[PATCH v6 10/16] xen: arm: define guest virtual platform in API headers

[Ian Campbell <ian.campbell@citrix.com>]

The tools and the hypervisor need to agree on various aspects of the guest
environment, such as interrupt numbers, memory layout, initial register values
for registers which are implementation defined etc. Therefore move the
associated defines into the public interface headers, or create them as
necessary.

This just exposes the current de-facto standard guest layout, which may be
subject to change in the future. This deliberately does not make the guest
layout dynamic since there is currently no need.

These values should not be exposed to guests, they should find these things
out via device tree or should not be relying on implementation defined
defaults.

Various bits of the hypervisor needed to change to configure dom0 with the real
platform values while using the virtual platform configuration for guests.
Arrange for this where appropriate and plumb through as needed.

We also need to expose some 64-bit values (e.g. PSR_GUEST64_INIT) for the
benefit of 32 bit toolstacks building 64 bit guests.

Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Acked-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Acked-by: Julien Grall <julien.grall@linaro.org>
---
v5: IRQs are unsigned int.
v4: dropped a spurious aarch64 ifdef
    improved some comments and expand the commit message to clarify that this
    is just implementing the current static de-facto setup.
    put back PSR_GUEST32_INIT which disapeared somewhere along the line
---
 tools/libxc/xc_dom_arm.c        |    4 +--
 xen/arch/arm/domain.c           |    8 ++++--
 xen/arch/arm/domain_build.c     |   13 +++++----
 xen/arch/arm/gic.c              |   21 +++++++++-----
 xen/arch/arm/psci.c             |    2 +-
 xen/arch/arm/traps.c            |    2 +-
 xen/arch/arm/vtimer.c           |   13 ++++++---
 xen/include/asm-arm/domain.h    |    1 +
 xen/include/asm-arm/event.h     |    3 +-
 xen/include/asm-arm/gic.h       |    3 --
 xen/include/asm-arm/processor.h |    7 -----
 xen/include/asm-arm/psci.h      |    5 ----
 xen/include/public/arch-arm.h   |   58 +++++++++++++++++++++++++++++++--------
 13 files changed, 90 insertions(+), 50 deletions(-)

diff --git a/tools/libxc/xc_dom_arm.c b/tools/libxc/xc_dom_arm.c
index df59ffb..9f3fdd3 100644
--- a/tools/libxc/xc_dom_arm.c
+++ b/tools/libxc/xc_dom_arm.c
@@ -126,13 +126,13 @@ static int vcpu_arm(struct xc_dom_image *dom, void *ptr)
      */
     ctxt->user_regs.r2_usr = 0xffffffff;
 
-    ctxt->sctlr = /* #define SCTLR_BASE */0x00c50078;
+    ctxt->sctlr = SCTLR_GUEST_INIT;
 
     ctxt->ttbr0 = 0;
     ctxt->ttbr1 = 0;
     ctxt->ttbcr = 0; /* Defined Reset Value */
 
-    ctxt->user_regs.cpsr = PSR_ABT_MASK|PSR_FIQ_MASK|PSR_IRQ_MASK|PSR_MODE_SVC;
+    ctxt->user_regs.cpsr = PSR_GUEST32_INIT;
 
     ctxt->flags = VGCF_online;
 
diff --git a/xen/arch/arm/domain.c b/xen/arch/arm/domain.c
index 5ff7adf..2f57d01 100644
--- a/xen/arch/arm/domain.c
+++ b/xen/arch/arm/domain.c
@@ -461,7 +461,8 @@ int vcpu_initialise(struct vcpu *v)
     if ( is_idle_vcpu(v) )
         return rc;
 
-    v->arch.sctlr = SCTLR_BASE;
+    v->arch.sctlr = SCTLR_GUEST_INIT;
+
     /*
      * By default exposes an SMP system with AFF0 set to the VCPU ID
      * TODO: Handle multi-threading processor and cluster
@@ -525,6 +526,9 @@ int arch_domain_create(struct domain *d, unsigned int domcr_flags)
     if ( (rc = vcpu_domain_init(d)) != 0 )
         goto fail;
 
