[RFC PATCH v1 02/10] xen/arm: register mmio handler at runtime

[vijay.kilari@gmail.com]

From: Vijaya Kumar K <Vijaya.Kumar@caviumnetworks.com>

mmio handlers are registers at compile time
for drivers like vuart and vgic.
Make mmio handler registered at runtime by
creating linked list of mmio handlers

Signed-off-by: Vijaya Kumar K <Vijaya.Kumar@caviumnetworks.com>
---
 xen/arch/arm/io.c    |   32 +++++++++++++++++---------
 xen/arch/arm/io.h    |   16 +++++--------
 xen/arch/arm/vgic.c  |   61 ++++++++++++++++++++++++++------------------------
 xen/arch/arm/vuart.c |   39 ++++++++++++++++----------------
 4 files changed, 79 insertions(+), 69 deletions(-)

diff --git a/xen/arch/arm/io.c b/xen/arch/arm/io.c
index a6db00b..d140b29 100644
--- a/xen/arch/arm/io.c
+++ b/xen/arch/arm/io.c
@@ -17,31 +17,41 @@
  */
 
 #include <xen/config.h>
+#include <xen/init.h>
+#include <xen/kernel.h>
 #include <xen/lib.h>
+#include <xen/spinlock.h>
 #include <asm/current.h>
 
 #include "io.h"
 
-static const struct mmio_handler *const mmio_handlers[] =
-{
-    &vgic_distr_mmio_handler,
-    &vuart_mmio_handler,
-};
-#define MMIO_HANDLER_NR ARRAY_SIZE(mmio_handlers)
+LIST_HEAD(handle_head);
+static DEFINE_SPINLOCK(handler_lock);
 
 int handle_mmio(mmio_info_t *info)
 {
     struct vcpu *v = current;
-    int i;
+    struct list_head *pos;
+    struct mmio_handler *mmio_handle;
 
-    for ( i = 0; i < MMIO_HANDLER_NR; i++ )
-        if ( mmio_handlers[i]->check_handler(v, info->gpa) )
+    list_for_each(pos, &handle_head) {
+        mmio_handle = list_entry(pos, struct mmio_handler, handle_list);
+        if ( mmio_handle->check_handler(v, info->gpa) )
             return info->dabt.write ?
-                mmio_handlers[i]->write_handler(v, info) :
-                mmio_handlers[i]->read_handler(v, info);
+                mmio_handle->write_handler(v, info) :
+                mmio_handle->read_handler(v, info);
+    }
 
     return 0;
 }
+
+void register_mmio_handler(struct mmio_handler * handle)
+{
+    spin_lock(&handler_lock);
+    list_add(&handle->handle_list, &handle_head);
+    spin_unlock(&handler_lock);
+}
+
 /*
  * Local variables:
  * mode: C
diff --git a/xen/arch/arm/io.h b/xen/arch/arm/io.h
index 8d252c0..99cd7c3 100644
--- a/xen/arch/arm/io.h
+++ b/xen/arch/arm/io.h
@@ -22,6 +22,7 @@
 #include <xen/lib.h>
 #include <asm/processor.h>
 #include <asm/regs.h>
+#include <xen/list.h>
 
 typedef struct
 {
@@ -30,20 +31,15 @@ typedef struct
     paddr_t gpa;
 } mmio_info_t;
 
-typedef int (*mmio_read_t)(struct vcpu *v, mmio_info_t *info);
-typedef int (*mmio_write_t)(struct vcpu *v, mmio_info_t *info);
-typedef int (*mmio_check_t)(struct vcpu *v, paddr_t addr);
-
 struct mmio_handler {
-    mmio_check_t check_handler;
-    mmio_read_t read_handler;
-    mmio_write_t write_handler;
+    int (*read_handler)(struct vcpu *v, mmio_info_t *info);
+    int (*write_handler)(struct vcpu *v, mmio_info_t *info);
+    int (*check_handler)(struct vcpu *v, paddr_t addr);
+    struct list_head handle_list;
 };
 
-extern const struct mmio_handler vgic_distr_mmio_handler;
-extern const struct mmio_handler vuart_mmio_handler;
-
 extern int handle_mmio(mmio_info_t *info);
+void register_mmio_handler(struct mmio_handler * handle);
 
 #endif
 
diff --git a/xen/arch/arm/vgic.c b/xen/arch/arm/vgic.c
index 553411d..d2a13fb 100644
--- a/xen/arch/arm/vgic.c
+++ b/xen/arch/arm/vgic.c
@@ -73,34 +73,6 @@ static struct vgic_irq_rank *vgic_irq_rank(struct vcpu *v, int b, int n)
         return NULL;
 }
 
