Re: [PATCH v1 02/23] pc/q35: Apply PCI bus BSEL property for Xen PCI device hotplug
On Thu, Jun 22, 2023 at 9:36 AM Igor Mammedov wrote:
>
> On Wed, 21 Jun 2023 13:24:42 -0400
> Joel Upham wrote:
>
> > On Wed, Jun 21, 2023 at 7:28 AM Igor Mammedov wrote:
> >
> > > On Tue, 20 Jun 2023 13:24:36 -0400
> > > Joel Upham wrote:
> > >
> > > > On Q35 we still need to assign BSEL property to bus(es) for PCI device
> > > > add/hotplug to work.
> > > > Extend acpi_set_pci_info() function to support Q35 as well. This patch
> > > adds new (trivial)
> > > > function find_q35() which returns root PCIBus object on Q35, in a way
> > > > similar to what find_i440fx does.
> > >
> > > I think patch is mostly obsolete, q35 ACPI PCI hotplug is supported in
> > > upstream QEMU.
> > >
> > > Also see comment below.
> > >
> > > I make use of the find_q35() function in later patches, but I agree now a
> > majority of this patch is a bit different.
>
> There is likely an existing alternative already. (probably introduced by ACPI
> PIC hotplug for q35)
There is a similar function acpi_get_i386_pci_host() in hw/i386/acpi-build.c
Best regards, Julia Suvorova.
> >
> > > >
> > > > Signed-off-by: Alexey Gerasimenko
> > > > Signed-off-by: Joel Upham
> > > > ---
> > > > hw/acpi/pcihp.c | 4 +++-
> > > > hw/pci-host/q35.c| 9 +
> > > > include/hw/i386/pc.h | 3 +++
> > > > 3 files changed, 15 insertions(+), 1 deletion(-)
> > > >
> > > > diff --git a/hw/acpi/pcihp.c b/hw/acpi/pcihp.c
> > > > index cdd6f775a1..f4e39d7a9c 100644
> > > > --- a/hw/acpi/pcihp.c
> > > > +++ b/hw/acpi/pcihp.c
> > > > @@ -40,6 +40,7 @@
> > > > #include "qapi/error.h"
> > > > #include "qom/qom-qobject.h"
> > > > #include "trace.h"
> > > > +#include "sysemu/xen.h"
> > > >
> > > > #define ACPI_PCIHP_SIZE 0x0018
> > > > #define PCI_UP_BASE 0x
> > > > @@ -84,7 +85,8 @@ static void *acpi_set_bsel(PCIBus *bus, void *opaque)
> > > > bool is_bridge = IS_PCI_BRIDGE(br);
> > > >
> > > > /* hotplugged bridges can't be described in ACPI ignore them */
> > > > -if (qbus_is_hotpluggable(BUS(bus))) {
> > >
> > > > +/* Xen requires hotplugging to the root device, even on the Q35
> > > chipset */
> > > pls explain what 'root device' is.
> > > Why can't you use root-ports for hotplug?
> > >
> > > Wording may have been incorrect. Root port is correct. This may not be
> > needed anymore,
> > and may have been left over for when I was debugging PCIe hotplugging
> > problems.
> > I will retest and fix patch once I know more. Xen expects the PCIe device
> > to be on the root port.
> >
> > I can move the function to a different patch that uses it.
