[PATCH v8 0/4] PCI devices passthrough on Arm, part 2

[PATCH v8 0/4] PCI devices passthrough on Arm, part 2

[Oleksandr Andrushchenko]

From: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com>

Hi, all!

This is an assorted series of patches which aim is to make some further
basis for PCI passthrough on Arm support. The series continues the work
published earlier by Arm [1] and adds new helpers and clears the way for
vPCI changes which will follow.

RFC is at [2], [3]. Design presentation can be found at [4].

I have removed patch
[PATCH v6 5/7] xen/arm: do not map IRQs and memory for disabled devices
as it seems that this needs more time for decision on how to achive
that.

I have also added a new patch
[PATCH v7 4/7] xen/arm: account IO handler for emulated PCI host bridge
with a tiny latent bug fix.

This series contains all the patches which are left un-committed yet.

Thank you,
Oleksandr

[1] https://patchwork.kernel.org/project/xen-devel/list/?series=558681
[2] https://lists.xenproject.org/archives/html/xen-devel/2020-07/msg01184.html
[3] https://lists.xenproject.org/archives/html/xen-devel/2020-07/threads.html#01184
[4] https://static.sched.com/hosted_files/xen2021/e4/PCI_Device_Passthrough_On_Arm.pdf

Oleksandr Andrushchenko (4):
  xen/arm: add pci-domain for disabled devices
  xen/arm: setup MMIO range trap handlers for hardware domain
  xen/arm: account IO handler for emulated PCI host bridge
  xen/arm: do not map PCI ECAM and MMIO space to Domain-0's p2m

 xen/arch/arm/domain.c              |   2 +
 xen/arch/arm/domain_build.c        | 132 ++++++++++++++++++++---------
 xen/arch/arm/pci/ecam.c            |  14 +++
 xen/arch/arm/pci/pci-host-common.c |  77 ++++++++++++++++-
 xen/arch/arm/pci/pci-host-zynqmp.c |   1 +
 xen/arch/arm/vpci.c                |  85 ++++++++++++++++---
 xen/arch/arm/vpci.h                |   6 ++
 xen/include/asm-arm/pci.h          |  22 +++++
 xen/include/asm-arm/setup.h        |  13 +++
 9 files changed, 298 insertions(+), 54 deletions(-)

-- 
2.25.1

[PATCH v8 1/4] xen/arm: add pci-domain for disabled devices

[Oleksandr Andrushchenko]

From: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com>

If a PCI host bridge device is present in the device tree, but is
disabled, then its PCI host bridge driver was not instantiated.
This results in the failure of the pci_get_host_bridge_segment()
and the following panic during Xen start:

(XEN) Device tree generation failed (-22).
(XEN)
(XEN) ****************************************
(XEN) Panic on CPU 0:
(XEN) Could not set up DOM0 guest OS
(XEN) ****************************************

Fix this by adding "linux,pci-domain" property for all device tree nodes
which have "pci" device type, so we know which segments will be used by
the guest for which bridges.

Fixes: 4cfab4425d39 ("xen/arm: Add linux,pci-domain property for hwdom if not available.")

Signed-off-by: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com>
Reviewed-by: Rahul Singh <rahul.singh@arm.com>
Tested-by: Rahul Singh <rahul.singh@arm.com>
Acked-by: Julien Grall <jgrall@amazon.com>
---
Since v6:
- use use_dt_domains in pci_get_new_domain_nr and return -1 if set
- do not set "linux,pci-domain" if parent device is "pci"
- move the code to a new helper handle_linux_pci_domain (Julien)
New in v6
---
 xen/arch/arm/domain_build.c        | 66 +++++++++++++++++++++++-------
 xen/arch/arm/pci/pci-host-common.c |  8 +++-
 xen/include/asm-arm/pci.h          |  8 ++++
 3 files changed, 66 insertions(+), 16 deletions(-)

diff --git a/xen/arch/arm/domain_build.c b/xen/arch/arm/domain_build.c
index d02bacbcd1ed..6c5d22d9be1a 100644
--- a/xen/arch/arm/domain_build.c
+++ b/xen/arch/arm/domain_build.c
@@ -654,6 +654,55 @@ static void __init allocate_static_memory(struct domain *d,
 }
 #endif
 
+/*
+ * When PCI passthrough is available we want to keep the
+ * "linux,pci-domain" in sync for every host bridge.
+ *
+ * Xen may not have a driver for all the host bridges. So we have
+ * to write an heuristic to detect whether a device node describes
+ * a host bridge.
+ *
+ * The current heuristic assumes that a device is a host bridge
+ * if the type is "pci" and then parent type is not "pci".
+ */
+static int handle_linux_pci_domain(struct kernel_info *kinfo,
+                                   const struct dt_device_node *node)
+{
+    uint16_t segment;
+    int res;
+
+    if ( !is_pci_passthrough_enabled() )
+        return 0;
+
+    if ( !dt_device_type_is_equal(node, "pci") )
+        return 0;
+
+    if ( node->parent && dt_device_type_is_equal(node->parent, "pci") )
+        return 0;
+
+    if ( dt_find_property(node, "linux,pci-domain", NULL) )
+        return 0;
+
+    /* Allocate and create the linux,pci-domain */
+    res = pci_get_host_bridge_segment(node, &segment);
+    if ( res < 0 )
+    {
+        res = pci_get_new_domain_nr();
+        if ( res < 0 )
+        {
+            printk(XENLOG_DEBUG "Can't assign PCI segment to %s\n",
+                   node->full_name);
+            return -FDT_ERR_NOTFOUND;
+        }
+
+        segment = res;
+        printk(XENLOG_DEBUG "Assigned segment %d to %s\n",
+               segment, node->full_name);
+    }
+
+    return fdt_property_cell(kinfo->fdt, "linux,pci-domain", segment);
+}
+
 static int __init write_properties(struct domain *d, struct kernel_info *kinfo,
                                    const struct dt_device_node *node)
 {
@@ -755,21 +804,10 @@ static int __init write_properties(struct domain *d, struct kernel_info *kinfo,
             return res;
     }
 
-    if ( is_pci_passthrough_enabled() && dt_device_type_is_equal(node, "pci") )
-    {
-        if ( !dt_find_property(node, "linux,pci-domain", NULL) )
-        {
-            uint16_t segment;
-
-            res = pci_get_host_bridge_segment(node, &segment);
-            if ( res < 0 )
-                return res;
+    res = handle_linux_pci_domain(kinfo, node);
 
-            res = fdt_property_cell(kinfo->fdt, "linux,pci-domain", segment);
-            if ( res )
-                return res;
-        }
-    }
+    if ( res )
+        return res;
 
