[PATCH 2/2] xen/arm: Make HAS_PCI compilable on ARM by adding place-holder code

[Manish Jaggi <mjaggi@caviumnetworks.com>]

Add ARM PCI Support
---------------
a) Place holder functions are added for pci_conf_read/write calls.
b) Macros dev_is_pci, pci_to_dev are implemented in
drivers/passthrough/pci/arm code

Signed-off-by: Manish Jaggi <manish.jaggi@caviumnetworks.com>
---
  xen/arch/arm/Makefile                |    1 +
  xen/arch/arm/pci.c                   |   60 +++++++++++++++++++++++
  xen/drivers/passthrough/arm/Makefile |    1 +
  xen/drivers/passthrough/arm/pci.c    |   88 ++++++++++++++++++++++++++++++++++
  xen/drivers/passthrough/arm/smmu.c   |    1 -
  xen/drivers/passthrough/pci.c        |    9 ++--
  xen/include/asm-arm/device.h         |   33 +++++++++----
  xen/include/asm-arm/domain.h         |    3 ++
  xen/include/asm-arm/pci.h            |    7 +--
  9 files changed, 186 insertions(+), 17 deletions(-)

diff --git a/xen/arch/arm/Makefile b/xen/arch/arm/Makefile
index 935999e..aaf5d88 100644
--- a/xen/arch/arm/Makefile
+++ b/xen/arch/arm/Makefile
@@ -39,6 +39,7 @@ obj-y += device.o
  obj-y += decode.o
  obj-y += processor.o
  obj-y += smc.o
+obj-$(HAS_PCI) += pci.o
  
