1 files changed, 116 insertions, 0 deletions
diff --git a/arch/arm/plat-omap/sram.c b/arch/arm/plat-omap/sram.c
new file mode 100644
index 0000000..7719a40
--- /dev/null
+++ b/arch/arm/plat-omap/sram.c
@@ -0,0 +1,116 @@
+/*
+ * linux/arch/arm/plat-omap/sram.c
+ *
+ * OMAP SRAM detection and management
+ *
+ * Copyright (C) 2005 Nokia Corporation
+ * Written by Tony Lindgren <tony@atomide.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/config.h>
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/init.h>
+
+#include <asm/mach/map.h>
+#include <asm/io.h>
+#include <asm/cacheflush.h>
+
+#include "sram.h"
+
+#define OMAP1_SRAM_BASE		0xd0000000
+#define OMAP1_SRAM_START	0x20000000
+#define SRAM_BOOTLOADER_SZ	0x80
+
+static unsigned long omap_sram_base;
+static unsigned long omap_sram_size;
+static unsigned long omap_sram_ceil;
+
+/*
+ * The amount of SRAM depends on the core type:
+ * 730 = 200K, 1510 = 512K, 5912 = 256K, 1610 = 16K, 1710 = 16K
+ * Note that we cannot try to test for SRAM here because writes
+ * to secure SRAM will hang the system. Also the SRAM is not
+ * yet mapped at this point.
+ */
+void __init omap_detect_sram(void)
+{
+	omap_sram_base = OMAP1_SRAM_BASE;
+
+	if (cpu_is_omap730())
+		omap_sram_size = 0x32000;
+	else if (cpu_is_omap1510())
+		omap_sram_size = 0x80000;
+	else if (cpu_is_omap1610() || cpu_is_omap1621() || cpu_is_omap1710())
+		omap_sram_size = 0x4000;
+	else if (cpu_is_omap1611())
+		omap_sram_size = 0x3e800;
+	else {
+		printk(KERN_ERR "Could not detect SRAM size\n");
+		omap_sram_size = 0x4000;
+	}
+
+	printk(KERN_INFO "SRAM size: 0x%lx\n", omap_sram_size);
+	omap_sram_ceil = omap_sram_base + omap_sram_size;
+}
+
+static struct map_desc omap_sram_io_desc[] __initdata = {
+	{ OMAP1_SRAM_BASE, OMAP1_SRAM_START, 0, MT_DEVICE }
+};
+
+/*
+ * In order to use last 2kB of SRAM on 1611b, we must round the size
+ * up to multiple of PAGE_SIZE. We cannot use ioremap for SRAM, as
+ * clock init needs SRAM early.
+ */
+void __init omap_map_sram(void)
+{
+	if (omap_sram_size == 0)
+		return;
+
+	omap_sram_io_desc[0].length = (omap_sram_size + PAGE_SIZE-1)/PAGE_SIZE;
+	omap_sram_io_desc[0].length *= PAGE_SIZE;
+	iotable_init(omap_sram_io_desc, ARRAY_SIZE(omap_sram_io_desc));
+
+	/*
+	 * Looks like we need to preserve some bootloader code at the
+	 * beginning of SRAM for jumping to flash for reboot to work...
+	 */
+	memset((void *)omap_sram_base + SRAM_BOOTLOADER_SZ, 0,
+	       omap_sram_size - SRAM_BOOTLOADER_SZ);
+}
+
+static void (*_omap_sram_reprogram_clock)(u32 dpllctl, u32 ckctl) = NULL;
+
+void omap_sram_reprogram_clock(u32 dpllctl, u32 ckctl)
+{
+	if (_omap_sram_reprogram_clock == NULL)
+		panic("Cannot use SRAM");
+
+	return _omap_sram_reprogram_clock(dpllctl, ckctl);
+}
+
+void * omap_sram_push(void * start, unsigned long size)
+{
+	if (size > (omap_sram_ceil - (omap_sram_base + SRAM_BOOTLOADER_SZ))) {
+		printk(KERN_ERR "Not enough space in SRAM\n");
+		return NULL;
+	}
+	omap_sram_ceil -= size;
+	omap_sram_ceil &= ~0x3;
+	memcpy((void *)omap_sram_ceil, start, size);
+
+	return (void *)omap_sram_ceil;
+}
+
+void __init omap_sram_init(void)
+{
+	omap_detect_sram();
+	omap_map_sram();
+	_omap_sram_reprogram_clock = omap_sram_push(sram_reprogram_clock,
+						    sram_reprogram_clock_sz);
+}