Add support for FF-A notifications, currently limited to an SP (Secure
Partition) sending an asynchronous notification to a guest.
Guests and Xen itself are made aware of pending notifications with an
interrupt. The interrupt handler retrieves the notifications using the
FF-A ABI and deliver them to their destinations.
Signed-off-by: Jens Wiklander <jens.wiklan...@linaro.org>
---
xen/arch/arm/tee/Makefile | 1 +
xen/arch/arm/tee/ffa.c | 58 ++++++
xen/arch/arm/tee/ffa_notif.c | 319 +++++++++++++++++++++++++++++++++
xen/arch/arm/tee/ffa_private.h | 71 ++++++++
4 files changed, 449 insertions(+)
create mode 100644 xen/arch/arm/tee/ffa_notif.c
diff --git a/xen/arch/arm/tee/Makefile b/xen/arch/arm/tee/Makefile
index f0112a2f922d..7c0f46f7f446 100644
--- a/xen/arch/arm/tee/Makefile
+++ b/xen/arch/arm/tee/Makefile
@@ -2,5 +2,6 @@ obj-$(CONFIG_FFA) += ffa.o
obj-$(CONFIG_FFA) += ffa_shm.o
obj-$(CONFIG_FFA) += ffa_partinfo.o
obj-$(CONFIG_FFA) += ffa_rxtx.o
+obj-$(CONFIG_FFA) += ffa_notif.o
obj-y += tee.o
obj-$(CONFIG_OPTEE) += optee.o
diff --git a/xen/arch/arm/tee/ffa.c b/xen/arch/arm/tee/ffa.c
index 5209612963e1..ce9757bfeed1 100644
--- a/xen/arch/arm/tee/ffa.c
+++ b/xen/arch/arm/tee/ffa.c
@@ -39,6 +39,9 @@
* - at most 32 shared memory regions per guest
* o FFA_MSG_SEND_DIRECT_REQ:
* - only supported from a VM to an SP
+ * o FFA_NOTIFICATION_*:
+ * - only supports global notifications, that is, per vCPU notifications
+ * are not supported
*
* There are some large locked sections with ffa_tx_buffer_lock and
* ffa_rx_buffer_lock. Especially the ffa_tx_buffer_lock spinlock used
@@ -194,6 +197,8 @@ out:
static void handle_features(struct cpu_user_regs *regs)
{
+ struct domain *d = current->domain;
+ struct ffa_ctx *ctx = d->arch.tee;
uint32_t a1 = get_user_reg(regs, 1);
unsigned int n;
@@ -240,6 +245,30 @@ static void handle_features(struct cpu_user_regs *regs)
BUILD_BUG_ON(PAGE_SIZE != FFA_PAGE_SIZE);
ffa_set_regs_success(regs, 0, 0);
break;
+ case FFA_FEATURE_NOTIF_PEND_INTR:
+ if ( ctx->notif.enabled )
+ ffa_set_regs_success(regs, FFA_NOTIF_PEND_INTR_ID, 0);
+ else
+ ffa_set_regs_error(regs, FFA_RET_NOT_SUPPORTED);
+ break;
+ case FFA_FEATURE_SCHEDULE_RECV_INTR:
+ if ( ctx->notif.enabled )
+ ffa_set_regs_success(regs, FFA_NOTIF_PEND_INTR_ID, 0);
+ else
+ ffa_set_regs_error(regs, FFA_RET_NOT_SUPPORTED);
+ break;
+
+ case FFA_NOTIFICATION_BIND:
+ case FFA_NOTIFICATION_UNBIND:
+ case FFA_NOTIFICATION_GET:
+ case FFA_NOTIFICATION_SET:
+ case FFA_NOTIFICATION_INFO_GET_32:
+ case FFA_NOTIFICATION_INFO_GET_64:
+ if ( ctx->notif.enabled )
+ ffa_set_regs_success(regs, 0, 0);
+ else
+ ffa_set_regs_error(regs, FFA_RET_NOT_SUPPORTED);
+ break;
default:
ffa_set_regs_error(regs, FFA_RET_NOT_SUPPORTED);
break;
@@ -305,6 +334,30 @@ static bool ffa_handle_call(struct cpu_user_regs *regs)
get_user_reg(regs, 1)),
get_user_reg(regs, 3));
break;
+ case FFA_NOTIFICATION_BIND:
+ e = ffa_handle_notification_bind(get_user_reg(regs, 1),
+ get_user_reg(regs, 2),
+ get_user_reg(regs, 3),
+ get_user_reg(regs, 4));
+ break;
+ case FFA_NOTIFICATION_UNBIND:
+ e = ffa_handle_notification_unbind(get_user_reg(regs, 1),
+ get_user_reg(regs, 3),