+    /* XXX dom0 needs more intelligent selection of PPI */
+    d->arch.evtchn_irq = GUEST_EVTCHN_PPI;
+
     /*
      * Virtual UART is only used by linux early printk and decompress code.
      * Only use it for dom0 because the linux kernel may not support
@@ -740,7 +744,7 @@ void vcpu_mark_events_pending(struct vcpu *v)
     if ( already_pending )
         return;
 
-    vgic_vcpu_inject_irq(v, VGIC_IRQ_EVTCHN_CALLBACK, 1);
+    vgic_vcpu_inject_irq(v, v->domain->arch.evtchn_irq, 1);
 }
 
 /*
diff --git a/xen/arch/arm/domain_build.c b/xen/arch/arm/domain_build.c
index 4014b0a..aa7e3d2 100644
--- a/xen/arch/arm/domain_build.c
+++ b/xen/arch/arm/domain_build.c
@@ -333,7 +333,8 @@ static int make_memory_node(const struct domain *d,
     return res;
 }
 
-static int make_hypervisor_node(void *fdt, const struct dt_device_node *parent)
+static int make_hypervisor_node(struct domain *d,
+                                void *fdt, const struct dt_device_node *parent)
 {
     const char compat[] =
         "xen,xen-"__stringify(XEN_VERSION)"."__stringify(XEN_SUBVERSION)"\0"
@@ -381,8 +382,8 @@ static int make_hypervisor_node(void *fdt, const struct dt_device_node *parent)
      *
      * TODO: Handle correctly the cpumask
      */
-    DPRINT("  Event channel interrupt to %u\n", VGIC_IRQ_EVTCHN_CALLBACK);
-    set_interrupt_ppi(intr, VGIC_IRQ_EVTCHN_CALLBACK, 0xf,
+    DPRINT("  Event channel interrupt to %u\n", d->arch.evtchn_irq);
+    set_interrupt_ppi(intr, d->arch.evtchn_irq, 0xf,
                    DT_IRQ_TYPE_LEVEL_LOW);
 
     res = fdt_property_interrupts(fdt, &intr, 1);
@@ -413,11 +414,11 @@ static int make_psci_node(void *fdt, const struct dt_device_node *parent)
     if ( res )
         return res;
 
-    res = fdt_property_cell(fdt, "cpu_off", __PSCI_cpu_off);
+    res = fdt_property_cell(fdt, "cpu_off", PSCI_cpu_off);
     if ( res )
         return res;
 
-    res = fdt_property_cell(fdt, "cpu_on", __PSCI_cpu_on);
+    res = fdt_property_cell(fdt, "cpu_on", PSCI_cpu_on);
     if ( res )
         return res;
 
@@ -855,7 +856,7 @@ static int handle_node(struct domain *d, struct kernel_info *kinfo,
 
     if ( np == dt_host )
     {
-        res = make_hypervisor_node(kinfo->fdt, np);
+        res = make_hypervisor_node(d, kinfo->fdt, np);
         if ( res )
             return res;
 
diff --git a/xen/arch/arm/gic.c b/xen/arch/arm/gic.c
index 74575cd..33c6b8d 100644
--- a/xen/arch/arm/gic.c
+++ b/xen/arch/arm/gic.c
@@ -717,7 +717,7 @@ int gic_events_need_delivery(void)
 void gic_inject(void)
 {
     if ( vcpu_info(current, evtchn_upcall_pending) )
-        vgic_vcpu_inject_irq(current, VGIC_IRQ_EVTCHN_CALLBACK, 1);
+        vgic_vcpu_inject_irq(current, current->domain->arch.evtchn_irq, 1);
 
     gic_restore_pending_irqs(current);
     if (!gic_events_need_delivery())
@@ -823,13 +823,20 @@ void gic_interrupt(struct cpu_user_regs *regs, int is_fiq)
 