     /*
      * Override the property "status" to disable the device when it's
diff --git a/xen/arch/arm/pci/pci-host-common.c b/xen/arch/arm/pci/pci-host-common.c
index ae79a0c19b93..40e779b5d803 100644
--- a/xen/arch/arm/pci/pci-host-common.c
+++ b/xen/arch/arm/pci/pci-host-common.c
@@ -30,6 +30,8 @@ static LIST_HEAD(pci_host_bridges);
 
 static atomic_t domain_nr = ATOMIC_INIT(-1);
 
+static int use_dt_domains = -1;
+
 static inline void __iomem *pci_remap_cfgspace(paddr_t start, size_t len)
 {
     return ioremap_nocache(start, len);
@@ -137,14 +139,16 @@ void pci_add_host_bridge(struct pci_host_bridge *bridge)
     list_add_tail(&bridge->node, &pci_host_bridges);
 }
 
-static int pci_get_new_domain_nr(void)
+int pci_get_new_domain_nr(void)
 {
+    if ( use_dt_domains )
+        return -1;
+
     return atomic_inc_return(&domain_nr);
 }
 
 static int pci_bus_find_domain_nr(struct dt_device_node *dev)
 {
-    static int use_dt_domains = -1;
     int domain;
 
     domain = dt_get_pci_domain_nr(dev);
diff --git a/xen/include/asm-arm/pci.h b/xen/include/asm-arm/pci.h
index 9736d6816da3..c313423cdcb2 100644
--- a/xen/include/asm-arm/pci.h
+++ b/xen/include/asm-arm/pci.h
@@ -109,6 +109,8 @@ static always_inline bool is_pci_passthrough_enabled(void)
 
 void arch_pci_init_pdev(struct pci_dev *pdev);
 
+int pci_get_new_domain_nr(void);
+
 #else   /*!CONFIG_HAS_PCI*/
 
 struct arch_pci_dev { };
@@ -129,5 +131,11 @@ static inline int pci_get_host_bridge_segment(const struct dt_device_node *node,
     return -EINVAL;
 }
 
+static inline int pci_get_new_domain_nr(void)
+{
+    ASSERT_UNREACHABLE();
+    return -1;
+}
+
 #endif  /*!CONFIG_HAS_PCI*/
 #endif /* __ARM_PCI_H__ */
-- 
2.25.1

[PATCH v8 2/4] xen/arm: setup MMIO range trap handlers for hardware domain

[Oleksandr Andrushchenko]

From: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com>

In order for vPCI to work it needs to maintain guest and hardware
domain's views of the configuration space. For example, BARs and
COMMAND registers require emulation for guests and the guest view
of the registers needs to be in sync with the real contents of the
relevant registers. For that ECAM address space needs to also be
trapped for the hardware domain, so we need to implement PCI host
bridge specific callbacks to properly setup MMIO handlers for those
ranges depending on particular host bridge implementation.

Signed-off-by: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com>
---
Since v7:
- move local variable inside the loop in pci_host_iterate_bridges_and_count
  and s/err/ret
- fixed incorrect s/if ( err )/if ( err < 0 )
- moved the guest part in an else in domain_vpci_init
- s/count/ret in domain_vpci_init as it better reflects the use of the
  value
Since v6:
- eliminate pci_host_get_num_bridges and make pci_host_iterate_bridges
  return the count
- extend comment in domain_vpci_init
- remove not yet relevant code for num MMIOs and virtual bus topology
- add extra check for has_vpci in domain_vpci_get_num_mmio_handlers
- remove code that fixes num MMIOs for guest domain as it doesn't belong
  to this patch
Since v5:
- add vpci_sbdf_from_gpa helper for gpa to SBDF translation
- take bridge's bus start into account while calculating SBDF
Since v4:
- unsigned int for functions working with count
- gate number of MMIO handlers needed for CONFIG_HAS_PCI_MSI
  and fix their number, e.g. single handler for PBA and
  MSI-X tables (Roger)
- re-work code for assigning MMIO handlers to be simpler
  and account on the fact that there could multiple host bridges
  exist for the hwdom
Since v3:
- fixed comment formatting
Since v2:
- removed unneeded assignment (count = 0)
- removed unneeded header inclusion
- update commit message
Since v1:
 - Dynamically calculate the number of MMIO handlers required for vPCI
   and update the total number accordingly
 - s/clb/cb
 - Do not introduce a new callback for MMIO handler setup
---
 xen/arch/arm/domain.c              |  2 +
 xen/arch/arm/pci/pci-host-common.c | 19 +++++++
 xen/arch/arm/vpci.c                | 81 ++++++++++++++++++++++++++----
 xen/arch/arm/vpci.h                |  6 +++
 xen/include/asm-arm/pci.h          |  4 ++
 5 files changed, 102 insertions(+), 10 deletions(-)

diff --git a/xen/arch/arm/domain.c b/xen/arch/arm/domain.c
index 96e1b235501d..92a6c509e5c5 100644
--- a/xen/arch/arm/domain.c
+++ b/xen/arch/arm/domain.c
@@ -739,6 +739,8 @@ int arch_domain_create(struct domain *d,
     if ( (rc = domain_vgic_register(d, &count)) != 0 )
         goto fail;
 
+    count += domain_vpci_get_num_mmio_handlers(d);
+
     if ( (rc = domain_io_init(d, count + MAX_IO_HANDLER)) != 0 )
         goto fail;
 
diff --git a/xen/arch/arm/pci/pci-host-common.c b/xen/arch/arm/pci/pci-host-common.c
index 40e779b5d803..84aab371cd9a 100644
--- a/xen/arch/arm/pci/pci-host-common.c
+++ b/xen/arch/arm/pci/pci-host-common.c
@@ -294,6 +294,25 @@ int pci_get_host_bridge_segment(const struct dt_device_node *node,
     return -EINVAL;
 }
 
+int pci_host_iterate_bridges_and_count(struct domain *d,
+                                       int (*cb)(struct domain *d,
+                                                 struct pci_host_bridge *bridge))
+{
+    struct pci_host_bridge *bridge;
+    int count = 0;
+
+    list_for_each_entry( bridge, &pci_host_bridges, node )
+    {
+        int ret;
+
+        ret = cb(d, bridge);
+        if ( ret < 0 )
+            return ret;
+        count += ret;
+    }
+    return count;
+}
+
 /*
  * Local variables:
  * mode: C
diff --git a/xen/arch/arm/vpci.c b/xen/arch/arm/vpci.c
index 23f45386f4b3..1564448c6c8d 100644
--- a/xen/arch/arm/vpci.c
+++ b/xen/arch/arm/vpci.c
@@ -16,16 +16,31 @@
 