+ get_user_reg(regs, 4));
+ break;
+ case FFA_NOTIFICATION_INFO_GET_32:
+ case FFA_NOTIFICATION_INFO_GET_64:
+ ffa_handle_notification_info_get(regs);
+ return true;
+ case FFA_NOTIFICATION_GET:
+ ffa_handle_notification_get(regs);
+ return true;
+ case FFA_NOTIFICATION_SET:
+ e = ffa_handle_notification_set(get_user_reg(regs, 1),
+ get_user_reg(regs, 2),
+ get_user_reg(regs, 3),
+ get_user_reg(regs, 4));
+ break;
default:
gprintk(XENLOG_ERR, "ffa: unhandled fid 0x%x\n", fid);
@@ -348,6 +401,9 @@ static int ffa_domain_init(struct domain *d)
if ( !ffa_partinfo_domain_init(d) )
return -EIO;
+ if ( !ffa_notif_domain_init(d) )
+ return -ENOMEM;
+
return 0;
}
@@ -423,6 +479,7 @@ static int ffa_domain_teardown(struct domain *d)
return 0;
ffa_rxtx_domain_destroy(d);
+ ffa_notif_domain_destroy(d);
ffa_domain_teardown_continue(ctx, true /* first_time */);
@@ -502,6 +559,7 @@ static bool ffa_probe(void)
if ( !ffa_partinfo_init() )
goto err_rxtx_destroy;
+ ffa_notif_init();
INIT_LIST_HEAD(&ffa_teardown_head);
init_timer(&ffa_teardown_timer, ffa_teardown_timer_callback, NULL, 0);
diff --git a/xen/arch/arm/tee/ffa_notif.c b/xen/arch/arm/tee/ffa_notif.c
new file mode 100644
index 000000000000..0173ee515362
--- /dev/null
+++ b/xen/arch/arm/tee/ffa_notif.c
@@ -0,0 +1,319 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Copyright (C) 2024 Linaro Limited
+ */
+
+#include <xen/const.h>
+#include <xen/list.h>
+#include <xen/spinlock.h>
+#include <xen/types.h>
+
+#include <asm/smccc.h>
+#include <asm/regs.h>
+
+#include "ffa_private.h"
+
+static bool __ro_after_init notif_enabled;
+
+int ffa_handle_notification_bind(uint32_t src_dst, uint32_t flags,
+ uint32_t bitmap_lo, uint32_t bitmap_hi)
+{
+ struct domain *d = current->domain;
+
+ if ( !notif_enabled )
+ return FFA_RET_NOT_SUPPORTED;
+
+ if ( (src_dst & 0xffff) != 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_hi,
+ bitmap_lo);
+}
+
+int ffa_handle_notification_unbind(uint32_t src_dst, uint32_t bitmap_lo,
+ uint32_t bitmap_hi)
+{
+ struct domain *d = current->domain;
+
+ if ( !notif_enabled )
+ return FFA_RET_NOT_SUPPORTED;
+
+ if ( (src_dst & 0xffff) != 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_hi,
+ bitmap_lo);
+}
+
+void ffa_handle_notification_info_get(struct cpu_user_regs *regs)
+{
+ struct domain *d = current->domain;
+ struct ffa_ctx *ctx = d->arch.tee;
+ bool pending_global;
+
+ if ( !notif_enabled )
+ {
+ ffa_set_regs_error(regs, FFA_RET_NOT_SUPPORTED);
+ return;
+ }
+
+ spin_lock(&ctx->notif.lock);
+ pending_global = ctx->notif.secure_pending;
+ ctx->notif.secure_pending = false;
+ spin_unlock(&ctx->notif.lock);
+
+ if ( pending_global )
+ {
+ /* A pending global notification for the guest */
+ ffa_set_regs(regs, FFA_SUCCESS_64, 0,
+ 1U << FFA_NOTIF_INFO_GET_ID_COUNT_SHIFT, ffa_get_vm_id(d),
+ 0, 0, 0, 0);
+ }
+ else
+ {
+ /* Report an error if there where no pending global notification */
+ ffa_set_regs_error(regs, FFA_RET_NO_DATA);
+ }
+}
+
+void ffa_handle_notification_get(struct cpu_user_regs *regs)
+{
+ struct domain *d = current->domain;
+ uint32_t recv = get_user_reg(regs, 1);
+ uint32_t flags = get_user_reg(regs, 2);
+ uint32_t w2 = 0;