  #obj-bin-y += ....o
  
diff --git a/xen/arch/arm/pci.c b/xen/arch/arm/pci.c
new file mode 100644
index 0000000..9438f41
--- /dev/null
+++ b/xen/arch/arm/pci.c
@@ -0,0 +1,60 @@
+#include <xen/pci.h>
+
+void _pci_conf_write(
+    uint32_t seg, uint32_t bus, uint32_t dev, uint32_t func,
+    uint32_t reg, uint32_t data, int bytes)
+{
+}
+
+uint32_t _pci_conf_read(
+    uint32_t seg, uint32_t bus, uint32_t dev, uint32_t func,
+    uint32_t reg, int bytes)
+{
+    return 0;
+}
+
+uint8_t pci_conf_read8(
+    uint32_t seg, uint32_t bus, uint32_t dev, uint32_t func,
+    uint32_t reg)
+{
+    return (uint8_t)_pci_conf_read(seg, bus, dev, func, reg, 1);
+}
+
+uint16_t pci_conf_read16(
+    uint32_t seg, uint32_t bus, uint32_t dev, uint32_t func,
+    uint32_t reg)
+{
+    return (uint8_t)_pci_conf_read(seg, bus, dev, func, reg, 2);
+}
+
+uint32_t pci_conf_read32(
+    uint32_t seg, uint32_t bus, uint32_t dev, uint32_t func,
+    uint32_t reg)
+{
+    return (uint8_t)_pci_conf_read(seg, bus, dev, func, reg, 4);
+}
+
+void pci_conf_write8(
+    uint32_t seg, uint32_t bus, uint32_t dev, uint32_t func,
+    uint32_t reg, uint8_t data)
+{
+     _pci_conf_write(seg, bus, dev, func, reg, data, 1);
+}
+
+void pci_conf_write16(
+    uint32_t seg, uint32_t bus, uint32_t dev, uint32_t func,
+    uint32_t reg, uint16_t data)
+{
+     _pci_conf_write(seg, bus, dev, func, reg, data, 2);
+}
+
+void pci_conf_write32(
+    uint32_t seg, uint32_t bus, uint32_t dev, uint32_t func,
+    uint32_t reg, uint32_t data)
+{
+     _pci_conf_write(seg, bus, dev, func, reg, data, 4);
+}
+
+void arch_pci_ro_device(int seg, int bdf)
+{
+}
diff --git a/xen/drivers/passthrough/arm/Makefile b/xen/drivers/passthrough/arm/Makefile
index f4cd26e..1a41549 100644
--- a/xen/drivers/passthrough/arm/Makefile
+++ b/xen/drivers/passthrough/arm/Makefile
@@ -1,2 +1,3 @@
  obj-y += iommu.o
  obj-y += smmu.o
+obj-$(HAS_PCI) += pci.o
diff --git a/xen/drivers/passthrough/arm/pci.c b/xen/drivers/passthrough/arm/pci.c
new file mode 100644
index 0000000..07a5a78
--- /dev/null
+++ b/xen/drivers/passthrough/arm/pci.c
@@ -0,0 +1,88 @@
+/*
+ * PCI helper functions for arm for passthrough support.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ *
+ * Copyright (C) 2015 Cavium Networks
+ *
+ * Author: Manish Jaggi <manish.jaggi@cavium.com>
+ */
+#include <xen/pci.h>
+#include <asm/device.h>
+#include <xen/sched.h>
+
+int _dump_pci_devices(struct pci_seg *pseg, void *arg)
+{
+    struct pci_dev *pdev;
+
+    printk("==== segment %04x ====\n", pseg->nr);
+
+    list_for_each_entry ( pdev, &pseg->alldevs_list, alldevs_list )
+    {
+        printk("%04x:%02x:%02x.%u - dom %-3d - node %-3d - MSIs < ",
+               pseg->nr, pdev->bus,
+               PCI_SLOT(pdev->devfn), PCI_FUNC(pdev->devfn),
+               pdev->domain ? pdev->domain->domain_id : -1,
+               (pdev->node != NUMA_NO_NODE) ? pdev->node : -1);
+        printk(">\n");
+    }
+
+    return 0;
+}
+
+struct device* pci_to_dev(struct pci_dev *pci)
+{
+    if(!pci->arch.dev)
+    {
+        device_t *dev;
+        dev = xzalloc (struct device);
+        pci->arch.dev = dev;
+        dev->class = DEVICE_PCI;
+        dev->type = DEV_ENUMERATED;
+    }
+    return pci->arch.dev;
+}
+
+struct pci_dev* to_pci_dev(struct device *dev)
+{
+    if(dev->class == DEVICE_PCI)
+        return dev->pci_dev;
+    return NULL;
+}
+
+int dev_is_pci(struct device *dev)
+{
+    if(dev->class == DEVICE_PCI)
+        return 1;
+    return 0;
+}
+
+
+int pci_clean_dpci_irqs(struct domain *d)
+{
+    /* This is a placeholder function */
+    return 0;
+}
+
+struct pci_dev* pci_alloc_msix(struct pci_dev *pdev, struct pci_seg  *pseg,
+                               u8 bus, u8 devfn)
+{
+    /* This is a placeholder function. It is implemented only on x86 */
+    return 0;
+}
+
+void pci_cleanup_msi(struct pci_dev *pdev)
+{
+    /* This is a placeholder function. It is implemented only on x86 */
+}
diff --git a/xen/drivers/passthrough/arm/smmu.c b/xen/drivers/passthrough/arm/smmu.c
index 8a9b58b..1406261 100644
--- a/xen/drivers/passthrough/arm/smmu.c
+++ b/xen/drivers/passthrough/arm/smmu.c
@@ -183,7 +183,6 @@ static void __iomem *devm_ioremap_resource(struct device *dev,
   * Xen: PCI functions
   * TODO: It should be implemented when PCI will be supported
   */
-#define to_pci_dev(dev)	(NULL)
  static inline int pci_for_each_dma_alias(struct pci_dev *pdev,
  					 int (*fn) (struct pci_dev *pdev,
  						    u16 alias, void *data),
diff --git a/xen/drivers/passthrough/pci.c b/xen/drivers/passthrough/pci.c
index 004aba9..68c292b 100644
--- a/xen/drivers/passthrough/pci.c
+++ b/xen/drivers/passthrough/pci.c
@@ -1252,9 +1252,12 @@ static int assign_device(struct domain *d, u16 seg, u8 bus, u8 devfn)
      /* Prevent device assign if mem paging or mem sharing have been
       * enabled for this domain */
      if ( unlikely(!need_iommu(d) &&
-            (d->arch.hvm_domain.mem_sharing_enabled ||
-             d->mem_event->paging.ring_page ||
-             p2m_get_hostp2m(d)->global_logdirty)) )
+            (d->mem_event->paging.ring_page
+#ifdef CONFIG_X86
+             || d->arch.hvm_domain.mem_sharing_enabled ||
+             p2m_get_hostp2m(d)->global_logdirty
+#endif
+            )) )
          return -EXDEV;
  