 int gicv_setup(struct domain *d)
 {
-    /* TODO: Retrieve distributor and CPU guest base address from the
-     * guest DTS
-     * For the moment we use dom0 DTS
+    /*
+     * Domain 0 gets the hardware address.
+     * Guests get the virtual platform layout.
      */
-    d->arch.vgic.dbase = gic.dbase;
-    d->arch.vgic.cbase = gic.cbase;
-
+    if ( d == dom0 )
+    {
+        d->arch.vgic.dbase = gic.dbase;
+        d->arch.vgic.cbase = gic.cbase;
+    }
+    else
+    {
+        d->arch.vgic.dbase = GUEST_GICD_BASE;
+        d->arch.vgic.cbase = GUEST_GICC_BASE;
+    }
 
     d->arch.vgic.nr_lines = 0;
 
diff --git a/xen/arch/arm/psci.c b/xen/arch/arm/psci.c
index 6c3be47..c82884f 100644
--- a/xen/arch/arm/psci.c
+++ b/xen/arch/arm/psci.c
@@ -43,7 +43,7 @@ int do_psci_cpu_on(uint32_t vcpuid, register_t entry_point)
 
     memset(ctxt, 0, sizeof(*ctxt));
     ctxt->user_regs.pc64 = (u64) entry_point;
-    ctxt->sctlr = SCTLR_BASE;
+    ctxt->sctlr = SCTLR_GUEST_INIT;
     ctxt->ttbr0 = 0;
     ctxt->ttbr1 = 0;
     ctxt->ttbcr = 0; /* Defined Reset Value */
diff --git a/xen/arch/arm/traps.c b/xen/arch/arm/traps.c
index 10ee498..d39e2d4 100644
--- a/xen/arch/arm/traps.c
+++ b/xen/arch/arm/traps.c
@@ -867,7 +867,7 @@ typedef struct {
 } arm_psci_t;
 
 #define PSCI(_name, _nr_args)                                  \
-    [ __PSCI_ ## _name ] =  {                                  \
+    [ PSCI_ ## _name ] =  {                                    \
         .fn = (arm_psci_fn_t) &do_psci_ ## _name,              \
         .nr_args = _nr_args,                                   \
     }
diff --git a/xen/arch/arm/vtimer.c b/xen/arch/arm/vtimer.c
index d58a630..f323453 100644
--- a/xen/arch/arm/vtimer.c
+++ b/xen/arch/arm/vtimer.c
@@ -54,21 +54,26 @@ int vcpu_domain_init(struct domain *d)
 int vcpu_vtimer_init(struct vcpu *v)
 {
     struct vtimer *t = &v->arch.phys_timer;
+    bool_t d0 = (v->domain == dom0);
 
-    /* TODO: Retrieve physical and virtual timer IRQ from the guest
-     * DT. For the moment we use dom0 DT
+    /*
+     * Domain 0 uses the hardware interrupts, guests get the virtual platform.
      */
 
     init_timer(&t->timer, phys_timer_expired, t, v->processor);
     t->ctl = 0;
     t->cval = NOW();
-    t->irq = timer_dt_irq(TIMER_PHYS_NONSECURE_PPI)->irq;
+    t->irq = d0
+        ? timer_dt_irq(TIMER_PHYS_NONSECURE_PPI)->irq
+        : GUEST_TIMER_PHYS_NS_PPI;
     t->v = v;
 
     t = &v->arch.virt_timer;
     init_timer(&t->timer, virt_timer_expired, t, v->processor);
     t->ctl = 0;
-    t->irq = timer_dt_irq(TIMER_VIRT_PPI)->irq;
+    t->irq = d0
+        ? timer_dt_irq(TIMER_VIRT_PPI)->irq
+        : GUEST_TIMER_VIRT_PPI;
     t->v = v;
 
     return 0;
diff --git a/xen/include/asm-arm/domain.h b/xen/include/asm-arm/domain.h
index 67bfbbc..d5cae2e 100644
--- a/xen/include/asm-arm/domain.h
+++ b/xen/include/asm-arm/domain.h
@@ -112,6 +112,7 @@ struct arch_domain
         spinlock_t                  lock;
     } vuart;
 