+ uint32_t w3 = 0;
+ uint32_t w4 = 0;
+ uint32_t w5 = 0;
+ uint32_t w6 = 0;
+ uint32_t w7 = 0;
+
+ if ( !notif_enabled )
+ {
+ ffa_set_regs_error(regs, FFA_RET_NOT_SUPPORTED);
+ return;
+ }
+
+ if ( (recv & 0xffff) != ffa_get_vm_id(d) )
+ {
+ ffa_set_regs_error(regs, FFA_RET_INVALID_PARAMETERS);
+ return;
+ }
+
+ if ( flags & ( FFA_NOTIF_FLAG_BITMAP_SP | FFA_NOTIF_FLAG_BITMAP_SPM ) )
+ {
+ struct arm_smccc_1_2_regs arg = {
+ .a0 = FFA_NOTIFICATION_GET,
+ .a1 = recv,
+ .a2 = flags & ( FFA_NOTIF_FLAG_BITMAP_SP |
+ FFA_NOTIF_FLAG_BITMAP_SPM ),
+ };
+ struct arm_smccc_1_2_regs resp;
+ int32_t e;
+
+ arm_smccc_1_2_smc(&arg, &resp);
+ e = ffa_get_ret_code(&resp);
+ if ( e )
+ {
+ ffa_set_regs_error(regs, e);
+ return;
+ }
+
+ if ( flags & FFA_NOTIF_FLAG_BITMAP_SP )
+ {
+ w2 = resp.a2;
+ w3 = resp.a3;
+ }
+
+ if ( flags & FFA_NOTIF_FLAG_BITMAP_SPM )
+ w6 = resp.a6;
+ }
+
+ ffa_set_regs(regs, FFA_SUCCESS_32, 0, w2, w3, w4, w5, w6, w7);
+}
+
+int ffa_handle_notification_set(uint32_t src_dst, uint32_t flags,
+ uint32_t bitmap_lo, uint32_t bitmap_hi)
+{
+ struct domain *d = current->domain;
+
+ if ( !notif_enabled )
+ return FFA_RET_NOT_SUPPORTED;
+
+ if ( (src_dst >> 16) != ffa_get_vm_id(d) )
+ return FFA_RET_INVALID_PARAMETERS;
+
+ /*
+ * 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_SET, src_dst, flags, bitmap_lo,
+ bitmap_hi);
+}
+
+static uint16_t get_id_from_resp(struct arm_smccc_1_2_regs *resp,
+ unsigned int n)
+{
+ unsigned int ids_per_reg;
+ unsigned int reg_idx;
+ unsigned int reg_shift;
+
+ if ( smccc_is_conv_64(resp->a0) )
+ ids_per_reg = 4;
+ else
+ ids_per_reg = 2;
+
+ reg_idx = n / ids_per_reg + 3;
+ reg_shift = ( n % ids_per_reg ) * 16;
+
+ switch ( reg_idx )
+ {
+ case 3:
+ return resp->a3 >> reg_shift;
+ case 4:
+ return resp->a4 >> reg_shift;
+ case 5:
+ return resp->a5 >> reg_shift;
+ case 6:
+ return resp->a6 >> reg_shift;
+ case 7:
+ return resp->a7 >> reg_shift;
+ default:
+ ASSERT(0); /* "Can't happen" */
+ return 0;
+ }
+}
+
+static void notif_irq_handler(int irq, void *data)
+{
+ const struct arm_smccc_1_2_regs arg = {
+ .a0 = FFA_NOTIFICATION_INFO_GET_64,
+ };
+ struct arm_smccc_1_2_regs resp;
+ unsigned int id_pos;
+ unsigned int list_count;
+ uint64_t ids_count;
+ unsigned int n;
+ int32_t res;
+
+ do {
+ arm_smccc_1_2_smc(&arg, &resp);
+ res = ffa_get_ret_code(&resp);
+ if ( res )
+ {
+ if ( res != FFA_RET_NO_DATA )
+ printk(XENLOG_ERR "ffa: notification info get failed: error
%d\n",
+ res);
+ return;
+ }
+
+ ids_count = resp.a2 >> FFA_NOTIF_INFO_GET_ID_LIST_SHIFT;
+ list_count = ( resp.a2 >> FFA_NOTIF_INFO_GET_ID_COUNT_SHIFT ) &
+ FFA_NOTIF_INFO_GET_ID_COUNT_MASK;
+
+ id_pos = 0;
+ for ( n = 0; n < list_count; n++ )
+ {
+ unsigned int count = ((ids_count >> 2 * n) & 0x3) + 1;
+ struct domain *d;
+
+ d = ffa_get_domain_by_vm_id(get_id_from_resp(&resp, id_pos));
+
+ if ( d )
+ {
+ struct ffa_ctx *ctx = d->arch.tee;
+
+ spin_lock(&ctx->notif.lock);
+ ctx->notif.secure_pending = true;
+ spin_unlock(&ctx->notif.lock);
+
+ /*
+ * Since we're only delivering global notification, always
+ * deliver to the first vCPU. It doesn't matter which we
+ * chose, as long as it's available.