      if ( !spin_trylock(&pcidevs_lock) )
diff --git a/xen/include/asm-arm/device.h b/xen/include/asm-arm/device.h
index a72f7c9..009ff0a 100644
--- a/xen/include/asm-arm/device.h
+++ b/xen/include/asm-arm/device.h
@@ -6,6 +6,17 @@
  enum device_type
  {
      DEV_DT,
+    DEV_ENUMERATED,
+};
+
+enum device_class
+{
+    DEVICE_SERIAL,
+    DEVICE_IOMMU,
+    DEVICE_GIC,
+    DEVICE_PCI,
+    /* Use for error */
+    DEVICE_UNKNOWN,
  };
  
  struct dev_archdata {
@@ -16,28 +27,30 @@ struct dev_archdata {
  struct device
  {
      enum device_type type;
+    enum device_class class;
  #ifdef HAS_DEVICE_TREE
      struct dt_device_node *of_node; /* Used by drivers imported from Linux */
  #endif
      struct dev_archdata archdata;
+#ifdef HAS_PCI
+    void *pci_dev;
+#endif
  };
  
  typedef struct device device_t;
  
  #include <xen/device_tree.h>
  
-/* TODO: Correctly implement dev_is_pci when PCI is supported on ARM */
-#define dev_is_pci(dev) ((void)(dev), 0)
  #define dev_is_dt(dev)  ((dev->type == DEV_DT)
  
-enum device_class
-{
-    DEVICE_SERIAL,
-    DEVICE_IOMMU,
-    DEVICE_GIC,
-    /* Use for error */
-    DEVICE_UNKNOWN,
-};
+struct pci_dev;
+device_t* pci_to_dev(struct pci_dev *pci);
+#ifndef HAS_PCI
+#define to_pci_dev(dev) (NULL)
+#else
+struct pci_dev* to_pci_dev(device_t *dev);
+#endif
+int dev_is_pci(device_t *dev);
  
  struct device_desc {
      /* Device name */
diff --git a/xen/include/asm-arm/domain.h b/xen/include/asm-arm/domain.h
index 9e0419e..41ae847 100644
--- a/xen/include/asm-arm/domain.h
+++ b/xen/include/asm-arm/domain.h
@@ -42,6 +42,8 @@ struct vtimer {
          uint64_t cval;
  };
  
+#define has_arch_pdevs(d)    (!list_empty(&(d)->arch.pdev_list))
+
  struct arch_domain
  {
  #ifdef CONFIG_ARM_64
@@ -56,6 +58,7 @@ struct arch_domain
      xen_pfn_t *grant_table_gpfn;
  
      struct io_handler io_handlers;
+    struct list_head pdev_list;
      /* Continuable domain_relinquish_resources(). */
      enum {
          RELMEM_not_started,
diff --git a/xen/include/asm-arm/pci.h b/xen/include/asm-arm/pci.h
index de13359..b8ec882 100644
--- a/xen/include/asm-arm/pci.h
+++ b/xen/include/asm-arm/pci.h
@@ -1,7 +1,8 @@
-#ifndef __X86_PCI_H__
-#define __X86_PCI_H__
+#ifndef __ARM_PCI_H__
+#define __ARM_PCI_H__
  
  struct arch_pci_dev {
+    void *dev;
  };
  
-#endif /* __X86_PCI_H__ */
+#endif /* __ARM_PCI_H__ */
-- 
1.7.9.5