diff mbox series

[v2,5/5] xen/arm: ffa: Enable VM to VM without firmware

Message ID 400fdd82de6e61e8e7598a120bb0bbe2c354ab72.1741617888.git.bertrand.marquis@arm.com (mailing list archive)
State New
Headers show
Series FF-A VM to VM support | expand

Commit Message

Bertrand Marquis March 10, 2025, 2:50 p.m. UTC
When VM to VM support is activated and there is no suitable FF-A support
in the firmware, enable FF-A support for VMs to allow using it for VM to
VM communications.
If there is Optee running in the secure world and using the non FF-A
communication system, having CONFIG_FFA_VM_TO_VM could be non functional
(if optee is probed first) or Optee could be non functional (if FF-A is
probed first) so it is not recommended to activate the configuration
option for such systems.

To make buffer full notification work between VMs when there is not
firmware, rework the notification handling and modify the global flag to
only be used as check for firmware notification support instead.

Modify part_info_get to return the list of VMs when there is no firmware
support.

Signed-off-by: Bertrand Marquis <bertrand.marquis@arm.com>
---
Changes in v2:
- replace ifdef with IS_ENABLED when possible
---
 xen/arch/arm/tee/ffa.c          |  12 +++-
 xen/arch/arm/tee/ffa_notif.c    | 114 ++++++++++++++++----------------
 xen/arch/arm/tee/ffa_partinfo.c |   3 +-
 3 files changed, 69 insertions(+), 60 deletions(-)
diff mbox series

Patch

diff --git a/xen/arch/arm/tee/ffa.c b/xen/arch/arm/tee/ffa.c
index 3bbdd7168a6b..f6582d2e855a 100644
--- a/xen/arch/arm/tee/ffa.c
+++ b/xen/arch/arm/tee/ffa.c
@@ -324,8 +324,9 @@  static int ffa_domain_init(struct domain *d)
     struct ffa_ctx *ctx;
     int ret;
 
-    if ( !ffa_fw_version )
+    if ( !IS_ENABLED(CONFIG_FFA_VM_TO_VM) && !ffa_fw_version )
         return -ENODEV;
+
     /*
      * We are using the domain_id + 1 as the FF-A ID for VMs as FF-A ID 0 is
      * reserved for the hypervisor and we only support secure endpoints using
@@ -549,6 +550,15 @@  err_no_fw:
     bitmap_zero(ffa_fw_abi_supported, FFA_ABI_BITMAP_SIZE);
     printk(XENLOG_WARNING "ARM FF-A No firmware support\n");
 
+    if ( IS_ENABLED(CONFIG_FFA_VM_TO_VM) )
+    {
+        INIT_LIST_HEAD(&ffa_teardown_head);
+        init_timer(&ffa_teardown_timer, ffa_teardown_timer_callback, NULL, 0);
+
+        printk(XENLOG_INFO "ARM FF-A only available between VMs\n");
+        return true;
+    }
+
     return false;
 }
 
diff --git a/xen/arch/arm/tee/ffa_notif.c b/xen/arch/arm/tee/ffa_notif.c
index d19aa5c5bef6..0673e53a9def 100644
--- a/xen/arch/arm/tee/ffa_notif.c
+++ b/xen/arch/arm/tee/ffa_notif.c
@@ -16,7 +16,7 @@ 
 
 #include "ffa_private.h"
 
-static bool __ro_after_init notif_enabled;
+static bool __ro_after_init fw_notif_enabled;
 static unsigned int __ro_after_init notif_sri_irq;
 
 int ffa_handle_notification_bind(struct cpu_user_regs *regs)
@@ -27,21 +27,17 @@  int ffa_handle_notification_bind(struct cpu_user_regs *regs)
     uint32_t bitmap_lo = get_user_reg(regs, 3);
     uint32_t bitmap_hi = get_user_reg(regs, 4);
 
-    if ( !notif_enabled )
-        return FFA_RET_NOT_SUPPORTED;
-
     if ( (src_dst & 0xFFFFU) != ffa_get_vm_id(d) )
         return FFA_RET_INVALID_PARAMETERS;
 
     if ( flags )    /* Only global notifications are supported */
         return FFA_RET_DENIED;
 