> >
> > > > +if (qbus_is_hotpluggable(BUS(bus)) || xen_enabled()) {
> > > > if (!is_bridge || (!br->hotplugged &&
> > > info->has_bridge_hotplug)) {
> > > > bus_bsel = g_malloc(sizeof *bus_bsel);
> > > >
> > > > diff --git a/hw/pci-host/q35.c b/hw/pci-host/q35.c
> > > > index fd18920e7f..fe5fc0f47c 100644
> > > > --- a/hw/pci-host/q35.c
> > > > +++ b/hw/pci-host/q35.c
> > > > @@ -259,6 +259,15 @@ static void q35_host_initfn(Object *obj)
> > > > qdev_prop_allow_set_link_before_realize,
> > > 0);
> > > > }
> > > >
> > > > +PCIBus *find_q35(void)
> > > > +{
> > > > +PCIHostState *s = OBJECT_CHECK(PCIHostState,
> > > > + object_resolve_path("/machine/q35",
> > > NULL),
> > > > + TYPE_PCI_HOST_BRIDGE);
> > > > +return s ? s->bus : NULL;
> > > > +}
> > > > +
> > > > +
> > > > static const TypeInfo q35_host_info = {
> > > > .name = TYPE_Q35_HOST_DEVICE,
> > > > .parent = TYPE_PCIE_HOST_BRIDGE,
> > > > diff --git a/include/hw/i386/pc.h b/include/hw/i386/pc.h
> > > > index c661e9cc80..550f8fa221 100644
> > > > --- a/include/hw/i386/pc.h
> > > > +++ b/include/hw/i386/pc.h
> > > > @@ -196,6 +196,9 @@ void pc_madt_cpu_entry(int uid, const CPUArchIdList
> > > *apic_ids,
> > > > /* sgx.c */
> > > > void pc_machine_init_sgx_epc(PCMachineState *pcms);
> > > >
> > > > +/* q35.c */
> > > > +PCIBus *find_q35(void);
> > > > +
> > > > extern GlobalProperty pc_compat_8_0[];
> > > > extern const size_t pc_compat_8_0_len;
> > > >
> > >
> > >
>
>
Re: [PATCH v1 02/23] pc/q35: Apply PCI bus BSEL property for Xen PCI device hotplug
On Wed, 21 Jun 2023 13:24:42 -0400
Joel Upham wrote:
> On Wed, Jun 21, 2023 at 7:28 AM Igor Mammedov wrote:
>
> > On Tue, 20 Jun 2023 13:24:36 -0400
> > Joel Upham wrote:
> >
> > > On Q35 we still need to assign BSEL property to bus(es) for PCI device
> > > add/hotplug to work.
> > > Extend acpi_set_pci_info() function to support Q35 as well. This patch
> > adds new (trivial)
> > > function find_q35() which returns root PCIBus object on Q35, in a way
> > > similar to what find_i440fx does.
> >
> > I think patch is mostly obsolete, q35 ACPI PCI hotplug is supported in
> > upstream QEMU.
> >
> > Also see comment below.
> >
> > I make use of the find_q35() function in later patches, but I agree now a
> majority of this patch is a bit different.
There is likely an existing alternative already. (probably introduced by ACPI
PIC hotplug for q35)
>
> > >
> > > Signed-off-by: Alexey Gerasimenko
> > > Signed-off-by: Joel Upham
> > > ---
> > > hw/acpi/pcihp.c | 4 +++-
> > > hw/pci-host/q35.c| 9 +
> > > include/hw/i386/pc.h | 3 +++
> > > 3 files changed, 15 insertions(+), 1 deletion(-)
> > >
> > > diff --git a/hw/acpi/pcihp.c b/hw/acpi/pcihp.c
> > > index cdd6f775a1..f4e39d7a9c 100644
> > > --- a/hw/acpi/pcihp.c
> > > +++ b/hw/acpi/pcihp.c
> > > @@ -40,6 +40,7 @@
> > > #include "qapi/error.h"
> > > #include "qom/qom-qobject.h"
> > > #include "trace.h"
> > > +#include "sysemu/xen.h"
> > >
> > > #define ACPI_PCIHP_SIZE 0x0018
> > > #define PCI_UP_BASE 0x
> > > @@ -84,7 +85,8 @@ static void *acpi_set_bsel(PCIBus *bus, void *opaque)
> > > bool is_bridge = IS_PCI_BRIDGE(br);
> > >
> > > /* hotplugged bridges can't be described in ACPI ignore them */
> > > -if (qbus_is_hotpluggable(BUS(bus))) {
> >
> > > +/* Xen requires hotplugging to the root device, even on the Q35
> > chipset */
> > pls explain what 'root device' is.
> > Why can't you use root-ports for hotplug?
> >
> > Wording may have been incorrect. Root port is correct. This may not be
> needed anymore,
> and may have been left over for when I was debugging PCIe hotplugging
> problems.
> I will retest and fix patch once I know more. Xen expects the PCIe device
> to be on the root port.
>
> I can move the function to a different patch that uses it.
