[Qemu-devel] [PATCH v4 9/9] ppc/pnv: add memory regions for the ICP registers

["Cédric Le Goater" <clg@kaod.org>]

This provides to a PowerNV chip (POWER8) access to the Interrupt
Management area, which contains the registers of the Interrupt Control
Presenters of each thread. These are used to accept, return, forward
interrupts in the system.

This area is modeled with a per-chip container memory region holding
all the ICP registers. Each thread of a chip is then associated with
its ICP registers using a memory subregion indexed by its PIR number
in the overall region.

The device tree is populated accordingly.

Signed-off-by: Cédric Le Goater <clg@kaod.org>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
---
 Changes since v1:

 - added multichip support
 - adapted to use PnvICPState object

 hw/ppc/pnv.c         | 81 ++++++++++++++++++++++++++++++++++++++++++++++++++++
 include/hw/ppc/pnv.h | 19 ++++++++++++
 2 files changed, 100 insertions(+)

diff --git a/hw/ppc/pnv.c b/hw/ppc/pnv.c
index 15a908f4306a..eb91d0187890 100644
--- a/hw/ppc/pnv.c
+++ b/hw/ppc/pnv.c
@@ -218,6 +218,43 @@ static void powernv_create_core_node(PnvChip *chip, PnvCore *pc, void *fdt)
                        servers_prop, sizeof(servers_prop))));
 }
 
+static void powernv_populate_icp(PnvChip *chip, void *fdt, uint32_t pir,
+                                 uint32_t nr_threads)
+{
+    uint64_t addr = PNV_ICP_BASE(chip) | (pir << 12);
+    char *name;
+    const char compat[] = "IBM,power8-icp\0IBM,ppc-xicp";
+    uint32_t irange[2], i, rsize;
+    uint64_t *reg;
+    int offset;
+
+    irange[0] = cpu_to_be32(pir);
+    irange[1] = cpu_to_be32(nr_threads);
+
+    rsize = sizeof(uint64_t) * 2 * nr_threads;
+    reg = g_malloc(rsize);
+    for (i = 0; i < nr_threads; i++) {
+        reg[i * 2] = cpu_to_be64(addr | ((pir + i) * 0x1000));
+        reg[i * 2 + 1] = cpu_to_be64(0x1000);
+    }
+
+    name = g_strdup_printf("interrupt-controller@%"PRIX64, addr);
+    offset = fdt_add_subnode(fdt, 0, name);
+    _FDT(offset);
+    g_free(name);
+
+    _FDT((fdt_setprop(fdt, offset, "compatible", compat, sizeof(compat))));
+    _FDT((fdt_setprop(fdt, offset, "reg", reg, rsize)));
+    _FDT((fdt_setprop_string(fdt, offset, "device_type",
+                              "PowerPC-External-Interrupt-Presentation")));
+    _FDT((fdt_setprop(fdt, offset, "interrupt-controller", NULL, 0)));
+    _FDT((fdt_setprop(fdt, offset, "ibm,interrupt-server-ranges",
+                       irange, sizeof(irange))));
+    _FDT((fdt_setprop_cell(fdt, offset, "#interrupt-cells", 1)));
+    _FDT((fdt_setprop_cell(fdt, offset, "#address-cells", 0)));
+    g_free(reg);
+}
+
 static void powernv_populate_chip(PnvChip *chip, void *fdt)
 {
     PnvChipClass *pcc = PNV_CHIP_GET_CLASS(chip);
@@ -231,6 +268,10 @@ static void powernv_populate_chip(PnvChip *chip, void *fdt)
         PnvCore *pnv_core = PNV_CORE(chip->cores + i * typesize);
 
         powernv_create_core_node(chip, pnv_core, fdt);
+
+        /* Interrupt Control Presenters (ICP). One per core. */
+        powernv_populate_icp(chip, fdt, pnv_core->pir,
+                             CPU_CORE(pnv_core)->nr_threads);
     }
 
     if (chip->ram_size) {
@@ -643,6 +684,38 @@ static void pnv_chip_init(Object *obj)
     object_property_add_child(obj, "lpc", OBJECT(&chip->lpc), NULL);
 }
 