 #include <asm/mmio.h>
 
+static pci_sbdf_t vpci_sbdf_from_gpa(const struct pci_host_bridge *bridge,
+                                     paddr_t gpa)
+{
+    pci_sbdf_t sbdf;
+
+    if ( bridge )
+    {
+        sbdf.sbdf = VPCI_ECAM_BDF(gpa - bridge->cfg->phys_addr);
+        sbdf.seg = bridge->segment;
+        sbdf.bus += bridge->cfg->busn_start;
+    }
+    else
+        sbdf.sbdf = VPCI_ECAM_BDF(gpa - GUEST_VPCI_ECAM_BASE);
+
+    return sbdf;
+}
+
 static int vpci_mmio_read(struct vcpu *v, mmio_info_t *info,
                           register_t *r, void *p)
 {
-    pci_sbdf_t sbdf;
+    struct pci_host_bridge *bridge = p;
+    pci_sbdf_t sbdf = vpci_sbdf_from_gpa(bridge, info->gpa);
     /* data is needed to prevent a pointer cast on 32bit */
     unsigned long data;
 
-    /* We ignore segment part and always handle segment 0 */
-    sbdf.sbdf = VPCI_ECAM_BDF(info->gpa - GUEST_VPCI_ECAM_BASE);
-
     if ( vpci_ecam_read(sbdf, ECAM_REG_OFFSET(info->gpa),
                         1U << info->dabt.size, &data) )
     {
@@ -41,10 +56,8 @@ static int vpci_mmio_read(struct vcpu *v, mmio_info_t *info,
 static int vpci_mmio_write(struct vcpu *v, mmio_info_t *info,
                            register_t r, void *p)
 {
-    pci_sbdf_t sbdf;
-
-    /* We ignore segment part and always handle segment 0 */
-    sbdf.sbdf = VPCI_ECAM_BDF(info->gpa - GUEST_VPCI_ECAM_BASE);
+    struct pci_host_bridge *bridge = p;
+    pci_sbdf_t sbdf = vpci_sbdf_from_gpa(bridge, info->gpa);
 
     return vpci_ecam_write(sbdf, ECAM_REG_OFFSET(info->gpa),
                            1U << info->dabt.size, r);
@@ -55,13 +68,61 @@ static const struct mmio_handler_ops vpci_mmio_handler = {
     .write = vpci_mmio_write,
 };
 
+static int vpci_setup_mmio_handler_cb(struct domain *d,
+                                      struct pci_host_bridge *bridge)
+{
+    struct pci_config_window *cfg = bridge->cfg;
+
+    register_mmio_handler(d, &vpci_mmio_handler,
+                          cfg->phys_addr, cfg->size, bridge);
+
+    /* We have registered a single MMIO handler. */
+    return 1;
+}
+
 int domain_vpci_init(struct domain *d)
 {
     if ( !has_vpci(d) )
         return 0;
 
-    register_mmio_handler(d, &vpci_mmio_handler,
-                          GUEST_VPCI_ECAM_BASE, GUEST_VPCI_ECAM_SIZE, NULL);
+    /*
+     * The hardware domain gets as many MMIOs as required by the
+     * physical host bridge.
+     * Guests get the virtual platform layout: one virtual host bridge for now.
+     */
+    if ( is_hardware_domain(d) )
+    {
+        int ret;
+
+        ret = pci_host_iterate_bridges_and_count(d, vpci_setup_mmio_handler_cb);
+        if ( ret < 0 )
+            return ret;
+    }
+    else
+        register_mmio_handler(d, &vpci_mmio_handler,
+                              GUEST_VPCI_ECAM_BASE, GUEST_VPCI_ECAM_SIZE, NULL);
+
+    return 0;
+}
+
+static int vpci_get_num_handlers_cb(struct domain *d,
+                                    struct pci_host_bridge *bridge)
+{
+    /* Each bridge has a single MMIO handler for the configuration space. */
+    return 1;
+}
+
+unsigned int domain_vpci_get_num_mmio_handlers(struct domain *d)
+{
+    if ( !has_vpci(d) )
+        return 0;
+
+    if ( is_hardware_domain(d) )
+    {
+        int ret = pci_host_iterate_bridges_and_count(d, vpci_get_num_handlers_cb);
+
+        return ret < 0 ? 0 : ret;
+    }
 
     return 0;
 }
diff --git a/xen/arch/arm/vpci.h b/xen/arch/arm/vpci.h
index d8a7b0e3e802..3c713f3fcdb5 100644
--- a/xen/arch/arm/vpci.h
+++ b/xen/arch/arm/vpci.h
@@ -17,11 +17,17 @@
 
 #ifdef CONFIG_HAS_VPCI
 int domain_vpci_init(struct domain *d);
+unsigned int domain_vpci_get_num_mmio_handlers(struct domain *d);
 #else
 static inline int domain_vpci_init(struct domain *d)
 {
     return 0;
 }
+
+static inline unsigned int domain_vpci_get_num_mmio_handlers(struct domain *d)
+{
+    return 0;
+}
 #endif
 
 #endif /* __ARCH_ARM_VPCI_H__ */
diff --git a/xen/include/asm-arm/pci.h b/xen/include/asm-arm/pci.h
index c313423cdcb2..94f003a07ca2 100644
--- a/xen/include/asm-arm/pci.h
+++ b/xen/include/asm-arm/pci.h
@@ -111,6 +111,10 @@ void arch_pci_init_pdev(struct pci_dev *pdev);
 
 int pci_get_new_domain_nr(void);
 
+int pci_host_iterate_bridges_and_count(struct domain *d,
+                                       int (*cb)(struct domain *d,
+                                                 struct pci_host_bridge *bridge));
+
 #else   /*!CONFIG_HAS_PCI*/
 
 struct arch_pci_dev { };
-- 
2.25.1

[PATCH v8 3/4] xen/arm: account IO handler for emulated PCI host bridge

[Oleksandr Andrushchenko]

From: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com>

At the moment, we always allocate an extra 16 slots for IO handlers
(see MAX_IO_HANDLER). So while adding an IO trap handler for the emulated
PCI host bridge we are not breaking anything, but we have a latent bug
as the maximum number of IOs may be exceeded.
Fix this by explicitly telling that we have an additional IO handler, so it is
accounted.