>
> > > +if (qbus_is_hotpluggable(BUS(bus)) || xen_enabled()) {
> > > if (!is_bridge || (!br->hotplugged &&
> > info->has_bridge_hotplug)) {
> > > bus_bsel = g_malloc(sizeof *bus_bsel);
> > >
> > > diff --git a/hw/pci-host/q35.c b/hw/pci-host/q35.c
> > > index fd18920e7f..fe5fc0f47c 100644
> > > --- a/hw/pci-host/q35.c
> > > +++ b/hw/pci-host/q35.c
> > > @@ -259,6 +259,15 @@ static void q35_host_initfn(Object *obj)
> > > qdev_prop_allow_set_link_before_realize,
> > 0);
> > > }
> > >
> > > +PCIBus *find_q35(void)
> > > +{
> > > +PCIHostState *s = OBJECT_CHECK(PCIHostState,
> > > + object_resolve_path("/machine/q35",
> > NULL),
> > > + TYPE_PCI_HOST_BRIDGE);
> > > +return s ? s->bus : NULL;
> > > +}
> > > +
> > > +
> > > static const TypeInfo q35_host_info = {
> > > .name = TYPE_Q35_HOST_DEVICE,
> > > .parent = TYPE_PCIE_HOST_BRIDGE,
> > > diff --git a/include/hw/i386/pc.h b/include/hw/i386/pc.h
> > > index c661e9cc80..550f8fa221 100644
> > > --- a/include/hw/i386/pc.h
> > > +++ b/include/hw/i386/pc.h
> > > @@ -196,6 +196,9 @@ void pc_madt_cpu_entry(int uid, const CPUArchIdList
> > *apic_ids,
> > > /* sgx.c */
> > > void pc_machine_init_sgx_epc(PCMachineState *pcms);
> > >
> > > +/* q35.c */
> > > +PCIBus *find_q35(void);
> > > +
> > > extern GlobalProperty pc_compat_8_0[];
> > > extern const size_t pc_compat_8_0_len;
> > >
> >
> >
Re: [PATCH v1 02/23] pc/q35: Apply PCI bus BSEL property for Xen PCI device hotplug
On Wed, Jun 21, 2023 at 7:28 AM Igor Mammedov wrote:
> On Tue, 20 Jun 2023 13:24:36 -0400
> Joel Upham wrote:
>
> > On Q35 we still need to assign BSEL property to bus(es) for PCI device
> > add/hotplug to work.
> > Extend acpi_set_pci_info() function to support Q35 as well. This patch
> adds new (trivial)
> > function find_q35() which returns root PCIBus object on Q35, in a way
> > similar to what find_i440fx does.
>
> I think patch is mostly obsolete, q35 ACPI PCI hotplug is supported in
> upstream QEMU.
>
> Also see comment below.
>
> I make use of the find_q35() function in later patches, but I agree now a
majority of this patch is a bit different.
> >
> > Signed-off-by: Alexey Gerasimenko
> > Signed-off-by: Joel Upham
> > ---
> > hw/acpi/pcihp.c | 4 +++-
> > hw/pci-host/q35.c| 9 +
> > include/hw/i386/pc.h | 3 +++
> > 3 files changed, 15 insertions(+), 1 deletion(-)
> >
> > diff --git a/hw/acpi/pcihp.c b/hw/acpi/pcihp.c
> > index cdd6f775a1..f4e39d7a9c 100644
> > --- a/hw/acpi/pcihp.c
> > +++ b/hw/acpi/pcihp.c
> > @@ -40,6 +40,7 @@
> > #include "qapi/error.h"
> > #include "qom/qom-qobject.h"
> > #include "trace.h"
> > +#include "sysemu/xen.h"
> >
> > #define ACPI_PCIHP_SIZE 0x0018
> > #define PCI_UP_BASE 0x
> > @@ -84,7 +85,8 @@ static void *acpi_set_bsel(PCIBus *bus, void *opaque)
> > bool is_bridge = IS_PCI_BRIDGE(br);
> >
> > /* hotplugged bridges can't be described in ACPI ignore them */
> > -if (qbus_is_hotpluggable(BUS(bus))) {
>
> > +/* Xen requires hotplugging to the root device, even on the Q35
> chipset */
> pls explain what 'root device' is.
> Why can't you use root-ports for hotplug?
>
> Wording may have been incorrect. Root port is correct. This may not be
needed anymore,
and may have been left over for when I was debugging PCIe hotplugging
problems.
I will retest and fix patch once I know more. Xen expects the PCIe device
to be on the root port.
I can move the function to a different patch that uses it.