+static void pnv_chip_icp_realize(PnvChip *chip, Error **errp)
+{
+    PnvChipClass *pcc = PNV_CHIP_GET_CLASS(chip);
+    char *typename = pnv_core_typename(pcc->cpu_model);
+    size_t typesize = object_type_get_instance_size(typename);
+    int i, j;
+    char *name;
+    XICSFabric *xi = XICS_FABRIC(qdev_get_machine());
+
+    name = g_strdup_printf("icp-%x", chip->chip_id);
+    memory_region_init(&chip->icp_mmio, OBJECT(chip), name, PNV_ICP_SIZE);
+    sysbus_init_mmio(SYS_BUS_DEVICE(chip), &chip->icp_mmio);
+    g_free(name);
+
+    sysbus_mmio_map(SYS_BUS_DEVICE(chip), 1, PNV_ICP_BASE(chip));
+
+    /* Map the ICP registers for each thread */
+    for (i = 0; i < chip->nr_cores; i++) {
+        PnvCore *pnv_core = PNV_CORE(chip->cores + i * typesize);
+        int core_hwid = CPU_CORE(pnv_core)->core_id;
+
+        for (j = 0; j < CPU_CORE(pnv_core)->nr_threads; j++) {
+            uint32_t pir = pcc->core_pir(chip, core_hwid) + j;
+            PnvICPState *icp = PNV_ICP(xics_icp_get(xi, pir));
+
+            memory_region_add_subregion(&chip->icp_mmio, pir << 12, &icp->mmio);
+        }
+    }
+
+    g_free(typename);
+}
+
 static void pnv_chip_realize(DeviceState *dev, Error **errp)
 {
     PnvChip *chip = PNV_CHIP(dev);
@@ -713,6 +786,14 @@ static void pnv_chip_realize(DeviceState *dev, Error **errp)
     object_property_set_bool(OBJECT(&chip->lpc), true, "realized",
                              &error_fatal);
     pnv_xscom_add_subregion(chip, PNV_XSCOM_LPC_BASE, &chip->lpc.xscom_regs);
+
+    /* Interrupt Management Area. This is the memory region holding
+     * all the Interrupt Control Presenter (ICP) registers */
+    pnv_chip_icp_realize(chip, &error);
+    if (error) {
+        error_propagate(errp, error);
+        return;
+    }
 }
 
 static Property pnv_chip_properties[] = {
diff --git a/include/hw/ppc/pnv.h b/include/hw/ppc/pnv.h
index 5693ba181d24..96231c1ff708 100644
--- a/include/hw/ppc/pnv.h
+++ b/include/hw/ppc/pnv.h
@@ -54,6 +54,7 @@ typedef struct PnvChip {
     MemoryRegion xscom_mmio;
     MemoryRegion xscom;
     AddressSpace xscom_as;
+    MemoryRegion icp_mmio;
 
     PnvLpcController lpc;
 } PnvChip;
@@ -136,4 +137,22 @@ typedef struct PnvMachineState {
 #define PNV_XSCOM_BASE(chip)                                            \
     (chip->xscom_base + ((uint64_t)(chip)->chip_id) * PNV_XSCOM_SIZE)
 
+/*
+ * XSCOM 0x20109CA defines the ICP BAR:
+ *
+ * 0:29   : bits 14 to 43 of address to define 1 MB region.
+ * 30     : 1 to enable ICP to receive loads/stores against its BAR region
+ * 31:63  : Constant 0
+ *
+ * Usually defined as :
+ *
+ *      0xffffe00200000000 -> 0x0003ffff80000000
+ *      0xffffe00600000000 -> 0x0003ffff80100000
+ *      0xffffe02200000000 -> 0x0003ffff80800000
+ *      0xffffe02600000000 -> 0x0003ffff80900000
+ */
+#define PNV_ICP_SIZE         0x0000000000100000ull
+#define PNV_ICP_BASE(chip)                                              \
+    (0x0003ffff80000000ull + (uint64_t) PNV_CHIP_INDEX(chip) * PNV_ICP_SIZE)
+
 #endif /* _PPC_PNV_H */
-- 
2.7.4