+ */
+ vgic_inject_irq(d, d->vcpu[0], FFA_NOTIF_PEND_INTR_ID, true);
+
+ put_domain(d);
+ }
+
+ id_pos += count;
+ }
+
+ } while (resp.a2 & FFA_NOTIF_INFO_GET_MORE_FLAG);
+}
+
+static int32_t ffa_notification_bitmap_create(uint16_t vm_id,
+ uint32_t vcpu_count)
+{
+ return ffa_simple_call(FFA_NOTIFICATION_BITMAP_CREATE, vm_id, vcpu_count,
+ 0, 0);
+}
+
+static int32_t ffa_notification_bitmap_destroy(uint16_t vm_id)
+{
+ return ffa_simple_call(FFA_NOTIFICATION_BITMAP_DESTROY, vm_id, 0, 0, 0);
+}
+
+void ffa_notif_init(void)
+{
+ const struct arm_smccc_1_2_regs arg = {
+ .a0 = FFA_FEATURES,
+ .a1 = FFA_FEATURE_SCHEDULE_RECV_INTR,
+ };
+ struct arm_smccc_1_2_regs resp;
+ unsigned int irq;
+ int ret;
+
+ arm_smccc_1_2_smc(&arg, &resp);
+ if ( resp.a0 != FFA_SUCCESS_32 )
+ return;
+
+ irq = resp.a2;
+ 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);
+ notif_enabled = !ret;
+}
+
+bool ffa_notif_domain_init(struct domain *d)
+{
+ struct ffa_ctx *ctx = d->arch.tee;
+ int32_t res;
+
+ if ( !notif_enabled )
+ return true;
+
+ res = ffa_notification_bitmap_create(ffa_get_vm_id(d), d->max_vcpus);
+ if ( res )
+ return false;
+
+ ctx->notif.enabled = true;
+
+ return true;
+}
+
+void ffa_notif_domain_destroy(struct domain *d)
+{
+ struct ffa_ctx *ctx = d->arch.tee;
+
+ if ( ctx->notif.enabled )
+ {
+ ffa_notification_bitmap_destroy(ffa_get_vm_id(d));
+ ctx->notif.enabled = false;
+ }
+}
diff --git a/xen/arch/arm/tee/ffa_private.h b/xen/arch/arm/tee/ffa_private.h
index 98236cbf14a3..26c2af164d38 100644
--- a/xen/arch/arm/tee/ffa_private.h
+++ b/xen/arch/arm/tee/ffa_private.h
@@ -25,6 +25,7 @@
#define FFA_RET_DENIED -6
#define FFA_RET_RETRY -7
#define FFA_RET_ABORTED -8
+#define FFA_RET_NO_DATA -9
/* FFA_VERSION helpers */
#define FFA_VERSION_MAJOR_SHIFT 16U
@@ -60,6 +61,8 @@
*/
#define FFA_PAGE_SIZE SZ_4K
+#define FFA_NOTIF_BITMAP_SIZE 64
+
/*
* The number of pages used for each of the RX and TX buffers shared with
* the SPMC.
@@ -97,6 +100,18 @@
*/
#define FFA_MAX_SHM_COUNT 32
+/*
+ * TODO How to manage the available SGIs? SGI 8-15 seem to be entirely
+ * unused, but that may change.
+ *
+ * SGI is the preferred delivery mechanism. SGIs 8-15 are normally not used
+ * by a guest as they in a non-virtualized system typically are assigned to
+ * the secure world. Here we're free to use SGI 8-15 since they are virtual
+ * and have nothing to do with the secure world.
+ */
+#define FFA_NOTIF_PEND_INTR_ID 8
+#define FFA_SCHEDULE_RECV_INTR_ID 9
+
/*
* The time we wait until trying to tear down a domain again if it was
* blocked initially.