+    unsigned int evtchn_irq;
 }  __cacheline_aligned;
 
 struct arch_vcpu
diff --git a/xen/include/asm-arm/event.h b/xen/include/asm-arm/event.h
index 04d854f..dd3ad13 100644
--- a/xen/include/asm-arm/event.h
+++ b/xen/include/asm-arm/event.h
@@ -15,7 +15,8 @@ static inline int vcpu_event_delivery_is_enabled(struct vcpu *v)
 
 static inline int local_events_need_delivery_nomask(void)
 {
-    struct pending_irq *p = irq_to_pending(current, VGIC_IRQ_EVTCHN_CALLBACK);
+    struct pending_irq *p = irq_to_pending(current,
+                                           current->domain->arch.evtchn_irq);
 
     /* XXX: if the first interrupt has already been delivered, we should
      * check whether any other interrupts with priority higher than the
diff --git a/xen/include/asm-arm/gic.h b/xen/include/asm-arm/gic.h
index 0a890be..41f0b3b 100644
--- a/xen/include/asm-arm/gic.h
+++ b/xen/include/asm-arm/gic.h
@@ -129,9 +129,6 @@
 #define GICH_LR_CPUID_SHIFT     9
 #define GICH_VTR_NRLRGS         0x3f
 
-/* XXX: write this into the DT */
-#define VGIC_IRQ_EVTCHN_CALLBACK 31
-
 #ifndef __ASSEMBLY__
 #include <xen/device_tree.h>
 
diff --git a/xen/include/asm-arm/processor.h b/xen/include/asm-arm/processor.h
index 5294421..3da3a3d 100644
--- a/xen/include/asm-arm/processor.h
+++ b/xen/include/asm-arm/processor.h
@@ -48,15 +48,8 @@
 #define SCTLR_A         (1<<1)
 #define SCTLR_M         (1<<0)
 
-#define SCTLR_BASE        0x00c50078
 #define HSCTLR_BASE       0x30c51878
 
-#define PSR_GUEST32_INIT  (PSR_ABT_MASK|PSR_FIQ_MASK|PSR_IRQ_MASK|PSR_MODE_SVC)
-
-#ifdef CONFIG_ARM_64
-#define PSR_GUEST64_INIT (PSR_ABT_MASK|PSR_FIQ_MASK|PSR_IRQ_MASK|PSR_MODE_EL1h)
-#endif
-
 /* HCR Hyp Configuration Register */
 #define HCR_RW          (1<<31) /* Register Width, ARM64 only */
 #define HCR_TGE         (1<<27) /* Trap General Exceptions */
diff --git a/xen/include/asm-arm/psci.h b/xen/include/asm-arm/psci.h
index fdba636..67d4c35 100644
--- a/xen/include/asm-arm/psci.h
+++ b/xen/include/asm-arm/psci.h
@@ -6,11 +6,6 @@
 #define PSCI_EINVAL  -2
 #define PSCI_DENIED  -3
 
-#define __PSCI_cpu_suspend 0
-#define __PSCI_cpu_off     1
-#define __PSCI_cpu_on      2
-#define __PSCI_migrate     3
-
 int do_psci_cpu_on(uint32_t vcpuid, register_t entry_point);
 int do_psci_cpu_off(uint32_t power_state);
 int do_psci_cpu_suspend(uint32_t power_state, register_t entry_point);
diff --git a/xen/include/public/arch-arm.h b/xen/include/public/arch-arm.h
index 1e8aeda..cb41ddc 100644
--- a/xen/include/public/arch-arm.h
+++ b/xen/include/public/arch-arm.h
@@ -302,8 +302,19 @@ typedef uint64_t xen_callback_t;
 
