[PATCH 1/2] PCI: hv: Make the code arch neutral

From: Sunil Muthuswamy
Date: Mon Sep 13 2021 - 13:36:54 EST


This patch makes the Hyper-V vPCI code architectural neutral by
moving the architectural dependent pieces into arch specific
code. This allows for the implementation of Hyper-V vPCI for
other architecture such as ARM64.

There are no functional changes expected from this patch.

Signed-off-by: Sunil Muthuswamy <sunilmut@xxxxxxxxxxxxx>
---
arch/x86/include/asm/hyperv-tlfs.h | 33 ++++++++++++++++++++++
arch/x86/include/asm/mshyperv.h | 25 ++++++++++++++++
drivers/pci/controller/pci-hyperv.c | 44 +++++++++++++++++++----------
include/asm-generic/hyperv-tlfs.h | 33 ----------------------
4 files changed, 87 insertions(+), 48 deletions(-)

diff --git a/arch/x86/include/asm/hyperv-tlfs.h b/arch/x86/include/asm/hyperv-tlfs.h
index 2322d6bd5883..fdf3d28fbdd5 100644
--- a/arch/x86/include/asm/hyperv-tlfs.h
+++ b/arch/x86/include/asm/hyperv-tlfs.h
@@ -585,6 +585,39 @@ enum hv_interrupt_type {
HV_X64_INTERRUPT_TYPE_MAXIMUM = 0x000A,
};

+union hv_msi_address_register {
+ u32 as_uint32;
+ struct {
+ u32 reserved1:2;
+ u32 destination_mode:1;
+ u32 redirection_hint:1;
+ u32 reserved2:8;
+ u32 destination_id:8;
+ u32 msi_base:12;
+ };
+} __packed;
+
+union hv_msi_data_register {
+ u32 as_uint32;
+ struct {
+ u32 vector:8;
+ u32 delivery_mode:3;
+ u32 reserved1:3;
+ u32 level_assert:1;
+ u32 trigger_mode:1;
+ u32 reserved2:16;
+ };
+} __packed;
+
+/* HvRetargetDeviceInterrupt hypercall */
+union hv_msi_entry {
+ u64 as_uint64;
+ struct {
+ union hv_msi_address_register address;
+ union hv_msi_data_register data;
+ } __packed;
+};
+
#include <asm-generic/hyperv-tlfs.h>

#endif
diff --git a/arch/x86/include/asm/mshyperv.h b/arch/x86/include/asm/mshyperv.h
index adccbc209169..9c53dfef360c 100644
--- a/arch/x86/include/asm/mshyperv.h
+++ b/arch/x86/include/asm/mshyperv.h
@@ -10,6 +10,7 @@
#include <asm/nospec-branch.h>
#include <asm/paravirt.h>
#include <asm/mshyperv.h>
+#include <asm/msi.h>

typedef int (*hyperv_fill_flush_list_func)(
struct hv_guest_mapping_flush_list *flush,
@@ -168,6 +169,30 @@ int hyperv_fill_flush_guest_mapping_list(
struct hv_guest_mapping_flush_list *flush,
u64 start_gfn, u64 end_gfn);

