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Diffstat (limited to 'arch/powerpc/platforms/wsp/scom_wsp.c')
-rw-r--r--arch/powerpc/platforms/wsp/scom_wsp.c77
1 files changed, 77 insertions, 0 deletions
diff --git a/arch/powerpc/platforms/wsp/scom_wsp.c b/arch/powerpc/platforms/wsp/scom_wsp.c
new file mode 100644
index 00000000000..4052e2259f3
--- /dev/null
+++ b/arch/powerpc/platforms/wsp/scom_wsp.c
@@ -0,0 +1,77 @@
+/*
+ * SCOM backend for WSP
+ *
+ * Copyright 2010 Benjamin Herrenschmidt, IBM Corp.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ */
+
+#include <linux/cpumask.h>
+#include <linux/io.h>
+#include <linux/of.h>
+#include <linux/spinlock.h>
+#include <linux/types.h>
+
+#include <asm/cputhreads.h>
+#include <asm/reg_a2.h>
+#include <asm/scom.h>
+#include <asm/udbg.h>
+
+#include "wsp.h"
+
+
+static scom_map_t wsp_scom_map(struct device_node *dev, u64 reg, u64 count)
+{
+ struct resource r;
+ u64 xscom_addr;
+
+ if (!of_get_property(dev, "scom-controller", NULL)) {
+ pr_err("%s: device %s is not a SCOM controller\n",
+ __func__, dev->full_name);
+ return SCOM_MAP_INVALID;
+ }
+
+ if (of_address_to_resource(dev, 0, &r)) {
+ pr_debug("Failed to find SCOM controller address\n");
+ return 0;
+ }
+
+ /* Transform the SCOM address into an XSCOM offset */
+ xscom_addr = ((reg & 0x7f000000) >> 1) | ((reg & 0xfffff) << 3);
+
+ return (scom_map_t)ioremap(r.start + xscom_addr, count << 3);
+}
+
+static void wsp_scom_unmap(scom_map_t map)
+{
+ iounmap((void *)map);
+}
+
+static u64 wsp_scom_read(scom_map_t map, u32 reg)
+{
+ u64 __iomem *addr = (u64 __iomem *)map;
+
+ return in_be64(addr + reg);
+}
+
+static void wsp_scom_write(scom_map_t map, u32 reg, u64 value)
+{
+ u64 __iomem *addr = (u64 __iomem *)map;
+
+ return out_be64(addr + reg, value);
+}
+
+static const struct scom_controller wsp_scom_controller = {
+ .map = wsp_scom_map,
+ .unmap = wsp_scom_unmap,
+ .read = wsp_scom_read,
+ .write = wsp_scom_write
+};
+
+void scom_init_wsp(void)
+{
+ scom_init(&wsp_scom_controller);
+}