[Qemu-devel] [RFC PATCH v4 15/30] q35: Add i440fx dram controller initialization

[Vasilis Liaskovitis]

Create memory buses and introduce function to adjust memory map for
hotplug-able dimms.

Signed-off-by: Vasilis Liaskovitis <vasilis.liaskovi...@profitbricks.com>
---
 hw/pc_q35.c |    1 +
 hw/q35.c    |   27 +++++++++++++++++++++++++++
 hw/q35.h    |    5 +++++
 3 files changed, 33 insertions(+), 0 deletions(-)

diff --git a/hw/pc_q35.c b/hw/pc_q35.c
index 3429a9a..e6375bf 100644
--- a/hw/pc_q35.c
+++ b/hw/pc_q35.c
@@ -41,6 +41,7 @@
 #include "hw/ide/pci.h"
 #include "hw/ide/ahci.h"
 #include "hw/usb.h"
+#include "fw_cfg.h"
 
 /* ICH9 AHCI has 6 ports */
 #define MAX_SATA_PORTS     6
diff --git a/hw/q35.c b/hw/q35.c
index efebc27..cc27d72 100644
--- a/hw/q35.c
+++ b/hw/q35.c
@@ -236,12 +236,39 @@ static void mch_reset(DeviceState *qdev)
     mch_update(mch);
 }
 
+static hwaddr mch_dimm_offset(DeviceState *dev, uint64_t size)
+{
+    MCHPCIState *d = MCH_PCI_DEVICE(dev);
+    hwaddr ret;
+
+    /* if dimm fits before pci hole, append it normally */
+    if (d->below_4g_mem_size + size <= MCH_HOST_BRIDGE_PCIEXBAR_DEFAULT) {
+        ret = d->below_4g_mem_size;
+        d->below_4g_mem_size += size;
+    }
+    /* otherwise place it above 4GB */
+    else {
+        ret = 0x100000000LL + d->above_4g_mem_size;
+        d->above_4g_mem_size += size;
+    }
+
+    return ret;
+}
+
 static int mch_init(PCIDevice *d)
 {
     int i;
     hwaddr pci_hole64_size;
     MCHPCIState *mch = MCH_PCI_DEVICE(d);
 
+    /* Initialize 2 GMC DRAM channels x 4 DRAM ranks each */
+    mch->dram_channel[0] = dimm_bus_create(OBJECT(d), "membus.0", 4,
+            mch_dimm_offset);
+    mch->dram_channel[1] = dimm_bus_create(OBJECT(d), "membus.1", 4,
+            mch_dimm_offset);
+    /* Initialize paravirtual memory bus */
+    mch->pv_dram_channel = dimm_bus_create(OBJECT(d), "membus.pv", 0,
+            mch_dimm_offset);
     /* setup pci memory regions */
     memory_region_init_alias(&mch->pci_hole, "pci-hole",
                              mch->pci_address_space,
diff --git a/hw/q35.h b/hw/q35.h
index e34f7c1..bf76dc8 100644
--- a/hw/q35.h
+++ b/hw/q35.h
@@ -34,6 +34,7 @@
 #include "acpi.h"
 #include "acpi_ich9.h"
 #include "pam.h"
+#include "dimm.h"
 
 #define TYPE_Q35_HOST_DEVICE "q35-pcihost"
 #define Q35_HOST_DEVICE(obj) \
@@ -56,6 +57,10 @@ typedef struct MCHPCIState {
     uint8_t smm_enabled;
     ram_addr_t below_4g_mem_size;
     ram_addr_t above_4g_mem_size;
+    /* GMCH allows for 2 DRAM channels x 4 DRAM ranks each */
+    DimmBus * dram_channel[2];
+    /* paravirtual memory bus */
+    DimmBus *pv_dram_channel;
 } MCHPCIState;
 
 typedef struct Q35PCIHost {
-- 
1.7.9