-    /*
-     * We only support notifications from SP so no need to check the sender
-     * endpoint ID, the SPMC will take care of that for us.
-     */
-    return ffa_simple_call(FFA_NOTIFICATION_BIND, src_dst, flags, bitmap_lo,
-                           bitmap_hi);
+    if ( FFA_ID_IS_SECURE(src_dst>>16) && fw_notif_enabled )
+        return ffa_simple_call(FFA_NOTIFICATION_BIND, src_dst, flags,
+                               bitmap_lo, bitmap_hi);
+
+    return FFA_RET_NOT_SUPPORTED;
 }
 
 int ffa_handle_notification_unbind(struct cpu_user_regs *regs)
@@ -51,32 +47,34 @@  int ffa_handle_notification_unbind(struct cpu_user_regs *regs)
     uint32_t bitmap_lo = get_user_reg(regs, 3);
     uint32_t bitmap_hi = get_user_reg(regs, 4);
 
-    if ( !notif_enabled )
-        return FFA_RET_NOT_SUPPORTED;
-
     if ( (src_dst & 0xFFFFU) != ffa_get_vm_id(d) )
         return FFA_RET_INVALID_PARAMETERS;
 
-    /*
-     * We only support notifications from SP so no need to check the
-     * destination endpoint ID, the SPMC will take care of that for us.
-     */
-    return  ffa_simple_call(FFA_NOTIFICATION_UNBIND, src_dst, 0, bitmap_lo,
-                            bitmap_hi);
+    if ( FFA_ID_IS_SECURE(src_dst>>16) && fw_notif_enabled )
+        return  ffa_simple_call(FFA_NOTIFICATION_UNBIND, src_dst, 0, bitmap_lo,
+                                bitmap_hi);
+
+    return FFA_RET_NOT_SUPPORTED;
 }
 
 void ffa_handle_notification_info_get(struct cpu_user_regs *regs)
 {
     struct domain *d = current->domain;
     struct ffa_ctx *ctx = d->arch.tee;
+    bool notif_pending = false;
 
-    if ( !notif_enabled )
+    if ( !IS_ENABLED(CONFIG_FFA_VM_TO_VM) && !fw_notif_enabled )
     {
         ffa_set_regs_error(regs, FFA_RET_NOT_SUPPORTED);
         return;
     }
 
-    if ( test_and_clear_bool(ctx->notif.secure_pending) )
+    notif_pending = ctx->notif.secure_pending;
+#ifdef CONFIG_FFA_VM_TO_VM
+    notif_pending |= ctx->notif.buff_full_pending;
+#endif
+
+    if ( notif_pending )
     {
         /* A pending global notification for the guest */
         ffa_set_regs(regs, FFA_SUCCESS_64, 0,
@@ -103,7 +101,7 @@  void ffa_handle_notification_get(struct cpu_user_regs *regs)
     uint32_t w6 = 0;
     uint32_t w7 = 0;
 
-    if ( !notif_enabled )
+    if ( !IS_ENABLED(CONFIG_FFA_VM_TO_VM) && !fw_notif_enabled )
     {
         ffa_set_regs_error(regs, FFA_RET_NOT_SUPPORTED);
         return;
@@ -115,7 +113,8 @@  void ffa_handle_notification_get(struct cpu_user_regs *regs)
         return;
     }
 
-    if ( flags & ( FFA_NOTIF_FLAG_BITMAP_SP | FFA_NOTIF_FLAG_BITMAP_SPM ) )
+    if ( fw_notif_enabled && (flags & ( FFA_NOTIF_FLAG_BITMAP_SP
+                                        | FFA_NOTIF_FLAG_BITMAP_SPM )) )
     {
         struct arm_smccc_1_2_regs arg = {
             .a0 = FFA_NOTIFICATION_GET,
@@ -170,15 +169,14 @@  int ffa_handle_notification_set(struct cpu_user_regs *regs)
     uint32_t bitmap_lo = get_user_reg(regs, 3);
     uint32_t bitmap_hi = get_user_reg(regs, 4);
 
-    if ( !notif_enabled )
-        return FFA_RET_NOT_SUPPORTED;
-
     if ( (src_dst >> 16) != ffa_get_vm_id(d) )
         return FFA_RET_INVALID_PARAMETERS;
 
-    /* Let the SPMC check the destination of the notification */
-    return ffa_simple_call(FFA_NOTIFICATION_SET, src_dst, flags, bitmap_lo,
-                           bitmap_hi);
+    if ( FFA_ID_IS_SECURE(src_dst>>16) && fw_notif_enabled )
+        return ffa_simple_call(FFA_NOTIFICATION_SET, src_dst, flags, bitmap_lo,
+                               bitmap_hi);
+
+    return FFA_RET_NOT_SUPPORTED;
 }
 
 #ifdef CONFIG_FFA_VM_TO_VM
@@ -190,7 +188,7 @@  void ffa_raise_rx_buffer_full(struct domain *d)
         return;
 
     if ( !test_and_set_bool(ctx->notif.buff_full_pending) )
-        vgic_inject_irq(d, d->vcpu[0], notif_sri_irq, true);
+        vgic_inject_irq(d, d->vcpu[0], GUEST_FFA_NOTIF_PEND_INTR_ID, true);
 }
 #endif
 