Fixes: d59168dc05a5 ("xen/arm: Enable the existing x86 virtual PCI support for ARM")

Signed-off-by: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com>
Acked-by: Julien Grall <jgrall@amazon.com>
---
Since v7:
- updated comment
New in v7
---
 xen/arch/arm/vpci.c | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/xen/arch/arm/vpci.c b/xen/arch/arm/vpci.c
index 1564448c6c8d..84aaaaebd69d 100644
--- a/xen/arch/arm/vpci.c
+++ b/xen/arch/arm/vpci.c
@@ -124,7 +124,11 @@ unsigned int domain_vpci_get_num_mmio_handlers(struct domain *d)
         return ret < 0 ? 0 : ret;
     }
 
-    return 0;
+    /*
+     * For guests each host bridge requires one region to cover the
+     * configuration space. At the moment, we only expose a single host bridge.
+     */
+    return 1;
 }
 
 /*
-- 
2.25.1

[PATCH v8 4/4] xen/arm: do not map PCI ECAM and MMIO space to Domain-0's p2m

[Oleksandr Andrushchenko]

From: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com>

PCI host bridges are special devices in terms of implementing PCI
passthrough. According to [1] the current implementation depends on
Domain-0 to perform the initialization of the relevant PCI host
bridge hardware and perform PCI device enumeration. In order to
achieve that one of the required changes is to not map all the memory
ranges in map_range_to_domain as we traverse the device tree on startup
and perform some additional checks if the range needs to be mapped to
Domain-0.

The generic PCI host controller device tree binding says [2]:
- ranges: As described in IEEE Std 1275-1994, but must provide
          at least a definition of non-prefetchable memory. One
          or both of prefetchable Memory and IO Space may also
          be provided.

- reg   : The Configuration Space base address and size, as accessed
          from the parent bus.  The base address corresponds to
          the first bus in the "bus-range" property.  If no
          "bus-range" is specified, this will be bus 0 (the default).

From the above none of the memory ranges from the "ranges" property
needs to be mapped to Domain-0 at startup as MMIO mapping is going to
be handled dynamically by vPCI as we assign PCI devices, e.g. each
device assigned to Domain-0/guest will have its MMIOs mapped/unmapped
as needed by Xen.

The "reg" property covers not only ECAM space, but may also have other
then the configuration memory ranges described, for example [3]:
- reg: Should contain rc_dbi, config registers location and length.
- reg-names: Must include the following entries:
   "rc_dbi": controller configuration registers;
   "config": PCIe configuration space registers.

This patch makes it possible to not map all the ranges from the
"ranges" property and also ECAM from the "reg". All the rest from the
"reg" property still needs to be mapped to Domain-0, so the PCI
host bridge remains functional in Domain-0. This is done by first
skipping the mappings while traversing the device tree as it is done for
usual devices and then by calling a dedicated pci_host_bridge_mappings
function which only maps MMIOs required by the host bridges leaving the
regions, needed for vPCI traps, unmapped.

[1] https://lists.xenproject.org/archives/html/xen-devel/2020-07/msg00777.html
[2] https://www.kernel.org/doc/Documentation/devicetree/bindings/pci/host-generic-pci.txt
[3] https://www.kernel.org/doc/Documentation/devicetree/bindings/pci/hisilicon-pcie.txt

Signed-off-by: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com>
Reviewed-by: Julien Grall <jgrall@amazon.com>
---
Since v7:
- updates in comments and commit message
Since v5:
- remove some need_mapping local variables
- use own_device in handle_device
- add __init for pci_ecam_need_p2m_hwdom_mapping
- make pci_host_bridge_mappings use p2m_mmio_direct_dev directly
Since v4:
- update skip_mapping comment
- add comment why we need to map interrupts to Dom0
Since v3:
 - pass struct map_range_data to map_dt_irq_to_domain
 - remove redundant check from map_range_to_domain
 - fix handle_device's .skip_mapping
Since v2:
 - removed check in map_range_to_domain for PCI_DEV
   and moved it to handle_device, so the code is
   simpler
 - s/map_pci_bridge/skip_mapping
 - extended comment in pci_host_bridge_mappings
 - minor code restructure in construct_dom0
 - s/.need_p2m_mapping/.need_p2m_hwdom_mapping and related
   callbacks
 - unsigned int i; in pci_host_bridge_mappings
Since v1:
 - Added better description of why and what needs to be mapped into
   Domain-0's p2m and what doesn't
 - Do not do any mappings for PCI devices while traversing the DT
 - Walk all the bridges and make required mappings in one go
---
 xen/arch/arm/domain_build.c        | 66 +++++++++++++++++-------------
 xen/arch/arm/pci/ecam.c            | 14 +++++++
 xen/arch/arm/pci/pci-host-common.c | 50 ++++++++++++++++++++++
 xen/arch/arm/pci/pci-host-zynqmp.c |  1 +
 xen/include/asm-arm/pci.h          | 10 +++++
 xen/include/asm-arm/setup.h        | 13 ++++++
 6 files changed, 126 insertions(+), 28 deletions(-)

diff --git a/xen/arch/arm/domain_build.c b/xen/arch/arm/domain_build.c
index 6c5d22d9be1a..6931c022a2e8 100644
--- a/xen/arch/arm/domain_build.c
+++ b/xen/arch/arm/domain_build.c
@@ -51,12 +51,6 @@ static int __init parse_dom0_mem(const char *s)
 }
 custom_param("dom0_mem", parse_dom0_mem);
 
-struct map_range_data
-{
-    struct domain *d;
-    p2m_type_t p2mt;
-};
-
 /* Override macros from asm/page.h to make them work with mfn_t */
 #undef virt_to_mfn
 #define virt_to_mfn(va) _mfn(__virt_to_mfn(va))
@@ -1720,10 +1714,10 @@ static int __init map_dt_irq_to_domain(const struct dt_device_node *dev,
                                        const struct dt_irq *dt_irq,
                                        void *data)
 {
-    struct domain *d = data;
+    struct map_range_data *mr_data = data;
+    struct domain *d = mr_data->d;
     unsigned int irq = dt_irq->irq;
     int res;
-    bool need_mapping = !dt_device_for_passthrough(dev);
 
     if ( irq < NR_LOCAL_IRQS )
     {
@@ -1742,18 +1736,16 @@ static int __init map_dt_irq_to_domain(const struct dt_device_node *dev,
         return res;
     }
 
-    res = map_irq_to_domain(d, irq, need_mapping, dt_node_name(dev));
+    res = map_irq_to_domain(d, irq, !mr_data->skip_mapping, dt_node_name(dev));
 
     return 0;
 }
 
-static int __init map_range_to_domain(const struct dt_device_node *dev,
-                                      u64 addr, u64 len,
-                                      void *data)
+int __init map_range_to_domain(const struct dt_device_node *dev,
+                               u64 addr, u64 len, void *data)
 {
     struct map_range_data *mr_data = data;
     struct domain *d = mr_data->d;
-    bool need_mapping = !dt_device_for_passthrough(dev);
     int res;
 
     /*
@@ -1776,7 +1768,7 @@ static int __init map_range_to_domain(const struct dt_device_node *dev,
         }
     }
 
