Re: [Qemu-devel] [PATCH] piix: do not reset APIC base address (0x80) on piix4_reset.

["Michael S. Tsirkin" <mst@redhat.com>]

On Thu, Dec 19, 2013 at 11:49:21AM +0200, Marcel Apfelbaum wrote:
> > > Basically something like the below (warning: completely untested,
> > > sorry).
> > I tested and it works fine for both windows and linux guests!
> Actually it doesn't work :(
> I was testing a "working hack", not the master branch.
> I still think it is the right direction.
> 
> Thanks,
> Marcel

Actually in hindsight there's no chance this can work:
it assumes device memory is mapped already.
I really meant just calling pci_init_device.
Maybe something like the below, or maybe we
even need a separate table for resume callbacks.

---

diff --git a/src/hw/pci.h b/src/hw/pci.h
index 9c7351d..a64f7c5 100644
--- a/src/hw/pci.h
+++ b/src/hw/pci.h
@@ -66,6 +66,7 @@ extern u64 pcimem64_start, pcimem64_end;
 extern struct hlist_head PCIDevices;
 extern int MaxPCIBus;
 int pci_probe_host(void);
+void pci_probe_device(int bdf, struct pci_device *dev);
 void pci_probe_devices(void);
 static inline u32 pci_classprog(struct pci_device *pci) {
     return (pci->class << 8) | pci->prog_if;
diff --git a/src/util.h b/src/util.h
index e6a6cb5..3a24dba 100644
--- a/src/util.h
+++ b/src/util.h
@@ -28,6 +28,7 @@ void boot_add_cbfs(void *data, const char *desc, int prio);
 void interactive_bootmenu(void);
 void bcv_prepboot(void);
 struct pci_device;
+void pci_bios_resume_device(struct pci_device *pci);
 int bootprio_find_pci_device(struct pci_device *pci);
 int bootprio_find_scsi_device(struct pci_device *pci, int target, int lun);
 int bootprio_find_ata_device(struct pci_device *pci, int chanid, int slave);
diff --git a/src/fw/pciinit.c b/src/fw/pciinit.c
index 34279a4..a4cedfb 100644
--- a/src/fw/pciinit.c
+++ b/src/fw/pciinit.c
@@ -293,6 +293,11 @@ static const struct pci_device_id pci_device_tbl[] = {
     PCI_DEVICE_END,
 };
 
+void pci_bios_resume_device(struct pci_device *pci)
+{
+    pci_init_device(pci_device_tbl, pci, NULL);
+}
+
 static void pci_bios_init_device(struct pci_device *pci)
 {
     u16 bdf = pci->bdf;
diff --git a/src/hw/pci.c b/src/hw/pci.c
index 6c9aa81..c2873c3 100644
--- a/src/hw/pci.c
+++ b/src/hw/pci.c
@@ -105,6 +105,24 @@ pci_probe_host(void)
     return 0;
 }
 
+void
+pci_probe_device(int bdf, struct pci_device *dev)
+{
+    dev->bdf = bdf;
+    u32 vendev = pci_config_readl(bdf, PCI_VENDOR_ID);
+    dev->vendor = vendev & 0xffff;
+    dev->device = vendev >> 16;
+    u32 classrev = pci_config_readl(bdf, PCI_CLASS_REVISION);
+    dev->class = classrev >> 16;
+    dev->prog_if = classrev >> 8;
+    dev->revision = classrev & 0xff;
+    dev->header_type = pci_config_readb(bdf, PCI_HEADER_TYPE);
+    u8 v = dev->header_type & 0x7f;
+    if (v == PCI_HEADER_TYPE_BRIDGE || v == PCI_HEADER_TYPE_CARDBUS) {
+        u8 secbus = pci_config_readb(bdf, PCI_SECONDARY_BUS);
+        dev->secondary_bus = secbus;
+    }
+}
 // Find all PCI devices and populate PCIDevices linked list.
 void
 pci_probe_devices(void)
@@ -145,21 +163,12 @@ pci_probe_devices(void)
             }
 
             // Populate pci_device info.
-            dev->bdf = bdf;
+            pci_probe_device(bdf, dev);
             dev->parent = parent;
             dev->rootbus = rootbus;
-            u32 vendev = pci_config_readl(bdf, PCI_VENDOR_ID);
-            dev->vendor = vendev & 0xffff;
-            dev->device = vendev >> 16;
-            u32 classrev = pci_config_readl(bdf, PCI_CLASS_REVISION);
-            dev->class = classrev >> 16;
-            dev->prog_if = classrev >> 8;
-            dev->revision = classrev & 0xff;
-            dev->header_type = pci_config_readb(bdf, PCI_HEADER_TYPE);
             u8 v = dev->header_type & 0x7f;
             if (v == PCI_HEADER_TYPE_BRIDGE || v == PCI_HEADER_TYPE_CARDBUS) {
-                u8 secbus = pci_config_readb(bdf, PCI_SECONDARY_BUS);
-                dev->secondary_bus = secbus;
+                u8 secbus = dev->secondary_bus;
                 if (secbus > bus && !busdevs[secbus])
                     busdevs[secbus] = dev;
                 if (secbus > MaxPCIBus)
diff --git a/src/resume.c b/src/resume.c
index fc2fee9..9aac853 100644
--- a/src/resume.c
+++ b/src/resume.c
@@ -101,6 +101,14 @@ s3_resume(void)
     pic_setup();
     smm_setup();
 
+    int bdf;
+    foreachbdf(bdf, 0) {
+        // Create new pci_device struct and add to list.
+        struct pci_device pci;
+        pci_probe_device(bdf, &pci);
+        pci_bios_resume_device(&pci);
+    }
+
     s3_resume_vga();
 
     make_bios_readonly();