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-rw-r--r--arch/c6x/platforms/emif.c87
1 files changed, 87 insertions, 0 deletions
diff --git a/arch/c6x/platforms/emif.c b/arch/c6x/platforms/emif.c
new file mode 100644
index 00000000000..8b564dec241
--- /dev/null
+++ b/arch/c6x/platforms/emif.c
@@ -0,0 +1,87 @@
+/*
+ * External Memory Interface
+ *
+ * Copyright (C) 2011 Texas Instruments Incorporated
+ * Author: Mark Salter <msalter@redhat.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/io.h>
+#include <asm/soc.h>
+#include <asm/dscr.h>
+
+#define NUM_EMIFA_CHIP_ENABLES 4
+
+struct emifa_regs {
+ u32 midr;
+ u32 stat;
+ u32 reserved1[6];
+ u32 bprio;
+ u32 reserved2[23];
+ u32 cecfg[NUM_EMIFA_CHIP_ENABLES];
+ u32 reserved3[4];
+ u32 awcc;
+ u32 reserved4[7];
+ u32 intraw;
+ u32 intmsk;
+ u32 intmskset;
+ u32 intmskclr;
+};
+
+static struct of_device_id emifa_match[] __initdata = {
+ { .compatible = "ti,c64x+emifa" },
+ {}
+};
+
+/*
+ * Parse device tree for existence of an EMIF (External Memory Interface)
+ * and initialize it if found.
+ */
+static int __init c6x_emifa_init(void)
+{
+ struct emifa_regs __iomem *regs;
+ struct device_node *node;
+ const __be32 *p;
+ u32 val;
+ int i, len, err;
+
+ node = of_find_matching_node(NULL, emifa_match);
+ if (!node)
+ return 0;
+
+ regs = of_iomap(node, 0);
+ if (!regs)
+ return 0;
+
+ /* look for a dscr-based enable for emifa pin buffers */
+ err = of_property_read_u32_array(node, "ti,dscr-dev-enable", &val, 1);
+ if (!err)
+ dscr_set_devstate(val, DSCR_DEVSTATE_ENABLED);
+
+ /* set up the chip enables */
+ p = of_get_property(node, "ti,emifa-ce-config", &len);
+ if (p) {
+ len /= sizeof(u32);
+ if (len > NUM_EMIFA_CHIP_ENABLES)
+ len = NUM_EMIFA_CHIP_ENABLES;
+ for (i = 0; i <= len; i++)
+ soc_writel(be32_to_cpup(&p[i]), &regs->cecfg[i]);
+ }
+
+ err = of_property_read_u32_array(node, "ti,emifa-burst-priority", &val, 1);
+ if (!err)
+ soc_writel(val, &regs->bprio);
+
+ err = of_property_read_u32_array(node, "ti,emifa-async-wait-control", &val, 1);
+ if (!err)
+ soc_writel(val, &regs->awcc);
+
+ iounmap(regs);
+ of_node_put(node);
+ return 0;
+}
+pure_initcall(c6x_emifa_init);