> > +if (qbus_is_hotpluggable(BUS(bus)) || xen_enabled()) {
> > if (!is_bridge || (!br->hotplugged &&
> info->has_bridge_hotplug)) {
> > bus_bsel = g_malloc(sizeof *bus_bsel);
> >
> > diff --git a/hw/pci-host/q35.c b/hw/pci-host/q35.c
> > index fd18920e7f..fe5fc0f47c 100644
> > --- a/hw/pci-host/q35.c
> > +++ b/hw/pci-host/q35.c
> > @@ -259,6 +259,15 @@ static void q35_host_initfn(Object *obj)
> > qdev_prop_allow_set_link_before_realize,
> 0);
> > }
> >
> > +PCIBus *find_q35(void)
> > +{
> > +PCIHostState *s = OBJECT_CHECK(PCIHostState,
> > + object_resolve_path("/machine/q35",
> NULL),
> > + TYPE_PCI_HOST_BRIDGE);
> > +return s ? s->bus : NULL;
> > +}
> > +
> > +
> > static const TypeInfo q35_host_info = {
> > .name = TYPE_Q35_HOST_DEVICE,
> > .parent = TYPE_PCIE_HOST_BRIDGE,
> > diff --git a/include/hw/i386/pc.h b/include/hw/i386/pc.h
> > index c661e9cc80..550f8fa221 100644
> > --- a/include/hw/i386/pc.h
> > +++ b/include/hw/i386/pc.h
> > @@ -196,6 +196,9 @@ void pc_madt_cpu_entry(int uid, const CPUArchIdList
> *apic_ids,
> > /* sgx.c */
> > void pc_machine_init_sgx_epc(PCMachineState *pcms);
> >
> > +/* q35.c */
> > +PCIBus *find_q35(void);
> > +
> > extern GlobalProperty pc_compat_8_0[];
> > extern const size_t pc_compat_8_0_len;
> >
>
>
Re: [PATCH v1 02/23] pc/q35: Apply PCI bus BSEL property for Xen PCI device hotplug
On Tue, 20 Jun 2023 13:24:36 -0400
Joel Upham wrote:
> On Q35 we still need to assign BSEL property to bus(es) for PCI device
> add/hotplug to work.
> Extend acpi_set_pci_info() function to support Q35 as well. This patch adds
> new (trivial)
> function find_q35() which returns root PCIBus object on Q35, in a way
> similar to what find_i440fx does.
I think patch is mostly obsolete, q35 ACPI PCI hotplug is supported in upstream
QEMU.
Also see comment below.
>
> Signed-off-by: Alexey Gerasimenko
> Signed-off-by: Joel Upham
> ---
> hw/acpi/pcihp.c | 4 +++-
> hw/pci-host/q35.c| 9 +
> include/hw/i386/pc.h | 3 +++
> 3 files changed, 15 insertions(+), 1 deletion(-)
>
> diff --git a/hw/acpi/pcihp.c b/hw/acpi/pcihp.c
> index cdd6f775a1..f4e39d7a9c 100644
> --- a/hw/acpi/pcihp.c
> +++ b/hw/acpi/pcihp.c
> @@ -40,6 +40,7 @@
> #include "qapi/error.h"
> #include "qom/qom-qobject.h"
> #include "trace.h"
> +#include "sysemu/xen.h"
>
> #define ACPI_PCIHP_SIZE 0x0018
> #define PCI_UP_BASE 0x
> @@ -84,7 +85,8 @@ static void *acpi_set_bsel(PCIBus *bus, void *opaque)
> bool is_bridge = IS_PCI_BRIDGE(br);
>
> /* hotplugged bridges can't be described in ACPI ignore them */
> -if (qbus_is_hotpluggable(BUS(bus))) {
> +/* Xen requires hotplugging to the root device, even on the Q35 chipset
> */
pls explain what 'root device' is.
Why can't you use root-ports for hotplug?
