2 * Rescue code, made to reside at the beginning of the
3 * flash-memory. when it starts, it checks a partition
4 * table at the first sector after the rescue sector.
5 * the partition table was generated by the product builder
6 * script and contains offsets, lengths, types and checksums
7 * for each partition that this code should check.
9 * If any of the checksums fail, we assume the flash is so
10 * corrupt that we cant use it to boot into the ftp flash
11 * loader, and instead we initialize the serial port to
12 * receive a flash-loader and new flash image. we dont include
13 * any flash code here, but just accept a certain amount of
14 * bytes from the serial port and jump into it. the downloaded
15 * code is put in the cache.
17 * The partitiontable is designed so that it is transparent to
18 * code execution - it has a relative branch opcode in the
19 * beginning that jumps over it. each entry contains extra
20 * data so we can add stuff later.
22 * Partition table format:
26 * 2 bytes [opcode 'nop']
27 * 2 bytes [opcode 'di']
28 * 4 bytes [opcode 'ba <offset>', 8-bit or 16-bit version]
29 * 2 bytes [opcode 'nop', delay slot]
31 * Table validation (at +10):
33 * 2 bytes [magic/version word for partitiontable - 0xef, 0xbe]
34 * 2 bytes [length of all entries plus the end marker]
35 * 4 bytes [checksum for the partitiontable itself]
37 * Entries, each with the following format, last has offset -1:
39 * 4 bytes [offset in bytes, from start of flash]
40 * 4 bytes [length in bytes of partition]
41 * 4 bytes [checksum, simple longword sum]
42 * 2 bytes [partition type]
43 * 2 bytes [flags, only bit 0 used, ro/rw = 1/0]
44 * 16 bytes [reserved for future use]
50 * 10 bytes [0, padding]
52 * Bit 0 in flags signifies RW or RO. The rescue code only bothers
53 * to check the checksum for RO partitions, since the others will
54 * change their data without updating the checksums. A 1 in bit 0
55 * means RO, 0 means RW. That way, it is possible to set a partition
56 * in RO mode initially, and later mark it as RW, since you can always
57 * write 0's to the flash.
59 * During the wait for serial input, the status LED will flash so the
60 * user knows something went wrong.
62 * Copyright (C) 1999-2007 Axis Communications AB
65 #ifdef CONFIG_ETRAX_AXISFLASHMAP
67 #define ASSEMBLER_MACROS_ONLY
68 #include <asm/arch/sv_addr_ag.h>
70 ;; The partitiontable is looked for at the first sector after the boot
71 ;; sector. Sector size is 65536 bytes in all flashes we use.
73 #define PTABLE_START CONFIG_ETRAX_PTABLE_SECTOR
74 #define PTABLE_MAGIC 0xbeef
76 ;; The normal Etrax100 on-chip boot ROM does serial boot at 0x380000f0.
77 ;; That is not where we put our downloaded serial boot-code. The length is
78 ;; enough for downloading code that loads the rest of itself (after
79 ;; having setup the DRAM etc). It is the same length as the on-chip
80 ;; ROM loads, so the same host loader can be used to load a rescued
81 ;; product as well as one booted through the Etrax serial boot code.
83 #define CODE_START 0x40000000
84 #define CODE_LENGTH 784
86 #ifdef CONFIG_ETRAX_RESCUE_SER0
87 #define SERXOFF R_SERIAL0_XOFF
88 #define SERBAUD R_SERIAL0_BAUD
89 #define SERRECC R_SERIAL0_REC_CTRL
90 #define SERRDAT R_SERIAL0_REC_DATA
91 #define SERSTAT R_SERIAL0_STATUS
93 #ifdef CONFIG_ETRAX_RESCUE_SER1
94 #define SERXOFF R_SERIAL1_XOFF
95 #define SERBAUD R_SERIAL1_BAUD
96 #define SERRECC R_SERIAL1_REC_CTRL
97 #define SERRDAT R_SERIAL1_REC_DATA
98 #define SERSTAT R_SERIAL1_STATUS
100 #ifdef CONFIG_ETRAX_RESCUE_SER2
101 #define SERXOFF R_SERIAL2_XOFF
102 #define SERBAUD R_SERIAL2_BAUD
103 #define SERRECC R_SERIAL2_REC_CTRL
104 #define SERRDAT R_SERIAL2_REC_DATA
105 #define SERSTAT R_SERIAL2_STATUS
107 #ifdef CONFIG_ETRAX_RESCUE_SER3
108 #define SERXOFF R_SERIAL3_XOFF
109 #define SERBAUD R_SERIAL3_BAUD
110 #define SERRECC R_SERIAL3_REC_CTRL
111 #define SERRDAT R_SERIAL3_REC_DATA
112 #define SERSTAT R_SERIAL3_STATUS
115 #define NOP_DI 0xf025050f
116 #define RAM_INIT_MAGIC 0x56902387
120 ;; This is the entry point of the rescue code
121 ;; 0x80000000 if loaded in flash (as it should be)
122 ;; Since etrax actually starts at address 2 when booting from flash, we
123 ;; put a nop (2 bytes) here first so we dont accidentally skip the di
128 jump in_cache ; enter cached area instead
132 ;; First put a jump test to give a possibility of upgrading the
133 ;; rescue code without erasing/reflashing the sector.
134 ;; We put a longword of -1 here and if it is not -1, we jump using
135 ;; the value as jump target. Since we can always change 1's to 0's
136 ;; without erasing the sector, it is possible to add new
137 ;; code after this and altering the jumptarget in an upgrade.