+#define hv_msi_handler handle_edge_irq
+#define hv_msi_handler_name "edge"
+#define hv_msi_prepare pci_msi_prepare
+#define hv_msi_irq_delivery_mode APIC_DELIVERY_MODE_FIXED
+
+static inline struct irq_domain *hv_msi_parent_vector_domain(void)
+{
+ return x86_vector_domain;
+}
+
+static inline unsigned int hv_msi_get_int_vector(struct irq_data *data)
+{
+ struct irq_cfg *cfg = irqd_cfg(data);
+
+ return cfg->vector;
+}
+
+static inline int hv_pci_arch_init(void)
+{
+ return 0;
+}
+
+static inline void hv_pci_arch_free(void) {}
+
#ifdef CONFIG_X86_64
void hv_apic_init(void);
void __init hv_init_spinlocks(void);
diff --git a/drivers/pci/controller/pci-hyperv.c b/drivers/pci/controller/pci-hyperv.c
index 62dbe98d1fe1..b7213b57b4ec 100644
--- a/drivers/pci/controller/pci-hyperv.c
+++ b/drivers/pci/controller/pci-hyperv.c
@@ -44,8 +44,8 @@
#include <linux/delay.h>
#include <linux/semaphore.h>
#include <linux/irqdomain.h>
-#include <asm/irqdomain.h>
-#include <asm/apic.h>
+//#include <asm/irqdomain.h>
+//#include <asm/apic.h>
#include <linux/irq.h>
#include <linux/msi.h>
#include <linux/hyperv.h>
@@ -1192,7 +1192,6 @@ static void hv_irq_mask(struct irq_data *data)
static void hv_irq_unmask(struct irq_data *data)
{
struct msi_desc *msi_desc = irq_data_get_msi_desc(data);
- struct irq_cfg *cfg = irqd_cfg(data);
struct hv_retarget_device_interrupt *params;
struct hv_pcibus_device *hbus;
struct cpumask *dest;
@@ -1221,11 +1220,12 @@ static void hv_irq_unmask(struct irq_data *data)
(hbus->hdev->dev_instance.b[7] << 8) |
(hbus->hdev->dev_instance.b[6] & 0xf8) |
PCI_FUNC(pdev->devfn);
- params->int_target.vector = cfg->vector;
+ params->int_target.vector = hv_msi_get_int_vector(data);

/*
- * Honoring apic->delivery_mode set to APIC_DELIVERY_MODE_FIXED by
- * setting the HV_DEVICE_INTERRUPT_TARGET_MULTICAST flag results in a
+ * For x64, honoring apic->delivery_mode set to
+ * APIC_DELIVERY_MODE_FIXED by setting the
+ * HV_DEVICE_INTERRUPT_TARGET_MULTICAST flag results in a
* spurious interrupt storm. Not doing so does not seem to have a
* negative effect (yet?).
*/
@@ -1322,7 +1322,7 @@ static u32 hv_compose_msi_req_v1(
int_pkt->wslot.slot = slot;
int_pkt->int_desc.vector = vector;
int_pkt->int_desc.vector_count = 1;
- int_pkt->int_desc.delivery_mode = APIC_DELIVERY_MODE_FIXED;
+ int_pkt->int_desc.delivery_mode = hv_msi_irq_delivery_mode;

/*
* Create MSI w/ dummy vCPU set, overwritten by subsequent retarget in
@@ -1343,7 +1343,7 @@ static u32 hv_compose_msi_req_v2(
int_pkt->wslot.slot = slot;
int_pkt->int_desc.vector = vector;
int_pkt->int_desc.vector_count = 1;
- int_pkt->int_desc.delivery_mode = APIC_DELIVERY_MODE_FIXED;
+ int_pkt->int_desc.delivery_mode = hv_msi_irq_delivery_mode;

/*
* Create MSI w/ dummy vCPU set targeting just one vCPU, overwritten
@@ -1370,7 +1370,6 @@ static u32 hv_compose_msi_req_v2(
*/
static void hv_compose_msi_msg(struct irq_data *data, struct msi_msg *msg)
{
- struct irq_cfg *cfg = irqd_cfg(data);
struct hv_pcibus_device *hbus;
struct vmbus_channel *channel;
struct hv_pci_dev *hpdev;
@@ -1420,7 +1419,7 @@ static void hv_compose_msi_msg(struct irq_data *data, struct msi_msg *msg)
size = hv_compose_msi_req_v1(&ctxt.int_pkts.v1,
dest,
hpdev->desc.win_slot.slot,
- cfg->vector);
+ hv_msi_get_int_vector(data));
break;