-int domain_vgic_init(struct domain *d)
-{
-    int i;
-
-    d->arch.vgic.ctlr = 0;
-
-    /* Currently nr_lines in vgic and gic doesn't have the same meanings
-     * Here nr_lines = number of SPIs
-     */
-    if ( d->domain_id == 0 )
-        d->arch.vgic.nr_lines = gic_number_lines() - 32;
-    else
-        d->arch.vgic.nr_lines = 0; /* We don't need SPIs for the guest */
-
-    d->arch.vgic.shared_irqs =
-        xzalloc_array(struct vgic_irq_rank, DOMAIN_NR_RANKS(d));
-    d->arch.vgic.pending_irqs =
-        xzalloc_array(struct pending_irq, d->arch.vgic.nr_lines);
-    for (i=0; i<d->arch.vgic.nr_lines; i++)
-    {
-        INIT_LIST_HEAD(&d->arch.vgic.pending_irqs[i].inflight);
-        INIT_LIST_HEAD(&d->arch.vgic.pending_irqs[i].lr_queue);
-    }
-    for (i=0; i<DOMAIN_NR_RANKS(d); i++)
-        spin_lock_init(&d->arch.vgic.shared_irqs[i].lock);
-    return 0;
-}
-
 void domain_vgic_free(struct domain *d)
 {
     xfree(d->arch.vgic.shared_irqs);
@@ -655,12 +627,43 @@ static int vgic_distr_mmio_check(struct vcpu *v, paddr_t addr)
     return (addr >= (d->arch.vgic.dbase)) && (addr < (d->arch.vgic.dbase + PAGE_SIZE));
 }
 
-const struct mmio_handler vgic_distr_mmio_handler = {
+static struct mmio_handler vgic_distr_mmio_handler = {
     .check_handler = vgic_distr_mmio_check,
     .read_handler  = vgic_distr_mmio_read,
     .write_handler = vgic_distr_mmio_write,
 };
 
+int domain_vgic_init(struct domain *d)
+{
+    int i;
+
+    d->arch.vgic.ctlr = 0;
+
+    /* Currently nr_lines in vgic and gic doesn't have the same meanings
+     * Here nr_lines = number of SPIs
+     */
+    if ( d->domain_id == 0 )
+        d->arch.vgic.nr_lines = gic_number_lines() - 32;
+    else
+        d->arch.vgic.nr_lines = 0; /* We don't need SPIs for the guest */
+
+    d->arch.vgic.shared_irqs =
+        xzalloc_array(struct vgic_irq_rank, DOMAIN_NR_RANKS(d));
+    d->arch.vgic.pending_irqs =
+        xzalloc_array(struct pending_irq, d->arch.vgic.nr_lines);
+    for (i=0; i<d->arch.vgic.nr_lines; i++)
+    {
+        INIT_LIST_HEAD(&d->arch.vgic.pending_irqs[i].inflight);
+        INIT_LIST_HEAD(&d->arch.vgic.pending_irqs[i].lr_queue);
+    }
+    for (i=0; i<DOMAIN_NR_RANKS(d); i++)
+        spin_lock_init(&d->arch.vgic.shared_irqs[i].lock);
+
+    register_mmio_handler(&vgic_distr_mmio_handler);
+    return 0;
+}
+
+
 struct pending_irq *irq_to_pending(struct vcpu *v, unsigned int irq)
 {
     struct pending_irq *n;
diff --git a/xen/arch/arm/vuart.c b/xen/arch/arm/vuart.c
index b9d3ced..c237d71 100644
--- a/xen/arch/arm/vuart.c
+++ b/xen/arch/arm/vuart.c
@@ -44,24 +44,6 @@
 
 #define domain_has_vuart(d) ((d)->arch.vuart.info != NULL)
 
-int domain_vuart_init(struct domain *d)
-{
-    ASSERT( !d->domain_id );
-
-    d->arch.vuart.info = serial_vuart_info(SERHND_DTUART);
-    if ( !d->arch.vuart.info )
-        return 0;
-
-    spin_lock_init(&d->arch.vuart.lock);
-    d->arch.vuart.idx = 0;
-
-    d->arch.vuart.buf = xzalloc_array(char, VUART_BUF_SIZE);
-    if ( !d->arch.vuart.buf )
-        return -ENOMEM;
-
-    return 0;
-}
-
 void domain_vuart_free(struct domain *d)
 {
     if ( !domain_has_vuart(d) )
@@ -133,12 +115,31 @@ static int vuart_mmio_write(struct vcpu *v, mmio_info_t *info)
     return 1;
 }
 
-const struct mmio_handler vuart_mmio_handler = {
+static struct mmio_handler vuart_mmio_handler = {
     .check_handler = vuart_mmio_check,
     .read_handler  = vuart_mmio_read,
     .write_handler = vuart_mmio_write,
 };
 
+int domain_vuart_init(struct domain *d)
+{
+    ASSERT( !d->domain_id );
+
+    d->arch.vuart.info = serial_vuart_info(SERHND_DTUART);
+    if ( !d->arch.vuart.info )
+        return 0;
+
+    spin_lock_init(&d->arch.vuart.lock);
+    d->arch.vuart.idx = 0;
+
+    d->arch.vuart.buf = xzalloc_array(char, VUART_BUF_SIZE);
+    if ( !d->arch.vuart.buf )
+        return -ENOMEM;
+
+    register_mmio_handler(&vuart_mmio_handler);
+    return 0;
+}
+
 /*
  * Local variables:
  * mode: C
-- 
1.7.9.5