-    if ( need_mapping )
+    if ( !mr_data->skip_mapping )
     {
         res = map_regions_p2mt(d,
                                gaddr_to_gfn(addr),
@@ -1805,23 +1797,21 @@ static int __init map_range_to_domain(const struct dt_device_node *dev,
  * then we may need to perform additional mappings in order to make
  * the child resources available to domain 0.
  */
-static int __init map_device_children(struct domain *d,
-                                      const struct dt_device_node *dev,
-                                      p2m_type_t p2mt)
+static int __init map_device_children(const struct dt_device_node *dev,
+                                      struct map_range_data *mr_data)
 {
-    struct map_range_data mr_data = { .d = d, .p2mt = p2mt };
-    int ret;
-
     if ( dt_device_type_is_equal(dev, "pci") )
     {
+        int ret;
+
         dt_dprintk("Mapping children of %s to guest\n",
                    dt_node_full_name(dev));
 
-        ret = dt_for_each_irq_map(dev, &map_dt_irq_to_domain, d);
+        ret = dt_for_each_irq_map(dev, &map_dt_irq_to_domain, mr_data);
         if ( ret < 0 )
             return ret;
 
-        ret = dt_for_each_range(dev, &map_range_to_domain, &mr_data);
+        ret = dt_for_each_range(dev, &map_range_to_domain, mr_data);
         if ( ret < 0 )
             return ret;
     }
@@ -1901,14 +1891,28 @@ static int __init handle_device(struct domain *d, struct dt_device_node *dev,
     unsigned int i;
     int res;
     u64 addr, size;
-    bool need_mapping = !dt_device_for_passthrough(dev);
+    bool own_device = !dt_device_for_passthrough(dev);
+    /*
+     * We want to avoid mapping the MMIO in dom0 for the following cases:
+     *   - The device is owned by dom0 (i.e. it has been flagged for
+     *     passthrough).
+     *   - PCI host bridges with driver in Xen. They will later be mapped by
+     *     pci_host_bridge_mappings().
+     */
+    struct map_range_data mr_data = {
+        .d = d,
+        .p2mt = p2mt,
+        .skip_mapping = !own_device ||
+                        (is_pci_passthrough_enabled() &&
+                        (device_get_class(dev) == DEVICE_PCI_HOSTBRIDGE))
+    };
 
     naddr = dt_number_of_address(dev);
 
     dt_dprintk("%s passthrough = %d naddr = %u\n",
-               dt_node_full_name(dev), need_mapping, naddr);
+               dt_node_full_name(dev), own_device, naddr);
 
-    if ( need_mapping )
+    if ( own_device )
     {
         dt_dprintk("Check if %s is behind the IOMMU and add it\n",
                    dt_node_full_name(dev));
@@ -1934,14 +1938,13 @@ static int __init handle_device(struct domain *d, struct dt_device_node *dev,
         }
     }
 
-    res = handle_device_interrupts(d, dev, need_mapping);
+    res = handle_device_interrupts(d, dev, own_device);
     if ( res < 0 )
         return res;
 
     /* Give permission and map MMIOs */
     for ( i = 0; i < naddr; i++ )
     {
-        struct map_range_data mr_data = { .d = d, .p2mt = p2mt };
         res = dt_device_get_address(dev, i, &addr, &size);
         if ( res )
         {
@@ -1955,7 +1958,7 @@ static int __init handle_device(struct domain *d, struct dt_device_node *dev,
             return res;
     }
 
-    res = map_device_children(d, dev, p2mt);
+    res = map_device_children(dev, &mr_data);
     if ( res )
         return res;
 
@@ -3114,7 +3117,14 @@ static int __init construct_dom0(struct domain *d)
         return rc;
 
     if ( acpi_disabled )
+    {
         rc = prepare_dtb_hwdom(d, &kinfo);
+        if ( rc < 0 )
+            return rc;
+#ifdef CONFIG_HAS_PCI
+        rc = pci_host_bridge_mappings(d);
+#endif
+    }
     else
         rc = prepare_acpi(d, &kinfo);
 
diff --git a/xen/arch/arm/pci/ecam.c b/xen/arch/arm/pci/ecam.c
index 2855dea213f4..6aeea12a68bf 100644
--- a/xen/arch/arm/pci/ecam.c
+++ b/xen/arch/arm/pci/ecam.c
@@ -40,6 +40,19 @@ void __iomem *pci_ecam_map_bus(struct pci_host_bridge *bridge,
     return base + (PCI_DEVFN2(sbdf.bdf) << devfn_shift) + where;
 }
 
+bool __init pci_ecam_need_p2m_hwdom_mapping(struct domain *d,
+                                            struct pci_host_bridge *bridge,
+                                            uint64_t addr)
+{
+    struct pci_config_window *cfg = bridge->cfg;
+
+    /*
+     * We do not want ECAM address space to be mapped in Domain-0's p2m,
+     * so we can trap access to it.
+     */
+    return cfg->phys_addr != addr;
+}
+
 /* ECAM ops */
 const struct pci_ecam_ops pci_generic_ecam_ops = {
     .bus_shift  = 20,
@@ -47,6 +60,7 @@ const struct pci_ecam_ops pci_generic_ecam_ops = {
         .map_bus                = pci_ecam_map_bus,
         .read                   = pci_generic_config_read,
         .write                  = pci_generic_config_write,
+        .need_p2m_hwdom_mapping = pci_ecam_need_p2m_hwdom_mapping,
     }
 };
 
diff --git a/xen/arch/arm/pci/pci-host-common.c b/xen/arch/arm/pci/pci-host-common.c
index 84aab371cd9a..fd8c0f837a6a 100644
--- a/xen/arch/arm/pci/pci-host-common.c
+++ b/xen/arch/arm/pci/pci-host-common.c
@@ -22,6 +22,8 @@
 #include <xen/sched.h>
 #include <xen/vmap.h>
 
+#include <asm/setup.h>
+
 /*
  * List for all the pci host bridges.
  */
@@ -313,6 +315,54 @@ int pci_host_iterate_bridges_and_count(struct domain *d,
     return count;
 }
 
