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authorYunhong Jiang <yunhong.jiang@intel.com>2015-08-04 12:17:53 -0700
committerYunhong Jiang <yunhong.jiang@intel.com>2015-08-04 15:44:42 -0700
commit9ca8dbcc65cfc63d6f5ef3312a33184e1d726e00 (patch)
tree1c9cafbcd35f783a87880a10f85d1a060db1a563 /kernel/drivers/tty/hvc/hvc_bfin_jtag.c
parent98260f3884f4a202f9ca5eabed40b1354c489b29 (diff)
Add the rt linux 4.1.3-rt3 as base
Import the rt linux 4.1.3-rt3 as OPNFV kvm base. It's from git://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-rt-devel.git linux-4.1.y-rt and the base is: commit 0917f823c59692d751951bf5ea699a2d1e2f26a2 Author: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Date: Sat Jul 25 12:13:34 2015 +0200 Prepare v4.1.3-rt3 Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> We lose all the git history this way and it's not good. We should apply another opnfv project repo in future. Change-Id: I87543d81c9df70d99c5001fbdf646b202c19f423 Signed-off-by: Yunhong Jiang <yunhong.jiang@intel.com>
Diffstat (limited to 'kernel/drivers/tty/hvc/hvc_bfin_jtag.c')
-rw-r--r--kernel/drivers/tty/hvc/hvc_bfin_jtag.c105
1 files changed, 105 insertions, 0 deletions
diff --git a/kernel/drivers/tty/hvc/hvc_bfin_jtag.c b/kernel/drivers/tty/hvc/hvc_bfin_jtag.c
new file mode 100644
index 000000000..31d6cc6a7
--- /dev/null
+++ b/kernel/drivers/tty/hvc/hvc_bfin_jtag.c
@@ -0,0 +1,105 @@
+/*
+ * Console via Blackfin JTAG Communication
+ *
+ * Copyright 2008-2011 Analog Devices Inc.
+ *
+ * Enter bugs at http://blackfin.uclinux.org/
+ *
+ * Licensed under the GPL-2 or later.
+ */
+
+#include <linux/console.h>
+#include <linux/delay.h>
+#include <linux/err.h>
+#include <linux/init.h>
+#include <linux/moduleparam.h>
+#include <linux/types.h>
+
+#include "hvc_console.h"
+
+/* See the Debug/Emulation chapter in the HRM */
+#define EMUDOF 0x00000001 /* EMUDAT_OUT full & valid */
+#define EMUDIF 0x00000002 /* EMUDAT_IN full & valid */
+#define EMUDOOVF 0x00000004 /* EMUDAT_OUT overflow */
+#define EMUDIOVF 0x00000008 /* EMUDAT_IN overflow */
+
+/* Helper functions to glue the register API to simple C operations */
+static inline uint32_t bfin_write_emudat(uint32_t emudat)
+{
+ __asm__ __volatile__("emudat = %0;" : : "d"(emudat));
+ return emudat;
+}
+
+static inline uint32_t bfin_read_emudat(void)
+{
+ uint32_t emudat;
+ __asm__ __volatile__("%0 = emudat;" : "=d"(emudat));
+ return emudat;
+}
+
+/* Send data to the host */
+static int hvc_bfin_put_chars(uint32_t vt, const char *buf, int count)
+{
+ static uint32_t outbound_len;
+ uint32_t emudat;
+ int ret;
+
+ if (bfin_read_DBGSTAT() & EMUDOF)
+ return 0;
+
+ if (!outbound_len) {
+ outbound_len = count;
+ bfin_write_emudat(outbound_len);
+ return 0;
+ }
+
+ ret = min(outbound_len, (uint32_t)4);
+ memcpy(&emudat, buf, ret);
+ bfin_write_emudat(emudat);
+ outbound_len -= ret;
+
+ return ret;
+}
+
+/* Receive data from the host */
+static int hvc_bfin_get_chars(uint32_t vt, char *buf, int count)
+{
+ static uint32_t inbound_len;
+ uint32_t emudat;
+ int ret;
+
+ if (!(bfin_read_DBGSTAT() & EMUDIF))
+ return 0;
+ emudat = bfin_read_emudat();
+
+ if (!inbound_len) {
+ inbound_len = emudat;
+ return 0;
+ }
+
+ ret = min(inbound_len, (uint32_t)4);
+ memcpy(buf, &emudat, ret);
+ inbound_len -= ret;
+
+ return ret;
+}
+
+/* Glue the HVC layers to the Blackfin layers */
+static const struct hv_ops hvc_bfin_get_put_ops = {
+ .get_chars = hvc_bfin_get_chars,
+ .put_chars = hvc_bfin_put_chars,
+};
+
+static int __init hvc_bfin_console_init(void)
+{
+ hvc_instantiate(0, 0, &hvc_bfin_get_put_ops);
+ return 0;
+}
+console_initcall(hvc_bfin_console_init);
+
+static int __init hvc_bfin_init(void)
+{
+ hvc_alloc(0, 0, &hvc_bfin_get_put_ops, 128);
+ return 0;
+}
+device_initcall(hvc_bfin_init);