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Diffstat (limited to 'arch/cris/arch-v10/lib/dram_init.S')
-rw-r--r--arch/cris/arch-v10/lib/dram_init.S40
1 files changed, 18 insertions, 22 deletions
diff --git a/arch/cris/arch-v10/lib/dram_init.S b/arch/cris/arch-v10/lib/dram_init.S
index b9190ff7d0a4..e541d3d8f922 100644
--- a/arch/cris/arch-v10/lib/dram_init.S
+++ b/arch/cris/arch-v10/lib/dram_init.S
@@ -5,9 +5,7 @@
* Note: This file may not modify r9 because r9 is used to carry
* information from the decompresser to the kernel
*
- * Copyright (C) 2000, 2001 Axis Communications AB
- *
- * Authors: Mikael Starvik (starvik@axis.com)
+ * Copyright (C) 2000-2012 Axis Communications AB
*
*/
@@ -18,16 +16,15 @@
;; WARNING! The registers r8 and r9 are used as parameters carrying
- ;; information from the decompressor (if the kernel was compressed).
+ ;; information from the decompressor (if the kernel was compressed).
;; They should not be used in the code below.
-#ifndef CONFIG_SVINTO_SIM
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]
@@ -38,14 +35,14 @@
;; 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
+ ; 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
@@ -56,22 +53,22 @@ _sdram_init:
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 0x03, $r1 ; Get CAS latency
and.d 0x1000, $r3 ; 50 or 100 MHz?
beq _speed_50
nop
-_speed_100:
+_speed_100:
cmp.d 0x00, $r1 ; CAS latency = 2?
beq _bw_check
nop
- or.d 0x20, $r2 ; CAS latency = 3
+ or.d 0x20, $r2 ; CAS latency = 3
ba _bw_check
nop
-_speed_50:
+_speed_50:
cmp.d 0x01, $r1 ; CAS latency = 2?
beq _bw_check
nop
@@ -86,19 +83,19 @@ _bw_check:
; 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
+ 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]
-
+ 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
@@ -144,7 +141,6 @@ _sdram_commands_start:
.byte 2 ; refresh
.byte 0 ; nop
.byte 1 ; mrs
- .byte 0 ; nop
-_sdram_commands_end:
-#endif
+ .byte 0 ; nop
+_sdram_commands_end:
#endif