case PCI_PROTOCOL_VERSION_1_2:
@@ -1428,7 +1427,7 @@ static void hv_compose_msi_msg(struct irq_data *data, struct msi_msg *msg)
size = hv_compose_msi_req_v2(&ctxt.int_pkts.v2,
dest,
hpdev->desc.win_slot.slot,
- cfg->vector);
+ hv_msi_get_int_vector(data));
break;

default:
@@ -1544,7 +1543,7 @@ static struct irq_chip hv_msi_irq_chip = {
};

static struct msi_domain_ops hv_msi_ops = {
- .msi_prepare = pci_msi_prepare,
+ .msi_prepare = hv_msi_prepare,
.msi_free = hv_msi_free,
};

@@ -1563,17 +1562,26 @@ static struct msi_domain_ops hv_msi_ops = {
*/
static int hv_pcie_init_irq_domain(struct hv_pcibus_device *hbus)
{
+ struct irq_domain *parent_domain;
+
+ parent_domain = hv_msi_parent_vector_domain();
+ if (!parent_domain) {
+ dev_err(&hbus->hdev->device,
+ "Failed to get parent MSI domain\n");
+ return -ENODEV;
+ }
+
hbus->msi_info.chip = &hv_msi_irq_chip;
hbus->msi_info.ops = &hv_msi_ops;
hbus->msi_info.flags = (MSI_FLAG_USE_DEF_DOM_OPS |
MSI_FLAG_USE_DEF_CHIP_OPS | MSI_FLAG_MULTI_PCI_MSI |
MSI_FLAG_PCI_MSIX);
- hbus->msi_info.handler = handle_edge_irq;
- hbus->msi_info.handler_name = "edge";
+ hbus->msi_info.handler = hv_msi_handler;
+ hbus->msi_info.handler_name = hv_msi_handler_name;
hbus->msi_info.data = hbus;
hbus->irq_domain = pci_msi_create_irq_domain(hbus->fwnode,
&hbus->msi_info,
- x86_vector_domain);
+ parent_domain);
if (!hbus->irq_domain) {
dev_err(&hbus->hdev->device,
"Failed to build an MSI IRQ domain\n");
@@ -3478,9 +3486,15 @@ static void __exit exit_hv_pci_drv(void)

static int __init init_hv_pci_drv(void)
{
+ int ret;
+
if (!hv_is_hyperv_initialized())
return -ENODEV;

+ ret = hv_pci_arch_init();
+ if (ret)
+ return ret;
+
/* Set the invalid domain number's bit, so it will not be used */
set_bit(HVPCI_DOM_INVALID, hvpci_dom_map);

diff --git a/include/asm-generic/hyperv-tlfs.h b/include/asm-generic/hyperv-tlfs.h
index 56348a541c50..45cc0c3b8ed7 100644
--- a/include/asm-generic/hyperv-tlfs.h
+++ b/include/asm-generic/hyperv-tlfs.h
@@ -539,39 +539,6 @@ enum hv_interrupt_source {
HV_INTERRUPT_SOURCE_IOAPIC,
};

-union hv_msi_address_register {
- u32 as_uint32;
- struct {
- u32 reserved1:2;
- u32 destination_mode:1;
- u32 redirection_hint:1;
- u32 reserved2:8;
- u32 destination_id:8;
- u32 msi_base:12;
- };
-} __packed;
-
-union hv_msi_data_register {
- u32 as_uint32;
- struct {
- u32 vector:8;
- u32 delivery_mode:3;
- u32 reserved1:3;
- u32 level_assert:1;
- u32 trigger_mode:1;
- u32 reserved2:16;
- };
-} __packed;
-
-/* HvRetargetDeviceInterrupt hypercall */
-union hv_msi_entry {
- u64 as_uint64;
- struct {
- union hv_msi_address_register address;
- union hv_msi_data_register data;
- } __packed;
-};
-
union hv_ioapic_rte {
u64 as_uint64;

--
2.25.1