From 0b1d127081896411bf91693acb1932345e0e627a Mon Sep 17 00:00:00 2001 From: Julien Grall Date: Mon, 6 Jan 2014 16:36:18 +0000 Subject: [PATCH] xen/dts: Don't translate invalid address ePAR specifies that if the property "ranges" doesn't exist in a bus node: "it is assumed that no mapping exists between children of node and the parent address space". Modify dt_number_of_address to check if the list of ranges are valid. Return 0 (ie there is zero range) if the list is not valid. This patch has been tested on the Arndale where the bug can occur with the '/hdmi' node. Reported-by: Signed-off-by: Julien Grall Acked-by: Ian Campbell --- xen/common/device_tree.c | 29 ++++++++++++++++++++++++++--- 1 file changed, 26 insertions(+), 3 deletions(-) diff --git a/xen/common/device_tree.c b/xen/common/device_tree.c index a29d9f2eb7..55716a8626 100644 --- a/xen/common/device_tree.c +++ b/xen/common/device_tree.c @@ -93,7 +93,7 @@ struct dt_bus { const char *name; const char *addresses; - int (*match)(const struct dt_device_node *parent); + bool_t (*match)(const struct dt_device_node *node); void (*count_cells)(const struct dt_device_node *child, int *addrc, int *sizec); u64 (*map)(__be32 *addr, const __be32 *range, int na, int ns, int pna); @@ -793,6 +793,18 @@ int dt_n_size_cells(const struct dt_device_node *np) /* * Default translator (generic bus) */ +static bool_t dt_bus_default_match(const struct dt_device_node *node) +{ + /* Root node doesn't have "ranges" property */ + if ( node->parent == NULL ) + return 1; + + /* The default bus is only used when the "ranges" property exists. + * Otherwise we can't translate the address + */ + return (dt_get_property(node, "ranges", NULL) != NULL); +} + static void dt_bus_default_count_cells(const struct dt_device_node *dev, int *addrc, int *sizec) { @@ -856,7 +868,7 @@ static const struct dt_bus dt_busses[] = { .name = "default", .addresses = "reg", - .match = NULL, + .match = dt_bus_default_match, .count_cells = dt_bus_default_count_cells, .map = dt_bus_default_map, .translate = dt_bus_default_translate, @@ -871,7 +883,6 @@ static const struct dt_bus *dt_match_bus(const struct dt_device_node *np) for ( i = 0; i < ARRAY_SIZE(dt_busses); i++ ) if ( !dt_busses[i].match || dt_busses[i].match(np) ) return &dt_busses[i]; - BUG(); return NULL; } @@ -890,7 +901,10 @@ static const __be32 *dt_get_address(const struct dt_device_node *dev, parent = dt_get_parent(dev); if ( parent == NULL ) return NULL; + bus = dt_match_bus(parent); + if ( !bus ) + return NULL; bus->count_cells(dev, &na, &ns); if ( !DT_CHECK_ADDR_COUNT(na) ) @@ -994,6 +1008,8 @@ static u64 __dt_translate_address(const struct dt_device_node *dev, if ( parent == NULL ) goto bail; bus = dt_match_bus(parent); + if ( !bus ) + goto bail; /* Count address cells & copy address locally */ bus->count_cells(dev, &na, &ns); @@ -1026,6 +1042,11 @@ static u64 __dt_translate_address(const struct dt_device_node *dev, /* Get new parent bus and counts */ pbus = dt_match_bus(parent); + if ( pbus == NULL ) + { + dt_printk("DT: %s is not a valid bus\n", parent->full_name); + break; + } pbus->count_cells(dev, &pna, &pns); if ( !DT_CHECK_COUNTS(pna, pns) ) { @@ -1164,6 +1185,8 @@ unsigned int dt_number_of_address(const struct dt_device_node *dev) return 0; bus = dt_match_bus(parent); + if ( !bus ) + return 0; bus->count_cells(dev, &na, &ns); if ( !DT_CHECK_COUNTS(na, ns) ) -- 2.30.2