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>

1 files changed, 146 insertions, 0 deletions

diff --git a/kernel/arch/cris/arch-v10/lib/dram_init.S b/kernel/arch/cris/arch-v10/lib/dram_init.S
new file mode 100644
index 000000000..e541d3d8f
--- /dev/null
+++ b/kernel/arch/cris/arch-v10/lib/dram_init.S
@@ -0,0 +1,146 @@
+/*
+ * DRAM/SDRAM initialization - alter with care
+ * This file is intended to be included from other assembler files
+ *
+ * Note: This file may not modify r9 because r9 is used to carry
+ *       information from the decompresser to the kernel
+ *
+ * Copyright (C) 2000-2012 Axis Communications AB
+ *
+ */
+
+/* Just to be certain the config file is included, we include it here
+ * explicitly instead of depending on it being included in the file that
+ * uses this code.
+ */
+
+
+	;; WARNING! The registers r8 and r9 are used as parameters carrying
+	;; information from the decompressor (if the kernel was compressed).
+	;; They should not be used in the code below.
+
+	move.d   CONFIG_ETRAX_DEF_R_WAITSTATES, $r0
+	move.d   $r0, [R_WAITSTATES]
+
+	move.d   CONFIG_ETRAX_DEF_R_BUS_CONFIG, $r0
+	move.d   $r0, [R_BUS_CONFIG]
+
+#ifndef CONFIG_ETRAX_SDRAM
+	move.d   CONFIG_ETRAX_DEF_R_DRAM_CONFIG, $r0
+	move.d   $r0, [R_DRAM_CONFIG]
+
+	move.d   CONFIG_ETRAX_DEF_R_DRAM_TIMING, $r0
+	move.d   $r0, [R_DRAM_TIMING]
+#else
+	;; Samsung SDRAMs seem to require to be initialized twice to work properly.
+	moveq    2, $r6	
+_sdram_init:
+
+	; Refer to ETRAX 100LX Designers Reference for a description of SDRAM initialization
+
+	; Bank configuration
+	move.d   CONFIG_ETRAX_DEF_R_SDRAM_CONFIG, $r0
+	move.d   $r0, [R_SDRAM_CONFIG]
+
+	; Calculate value of mrs_data
+	; CAS latency = 2 && bus_width = 32 => 0x40
+	; CAS latency = 3 && bus_width = 32 => 0x60
+	; CAS latency = 2 && bus_width = 16 => 0x20
+	; CAS latency = 3 && bus_width = 16 => 0x30
+
+	; Check if value is already supplied in kernel config
+	move.d   CONFIG_ETRAX_DEF_R_SDRAM_TIMING, $r2
+	and.d    0x00ff0000, $r2
+	bne	 _set_timing
+	lsrq     16, $r2
+
+	move.d   0x40, $r2       ; Assume 32 bits and CAS latency = 2
+	move.d   CONFIG_ETRAX_DEF_R_SDRAM_TIMING, $r1
+	move.d   $r1, $r3
+	and.d    0x03, $r1       ; Get CAS latency
+	and.d    0x1000, $r3     ; 50 or 100 MHz?
+	beq      _speed_50
+	nop
+_speed_100:
+	cmp.d    0x00, $r1	; CAS latency = 2?
+	beq      _bw_check
+	nop
+	or.d     0x20, $r2	; CAS latency = 3
+	ba       _bw_check
+	nop
+_speed_50:
+	cmp.d    0x01, $r1	; CAS latency = 2?
+	beq      _bw_check
+	nop
+	or.d     0x20, $r2       ; CAS latency = 3
+_bw_check:
+	move.d   CONFIG_ETRAX_DEF_R_SDRAM_CONFIG, $r1
+	and.d    0x800000, $r1	; DRAM width is bit 23
+	bne      _set_timing
+	nop
+	lsrq     1, $r2		;  16 bits. Shift down value.
+
+	; Set timing parameters. Starts master clock
+_set_timing:
+	move.d   CONFIG_ETRAX_DEF_R_SDRAM_TIMING, $r1
+	and.d    0x8000f9ff, $r1 ; Make sure mrs data and command is 0
+	or.d     0x80000000, $r1	; Make sure sdram enable bit is set
+	move.d   $r1, $r5
+	or.d     0x0000c000, $r1 ; ref = disable
+	lslq     16, $r2		; mrs data starts at bit 16
+	or.d     $r2, $r1
+	move.d   $r1, [R_SDRAM_TIMING]
+
+	; Wait 200us
+	move.d   10000, $r2
+1:	bne      1b
+	subq     1, $r2
+
+	; Issue initialization command sequence
+	move.d   _sdram_commands_start, $r2
+	and.d    0x000fffff, $r2 ; Make sure commands are read from flash
+	move.d   _sdram_commands_end,  $r3
+	and.d    0x000fffff, $r3
+1:	clear.d  $r4
+	move.b   [$r2+], $r4
+	lslq     9, $r4	; Command starts at bit 9
+	or.d     $r1, $r4
+	move.d   $r4, [R_SDRAM_TIMING]
+	nop		; Wait five nop cycles between each command
+	nop
+	nop
+	nop
+	nop
+	cmp.d    $r2, $r3
+	bne      1b
+	nop
+	move.d   $r5, [R_SDRAM_TIMING]
+	subq     1, $r6
+	bne      _sdram_init
+	nop
+	ba       _sdram_commands_end
+	nop
+
+_sdram_commands_start:
+	.byte   3	; Precharge
+	.byte   0       ; nop
+	.byte   2	; refresh
+	.byte   0	; nop
+	.byte   2	; refresh
+	.byte   0	; nop
+	.byte   2	; refresh
+	.byte   0	; nop
+	.byte   2	; refresh
+	.byte   0	; nop
+	.byte   2	; refresh
+	.byte   0	; nop
+	.byte   2	; refresh
+	.byte   0	; nop
+	.byte   2	; refresh
+	.byte   0	; nop
+	.byte   2	; refresh
+	.byte   0	; nop
+	.byte   1	; mrs
+	.byte   0	; nop
+_sdram_commands_end:
+#endif