> +if (qbus_is_hotpluggable(BUS(bus)) || xen_enabled()) {
> if (!is_bridge || (!br->hotplugged && info->has_bridge_hotplug)) {
> bus_bsel = g_malloc(sizeof *bus_bsel);
>
> diff --git a/hw/pci-host/q35.c b/hw/pci-host/q35.c
> index fd18920e7f..fe5fc0f47c 100644
> --- a/hw/pci-host/q35.c
> +++ b/hw/pci-host/q35.c
> @@ -259,6 +259,15 @@ static void q35_host_initfn(Object *obj)
> qdev_prop_allow_set_link_before_realize, 0);
> }
>
> +PCIBus *find_q35(void)
> +{
> +PCIHostState *s = OBJECT_CHECK(PCIHostState,
> + object_resolve_path("/machine/q35", NULL),
> + TYPE_PCI_HOST_BRIDGE);
> +return s ? s->bus : NULL;
> +}
> +
> +
> static const TypeInfo q35_host_info = {
> .name = TYPE_Q35_HOST_DEVICE,
> .parent = TYPE_PCIE_HOST_BRIDGE,
> diff --git a/include/hw/i386/pc.h b/include/hw/i386/pc.h
> index c661e9cc80..550f8fa221 100644
> --- a/include/hw/i386/pc.h
> +++ b/include/hw/i386/pc.h
> @@ -196,6 +196,9 @@ void pc_madt_cpu_entry(int uid, const CPUArchIdList
> *apic_ids,
> /* sgx.c */
> void pc_machine_init_sgx_epc(PCMachineState *pcms);
>
> +/* q35.c */
> +PCIBus *find_q35(void);
> +
> extern GlobalProperty pc_compat_8_0[];
> extern const size_t pc_compat_8_0_len;
>
[PATCH v1 02/23] pc/q35: Apply PCI bus BSEL property for Xen PCI device hotplug
On Q35 we still need to assign BSEL property to bus(es) for PCI device
add/hotplug to work.
Extend acpi_set_pci_info() function to support Q35 as well. This patch adds new
(trivial)
function find_q35() which returns root PCIBus object on Q35, in a way
similar to what find_i440fx does.
Signed-off-by: Alexey Gerasimenko
Signed-off-by: Joel Upham
---
hw/acpi/pcihp.c | 4 +++-
hw/pci-host/q35.c| 9 +
include/hw/i386/pc.h | 3 +++
3 files changed, 15 insertions(+), 1 deletion(-)
diff --git a/hw/acpi/pcihp.c b/hw/acpi/pcihp.c
index cdd6f775a1..f4e39d7a9c 100644
--- a/hw/acpi/pcihp.c
+++ b/hw/acpi/pcihp.c
@@ -40,6 +40,7 @@
#include "qapi/error.h"
#include "qom/qom-qobject.h"
#include "trace.h"
+#include "sysemu/xen.h"
#define ACPI_PCIHP_SIZE 0x0018
#define PCI_UP_BASE 0x
@@ -84,7 +85,8 @@ static void *acpi_set_bsel(PCIBus *bus, void *opaque)
bool is_bridge = IS_PCI_BRIDGE(br);
/* hotplugged bridges can't be described in ACPI ignore them */
-if (qbus_is_hotpluggable(BUS(bus))) {
+/* Xen requires hotplugging to the root device, even on the Q35 chipset */
+if (qbus_is_hotpluggable(BUS(bus)) || xen_enabled()) {
if (!is_bridge || (!br->hotplugged && info->has_bridge_hotplug)) {
bus_bsel = g_malloc(sizeof *bus_bsel);
diff --git a/hw/pci-host/q35.c b/hw/pci-host/q35.c
index fd18920e7f..fe5fc0f47c 100644
--- a/hw/pci-host/q35.c
+++ b/hw/pci-host/q35.c
@@ -259,6 +259,15 @@ static void q35_host_initfn(Object *obj)
qdev_prop_allow_set_link_before_realize, 0);
}
+PCIBus *find_q35(void)
+{
+PCIHostState *s = OBJECT_CHECK(PCIHostState,
+ object_resolve_path("/machine/q35", NULL),
+ TYPE_PCI_HOST_BRIDGE);
+return s ? s->bus : NULL;
+}
+
+
static const TypeInfo q35_host_info = {
.name = TYPE_Q35_HOST_DEVICE,
.parent = TYPE_PCIE_HOST_BRIDGE,
diff --git a/include/hw/i386/pc.h b/include/hw/i386/pc.h
index c661e9cc80..550f8fa221 100644
--- a/include/hw/i386/pc.h
+++ b/include/hw/i386/pc.h
@@ -196,6 +196,9 @@ void pc_madt_cpu_entry(int uid, const CPUArchIdList
*apic_ids,
/* sgx.c */
void pc_machine_init_sgx_epc(PCMachineState *pcms);
+/* q35.c */
+PCIBus *find_q35(void);
+
extern GlobalProperty pc_compat_8_0[];
extern const size_t pc_compat_8_0_len;
--
2.34.1