+/*
+ * For each PCI host bridge we need to only map those ranges
+ * which are used by Domain-0 to properly initialize the bridge,
+ * e.g. we do not want to map ECAM configuration space which lives in
+ * "reg" device tree property, but we want to map other regions of
+ * the host bridge. The PCI aperture defined by the "ranges" device
+ * tree property should also be skipped.
+ */
+int __init pci_host_bridge_mappings(struct domain *d)
+{
+    struct pci_host_bridge *bridge;
+    struct map_range_data mr_data = {
+        .d = d,
+        .p2mt = p2m_mmio_direct_dev,
+        .skip_mapping = false
+    };
+
+    list_for_each_entry( bridge, &pci_host_bridges, node )
+    {
+        const struct dt_device_node *dev = bridge->dt_node;
+        unsigned int i;
+
+        for ( i = 0; i < dt_number_of_address(dev); i++ )
+        {
+            uint64_t addr, size;
+            int err;
+
+            err = dt_device_get_address(dev, i, &addr, &size);
+            if ( err )
+            {
+                printk(XENLOG_ERR
+                       "Unable to retrieve address range index=%u for %s\n",
+                       i, dt_node_full_name(dev));
+                return err;
+            }
+
+            if ( bridge->ops->need_p2m_hwdom_mapping(d, bridge, addr) )
+            {
+                err = map_range_to_domain(dev, addr, size, &mr_data);
+                if ( err )
+                    return err;
+            }
+        }
+    }
+
+    return 0;
+}
+
 /*
  * Local variables:
  * mode: C
diff --git a/xen/arch/arm/pci/pci-host-zynqmp.c b/xen/arch/arm/pci/pci-host-zynqmp.c
index 516982bca833..101edb8593c1 100644
--- a/xen/arch/arm/pci/pci-host-zynqmp.c
+++ b/xen/arch/arm/pci/pci-host-zynqmp.c
@@ -34,6 +34,7 @@ const struct pci_ecam_ops nwl_pcie_ops = {
         .map_bus                = pci_ecam_map_bus,
         .read                   = pci_generic_config_read,
         .write                  = pci_generic_config_write,
+        .need_p2m_hwdom_mapping = pci_ecam_need_p2m_hwdom_mapping,
     }
 };
 
diff --git a/xen/include/asm-arm/pci.h b/xen/include/asm-arm/pci.h
index 94f003a07ca2..7c7449d64fca 100644
--- a/xen/include/asm-arm/pci.h
+++ b/xen/include/asm-arm/pci.h
@@ -17,6 +17,8 @@
 
 #ifdef CONFIG_HAS_PCI
 
+#include <asm/p2m.h>
+
 #define pci_to_dev(pcidev) (&(pcidev)->arch.dev)
 
 extern bool pci_passthrough_enabled;
@@ -73,6 +75,9 @@ struct pci_ops {
                 uint32_t reg, uint32_t len, uint32_t *value);
     int (*write)(struct pci_host_bridge *bridge, pci_sbdf_t sbdf,
                  uint32_t reg, uint32_t len, uint32_t value);
+    bool (*need_p2m_hwdom_mapping)(struct domain *d,
+                                   struct pci_host_bridge *bridge,
+                                   uint64_t addr);
 };
 
 /*
@@ -97,6 +102,9 @@ int pci_generic_config_write(struct pci_host_bridge *bridge, pci_sbdf_t sbdf,
                              uint32_t reg, uint32_t len, uint32_t value);
 void __iomem *pci_ecam_map_bus(struct pci_host_bridge *bridge,
                                pci_sbdf_t sbdf, uint32_t where);
+bool pci_ecam_need_p2m_hwdom_mapping(struct domain *d,
+                                     struct pci_host_bridge *bridge,
+                                     uint64_t addr);
 struct pci_host_bridge *pci_find_host_bridge(uint16_t segment, uint8_t bus);
 struct dt_device_node *pci_find_host_bridge_node(struct device *dev);
 int pci_get_host_bridge_segment(const struct dt_device_node *node,
@@ -115,6 +123,8 @@ int pci_host_iterate_bridges_and_count(struct domain *d,
                                        int (*cb)(struct domain *d,
                                                  struct pci_host_bridge *bridge));
 
+int pci_host_bridge_mappings(struct domain *d);
+
 #else   /*!CONFIG_HAS_PCI*/
 
 struct arch_pci_dev { };
diff --git a/xen/include/asm-arm/setup.h b/xen/include/asm-arm/setup.h
index 95da0b7ab9cd..88d9673db817 100644
--- a/xen/include/asm-arm/setup.h
+++ b/xen/include/asm-arm/setup.h
@@ -2,6 +2,8 @@
 #define __ARM_SETUP_H_
 
 #include <public/version.h>
+#include <asm/p2m.h>
+#include <xen/device_tree.h>
 
 #define MIN_FDT_ALIGN 8
 #define MAX_FDT_SIZE SZ_2M
@@ -77,6 +79,14 @@ struct bootinfo {
 #endif
 };
 
+struct map_range_data
+{
+    struct domain *d;
+    p2m_type_t p2mt;
+    /* Set if mapping of the memory ranges must be skipped. */
+    bool skip_mapping;
+};
+
 extern struct bootinfo bootinfo;
 
 extern domid_t max_init_domid;
@@ -124,6 +134,9 @@ void device_tree_get_reg(const __be32 **cell, u32 address_cells,
 u32 device_tree_get_u32(const void *fdt, int node,
                         const char *prop_name, u32 dflt);
 
+int map_range_to_domain(const struct dt_device_node *dev,
+                        u64 addr, u64 len, void *data);
+
 #endif
 /*
  * Local variables:
-- 
2.25.1

Re: [PATCH v8 2/4] xen/arm: setup MMIO range trap handlers for hardware domain

[Rahul Singh]

Hi Oleksandr,

> On 9 Dec 2021, at 7:29 am, Oleksandr Andrushchenko <andr2000@gmail.com> wrote:
> 
> From: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com>
> 
> In order for vPCI to work it needs to maintain guest and hardware
> domain's views of the configuration space. For example, BARs and
> COMMAND registers require emulation for guests and the guest view
> of the registers needs to be in sync with the real contents of the
> relevant registers. For that ECAM address space needs to also be
> trapped for the hardware domain, so we need to implement PCI host
> bridge specific callbacks to properly setup MMIO handlers for those
> ranges depending on particular host bridge implementation.
> 
> Signed-off-by: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com>

Reviewed-by: Rahul Singh <rahul.singh@arm.com>
Tested-by: Rahul Singh <rahul.singh@arm.com>

Regards,
Rahul

Re: [PATCH v8 3/4] xen/arm: account IO handler for emulated PCI host bridge

[Rahul Singh]

Hi Oleksandr,

> On 9 Dec 2021, at 7:29 am, Oleksandr Andrushchenko <andr2000@gmail.com> wrote:
> 
> From: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com>
> 
> At the moment, we always allocate an extra 16 slots for IO handlers
> (see MAX_IO_HANDLER). So while adding an IO trap handler for the emulated
> PCI host bridge we are not breaking anything, but we have a latent bug
> as the maximum number of IOs may be exceeded.
> Fix this by explicitly telling that we have an additional IO handler, so it is
> accounted.
> 
> Fixes: d59168dc05a5 ("xen/arm: Enable the existing x86 virtual PCI support for ARM")
> 
> Signed-off-by: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com>
> Acked-by: Julien Grall <jgrall@amazon.com>

