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authorEzequiel Garcia <ezequiel.garcia@free-electrons.com>2013-07-26 17:17:46 +0400
committerJason Cooper <jason@lakedaemon.net>2013-08-06 18:10:29 +0400
commitbb24cab39c7b6971db88d9a72d8d661b9ee887ea (patch)
tree19773ce6db923f2277acf6961f46aa4039c0b379 /drivers/bus
parent6839cfa82f99fd098ea486e7f9df78344c8e091f (diff)
downloadlinux-bb24cab39c7b6971db88d9a72d8d661b9ee887ea.tar.xz
bus: mvebu-mbus: Add static window allocation to the DT binding
This patch adds static window allocation to the device tree binding. Each first-child of the mbus-compatible node, with a suitable 'ranges' property, declaring an address translation, will trigger an address decoding window allocation. Signed-off-by: Ezequiel Garcia <ezequiel.garcia@free-electrons.com> Tested-by: Andrew Lunn <andrew@lunn.ch> Tested-by: Sebastian Hesselbarth <sebastian.hesselbarth@gmail.com> Signed-off-by: Jason Cooper <jason@lakedaemon.net>
Diffstat (limited to 'drivers/bus')
-rw-r--r--drivers/bus/mvebu-mbus.c127
1 files changed, 126 insertions, 1 deletions
diff --git a/drivers/bus/mvebu-mbus.c b/drivers/bus/mvebu-mbus.c
index 44a07c4ee4ea..78b8c0436f0b 100644
--- a/drivers/bus/mvebu-mbus.c
+++ b/drivers/bus/mvebu-mbus.c
@@ -902,6 +902,127 @@ int __init mvebu_mbus_init(const char *soc, phys_addr_t mbuswins_phys_base,
}
#ifdef CONFIG_OF
+/*
+ * The window IDs in the ranges DT property have the following format:
+ * - bits 28 to 31: MBus custom field
+ * - bits 24 to 27: window target ID
+ * - bits 16 to 23: window attribute ID
+ * - bits 0 to 15: unused
+ */
+#define CUSTOM(id) (((id) & 0xF0000000) >> 24)
+#define TARGET(id) (((id) & 0x0F000000) >> 24)
+#define ATTR(id) (((id) & 0x00FF0000) >> 16)
+
+static int __init mbus_dt_setup_win(struct mvebu_mbus_state *mbus,
+ u32 base, u32 size,
+ u8 target, u8 attr)
+{
+ const struct mvebu_mbus_mapping *map = mbus->soc->map;
+ const char *name;
+ int i;
+
+ /* Search for a suitable window in the existing mappings */
+ for (i = 0; map[i].name; i++)
+ if (map[i].target == target &&
+ map[i].attr == (attr & map[i].attrmask))
+ break;
+
+ name = map[i].name;
+ if (!name) {
+ pr_err("window 0x%x:0x%x is unknown, skipping\n",
+ target, attr);
+ return -EINVAL;
+ }
+
+ if (!mvebu_mbus_window_conflicts(mbus, base, size, target, attr)) {
+ pr_err("cannot add window '%s', conflicts with another window\n",
+ name);
+ return -EBUSY;
+ }
+
+ if (mvebu_mbus_alloc_window(mbus, base, size, MVEBU_MBUS_NO_REMAP,
+ target, attr)) {
+ pr_err("cannot add window '%s', too many windows\n",
+ name);
+ return -ENOMEM;
+ }
+ return 0;
+}
+
+static int __init
+mbus_parse_ranges(struct device_node *node,
+ int *addr_cells, int *c_addr_cells, int *c_size_cells,
+ int *cell_count, const __be32 **ranges_start,
+ const __be32 **ranges_end)
+{
+ const __be32 *prop;
+ int ranges_len, tuple_len;
+
+ /* Allow a node with no 'ranges' property */
+ *ranges_start = of_get_property(node, "ranges", &ranges_len);
+ if (*ranges_start == NULL) {
+ *addr_cells = *c_addr_cells = *c_size_cells = *cell_count = 0;
+ *ranges_start = *ranges_end = NULL;
+ return 0;
+ }
+ *ranges_end = *ranges_start + ranges_len / sizeof(__be32);
+
+ *addr_cells = of_n_addr_cells(node);
+
+ prop = of_get_property(node, "#address-cells", NULL);
+ *c_addr_cells = be32_to_cpup(prop);
+
+ prop = of_get_property(node, "#size-cells", NULL);
+ *c_size_cells = be32_to_cpup(prop);
+
+ *cell_count = *addr_cells + *c_addr_cells + *c_size_cells;
+ tuple_len = (*cell_count) * sizeof(__be32);
+
+ if (ranges_len % tuple_len) {
+ pr_warn("malformed ranges entry '%s'\n", node->name);
+ return -EINVAL;
+ }
+ return 0;
+}
+
+static int __init mbus_dt_setup(struct mvebu_mbus_state *mbus,
+ struct device_node *np)
+{
+ int addr_cells, c_addr_cells, c_size_cells;
+ int i, ret, cell_count;
+ const __be32 *r, *ranges_start, *ranges_end;
+
+ ret = mbus_parse_ranges(np, &addr_cells, &c_addr_cells,
+ &c_size_cells, &cell_count,
+ &ranges_start, &ranges_end);
+ if (ret < 0)
+ return ret;
+
+ for (i = 0, r = ranges_start; r < ranges_end; r += cell_count, i++) {
+ u32 windowid, base, size;
+ u8 target, attr;
+
+ /*
+ * An entry with a non-zero custom field do not
+ * correspond to a static window, so skip it.
+ */
+ windowid = of_read_number(r, 1);
+ if (CUSTOM(windowid))
+ continue;
+
+ target = TARGET(windowid);
+ attr = ATTR(windowid);
+
+ base = of_read_number(r + c_addr_cells, addr_cells);
+ size = of_read_number(r + c_addr_cells + addr_cells,
+ c_size_cells);
+ ret = mbus_dt_setup_win(mbus, base, size, target, attr);
+ if (ret < 0)
+ return ret;
+ }
+ return 0;
+}
+
int __init mvebu_mbus_dt_init(void)
{
struct resource mbuswins_res, sdramwins_res;
@@ -946,6 +1067,10 @@ int __init mvebu_mbus_dt_init(void)
resource_size(&mbuswins_res),
sdramwins_res.start,
resource_size(&sdramwins_res));
- return ret;
+ if (ret)
+ return ret;
+
+ /* Setup statically declared windows in the DT */
+ return mbus_dt_setup(&mbus_state, np);
}
#endif