 #endif
 
+#if defined(__XEN__) || defined(__XEN_TOOLS__)
+
 /* PSR bits (CPSR, SPSR)*/
 
+#define PSR_THUMB       (1<<5)        /* Thumb Mode enable */
+#define PSR_FIQ_MASK    (1<<6)        /* Fast Interrupt mask */
+#define PSR_IRQ_MASK    (1<<7)        /* Interrupt mask */
+#define PSR_ABT_MASK    (1<<8)        /* Asynchronous Abort mask */
+#define PSR_BIG_ENDIAN  (1<<9)        /* arm32: Big Endian Mode */
+#define PSR_DBG_MASK    (1<<9)        /* arm64: Debug Exception mask */
+#define PSR_IT_MASK     (0x0600fc00)  /* Thumb If-Then Mask */
+#define PSR_JAZELLE     (1<<24)       /* Jazelle Mode */
+
 /* 32 bit modes */
 #define PSR_MODE_USR 0x10
 #define PSR_MODE_FIQ 0x11
@@ -316,7 +327,6 @@ typedef uint64_t xen_callback_t;
 #define PSR_MODE_SYS 0x1f
 
 /* 64 bit modes */
-#ifdef __aarch64__
 #define PSR_MODE_BIT  0x10 /* Set iff AArch32 */
 #define PSR_MODE_EL3h 0x0d
 #define PSR_MODE_EL3t 0x0c
@@ -325,18 +335,44 @@ typedef uint64_t xen_callback_t;
 #define PSR_MODE_EL1h 0x05
 #define PSR_MODE_EL1t 0x04
 #define PSR_MODE_EL0t 0x00
-#endif
 
-#define PSR_THUMB       (1<<5)        /* Thumb Mode enable */
-#define PSR_FIQ_MASK    (1<<6)        /* Fast Interrupt mask */
-#define PSR_IRQ_MASK    (1<<7)        /* Interrupt mask */
-#define PSR_ABT_MASK    (1<<8)        /* Asynchronous Abort mask */
-#define PSR_BIG_ENDIAN  (1<<9)        /* Big Endian Mode */
-#ifdef __aarch64__ /* For Aarch64 bit 9 is repurposed. */
-#define PSR_DBG_MASK    (1<<9)
+#define PSR_GUEST32_INIT  (PSR_ABT_MASK|PSR_FIQ_MASK|PSR_IRQ_MASK|PSR_MODE_SVC)
+#define PSR_GUEST64_INIT (PSR_ABT_MASK|PSR_FIQ_MASK|PSR_IRQ_MASK|PSR_MODE_EL1h)
+
+#define SCTLR_GUEST_INIT    0x00c50078
+
+/*
+ * Virtual machine platform (memory layout, interrupts)
+ *
+ * These are defined for consistency between the tools and the
+ * hypervisor. Guests must not rely on these hardcoded values but
+ * should instead use the FDT.
+ */
+
+/* Physical Address Space */
+#define GUEST_GICD_BASE   0x2c001000ULL
+#define GUEST_GICD_SIZE   0x1000ULL
+#define GUEST_GICC_BASE   0x2c002000ULL
+#define GUEST_GICC_SIZE   0x100ULL
+
+#define GUEST_RAM_BASE    0x80000000ULL
+
+#define GUEST_GNTTAB_BASE 0xb0000000ULL
+#define GUEST_GNTTAB_SIZE 0x00020000ULL
+
+/* Interrupts */
+#define GUEST_TIMER_VIRT_PPI    27
+#define GUEST_TIMER_PHYS_S_PPI  29
+#define GUEST_TIMER_PHYS_NS_PPI 30
+#define GUEST_EVTCHN_PPI        31
+
+/* PSCI functions */
+#define PSCI_cpu_suspend 0
+#define PSCI_cpu_off     1
+#define PSCI_cpu_on      2
+#define PSCI_migrate     3
+
 #endif
-#define PSR_IT_MASK     (0x0600fc00)  /* Thumb If-Then Mask */
-#define PSR_JAZELLE     (1<<24)       /* Jazelle Mode */
 
 #endif /*  __XEN_PUBLIC_ARCH_ARM_H__ */
 
-- 
1.7.10.4