[PATCH v2 04/15] xen: arm: add a quirk to handle platforms with unusual GIC layout

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

Use this quirk on the xgene platform.

This should ideally be fixed by an extension to the device tree bindings as
described in http://www.spinics.net/lists/devicetree/msg10473.html especially
http://www.spinics.net/lists/devicetree/msg10478.html. However for the time
being a platform specific quirk will do.

Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
---
v2: This replaces "xen: arm: GICC_DIR register at offset 0x10000 instead of 0x1000"
---
 xen/arch/arm/gic.c                   |    6 +++++-
 xen/arch/arm/platforms/xgene-storm.c |    2 +-
 xen/include/asm-arm/platform.h       |    5 +++++
 3 files changed, 11 insertions(+), 2 deletions(-)

diff --git a/xen/arch/arm/gic.c b/xen/arch/arm/gic.c
index ab49106..9711f5d 100644
--- a/xen/arch/arm/gic.c
+++ b/xen/arch/arm/gic.c
@@ -30,6 +30,7 @@
 #include <xen/device_tree.h>
 #include <asm/p2m.h>
 #include <asm/domain.h>
+#include <asm/platform.h>
 
 #include <asm/gic.h>
 
@@ -444,7 +445,10 @@ void __init gic_init(void)
     BUILD_BUG_ON(FIXMAP_ADDR(FIXMAP_GICC1) !=
                  FIXMAP_ADDR(FIXMAP_GICC2)-PAGE_SIZE);
     set_fixmap(FIXMAP_GICC1, gic.cbase >> PAGE_SHIFT, DEV_SHARED);
-    set_fixmap(FIXMAP_GICC2, (gic.cbase >> PAGE_SHIFT) + 1, DEV_SHARED);
+    if ( platform_has_quirk(PLATFORM_QUIRK_GIC_64K_STRIDE) )
+        set_fixmap(FIXMAP_GICC2, (gic.cbase >> PAGE_SHIFT) + 0x10, DEV_SHARED);
+    else
+        set_fixmap(FIXMAP_GICC2, (gic.cbase >> PAGE_SHIFT) + 0x1, DEV_SHARED);
     set_fixmap(FIXMAP_GICH, gic.hbase >> PAGE_SHIFT, DEV_SHARED);
 
     /* Global settings: interrupt distributor */
diff --git a/xen/arch/arm/platforms/xgene-storm.c b/xen/arch/arm/platforms/xgene-storm.c
index 727ac2b..d185a4a 100644
--- a/xen/arch/arm/platforms/xgene-storm.c
+++ b/xen/arch/arm/platforms/xgene-storm.c
@@ -27,7 +27,7 @@
 
 static uint32_t xgene_storm_quirks(void)
 {
-    return PLATFORM_QUIRK_DOM0_MAPPING_11;
+    return PLATFORM_QUIRK_DOM0_MAPPING_11|PLATFORM_QUIRK_GIC_64K_STRIDE;
 }
 
 
diff --git a/xen/include/asm-arm/platform.h b/xen/include/asm-arm/platform.h
index c282b30..c9314e5 100644
--- a/xen/include/asm-arm/platform.h
+++ b/xen/include/asm-arm/platform.h
@@ -44,6 +44,11 @@ struct platform_desc {
  * Useful on platform where System MMU is not yet implemented
  */
 #define PLATFORM_QUIRK_DOM0_MAPPING_11 (1 << 0)
+/*
+ * Quirk for platforms where the 4K GIC register ranges are placed at
+ * 64K stride.
+ */
+#define PLATFORM_QUIRK_GIC_64K_STRIDE (1 << 1)
 
 void __init platform_init(void);
 int __init platform_init_time(void);
-- 
1.7.10.4