@@ -175,6 +190,21 @@
*/
#define FFA_PARTITION_INFO_GET_COUNT_FLAG BIT(0, U)
+/* Flags used in calls to FFA_NOTIFICATION_GET interface */
+#define FFA_NOTIF_FLAG_BITMAP_SP BIT(0, U)
+#define FFA_NOTIF_FLAG_BITMAP_VM BIT(1, U)
+#define FFA_NOTIF_FLAG_BITMAP_SPM BIT(2, U)
+#define FFA_NOTIF_FLAG_BITMAP_HYP BIT(3, U)
+
+#define FFA_NOTIF_INFO_GET_MORE_FLAG BIT(0, U)
+#define FFA_NOTIF_INFO_GET_ID_LIST_SHIFT 12
+#define FFA_NOTIF_INFO_GET_ID_COUNT_SHIFT 7
+#define FFA_NOTIF_INFO_GET_ID_COUNT_MASK 0x1F
+
+/* Feature IDs used with FFA_FEATURES */
+#define FFA_FEATURE_NOTIF_PEND_INTR 0x1U
+#define FFA_FEATURE_SCHEDULE_RECV_INTR 0x2U
+
/* Function IDs */
#define FFA_ERROR 0x84000060U
#define FFA_SUCCESS_32 0x84000061U
@@ -213,6 +243,27 @@
#define FFA_MEM_FRAG_TX 0x8400007BU
#define FFA_MSG_SEND 0x8400006EU
#define FFA_MSG_POLL 0x8400006AU
+#define FFA_NOTIFICATION_BITMAP_CREATE 0x8400007DU
+#define FFA_NOTIFICATION_BITMAP_DESTROY 0x8400007EU
+#define FFA_NOTIFICATION_BIND 0x8400007FU
+#define FFA_NOTIFICATION_UNBIND 0x84000080U
+#define FFA_NOTIFICATION_SET 0x84000081U
+#define FFA_NOTIFICATION_GET 0x84000082U
+#define FFA_NOTIFICATION_INFO_GET_32 0x84000083U
+#define FFA_NOTIFICATION_INFO_GET_64 0xC4000083U
+
+struct ffa_ctx_notif {
+ bool enabled;
+
+ /* Used to serialize access to the rest of this struct */
+ spinlock_t lock;
+
+ /*
+ * True if domain is reported by FFA_NOTIFICATION_INFO_GET to have
+ * pending global notifications.
+ */
+ bool secure_pending;
+};
struct ffa_ctx {
void *rx;
@@ -228,6 +279,7 @@ struct ffa_ctx {
struct list_head shm_list;
/* Number of allocated shared memory object */
unsigned int shm_count;
+ struct ffa_ctx_notif notif;
/*
* tx_lock is used to serialize access to tx
* rx_lock is used to serialize access to rx
@@ -271,12 +323,31 @@ uint32_t ffa_handle_rxtx_map(uint32_t fid, register_t
tx_addr,
uint32_t ffa_handle_rxtx_unmap(void);
int32_t ffa_handle_rx_release(void);
+void ffa_notif_init(void);
+bool ffa_notif_domain_init(struct domain *d);
+void ffa_notif_domain_destroy(struct domain *d);
+
+int ffa_handle_notification_bind(uint32_t src_dst, uint32_t flags,
+ uint32_t bitmap_lo, uint32_t bitmap_hi);
+int ffa_handle_notification_unbind(uint32_t src_dst, uint32_t bitmap_lo,
+ uint32_t bitmap_hi);
+void ffa_handle_notification_info_get(struct cpu_user_regs *regs);
+void ffa_handle_notification_get(struct cpu_user_regs *regs);
+int ffa_handle_notification_set(uint32_t src_dst, uint32_t flags,
+ uint32_t bitmap_lo, uint32_t bitmap_hi);
+
static inline uint16_t ffa_get_vm_id(const struct domain *d)
{
/* +1 since 0 is reserved for the hypervisor in FF-A */
return d->domain_id + 1;
}
+static inline struct domain *ffa_get_domain_by_vm_id(uint16_t vm_id)
+{
+ /* -1 to match ffa_get_vm_id() */
+ return get_domain_by_id(vm_id - 1);
+}
+
static inline void ffa_set_regs(struct cpu_user_regs *regs, register_t v0,
register_t v1, register_t v2, register_t v3,
register_t v4, register_t v5, register_t v6,
--
2.34.1
