object_property_set_int(OBJECT(pnv_core),
                                 pcc->core_pir(chip, core_hwid),
                                 "pir", &error_fatal);
+        object_property_set_int(OBJECT(pnv_core), pnv->fw_load_addr,
+                                "hrmor", &error_fatal);
         object_property_set_link(OBJECT(pnv_core), OBJECT(chip), "chip",
                                  &error_abort);
         object_property_set_bool(OBJECT(pnv_core), true, "realized",
@@ -1767,6 +1770,22 @@ static void pnv_machine_power10_class_init(ObjectClass *oc, void *data)
     pmc->dt_power_mgt = pnv_dt_power_mgt;
 }
 
+static bool pnv_machine_get_hb(Object *obj, Error **errp)
+{
+    PnvMachineState *pnv = PNV_MACHINE(obj);
+
+    return !!pnv->fw_load_addr;
+}
+
+static void pnv_machine_set_hb(Object *obj, bool value, Error **errp)
+{
+    PnvMachineState *pnv = PNV_MACHINE(obj);
+
+    if (value) {
+        pnv->fw_load_addr = 0x8000000;
+    }
+}
+
 static void pnv_machine_class_init(ObjectClass *oc, void *data)
 {
     MachineClass *mc = MACHINE_CLASS(oc);
@@ -1786,6 +1805,13 @@ static void pnv_machine_class_init(ObjectClass *oc, void *data)
      */
     mc->default_ram_size = INITRD_LOAD_ADDR + INITRD_MAX_SIZE;
     ispc->print_info = pnv_pic_print_info;
+
+    object_class_property_add_bool(oc, "hb-mode",
+                                   pnv_machine_get_hb, pnv_machine_set_hb,
+                                   &error_abort);
+    object_class_property_set_description(oc, "hb-mode",
+                              "Use a hostboot like boot loader",
+                              NULL);
 }
 
 #define DEFINE_PNV8_CHIP_TYPE(type, class_initfn) \

hw/ppc/pnv_core.c

@@ -56,6 +56,8 @@ static void pnv_core_cpu_reset(PnvCore *pc, PowerPCCPU *cpu)
     env->nip = 0x10;
     env->msr |= MSR_HVB; /* Hypervisor mode */
 
+    env->spr[SPR_HRMOR] = pc->hrmor;
+
     pcc->intc_reset(pc->chip, cpu);
 }
 
@@ -289,6 +291,7 @@ static void pnv_core_unrealize(DeviceState *dev, Error **errp)
 
 static Property pnv_core_properties[] = {
     DEFINE_PROP_UINT32("pir", PnvCore, pir, 0),
+    DEFINE_PROP_UINT64("hrmor", PnvCore, hrmor, 0),
     DEFINE_PROP_LINK("chip", PnvCore, chip, TYPE_PNV_CHIP, PnvChip *),
     DEFINE_PROP_END_OF_LIST(),
 };

hw/ppc/pnv_lpc.c

@@ -825,6 +825,7 @@ ISABus *pnv_lpc_isa_create(PnvLpcController *lpc, bool use_cpld, Error **errp)
     qemu_irq *irqs;
     qemu_irq_handler handler;
     PnvMachineState *pnv = PNV_MACHINE(qdev_get_machine());
+    bool hostboot_mode = !!pnv->fw_load_addr;
 
     /* let isa_bus_new() create its own bridge on SysBus otherwise
      * devices speficied on the command line won't find the bus and
@@ -859,7 +860,9 @@ ISABus *pnv_lpc_isa_create(PnvLpcController *lpc, bool use_cpld, Error **errp)
      * Start disabled. The HIOMAP protocol will activate the mapping
      * with HIOMAP_C_CREATE_WRITE_WINDOW
      */
-    memory_region_set_enabled(&pnv->pnor->mmio, false);
+    if (!hostboot_mode) {
+        memory_region_set_enabled(&pnv->pnor->mmio, false);
+    }
 
     return isa_bus;
 }

include/hw/ppc/pnv.h

@@ -217,6 +217,8 @@ struct PnvMachineState {
     Notifier     powerdown_notifier;
 
     PnvPnor      *pnor;
+
+    hwaddr       fw_load_addr;
 };
 
 #define PNV_FDT_ADDR          0x01000000

include/hw/ppc/pnv_core.h

@@ -40,6 +40,7 @@ typedef struct PnvCore {
     /*< public >*/
     PowerPCCPU **threads;
     uint32_t pir;
+    uint64_t hrmor;
     PnvChip *chip;
 
     MemoryRegion xscom_regs;