[PATCH 30/36] xen/arm: add coloring support to dom0less

[Marco Solieri <marco.solieri@xxxxxxxxxxxxxxx>]

From: Luca Miccio <lucmiccio@xxxxxxxxx>

Dom0less color assignment is performed via Device Tree with a new
attribute "colors". In this case the color assignment is represented by
a bitmask where it suffices to set all and only the bits having a
position equal to the chosen colors, leaving unset all the others.

Signed-off-by: Luca Miccio <lucmiccio@xxxxxxxxx>
Signed-off-by: Marco Solieri <marco.solieri@xxxxxxxxxxxxxxx>
---
 xen/arch/arm/domain_build.c | 30 ++++++++++++++++++++++++++++++
 1 file changed, 30 insertions(+)

diff --git a/xen/arch/arm/domain_build.c b/xen/arch/arm/domain_build.c
index 03a2573d67..c7ca45c0c4 100644
--- a/xen/arch/arm/domain_build.c
+++ b/xen/arch/arm/domain_build.c
@@ -27,6 +27,7 @@
 #include <asm/setup.h>
 #include <asm/cpufeature.h>
 #include <asm/domain_build.h>
+#include <asm/coloring.h>
 
 #include <xen/irq.h>
 #include <xen/grant_table.h>
@@ -3173,6 +3174,10 @@ void __init create_domUs(void)
 {
     struct dt_device_node *node;
     const struct dt_device_node *chosen = dt_find_node_by_path("/chosen");
+    u32 col_val;
+    const u32 *cells;
+    u32 len;
+    int cell, i, k;
 
     BUG_ON(chosen == NULL);
     dt_for_each_child_node(chosen, node)
@@ -3241,6 +3246,31 @@ void __init create_domUs(void)
                                          vpl011_virq - 32 + 1);
         }
 
+        d_cfg.arch.colors.max_colors = 0;
+        memset(&d_cfg.arch.colors.colors, 0x0, 
sizeof(d_cfg.arch.colors.colors));
+
+        cells = dt_get_property(node, "colors", &len);
+        if ( cells != NULL && len > 0 )
+        {
+            if ( !get_max_colors() )
+                panic("Coloring requested but no colors configuration 
found!\n");
+
+            if ( len > sizeof(d_cfg.arch.colors.colors) )
+                panic("Dom0less DomU color information is invalid\n");
+
+            for ( k = 0, cell = len/4 - 1; cell >= 0; cell--, k++ )
+            {
+                col_val = be32_to_cpup(&cells[cell]);
+                if ( col_val )
+                {
+                    /* Calculate number of bit set */
+                    for ( i = 0; i < 32; i++)
+                        if ( col_val & (1 << i) )
+                            d_cfg.arch.colors.max_colors++;
+                    d_cfg.arch.colors.colors[k] = col_val;
+                }
+            }
+        }
         /*
          * The variable max_init_domid is initialized with zero, so here it's
          * very important to use the pre-increment operator to call
-- 
2.30.2