Reviewed-by: Rahul Singh <rahul.singh@arm.com>
Tested-by: Rahul Singh <rahul.singh@arm.com>

Regards,
Rahul

Re: [PATCH v8 4/4] xen/arm: do not map PCI ECAM and MMIO space to Domain-0's p2m

[Rahul Singh]

Hi Oleksandr,

> On 9 Dec 2021, at 7:29 am, Oleksandr Andrushchenko <andr2000@gmail.com> wrote:
> 
> From: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com>
> 
> PCI host bridges are special devices in terms of implementing PCI
> passthrough. According to [1] the current implementation depends on
> Domain-0 to perform the initialization of the relevant PCI host
> bridge hardware and perform PCI device enumeration. In order to
> achieve that one of the required changes is to not map all the memory
> ranges in map_range_to_domain as we traverse the device tree on startup
> and perform some additional checks if the range needs to be mapped to
> Domain-0.
> 
> The generic PCI host controller device tree binding says [2]:
> - ranges: As described in IEEE Std 1275-1994, but must provide
>          at least a definition of non-prefetchable memory. One
>          or both of prefetchable Memory and IO Space may also
>          be provided.
> 
> - reg   : The Configuration Space base address and size, as accessed
>          from the parent bus.  The base address corresponds to
>          the first bus in the "bus-range" property.  If no
>          "bus-range" is specified, this will be bus 0 (the default).
> 
> From the above none of the memory ranges from the "ranges" property
> needs to be mapped to Domain-0 at startup as MMIO mapping is going to
> be handled dynamically by vPCI as we assign PCI devices, e.g. each
> device assigned to Domain-0/guest will have its MMIOs mapped/unmapped
> as needed by Xen.
> 
> The "reg" property covers not only ECAM space, but may also have other
> then the configuration memory ranges described, for example [3]:
> - reg: Should contain rc_dbi, config registers location and length.
> - reg-names: Must include the following entries:
>   "rc_dbi": controller configuration registers;
>   "config": PCIe configuration space registers.
> 
> This patch makes it possible to not map all the ranges from the
> "ranges" property and also ECAM from the "reg". All the rest from the
> "reg" property still needs to be mapped to Domain-0, so the PCI
> host bridge remains functional in Domain-0. This is done by first
> skipping the mappings while traversing the device tree as it is done for
> usual devices and then by calling a dedicated pci_host_bridge_mappings
> function which only maps MMIOs required by the host bridges leaving the
> regions, needed for vPCI traps, unmapped.
> 
> [1] https://lists.xenproject.org/archives/html/xen-devel/2020-07/msg00777.html
> [2] https://www.kernel.org/doc/Documentation/devicetree/bindings/pci/host-generic-pci.txt
> [3] https://www.kernel.org/doc/Documentation/devicetree/bindings/pci/hisilicon-pcie.txt
> 
> Signed-off-by: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com>
> Reviewed-by: Julien Grall <jgrall@amazon.com>

Reviewed-by: Rahul Singh <rahul.singh@arm.com>
Tested-by: Rahul Singh <rahul.singh@arm.com>

Regards,
Rahul
 

Re: [PATCH v8 2/4] xen/arm: setup MMIO range trap handlers for hardware domain

[Julien Grall]

Hi Oleksandr,

On 09/12/2021 07:29, Oleksandr Andrushchenko wrote:
> +unsigned int domain_vpci_get_num_mmio_handlers(struct domain *d)
> +{
> +    if ( !has_vpci(d) )
> +        return 0;
> +
> +    if ( is_hardware_domain(d) )
> +    {
> +        int ret = pci_host_iterate_bridges_and_count(d, vpci_get_num_handlers_cb);
> +
> +        return ret < 0 ? 0 : ret;

Sorry I only spotted this now. AFAICT, ret is not meant to return ret < 
0 in this case. But if it were then I think it would be wrong to 
continue as nothing happened because the code will likely fall 
over/crash when registering the I/O handlers.

I would document this oddity with

if ( ret < 0 )
{
    ASSERT_UNREACHABLE();
    return 0;
}

I can do the change on commit if the others are happy with it.

Cheers,

-- 
Julien Grall

Re: [PATCH v8 2/4] xen/arm: setup MMIO range trap handlers for hardware domain

[Oleksandr Andrushchenko]

Hi, Julien!

On 10.12.21 19:52, Julien Grall wrote:
> Hi Oleksandr,
>
> On 09/12/2021 07:29, Oleksandr Andrushchenko wrote:
>> +unsigned int domain_vpci_get_num_mmio_handlers(struct domain *d)
>> +{
>> +    if ( !has_vpci(d) )
>> +        return 0;
>> +
>> +    if ( is_hardware_domain(d) )
>> +    {
>> +        int ret = pci_host_iterate_bridges_and_count(d, vpci_get_num_handlers_cb);
>> +
>> +        return ret < 0 ? 0 : ret;
>
> Sorry I only spotted this now. AFAICT, ret is not meant to return ret < 0 in this case. But if it were then I think it would be wrong to continue as nothing happened because the code will likely fall over/crash when registering the I/O handlers.
>
> I would document this oddity with
>
> if ( ret < 0 )
> {
>    ASSERT_UNREACHABLE();
>    return 0;
> }
>
> I can do the change on commit if the others are happy with it.
Yes, please, do me a favor
>
> Cheers,
>
Thank you,
Oleksandr

Re: [PATCH v8 2/4] xen/arm: setup MMIO range trap handlers for hardware domain

[Julien Grall]

On 10/12/2021 18:37, Oleksandr Andrushchenko wrote:
> Hi, Julien!

Hello,

> On 10.12.21 19:52, Julien Grall wrote:
>> Hi Oleksandr,
>>
>> On 09/12/2021 07:29, Oleksandr Andrushchenko wrote:
>>> +unsigned int domain_vpci_get_num_mmio_handlers(struct domain *d)
>>> +{
>>> +    if ( !has_vpci(d) )
>>> +        return 0;
>>> +
>>> +    if ( is_hardware_domain(d) )
>>> +    {
>>> +        int ret = pci_host_iterate_bridges_and_count(d, vpci_get_num_handlers_cb);
>>> +
>>> +        return ret < 0 ? 0 : ret;
>>
>> Sorry I only spotted this now. AFAICT, ret is not meant to return ret < 0 in this case. But if it were then I think it would be wrong to continue as nothing happened because the code will likely fall over/crash when registering the I/O handlers.
>>
>> I would document this oddity with
>>
>> if ( ret < 0 )
>> {
>>     ASSERT_UNREACHABLE();
>>     return 0;
>> }
>>
>> I can do the change on commit if the others are happy with it.
> Yes, please, do me a favor

Ok. With that:

Acked-by: Julien Grall <jgrall@amazon.com>

Cheers,

>>
>> Cheers,
>>
> Thank you,
> Oleksandr

-- 
Julien Grall

Re: [PATCH v8 0/4] PCI devices passthrough on Arm, part 2

[Julien Grall]

On 09/12/2021 07:29, Oleksandr Andrushchenko wrote:
> From: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com>
> 
> Hi, all!

