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Diffstat (limited to 'arch/blackfin/mach-bf561/coreb.c')
-rw-r--r--arch/blackfin/mach-bf561/coreb.c77
1 files changed, 77 insertions, 0 deletions
diff --git a/arch/blackfin/mach-bf561/coreb.c b/arch/blackfin/mach-bf561/coreb.c
new file mode 100644
index 00000000..78ecb50b
--- /dev/null
+++ b/arch/blackfin/mach-bf561/coreb.c
@@ -0,0 +1,77 @@
+/* Load firmware into Core B on a BF561
+ *
+ * Copyright 2004-2009 Analog Devices Inc.
+ * Licensed under the GPL-2 or later.
+ */
+
+/* The Core B reset func requires code in the application that is loaded into
+ * Core B. In order to reset, the application needs to install an interrupt
+ * handler for Supplemental Interrupt 0, that sets RETI to 0xff600000 and
+ * writes bit 11 of SICB_SYSCR when bit 5 of SICA_SYSCR is 0. This causes Core
+ * B to stall when Supplemental Interrupt 0 is set, and will reset PC to
+ * 0xff600000 when COREB_SRAM_INIT is cleared.
+ */
+
+#include <linux/device.h>
+#include <linux/fs.h>
+#include <linux/kernel.h>
+#include <linux/miscdevice.h>
+#include <linux/module.h>
+
+#define CMD_COREB_START _IO('b', 0)
+#define CMD_COREB_STOP _IO('b', 1)
+#define CMD_COREB_RESET _IO('b', 2)
+
+static long
+coreb_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
+{
+ int ret = 0;
+
+ switch (cmd) {
+ case CMD_COREB_START:
+ bfin_write_SYSCR(bfin_read_SYSCR() & ~0x0020);
+ break;
+ case CMD_COREB_STOP:
+ bfin_write_SYSCR(bfin_read_SYSCR() | 0x0020);
+ bfin_write_SICB_SYSCR(bfin_read_SICB_SYSCR() | 0x0080);
+ break;
+ case CMD_COREB_RESET:
+ bfin_write_SICB_SYSCR(bfin_read_SICB_SYSCR() | 0x0080);
+ break;
+ default:
+ ret = -EINVAL;
+ break;
+ }
+
+ CSYNC();
+
+ return ret;
+}
+
+static const struct file_operations coreb_fops = {
+ .owner = THIS_MODULE,
+ .unlocked_ioctl = coreb_ioctl,
+ .llseek = noop_llseek,
+};
+
+static struct miscdevice coreb_dev = {
+ .minor = MISC_DYNAMIC_MINOR,
+ .name = "coreb",
+ .fops = &coreb_fops,
+};
+
+static int __init bf561_coreb_init(void)
+{
+ return misc_register(&coreb_dev);
+}
+module_init(bf561_coreb_init);
+
+static void __exit bf561_coreb_exit(void)
+{
+ misc_deregister(&coreb_dev);
+}
+module_exit(bf561_coreb_exit);
+
+MODULE_AUTHOR("Bas Vermeulen <bvermeul@blackstar.xs4all.nl>");
+MODULE_DESCRIPTION("BF561 Core B Support");
+MODULE_LICENSE("GPL");