ppc/pnv: add initial IPMI sensors for the BMC simulator

Skiboot, the firmware for the PowerNV platform, expects the BMC to
provide some specific IPMI sensors. These sensors are exposed in the
device tree and their values are updated by the firmware at boot time.

Sensors of interest are :

	"FW Boot Progress"
	"Boot Count"

As such a device is defined on the command line, we can only detect
its presence at reset time.
Signed-off-by: NCédric Le Goater <clg@kaod.org>
Reviewed-by: NDavid Gibson <david@gibson.dropbear.id.au>
Signed-off-by: NDavid Gibson <david@gibson.dropbear.id.au>

hw/ppc/Makefile.objs

@@ -6,7 +6,7 @@ obj-$(CONFIG_PSERIES) += spapr_hcall.o spapr_iommu.o spapr_rtas.o
 obj-$(CONFIG_PSERIES) += spapr_pci.o spapr_rtc.o spapr_drc.o spapr_rng.o
 obj-$(CONFIG_PSERIES) += spapr_cpu_core.o spapr_ovec.o
 # IBM PowerNV
-obj-$(CONFIG_POWERNV) += pnv.o pnv_xscom.o pnv_core.o pnv_lpc.o pnv_psi.o pnv_occ.o
+obj-$(CONFIG_POWERNV) += pnv.o pnv_xscom.o pnv_core.o pnv_lpc.o pnv_psi.o pnv_occ.o pnv_bmc.o
 ifeq ($(CONFIG_PCI)$(CONFIG_PSERIES)$(CONFIG_LINUX), yyy)
 obj-y += spapr_pci_vfio.o
 endif

hw/ppc/pnv.c

@@ -35,6 +35,7 @@
 #include "qapi/visitor.h"
 #include "monitor/monitor.h"
 #include "hw/intc/intc.h"
+#include "hw/ipmi/ipmi.h"
 
 #include "hw/ppc/xics.h"
 #include "hw/ppc/pnv_xscom.h"
@@ -476,16 +477,36 @@ static void *powernv_create_fdt(MachineState *machine)
     /* Populate ISA devices on chip 0 */
     lpc_offset = pnv_chip_lpc_offset(pnv->chips[0], fdt);
     powernv_populate_isa(pnv->isa_bus, fdt, lpc_offset);
+
+    if (pnv->bmc) {
+        pnv_bmc_populate_sensors(pnv->bmc, fdt);
+    }
+
     return fdt;
 }
 
 static void ppc_powernv_reset(void)
 {
     MachineState *machine = MACHINE(qdev_get_machine());
+    PnvMachineState *pnv = POWERNV_MACHINE(machine);
     void *fdt;
+    Object *obj;
 
     qemu_devices_reset();
 
+    /* OpenPOWER systems have a BMC, which can be defined on the
+     * command line with:
+     *
+     *   -device ipmi-bmc-sim,id=bmc0
+     *
+     * This is the internal simulator but it could also be an external
+     * BMC.
+     */
+    obj = object_resolve_path_type("", TYPE_IPMI_BMC, NULL);
+    if (obj) {
+        pnv->bmc = IPMI_BMC(obj);
+    }
+
     fdt = powernv_create_fdt(machine);
 
     /* Pack resulting tree */

hw/ppc/pnv_bmc.c

+/*
+ * QEMU PowerNV, BMC related functions
+ *
+ * Copyright (c) 2016-2017, IBM Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License, version 2, as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include "qemu/osdep.h"
+#include "hw/hw.h"
+#include "sysemu/sysemu.h"
+#include "target/ppc/cpu.h"
+#include "qapi/error.h"
+#include "qemu/log.h"
+#include "hw/ipmi/ipmi.h"
+#include "hw/ppc/fdt.h"
+
+#include "hw/ppc/pnv.h"
+
+#include <libfdt.h>
+
+/* TODO: include definition in ipmi.h */
+#define IPMI_SDR_FULL_TYPE 1
+
+void pnv_bmc_populate_sensors(IPMIBmc *bmc, void *fdt)
+{
+    int offset;
+    int i;
+    const struct ipmi_sdr_compact *sdr;
+    uint16_t nextrec;
+
+    offset = fdt_add_subnode(fdt, 0, "/bmc");
+    _FDT(offset);
+
+    _FDT((fdt_setprop_string(fdt, offset, "name", "bmc")));
+    _FDT((fdt_setprop_cell(fdt, offset, "#address-cells", 0x1)));
+    _FDT((fdt_setprop_cell(fdt, offset, "#size-cells", 0x0)));
+
+    offset = fdt_add_subnode(fdt, offset, "sensors");
+    _FDT(offset);
+
+    _FDT((fdt_setprop_cell(fdt, offset, "#address-cells", 0x1)));
+    _FDT((fdt_setprop_cell(fdt, offset, "#size-cells", 0x0)));
+
+    for (i = 0; !ipmi_bmc_sdr_find(bmc, i, &sdr, &nextrec); i++) {
+        int off;
+        char *name;
+
+        if (sdr->header.rec_type != IPMI_SDR_COMPACT_TYPE &&
+            sdr->header.rec_type != IPMI_SDR_FULL_TYPE) {
+            continue;
+        }
+
+        name = g_strdup_printf("sensor@%x", sdr->sensor_owner_number);
+        off = fdt_add_subnode(fdt, offset, name);
+        _FDT(off);
+        g_free(name);
+
+        _FDT((fdt_setprop_cell(fdt, off, "reg", sdr->sensor_owner_number)));
+        _FDT((fdt_setprop_string(fdt, off, "name", "sensor")));
+        _FDT((fdt_setprop_string(fdt, off, "compatible", "ibm,ipmi-sensor")));
+        _FDT((fdt_setprop_cell(fdt, off, "ipmi-sensor-reading-type",
+                               sdr->reading_type)));
+        _FDT((fdt_setprop_cell(fdt, off, "ipmi-entity-id",
+                               sdr->entity_id)));
+        _FDT((fdt_setprop_cell(fdt, off, "ipmi-entity-instance",
+                               sdr->entity_instance)));
+        _FDT((fdt_setprop_cell(fdt, off, "ipmi-sensor-type",
+                               sdr->sensor_type)));
+    }
+}

include/hw/ppc/pnv.h

@@ -118,6 +118,8 @@ typedef struct PnvChipClass {
 #define POWERNV_MACHINE(obj) \
     OBJECT_CHECK(PnvMachineState, (obj), TYPE_POWERNV_MACHINE)
 
+typedef struct IPMIBmc IPMIBmc;
+
 typedef struct PnvMachineState {
     /*< private >*/
     MachineState parent_obj;
@@ -130,11 +132,18 @@ typedef struct PnvMachineState {
 
     ISABus       *isa_bus;
     uint32_t     cpld_irqstate;
+
+    IPMIBmc      *bmc;
 } PnvMachineState;
 
 #define PNV_FDT_ADDR          0x01000000
 #define PNV_TIMEBASE_FREQ     512000000ULL
 
+/*
+ * BMC helpers
+ */
+void pnv_bmc_populate_sensors(IPMIBmc *bmc, void *fdt);
+
 /*
  * POWER8 MMIO base addresses
  */