1 files changed, 84 insertions, 0 deletions
diff --git a/arch/c6x/platforms/emif.c b/arch/c6x/platforms/emif.c
new file mode 100644
index 000000000..6142ecc2c
--- /dev/null
+++ b/arch/c6x/platforms/emif.c
@@ -0,0 +1,84 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ *  External Memory Interface
+ *
+ *  Copyright (C) 2011 Texas Instruments Incorporated
+ *  Author: Mark Salter <msalter@redhat.com>
+ */
+#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);