Hi Oleksandr,

> This is an assorted series of patches which aim is to make some further
> basis for PCI passthrough on Arm support. The series continues the work
> published earlier by Arm [1] and adds new helpers and clears the way for
> vPCI changes which will follow.
> 
> RFC is at [2], [3]. Design presentation can be found at [4].Hi
> 
> I have removed patch
> [PATCH v6 5/7] xen/arm: do not map IRQs and memory for disabled devices
> as it seems that this needs more time for decision on how to achive
> that.
> 
> I have also added a new patch
> [PATCH v7 4/7] xen/arm: account IO handler for emulated PCI host bridge
> with a tiny latent bug fix.
> 
> This series contains all the patches which are left un-committed yet.
> 
> Thank you,
> Oleksandr
> 
> [1] https://patchwork.kernel.org/project/xen-devel/list/?series=558681
> [2] https://lists.xenproject.org/archives/html/xen-devel/2020-07/msg01184.html
> [3] https://lists.xenproject.org/archives/html/xen-devel/2020-07/threads.html#01184
> [4] https://static.sched.com/hosted_files/xen2021/e4/PCI_Device_Passthrough_On_Arm.pdf
> 
> Oleksandr Andrushchenko (4):
>    xen/arm: add pci-domain for disabled devices
>    xen/arm: setup MMIO range trap handlers for hardware domain
>    xen/arm: account IO handler for emulated PCI host bridge
>    xen/arm: do not map PCI ECAM and MMIO space to Domain-0's p2m
> 
>   xen/arch/arm/domain.c              |   2 +
>   xen/arch/arm/domain_build.c        | 132 ++++++++++++++++++++---------
>   xen/arch/arm/pci/ecam.c            |  14 +++
>   xen/arch/arm/pci/pci-host-common.c |  77 ++++++++++++++++-
>   xen/arch/arm/pci/pci-host-zynqmp.c |   1 +
>   xen/arch/arm/vpci.c                |  85 ++++++++++++++++---
>   xen/arch/arm/vpci.h                |   6 ++
>   xen/include/asm-arm/pci.h          |  22 +++++
>   xen/include/asm-arm/setup.h        |  13 +++

As a FYI, Jan pushed today a commit that moved the headers from 
xen/include/asm-arm to xen/arch/arm/include/asm/.

I have handled the clash for this series while committing.

Thank you for the contribution.

Cheers,

-- 
Julien Grall

Re: [PATCH v8 0/4] PCI devices passthrough on Arm, part 2

[Oleksandr Andrushchenko]

Hi, Julien!

On 15.12.21 19:48, Julien Grall wrote:
> On 09/12/2021 07:29, Oleksandr Andrushchenko wrote:
>> From: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com>
>>
>> Hi, all!
>
> Hi Oleksandr,
>
>> This is an assorted series of patches which aim is to make some further
>> basis for PCI passthrough on Arm support. The series continues the work
>> published earlier by Arm [1] and adds new helpers and clears the way for
>> vPCI changes which will follow.
>>
>> RFC is at [2], [3]. Design presentation can be found at [4].Hi
>>
>> I have removed patch
>> [PATCH v6 5/7] xen/arm: do not map IRQs and memory for disabled devices
>> as it seems that this needs more time for decision on how to achive
>> that.
>>
>> I have also added a new patch
>> [PATCH v7 4/7] xen/arm: account IO handler for emulated PCI host bridge
>> with a tiny latent bug fix.
>>
>> This series contains all the patches which are left un-committed yet.
>>
>> Thank you,
>> Oleksandr
>>
>> [1] https://urldefense.com/v3/__https://patchwork.kernel.org/project/xen-devel/list/?series=558681__;!!GF_29dbcQIUBPA!gqz5e3dL-6UrscJs6ZorKgDOMpYsfiPNFn0ffortKrcGBkil9SMKjbDcX7V_T9RVID_vrU1iUA$ [patchwork[.]kernel[.]org]
>> [2] https://urldefense.com/v3/__https://lists.xenproject.org/archives/html/xen-devel/2020-07/msg01184.html__;!!GF_29dbcQIUBPA!gqz5e3dL-6UrscJs6ZorKgDOMpYsfiPNFn0ffortKrcGBkil9SMKjbDcX7V_T9RVID-GAYv29Q$ [lists[.]xenproject[.]org]
>> [3] https://urldefense.com/v3/__https://lists.xenproject.org/archives/html/xen-devel/2020-07/threads.html*01184__;Iw!!GF_29dbcQIUBPA!gqz5e3dL-6UrscJs6ZorKgDOMpYsfiPNFn0ffortKrcGBkil9SMKjbDcX7V_T9RVID_PWk-hRA$ [lists[.]xenproject[.]org]
>> [4] https://urldefense.com/v3/__https://static.sched.com/hosted_files/xen2021/e4/PCI_Device_Passthrough_On_Arm.pdf__;!!GF_29dbcQIUBPA!gqz5e3dL-6UrscJs6ZorKgDOMpYsfiPNFn0ffortKrcGBkil9SMKjbDcX7V_T9RVID9SzhK4bw$ [static[.]sched[.]com]
>>
>> Oleksandr Andrushchenko (4):
>>    xen/arm: add pci-domain for disabled devices
>>    xen/arm: setup MMIO range trap handlers for hardware domain
>>    xen/arm: account IO handler for emulated PCI host bridge
>>    xen/arm: do not map PCI ECAM and MMIO space to Domain-0's p2m
>>
>>   xen/arch/arm/domain.c              |   2 +
>>   xen/arch/arm/domain_build.c        | 132 ++++++++++++++++++++---------
>>   xen/arch/arm/pci/ecam.c            |  14 +++
>>   xen/arch/arm/pci/pci-host-common.c |  77 ++++++++++++++++-
>>   xen/arch/arm/pci/pci-host-zynqmp.c |   1 +
>>   xen/arch/arm/vpci.c                |  85 ++++++++++++++++---
>>   xen/arch/arm/vpci.h                |   6 ++
>>   xen/include/asm-arm/pci.h          |  22 +++++
>>   xen/include/asm-arm/setup.h        |  13 +++
>
> As a FYI, Jan pushed today a commit that moved the headers from xen/include/asm-arm to xen/arch/arm/include/asm/.
>
> I have handled the clash for this series while committing.
Thank you for doing that!
>
> Thank you for the contribution.
Thank you all for supporting this work!
Oleksandr
>
> Cheers,
>