139 jtcd: move.d [jumptarget], $r0
140 cmp.d 0xffffffff, $r0
147 .dword 0xffffffff ; can be overwritten later to insert new code
150 #ifdef CONFIG_ETRAX_ETHERNET
151 ;; Start MII clock to make sure it is running when tranceiver is reset
152 move.d 0x3, $r0 ; enable = on, phy = mii_clk
153 move.d $r0, [R_NETWORK_GEN_CONFIG]
156 ;; We need to setup the bus registers before we start using the DRAM
157 #include "../../lib/dram_init.S"
159 ;; we now should go through the checksum-table and check the listed
160 ;; partitions for errors.
162 move.d PTABLE_START, $r3
164 cmp.d NOP_DI, $r0 ; make sure the nop/di is there...
168 ;; skip the code transparency block (10 bytes).
172 ;; check for correct magic
175 cmp.w PTABLE_MAGIC, $r0
176 bne do_rescue ; didn't recognize - trig rescue
179 ;; check for correct ptable checksum
181 movu.w [$r3+], $r2 ; ptable length
182 move.d $r2, $r8 ; save for later, length of total ptable
183 addq 28, $r8 ; account for the rest
184 move.d [$r3+], $r4 ; ptable checksum
186 jsr checksum ; r1 source, r2 length, returns in r0
189 bne do_rescue ; didn't match - trig rescue
192 ;; ptable is ok. validate each entry.
196 ploop: move.d [$r3+], $r1 ; partition offset (from ptable start)
197 bne notfirst ; check if it is the partition containing ptable
199 move.d $r8, $r1 ; for its checksum check, skip the ptable
200 move.d [$r3+], $r2 ; partition length
201 sub.d $r8, $r2 ; minus the ptable length
205 cmp.d -1, $r1 ; the end of the ptable ?
206 beq flash_ok ; if so, the flash is validated
207 move.d [$r3+], $r2 ; partition length
208 bosse: move.d [$r3+], $r5 ; checksum
209 move.d [$r3+], $r4 ; type and flags
210 addq 16, $r3 ; skip the reserved bytes
211 btstq 16, $r4 ; check ro flag
212 bpl ploop ; rw partition, skip validation
214 btstq 17, $r4 ; check bootable flag
217 move.d $r1, $r7 ; remember boot partition offset
219 add.d PTABLE_START, $r1
221 jsr checksum ; checksum the partition
224 beq ploop ; checksums matched, go to next entry
227 ;; otherwise fall through to the rescue code.
230 ;; setup port PA and PB default initial directions and data
231 ;; (so we can flash LEDs, and so that DTR and others are set)
233 move.b CONFIG_ETRAX_DEF_R_PORT_PA_DIR, $r0
234 move.b $r0, [R_PORT_PA_DIR]
235 move.b CONFIG_ETRAX_DEF_R_PORT_PA_DATA, $r0
236 move.b $r0, [R_PORT_PA_DATA]
238 move.b CONFIG_ETRAX_DEF_R_PORT_PB_DIR, $r0
239 move.b $r0, [R_PORT_PB_DIR]
240 move.b CONFIG_ETRAX_DEF_R_PORT_PB_DATA, $r0
241 move.b $r0, [R_PORT_PB_DATA]
243 ;; setup the serial port at 115200 baud
246 move.d $r0, [SERXOFF]
249 move.b $r0, [SERBAUD] ; 115.2kbaud for both transmit and receive
251 move.b 0x40, $r0 ; rec enable
252 move.b $r0, [SERRECC]
254 moveq 0, $r1 ; "timer" to clock out a LED red flash
255 move.d CODE_START, $r3 ; destination counter
256 movu.w CODE_LENGTH, $r4; length
260 #ifndef CONFIG_ETRAX_NO_LEDS
261 #ifdef CONFIG_ETRAX_PA_LEDS
262 move.b CONFIG_ETRAX_DEF_R_PORT_PA_DATA, $r2
264 #ifdef CONFIG_ETRAX_PB_LEDS
265 move.b CONFIG_ETRAX_DEF_R_PORT_PB_DATA, $r2
267 move.d (1 << CONFIG_ETRAX_LED1R) | (1 << CONFIG_ETRAX_LED2R), $r0
271 or.d $r0, $r2 ; set bit
274 1: not $r0 ; clear bit
277 #ifdef CONFIG_ETRAX_PA_LEDS
278 move.b $r2, [R_PORT_PA_DATA]
280 #ifdef CONFIG_ETRAX_PB_LEDS
281 move.b $r2, [R_PORT_PB_DATA]
283 #ifdef CONFIG_ETRAX_90000000_LEDS
284 move.b $r2, [0x90000000]
288 ;; check if we got something on the serial port
290 move.b [SERSTAT], $r0
291 btstq 0, $r0 ; data_avail
295 ;; got something - copy the byte and loop
297 move.b [SERRDAT], $r0
300 subq 1, $r4 ; decrease length
304 ;; jump into downloaded code
306 move.d RAM_INIT_MAGIC, $r8 ; Tell next product that DRAM is
311 ;; check r7, which contains either -1 or the partition to boot from
316 move.d PTABLE_START, $r7; otherwise use the ptable start
318 move.d RAM_INIT_MAGIC, $r8 ; Tell next product that DRAM is
323 ;; Helper subroutines
325 ;; Will checksum by simple addition
327 ;; r2 - length in bytes
328 ;; result will be in r0
331 moveq CONFIG_ETRAX_FLASH1_SIZE, $r6
333 ;; If the first physical flash memory is exceeded wrap to the second one
334 btstq 26, $r1 ; Are we addressing first flash?
339 1: test.d $r6 ; 0 = no wrapping
342 lslq 20, $r6 ; Convert MB to bytes
345 2: addu.b [$r1+], $r0
346 subq 1, $r6 ; Flash memory left
348 subq 1, $r2 ; Length left
354 3: move.d MEM_CSE1_START, $r1 ; wrap to second flash