@@ -363,7 +361,7 @@  void ffa_notif_init_interrupt(void)
 {
     int ret;
 
-    if ( notif_enabled && notif_sri_irq < NR_GIC_SGI )
+    if ( fw_notif_enabled && notif_sri_irq < NR_GIC_SGI )
     {
         /*
          * An error here is unlikely since the primary CPU has already
@@ -394,41 +392,41 @@  void ffa_notif_init(void)
     int ret;
 
     /* Only enable fw notification if all ABIs we need are supported */
-    if ( !(ffa_fw_supports_fid(FFA_NOTIFICATION_BITMAP_CREATE) &&
-           ffa_fw_supports_fid(FFA_NOTIFICATION_BITMAP_DESTROY) &&
-           ffa_fw_supports_fid(FFA_NOTIFICATION_GET) &&
-           ffa_fw_supports_fid(FFA_NOTIFICATION_INFO_GET_64)) )
-        return;
-
-    arm_smccc_1_2_smc(&arg, &resp);
-    if ( resp.a0 != FFA_SUCCESS_32 )
-        return;
-
-    irq = resp.a2;
-    notif_sri_irq = irq;
-    if ( irq >= NR_GIC_SGI )
-        irq_set_type(irq, IRQ_TYPE_EDGE_RISING);
-    ret = request_irq(irq, 0, notif_irq_handler, "FF-A notif", NULL);
-    if ( ret )
+    if ( ffa_fw_supports_fid(FFA_NOTIFICATION_BITMAP_CREATE) &&
+         ffa_fw_supports_fid(FFA_NOTIFICATION_BITMAP_DESTROY) &&
+         ffa_fw_supports_fid(FFA_NOTIFICATION_GET) &&
+         ffa_fw_supports_fid(FFA_NOTIFICATION_INFO_GET_64) )
     {
-        printk(XENLOG_ERR "ffa: request_irq irq %u failed: error %d\n",
-               irq, ret);
-        return;
-    }
+        arm_smccc_1_2_smc(&arg, &resp);
+        if ( resp.a0 != FFA_SUCCESS_32 )
+            return;
 
-    notif_enabled = true;
+        irq = resp.a2;
+        notif_sri_irq = irq;
+        if ( irq >= NR_GIC_SGI )
+            irq_set_type(irq, IRQ_TYPE_EDGE_RISING);
+        ret = request_irq(irq, 0, notif_irq_handler, "FF-A notif", NULL);
+        if ( ret )
+        {
+            printk(XENLOG_ERR "ffa: request_irq irq %u failed: error %d\n",
+                   irq, ret);
+            return;
+        }
+        fw_notif_enabled = true;
+    }
 }
 
 int ffa_notif_domain_init(struct domain *d)
 {
     int32_t res;
 
-    if ( !notif_enabled )
-        return 0;
+    if ( fw_notif_enabled )
+    {
 
-    res = ffa_notification_bitmap_create(ffa_get_vm_id(d), d->max_vcpus);
-    if ( res )
-        return -ENOMEM;
+        res = ffa_notification_bitmap_create(ffa_get_vm_id(d), d->max_vcpus);
+        if ( res )
+            return -ENOMEM;
+    }
 
     return 0;
 }
@@ -439,6 +437,6 @@  void ffa_notif_domain_destroy(struct domain *d)
      * Call bitmap_destroy even if bitmap create failed as the SPMC will
      * return a DENIED error that we will ignore.
      */
-    if ( notif_enabled )
+    if ( fw_notif_enabled )
         ffa_notification_bitmap_destroy(ffa_get_vm_id(d));
 }
diff --git a/xen/arch/arm/tee/ffa_partinfo.c b/xen/arch/arm/tee/ffa_partinfo.c
index 7af1eca2d0c4..291396c8f635 100644
--- a/xen/arch/arm/tee/ffa_partinfo.c
+++ b/xen/arch/arm/tee/ffa_partinfo.c
@@ -130,7 +130,8 @@  void ffa_handle_partition_info_get(struct cpu_user_regs *regs)
         goto out;
     }
 
-    if ( !ffa_fw_supports_fid(FFA_PARTITION_INFO_GET) )
+    if ( !IS_ENABLED(CONFIG_FFA_VM_TO_VM) &&
+         !ffa_fw_supports_fid(FFA_PARTITION_INFO_GET) )
     {
         /* Just give an empty partition list to the caller */
         ret = FFA_RET_OK;